Ciclos eficientes de carbono, nitrógeno y fósforo en el sistema agroalimentario europeo y procesos relacionados para mitigar las emisiones

Geographical location	Spain
Main geographical location (NUTS3)	Barcelona
Keywords	Fertilisation and nutrients management Waste, by-products and residues management Agricultural production system Soil management / functionality Fertilisation and nutrients management Climate and climate change Farming practice Farming equipment and machinery Supply chain, marketing and consumption Plant production and horticulture
Main funding source	Horizon 2020 (EU Research & Innovation programme)
Project Identification	Multi-actor project
Project type	Research project
Starting date	2018
End date	2023
Project status	Ongoing
Website	Circular Agronomics website

Title (in English):

CIRCULAR AGRONOMICS - Efficient Carbon, Nitrogen and Phosphorus cycling in the European Agri-food System and related up- and down-stream processes to mitigate emissions

Objective of the project (native language):

1. Incrementar el conocimiento de los flujos de C, N y P, y de su potencial para reducir el impacto ambiental a nivel de granja y regional bajo diferentes condiciones biogeográficas; 2. Cerrar los ciclos en los cultivos, de la ganadería al cultivo e incrementar la reutilización de aguas residuales y residuos de la industria alimentaria para mejorar la fertilidad del suelo y la eficiencia del uso de nutrientes; 3. Promover el desarrollo de diferentes prototipos de sistemas agroecológicos e incrementar la sostenibilidad de la producción de alimentos en la UE; 4. Contribuir a la mejora de las políticas agrícolas europeas aportando recomendaciones de los agricultores y los consumidores.

Objective of the project (in English):

1. Increase the understanding of C, N, P flows and the related potential to reduce environmental impacts at farm and regional level under different bio-geographical conditions; 2. Closing loops within cropland farming, from livestock to cropland farming and to increase the reuse of waste/wastewater from food-industry to improve soil fertility and to increase nutrient use efficiency; 3. Highlight the performance of different prototypes of agro-ecological systems and increase sustainability of food production in the EU; 4. To contribute to the improvement of the European Agricultural Policies by providing evidence based, farmer led and consumer relevant recommendations for the agri-food chain

Description of activities (native language):

Análisis de las reservas, los flujos y las emisiones de C, N y P en sistemas agro-ganaderos; Mejora del reciclaje de C, N y P en la interfase suelo-planta; Estrategias de aplicación de fertilizantes; Estrategias de alimentación animal, emisiones y características del purín; Demostración de tecnologías innovadoras para la valorización y el reciclaje de residuos agro-ganaderos y minimizar emisiones; Clasificación de residuos y aguas residuales de la industria alimentaria y su potencial de reciclaje de C, N y P; Demostración de tecnologías de tratamiento innovadoras para la recuperación y el reciclaje de C, N y P de residuos (y aguas residuales) alimentarios. Análisis socio-económico y ambiental

Description of activities (in English):

Analysis of C, N and P stocks, flows and emissions in crop farming; Increase internal C, N and P cycling in the soil-plant interface; Fertilizer application strategies; Animal Feeding strategies, gaseous emissions and manure characteristics; Demonstration of innovative treatment technologies increasing efficiencies in valorisation and recycling of
livestock/agricultural residues and minimizing emissions; Classification of food waste and wastewater streams in food industry and their recycling potential for C, N
and P; Pilot Demonstration of innovative treatment technologies for recovery/recycling of C, N and P from food (waste)water; Socio-economic and Environmental analysis

Project coordinator

Contact person:

Institut de Recerca i Tecnologia Agroalimentaries (IRTA)

Address:

Torre Marimon, crta. C-59, km 12,1, E-08140 Caldes de Montbui-Barcelona-Spain

E-mail:

victor.riau@irta.cat

Phone:

+34 934 674 040

Partner category:

Researcher

Project partners

Contact person:

Institut de Recerca i Tecnologia Agroalimentaries (IRTA)

Address:

Torre Marimon, crta. C-59, km 12,1, E-08140 Caldes de Montbui-Barcelona-Spain

E-mail:

victor.riau@irta.cat

Phone:

+34 934 674 040

Partner category:

Researcher

Contact person:

Kompententzzentrum Wasser Berlin Gemeinnutzige Gmbh (KWB)

Address:

Cicerostrasse 24, Berlin 10709, Germany

E-mail:

fabian.kraus@kompetenz-wasser.de

Phone:

+49 30 53653 845

Partner category:

Researcher

Contact person:

Wageningen University (WUR)

Address:

Droevendaalsesteeg 4, Wageningen 6708 Pb, Netherlands

E-mail:

janwillem.vangroenigen@wur.nl

Phone:

+31 (0) 317 484784

Partner category:

Researcher

Contact person:

Verein Zur Forderung Agrar- Und Stadtokologischer Projekte (Asp) Ev Institut Fur Agrar-Und Stadtokologische Projekte An Der Humboldt (IASP)

Address:

Philippstrasse 13, Berlin 10115, Germany

E-mail:

andreas.muskolus@iasp.hu-berlin.de

Phone:

+49 (0) 30 20939 042

Partner category:

Researcher

Contact person:

Technische Universitaet Muenchen (TUM)

Address:

Arcisstrasse 21, Muenchen 80333, Germany

E-mail:

julien.guigue@tum.de

Phone:

+49(0)8161 71 4425

Partner category:

Researcher

Contact person:

Hoehere Bundeslehr- Und Forschungsanstalt Fuer Landwirtschaft Raumberg-Gumpenstein (AREC)

Address:

Raumberg 38, Irdningdonnersbachtal 8952, Austria

E-mail:

markus.herndl@raumberg-gumpenstein.at

Phone:

+43 3682 22451 340

Partner category:

Researcher

Contact person:

Centre De Recerca En Economia I Desenvolupament Agroalimentari Upc-Irta (CREDA)

Address:

Parc Mediterrani De La Tecnologia Edifici Esab C/Esteve Terrrades 8, Castelldefels 08860, Spain

E-mail:

zein.kallas@upc.edu

Phone:

+34 935 521 213

Partner category:

Researcher

Contact person:

Teagasc - Agriculture And Food Development Authority (TEA)

Address:

Oak Park, Carlow, Ireland

E-mail:

sinead.mccarthy@teagasc.ie

Phone:

+353 1 8059962

Partner category:

Researcher

Contact person:

Fondazione Crpa Studi Ricerche (FCSR)

Address:

Viale Timavo 43/2, Reggio Emilia 42121, Italy

E-mail:

p.mantovi@crpa.it

Phone:

+39 0522 436999

Partner category:

Other

Contact person:

The Rural Investment Support For Europe Foundation (RISE)

Address:

Rue De Treves 67, Bruxelles 1040, Belgium

E-mail:

elisabet.nadeu@risefoundation.eu

Phone:

+32 2 234 30 00

Partner category:

Other

Contact person:

Sogesca S.R.L. (SOG)

Address:

Via Pitagora 11 A, Rubano 35030, Italy

E-mail:

m.devetta@sogesca.it

Phone:

+39 3460 684038

Partner category:

SME

Contact person:

Pondus Verfahrenstechnik Gmbh (PON)

Address:

Luise-Von-Werdeckstrasse 24, Teltow 14513, Germany

E-mail:

info@pondus-verfahren.de

Phone:

+49 3328 339 6840

Partner category:

SME

Contact person:

Ema Depuracio I Enginyeria De L'Aigua (EMA)

Address:

Avda Sant Jordi 176, Olot 17800, Spain

E-mail:

adm@edepura.com

Phone:

+34 972 27 64 53

Partner category:

SME

Contact person:

Nutrients Recovery Systems (NRS)

Address:

Hoekstraat 3, Deerlijk 8540, Belgium

E-mail:

info@akwadok.be

Phone:

+32 476225466

Partner category:

SME

Contact person:

Eastern Africa Farmers' Federation Society (EAFF)

Address:

Rhapta Road Nelleon Place Westlands, Nairobi 00800, Kenya

E-mail:

norbert.tuyishime@gmail.com

Phone:

+25 4204451691

Partner category:

Other

Contact person:

Asio Spol Sro (ASIO)

Address:

Ksirova 552/45, Brno 619 00, Czech Republic

E-mail:

holba@asio.cz

Phone:

+42 0606610347

Partner category:

SME

Contact person:

Soepenberg Fertilizers Bv (SOE)

Address:

Parkweg 15, Deventer 7411 Sg, Netherlands

E-mail:

j.clemens@soepenberg.com

Phone:

+31 570758035

Partner category:

SME

Contact person:

Eidgenoessisches Departement Fuer Wirtschaft, Bildung Und Forschung (AGRO)

Address:

Bundeshaus Ost, Bern 3003, Switzerland

E-mail:

gerard.gaillard@agroscope.admin.ch

Phone:

+41 58 468 73 50

Partner category:

Researcher

Contact person:

Porgaporcs Sl (PGP)

Address:

Partida De La Segarra, Vila Sana 25245, Spain

E-mail:

aportaga@gmail.com

Phone:

+34 973070608

Partner category:

Farmer

Practice summary

Practice abstract 1

Short title (in English):

Effects of conservation tillage on crop production and soil quality

Short summary for practitioners (in English):

Conservation agriculture is based on three pillars: 1) minimum soil disturbance (from minimum tillage to direct seeding) 2) crop rotation 3) continuous soil coverage, with crops or their residues. The assumption is that the soil structure and porosity develop and maintain thanks to the action of the roots and organisms living in the soil, especially earthworms.
Generally speaking, the transition from conventional to conservation tillage requires the so-called "transition period" during which the soil (and the farmer!) adapt to the new system. It has been proven that crop productivity in conservation tillage systems can reach (and exceed) the level as in conventional farming and is generally more stable after a few years of adoption, benefiting from the increased resilience of the agricultural system.
Among the parameters that contribute to quantify soil quality, in conservation tillage regimes there is generally an increase in the organic matter stock, especially in the shallow layers of the soil, as well as the soil aggregate stability, which represents resistance to degradation by water.
In the Circular Agronomics project, the effects of some conservation tillage techniques, both on crop production and soil quality, are studied within the case study of the Emilia-Romagna Region (Italy), with and without the application of exogenous organic matter (digestate).

Short title (native language):

Effetti dell'agricoltura conservativa sulle produzioni vegetali e sulla qualità del suolo

Short summary for practitioners (native language):

L’agricoltura conservativa si fonda su tre pilastri: 1) il minimo disturbo del suolo (dalle minime lavorazioni alle semina diretta) 2) la rotazione delle colture 3) copertura continua del terreno, con le coltivazioni o loro residui. Il presupposto è che la struttura e porosità del suolo si sviluppino e mantengano grazie all’azione delle radici e di organismi che vivono nel suolo, in primo luogo i lombrichi.
Generalmente il passaggio dal regime di agricoltura convenzionale a quello conservativo necessita del cosiddetto “periodo di transizione” nel corso del quale il suolo (e l’agricoltore!) si adattano al nuovo sistema. È stato dimostrato che la produttività delle coltivazioni nei regimi di agricoltura conservativa può raggiungere lo stesso livello (o superiore) del convenzionale e generalmente, dopo alcuni anni di adozione, risulta più stabile avvantaggiandosi della accresciuta resilienza del sistema agricolo.
Tra i parametri che contribuiscono a quantificare la qualità del suolo, nei regimi di agricoltura conservativa in generale si assiste ad un incremento dello stock di sostanza organica, specie negli strati più superficiali del terreno, così come della stabilità strutturale, che rappresenta la resistenza alla degradazione da parte dell'acqua.
Nel progetto Circular Agronomics gli effetti di alcune tecniche di agricoltura conservativa, sia sulle produzioni agricole che sulla qualità del suolo, vengono studiati all’interno del caso di studio della regione Emilia-Romagna (Italia), con e senza l'applicazione di materia organica esogena (digestato).

Practice abstract 2

Short title (in English):

Effect of nitrification inhibitors on crop growth and yields

Short summary for practitioners (in English):

Agricultural plants mainly take up nitrogen in the form of nitrate. On-farm produced fertilizers like farmyard manure, slurry, or biogas digestate do not contain any nitrate but nitrogen in form of ammonia. After soil application, bacteria transform ammonia into nitrate which then can be taken up by plants. However, nitrate is also susceptible to leaching into ground water while ammonia is not. Best growth and highest yields are reached when the needed amount of nitrate is available to the crops at every point of time. In most cases, the transfer from ammonia to nitrate takes about only two weeks. Depending on the crop and time in the year, plant nitrate uptake needs much more time. A nitrification inhibitor (NI) downregulates the bacterial activity during the conversion of ammonium into nitrate in the soil. As a result, the plant nutrient nitrate is available at a later time. Thus, it can help to better match nutrient supply and demand. But NIs do not automatically improve crop development: When not nitrogen but water is limiting pant growth, the delay in nutrient supply means no advantage. From a crop nutritional point of view NIs should be used only, when there is a clear need for delaying and slowing down the nitrate supply. This can be the case when limited slurry storage capacity requires an early application time, weeks before maize planting or applications at a more optimum time during crop growth are technically unfeasible. The use of NIs has positive side effects: It can potentially reduce the amount of N2O emitted to the atmosphere. N2O is a very active greenhouse gas. However, because commercially available NIs consist of complex formulations, they may leave trace residues in the environment.

Short title (native language):

Die Wirkung von Nitrifikationsinhibitoren auf Pflanzenwachstum und Erträge

Short summary for practitioners (native language):

Landwirtschaftliche Nutzpflanzen nehmen Stickstoff meist in Form von Nitrat auf. Wirtschaftsdünger wie Stallmist, Gülle und Biogas-Gärrest enthalten nicht Nitrat sondern Stickstoff in Form von Ammonium. Nach der Ausbringung wandeln Bakterien im Boden das Ammonium in Nitrat um was dann von den Pflanzen aufgenommen werden kann. Anders als Ammonium kann Nitrat im Boden jedoch leicht ausgewaschen werden. Es verschmutzt dann Grundwasser. Das beste Wachstum und die höchsten Erträge werden erreicht, wenn zu jedem Zeitpunkt genug Nitrat zur Verfügung steht. Bei warmer Witterung dauert die Umwandlung zu Nitrat etwa 2 Wochen. Bis der Nährstoff von den Pflanzen aufgenommen ist vergeht meist deutlich mehr Zeit. Ein Nitrifikationsinhibitor (NI) verzögert die Bakterienaktivität, dadurch dauert es länger bis aus dem Ammonium Nitrat geworden ist. Dadurch kann eine bessere Anpassung des Stickstoff-Angebots und der Aufnahme durch Pflanzen erfolgen. NIs verbessern das Pflanzenwachstum aber nicht unter allen Umständen. Wenn Trockenheit das Wachstum limitiert ergibt sich aus der Verzögerung des Stickstoffangebotes kein Vorteil. Aus pflanzenbaulicher Sicht sollten NIs nur eingesetzt werden, wenn es einen klaren Grund zur Verzögerung der bakteriellen Umwandlung gibt. Dies ist z.B. gegeben wenn limitierte Lagerkapazitäten die Gülleausbringung schon Wochen vor der Maisausaat erfordern oder die Ausbringung zum optimalen Zeitpunkt aus technischen Gründen nicht möglich ist. Die Verwendung von NIs hat positive Nebeneffekte: Sie können unter Umständen Lachgasemissionen reduzieren. Nicht auszuschließen ist jedoch, dass die teilweise komplexen Verbindungen für eine Zeit lang Rückstände im Boden hinterlassen.

Practice abstract 3

Short title (in English):

Effect of slurry application method on nutrient uptake and yield

Short summary for practitioners (in English):

Slurry consists of animal excreta and residues of straw and feed as well as water. Because it contains nitrogen, phosphorus and potassium, it is used as a valuable fertilizer. Returning the nutrients to agricultural fields and grassland means closing loops and using an almost perfect recycling system. However, losses from this system can occur, that do harm the environment. The plant nutrient nitrogen is contained in slurry in the form of ammonium. It has the tendency to volatize into its gaseous form: Ammonia. In order to make good use of the nutrient, these gaseous emissions have to be minimized. Following some simple guidelines when applying slurry may result in drastic reduction of emissions: 1. Only apply when there are growth conditions and plants can take up the nutrient. 2. Avoid high temperatures 3. Use an application method that minimizes the contact of slurry with air. Traditionally, broad spread technologies (splash plate) was used for the distribution of slurries. They cause a maximum of slurry-air contact and therefore a maximum of ammonia emissions. A band spreader means a significant improvement because it applies the liquid fertiliser in narrow bands (reducing the slurry surface on land) and the use of distributing pipes ensures reduced air contact. Even better are slurry “injectors” or “under-feet” application systems which pump the slurry directly into the soil and ideally near to the root zone. Their use, however, may harm the existing plant canopy. Any loss of nitrogen in form of ammonia means the nutrient cannot be used by the crops anymore. A reduced nutrient efficiency and reduced yields are the result. Usually more than 30 % of the ammonia is lost when using a traditional splash plate spreader at warm weather.

Short title (native language):

Der Einfluss der Gülle-Ausbringungstechnik auf die Nährstoffaufnahme und den Ertrag von Nutzpflanzen

Short summary for practitioners (native language):

Gülle besteht aus tierischem Ausscheidungen, Stroh- und Futterresten sowie Wasser. Weil es Stickstoff, Phosphor und Kalium enthält ist es ein wertvoller Dünger. Diese Nährstoffe zurück auf landwirtschaftliche Flächen zu bringen bedeutet Kreisläufe zu schließen – ein fast perfektes Recyclingsystem. Nährstoffverluste aus diesem System sind jedoch mit negativen Folgen für Wasser und Luft verbunden. Gülle enthält den Pflanzennährstoff Stickstoff zu einem wesentlichen Teil als Ammonium. Dieses hat die Tendenz in Form von Ammoniak auszugasen. Um die Nährstoffe effizient nutzen zu können müssen Ammoniak-Emissionen deshalb vermieden werden. Das ist auf folgende Weise möglich: 1: Gülle nur ausbringen, wenn die Nährstoffe durch Pflanzenwachstum aufgenommen werden können. 2. Ausbringung bei hohen Temperaturen vermeiden. 3. Die Verwendung einer Ausbringungstechnik, die den Kontakt der Gülle mit Luft reduziert. Herkömmlich wurde Gülle mit einem Prallteller ausgebacht. Dabei ist die Gülle viel mit Luft in Kontakt und wird breit auf der Fläche verteilt was hohe Ammoniakemissionen verursacht. Demgegenüber bedeutet die Ausbringung mit Schleppschläuchen einen Fortschritt. Noch stärker werden Ammoniakemissionen durch den Einsatz von Gülle-Injektoren oder der Unterfuß-Ausbringung reduziert. Diese befördern die Gülle mit minimalem Luftkontakt in die Wurzelzone. Ihr Einsatz ist jedoch nur eingeschränkt möglich da er bereits gewachsene Nutzpflanzen beschädigen kann. Ammoniakemissionen bedeuten auch immer einen Verlust von Nährstoffen und damit eine Verschlechterung der Nährstoffeffizienz. Aus bei warmer Witterung mit Prallteller ausgebrachter Gülle gehen üblicherweise 30 % des enthaltenden Ammoniums verloren.

Practice abstract 4

Short title (in English):

Effect of wheat genotype selection on N nutrient efficiency under conditions of reduced N supply

Short summary for practitioners (in English):

Wheat varieties (genotypes) differ in a number of ways: Climatic conditions they prefer to grow in, potential yields, and internal qualities related to the use of the grain. Differences also exist in the way how flexible the plant reacts to changing growth conditions. Generally, this means the presence of water, enough temperature, sunlight, and nutrients. While the number of grains per area is a result of good growing conditions at the start, the size and weight of single grains is formed later in the growing season. More close to harvest, fertilization strongly influences the quality of the grain - mainly the protein content. Genotypes differ in their sensitivity to nitrogen supply at different growing stages. A good nutrient efficiency means getting back all nutrients applied during fertilization in the harvested materials. Bad nutrient efficiencies are mostly a result of difficult growing conditions other than the nutrient supply (low temperatures, drought, diseases) or over-supply of nutrients. Current unbalances in European agriculture strongly suggest reducing the amount of nitrogen applied. This, however, can result in grain qualities insufficient for the intended use, especially for bread-making. In order to reach a nitrogen balance without excess, the choice of wheat genotype must fit to the expected growing conditions. If nitrogen supply is reduced (e.g. in order to minimize overbalances), the effect on the internal quality of the grain is much greater than the effect on the yield. If animal feed is the production goal, a high yielding variety with low protein content should be chosen. If bread for human consumption is the goal, a high protein genotype with good internal quality but lower yield is best.

Short title (native language):

Winterweizen-Sortenwahl bei reduzierter Stickstoffdüngung mit Blick auf die Nährstoffeffizienz

Short summary for practitioners (native language):

Weizensorten (Genotypen) können sich auf vielfältige Art unterscheiden: Präferierte klimatische Bedingungen, Ertragspotenzial und Qualitätseigenschaften. Weitere Unterschiede bestehen darin wie flexibel die Pflanzen auf sich verändernde Wachstumsbedingungen reagieren. Das meint im Allgemeinen das Vorhandensein von Wasser, geeigneter Temperatur, Sonnenlicht und Nährstoffen. Während die Anzahl Körner je Fläche ein Ergebnis guter Wachstumsbedingungen in einer frühen Phase ist, wird das Gewicht einzelner Körner (Tausendkorngewicht) später ausgebildet. Wenige Woche vor der Ernte beeinflusst die Düngung nur noch die innere Qualität, und davon hauptsächlich den Proteingehalt. Weizensorten unterscheiden sich darin, wie stark sie auf das Angebot an guten Wachstumsbedingungen in verschiedenen Entwicklungsphasen reagieren. Eine gute Nährstoffeffizienz bedeutet, dass alle Nährstoffe die mit dem Dünger ausgebracht wurden auch wieder in den geernteten Pflanzenteilen den Acker verlassen. Schlechte Nährstoffeffizienzen sind meist ein Ergebnis schwieriger Wachstumsbedingungen wie tiefe oder zu hohe Temperaturen, Trockenheit oder Krankheiten und Schädlinge. Aktuelle Stickstoffüberschüsse im Weizenanbau legen eine Reduzierung der Nährstoffmenge nahe, was jedoch zu Qualitätsverlusten führen kann. Um Nährstoffüberschüsse zu vermeiden muss die Sortenwahl deshalb den Wachstumsbedingungen angepasst werden. Stickstoffreduktionen führen bei Weizen meist deutlicher zu Veränderungen der inneren Qualitätsparameter, als zu Ertragsveränderungen. Die Auswahl der Sorten sollte unbedingt dem Produktionsziel (Z.B. Futter- oder Brotweizen) angepasst werden.

Practice abstract 5

Short title (in English):

Effect of wheat genotype on bread-making quality under conditions of reduced N supply

Short summary for practitioners (in English):

Wheat is the main ingredient of bread for human consumption. But not all wheat is in the same way suitable to be used for baking bread. In order to reach a certain quality of bread, easily measureable criteria were defined. These criteria are used when trading wheat. Farmers get payed according to these criteria. One of the most important criteria that was historically established for assessing the wheat quality is the total protein content of the grain. The protein content is widely influenced by nitrogen fertilization at a late growth stage. Because this is typically in the summer season, there is a high risk of plants not being able to make use of the nutrient because of drought. Additionally, the protein content quickly drops when cereals ripe for harvest receive rainfall. However, the protein content is just one quality measure when it comes to how good wheat flour is suitable for baking bread. According to recent research, a suitable protein composition is more important to baking qualities than the total protein content. With a modern variety it is possible to generate bread-making quality of wheat even while reducing the total amount of nitrogen fertilizer. But reducing fertilization is risky for the farmer because the international marked price of wheat is still related to its total protein content. Wheat with a lower protein content gets payed less. Selling wheat of modern varieties to local mills and bakeries who are interested in actual bread-making quality and not just in high protein contents may allow to reduce nitrogen fertilization. In this way, choosing wheat genotypes with a good protein composition helps reducing nitrogen overbalances.

Short title (native language):

Winterweizen-Sortenwahl bei reduzierter Stickstoffdüngung mit Blick auf die Backqualität

Short summary for practitioners (native language):

Weizen ist der Hauptbestandteil von Brot für die menschliche Ernährung. Nicht jeder Weizen ist jedoch gleich gut zum Brotbacken geeignet. Um beim Weizen zuverlässig gute Backqualitäten zu erreichen wurden leicht messbare Parameter definiert. Nach diesen historisch gewachsenen Kriterien wird Winter-Weichweizen gehandelt. Einer der wichtigsten dieser Parameter ist der Proteingehalt des Korns. Dieser wird wesentlich von der Stickstoffdüngung in der späten Wachstumsphase beeinflusst. Wegen Trockenheit können die Pflanzen die Nährstoffe dieser späten Düngung oft nicht aufnehmen. Außerdem besteht die Gefahr, dass Regen zur Erntezeit die Proteingehalte sinken lässt. Der Proteingehalt ist jedoch nur ein Kriterium, wenn es darum geht wie gut sich ein Weizenmehl tatsächlich zum Brotbacken eignet. Neuere wissenschaftliche Erkenntnisse zeigen, dass die Zusammensetzung des Proteins die Backqualität stärker als der Proteingehalt beeinflusst. Moderne Weizensorten ermöglichen es auch bei reduzierter Stickstoffgabe Mehl mit guten Backeigenschaften zu erzeugen. Doch auf eine hohe Stickstoffdüngung zu verzichten ist riskant für Landwirte, weil sich der Weltmarktpreis am Proteingehalt orientiert. Der Verkauf von Backweizen an regionale Mühlen oder Bäckereien die an der tatsächlichen Backqualität und nicht am Proteingehalt interessiert sind kann eine Reduktion der Stickstoffgabe ermöglichen. Auf diese Art hilft der Einsatz modernen Brotweizensorten mit einer guten Eiweiß-Zusammensetzung Stickstoffüberschüsse in der Bilanz abzubauen.

Practice abstract 6

Short title (in English):

Using the dried digestate from an agro-industrial biogas plant as a fertilizer

Short summary for practitioners (in English):

From an economic point of view, intensive livestock is a very important activity in our country. However, it produces a large amount of organic waste for which recovery as fertilizers is sought. At present, the use of raw slurries in the fields near pig farms is common, but the excess of its use has led to contamination by nitrates and even phosphorus, with the consequent degradation of soils and water tables in aquifers. European regulations are therefore increasingly restrictive in terms of the type of product, form, dose and times of application of all fertilizer products including organic products. Circular Agronomics is studying the usefulness of a new dry pig digestate, obtained in anaerobic digestion plants, to be used as fertilizer in field crops. The slurry is digested after which a liquid digestate is obtained, being later acidified and dried. Half of the nitrogen in the dry digestate is in ammoniacal form and the other half in the form of organic nitrogen. Its slightly acidic pH, and its easy transport are among its advantages, since most of the water from the slurry or the digestate has been eliminated during the process. The effectiveness of its distribution is improved due to the higher concentration in N. At the end of Circular Agronomics, the application of dry digestate as a fertilizer product in the field is expected to be cheaper and easier than the current liquid products. The acidified and dried digestate is a product to be used within a rational planning in the fertilization plan of any exploitation, depending on the needs of the crop and always within the frame of current legislation

Short title (native language):

Uso del digestato seco de una planta de biogás agroindustrial como fertilizante

Short summary for practitioners (native language):

La ganadería intensiva es una actividad muy importante en nuestro país desde el punto de vista económico. Sin embargo, produce una gran cantidad de residuos orgánicos para los que se busca una valorización como fertilizantes. En la actualidad es habitual el uso de purines crudos en los campos próximos a las granjas porcinas, pero el exceso de este uso ha llevado a la contaminación por nitratos e incluso fósforo, con la consecuente degradación de suelos y aguas en los acuíferos. La normativa europea es por ello cada vez es más restrictiva en cuanto al tipo de producto, forma, dosis y momentos de aplicación de todos los productos fertilizantes incluidos los orgánicos.El digestato seco acidificado es un producto que se debe utilizar dentro de una planificación racional en el plan de fertilización de la explotación, en función de las necesidades del cultivo y siempre dentro de lo que marca la legalidad vigente. En Circular Agronomics se está estudiando la utilidad de un nuevo digestato seco del purín de cerdo procedente de las plantas de digestión anaerobia para su uso como fertilizante en cultivos extensivos. El purín se somete a una digestión con lo que se obtiene un digestato líquido, que más tarde es acidificado y secado. El digestato seco tiene la mitad de su nitrógeno en forma amoniacal y la otra mitad en forma de nitrógeno orgánico, y entre sus ventajas se encuentran su pH ligeramente ácido, y su fácil transporte debido a que la mayor parte del agua del purín o del digestato líquido se ha eliminado durante el proceso. Al ser más concentrado en riqueza de N se puede mejorar la efectividad de la distribución. Al final de Circular Agronomics, la aplicación del digestato seco en el campo se espera que sea más económica y fácil que los líquidos como producto fertilizante.

Practice abstract 7

Short title (in English):

Advantages of crop rotation

Short summary for practitioners (in English):

In Europe, cereal crops have a good adaptation to the environment, where a total crop failure is very rare, so cereals are the only cultivated species in some areas. Some farmers have traditionally opted to grow one or two cereal species (especially barley and wheat), with simple requirements for cultivation and a low technological complication. The current European regulation (CAP) has a requirement for crop diversification (known as Greening) that requires farms to include different species in their fields. Some farmers have chosen to add an additional species of cereal to the rotation, mainly triticale or oats, or even fallow. However, crop diversification can be more beneficial by using crops from other families, such as legumes or crucifers, with biological characteristics different from those of cereals. Complementing a cereal rotation with a year of rapeseed (cruciferous) can help in the control of grasses, diseases and some pests. If we also add a legume species, such as the protein pea, we can save a certain amount of nitrogen fertilizer, along with its application expense, due to the nitrogen fixing capacity associated with legumes. Circular Agronomics aims to analyse the advantages of this crop diversification through its effect on yield and on the dynamics of essential nutrients such as N and P. Although considering the crop obtained only one year it is possible that a cereal is the most profitable crop, a biodiverse rotation can bring certain advantages that can lead to greater sustainability of long-term exploitation.

Short title (native language):

Ventajas de la rotación de cultivos

Short summary for practitioners (native language):

Los cultivos de cereales presentan una buena adaptación al ambiente en Europa, y raramente se produce un fallo total del cultivo, por lo que en algunas zonas son las únicas especies cultivadas. Algunos agricultores han optado por cultivar una o dos especies de cereales (especialmente cebada y trigo), con requerimientos sencillos para el cultivo y poca complicación tecnológica. La actual regulación europea (PAC) tiene un requerimiento de diversificación de cultivos (conocido como Greening) que requiere que las explotaciones incluyan diferentes especies. Algunos agricultores han optado por añadir una especie más de cereal a la rotación, básicamente triticale o avena, o incluso el barbecho. Sin embargo, la diversificación de cultivos se puede ver beneficiada utilizando cultivos de otras familias, como las leguminosas o las crucíferas, con características biológicas distintas a las de los cereales. Complementar una rotación de cereales con un año de colza (crucífera) puede ayudar en el control de malas hierbas de hoja estrecha, enfermedades y algunas plagas. Si además añadimos una leguminosa, como el guisante proteaginoso, podemos ahorrar una cierta cantidad de fertilizante nitrogenado, junto con el correspondiente gasto de aplicación, debido a la capacidad fijadora de nitrógeno asociada a las leguminosas. En Circular Agronomics se pretende analizar las ventajas de esta diversificación de cultivos a través de su efecto sobre el rendimiento y sobre la dinámica de nutrientes esenciales como el N y P. A pesar de que considerando la cosecha obtenida un solo año es posible que un cereal sea el cultivo más rentable, una rotación biodiversa puede aportar ciertas ventajas que pueden llevar a una sostenibilidad mayor de la explotación a largo plazo.

Practice abstract 8

Short title (in English):

Ammonia volatilization from agriculture

Short summary for practitioners (in English):

Catalonia is one of Europe’s hot spots on Ammonia emissions (together with Britany, Po valley and the area of N-W Germany, Belgium and the Netherlands). On average, 57 kg NH3 are emitted for each hectare devoted to agriculture, coming from agriculture and livestock farming, mainly from manure management. Ammonia emissions may produce high concentration of ammonia on atmosphere and, thus, directly affect agricultural land, natural ecosystems and human health. Ammonia on atmosphere may come from the transformation of nitrogen (N) on ammonia or urea form. Once volatilization has occurred, ammonia may interact with other elements in atmosphere and enhance its pollution effects.
The loss of N through ammonia volatilization reduces nutrient use efficiency on agriculture and produces a significant economic loss on farms. It also produces environmental pollution, mainly on atmosphere (reacting with other pollutants increases the abundance of fine particles, PM10), water bodies, soils and natural ecosystems – through eutrophication and acidification.
Since 2010 different norms are limiting que level of ammonia emissions allowed, although the objectives have not been achieved in many cases.
Circular Agronomics works on different agricultural practices devoted to improve manure management and its nutrient use efficiency, including the study of techniques and types of management able to minimize ammonia volatilization from the fertilization of crops with manure and its derived products.

Short title (native language):

Emissions d’amoniac de l’agricultura

Short summary for practitioners (native language):

Catalunya és una de les àrees europees amb majors emissions d’amoníac (amb Bretanya, la vall del Po i l’àrea al voltant del nord-oest d’Alemanya, els Països Baixos I Bèlgica). De mitjana s’emeten 57 kg NH3 per hectàrea dedicada a l’agricultura, provinents de l’agricultura i la ramaderia, principalment de la gestió de les dejeccions ramaderes. Les emissions d’amoni poden comportar un increment de la concentració d’amoni a l’atmosfera i, per tant, afectar directament les explotacions agràries, els sistemes naturals i la salut humana. L’amoni en l’atmosfera pot procedir de la transformació de nitrogen (N) en forma ureica o amoniacal. Un cop l’amoni s’ha volatilitzat, interactua amb altres elements presents en l’atmosfera i augmenta els seus efectes contaminants.
La pèrdua de N per volatilització redueix l’eficiència en l’ús d’aquest nutrient en les explotacions agrícoles i produeix pèrdues econòmiques significatives a les explotacions. També es provoca contaminació ambiental, principalment a l’atmosfera (reaccionant amb altres contaminants augmenta l’abundància de partícules fines, PM10), masses d’aigua, sòls i sistemes naturals -a través de processos d’eutrofització i acidificació.
Des de l’any 2010 diferent normativa limita el nivell d’emissions d’amoníac permès, però els objectius plantejats no s’han assolit en molts casos.
Circular Agronomics treballa en diferents practiques agrícoles orientades a millorar el maneig de les dejeccions i l’eficiència en l’ús dels nutrients que contenen, incloent l’estudi de tècniques i tipus de maneig que minimitzin la volatilització d’amoníac provinent de la fertilització dels cultius amb dejeccions i productes que en deriven.

Practice abstract 9

Short title (in English):

Reducing ammonia volatilization from crop fertilization practices

Short summary for practitioners (in English):

In Catalonia, 96 % of ammonia emissions come from farming. The main part (71 %) is caused by manure management in a broad sense: from animal excretion to manure incorporation to land. There are circumstances that may enhance volatilization from crop fertilization: calcareous soils, top application, wind, temperature, type of fertilizer, ... On the other hand, several fertilization practices may reduce volatilization when applying fertilizers to agricultural land. Circular agronomics works on several of these practices and at the end of the project several solutions will be handed out for enhancing nutrient use efficiency on crop fertilization.
In general, several advices may be provided. To reduce ammonia volatilization, use products with N in organic form (i.e.: compost) rather than in ammonia form (i.e.: pig slurry). For slurries and liquid fractions: avoid broad application equipment; when application on top of the soil, incorporate it short after; do not apply when wind is forecasted; and apply when rainfall is forecasted for the following days. For solid manure, incorporate it into the soil short after application, especially when high content of N on ammonia form (i.e.: chicken manure). For mineral fertilizers: use those containing N in nitrate form, especially on wet-hot periods; incorporate fertilizers into the soil always when possible; and do not apply N fertilizers all rate at once, split the rate along the crop cycle.

Short title (native language):

Reduir la volatilizació d’amoníac en les pràctiques de fertilització dels cultius

Short summary for practitioners (native language):

A Catalunya, el 96 % de les emissions d’amoníac provenen de l’activitat agrària. Principalment (71%) és causada per la gestió de les dejeccions en un sentit ampli: des que els animals les excreten fins que s’incorporen al sòl. Hi ha circumstàncies que poden incrementar la volatilització en la fertilització dels cultius: sòls calcaris, aplicació en superfície, vent, temperatura, tipus de fertilitzants, … D’altra banda, algunes practiques de fertilització poden reduir la volatilització quan s’apliquen fertilitzants. Circular Agronomics treballa en diverses d’aquestes practiques i, al final del projecte, es donaran diverses solucions per millorar l’eficiència en l’ús dels nutrients en la fertilització dels cultius.
En general, es poden donar alguns consells. Per reduir la volatilització d’amoníac, usar productes amb N en forma orgànica (p.ex.: compost) millor que en forma amoniacal (p.ex.: purí porcí). Per purins i fraccions líquides: evitar aplicacions en ventall; quan s’aplica en superfície, incorporar al sòl tan aviat com es pugui; no aplicar quan hi ha o s’espera vent; i aplicar quan es preveu pluja en els següents dies. Per dejeccions sòlides, incorporar al sòl quan abans millor, especialment per aquells productes amb un contingut alt de N en forma orgànica (p.ex.: gallinassa). Pels fertilitzants minerals: usar els que continguin N en forma nítrica, especialment en períodes amb calor i humitat; incorporar els adobs al sòl sempre que sigui possible; i no aplicar tota la dosi de N en un sol moment, fraccionar la dosi al llarg del cicle del cultiu.

Practice abstract 10

Short title (in English):

Suitability of different manure and derived products as fertilizers on arable crops

Short summary for practitioners (in English):

Crops have different nutrient needs in diverse moments of their cycle. Nutrients in fertilizers, namely manure, may be found on different forms and levels of availability for crops. For the fertilization of arable crops, different types of manure (farmyard manure, slurry,…) may be applied, some of them at different moments, either before sowing or at early side-dressing. The form in which nutrients are present in each type of manure may make them more suitable for applications in different moments of the crop cycle or the crop rotation. Nitrogen (N) in pig slurry is mainly (65-75 %) in ammonium form, quickly available for crop absorption and, thus, to be applied when crop needs are high -i.e.: side-dressing in winter cereals- or are about to be. In dairy farm-yard manure N is mainly organic. It will be available for crop nutrition on the mid-long run, often several years after application. It must be better applied before the sowing period, when crop needs are low. Circular Agronomics promotes treatment of raw manure and slurry. These processes end up with other kinds of organic by-products that will be also used for crop fertilization. It will be important to characterize these new products, to field test its behaviour when applied at soil in different environments and agricultural systems and to establish its suitability to be applied in certain moments within each crop cycle.

Short title (native language):

Idoneitat de diferents tipus de dejeccions i derivats com fertilitzants en cultius extensius

Short summary for practitioners (native language):

Els cultius tenen diferents necessitats de nutrients en diversos moments del seu cicle. Els nutrients en els fertilitzants, especialment els orgànics, es poden trobar en diverses formes i nivells de disponibilitat pels cultius. En la fertilització de cultius extensius es poden aplicar diferents tipus de dejeccions (fems, purins, ...), algunes en diferents moments, ja sigui abans de la sembra o en cobertora (amb el cultiu establert). La forma en què es troben els nutrients en cada tipus de dejecció les pot fer més idònies per ser aplicades en diferents moments del cicle de cultiu o de la rotació. En nitrogen (N) en els purins de porcí es troba majoritàriament (65-75 %) en forma amoniacal -ràpidament disponible pels cultius- i, per tant, és idoni per fer aplicacions quan les necessitats en N del cultiu són altes o ho seran en breu, per exemple en cobertora dels cereals d’hivern. En el cas dels fems, el N es troba principalment en forma orgànica. Serà disponible pel cultiu a mig-llarg termini, sovint algun any després de l’aplicació. És millor aplicar-lo abans de la sembra del cultiu, quan les necessitats són baixes. Circular Agronomics promou el tractament de les dejeccions. En aquests processos s’obtenen altres tipus de subproductes orgànics que també s’usaran en la fertilització dels cultius. Serà important caracteritzar-los, provar el seu comportament quan s’apliquen al sòl en diferents ambients i sistemes agrícoles i establir la seva idoneïtat per ser aplicats en determinats moments del cicle de cada cultiu.

Practice abstract 11

Short title (in English):

Smart grass species combinations for improving phosphorus uptake in pastures

Short summary for practitioners (in English):

Phosphorus (P) is one of the main nutrients for plants. Although most soils contain more than enough P to feed plants in principle, most of this P is chemically bound to soil particles and cannot be used by plants. For this reason, farmers need to apply relatively large amounts of P fertilizer. However, P fertilizer is expensive and the source of P fertilizer (rock phosphate) is limited, which means that we will need to be much more efficient with our P in the future. From studies conducted in nature, we know that combinations of plants can take up more P from the soil than single species. We are attempting to apply this principle in pastures: in a field experiment with a soil with a very low P status, we are testing whether smart combinations of grassland species can lead to a higher P use efficiency. We use four commonly used commercial grassland species (two types of Ryegrass; Timothy grass and Tall Fescue) that are very different in routing patterns to study which combinations take up most P and why this is. The field experiment will be running for two full years. We hope that at the end of the experiment we can give concrete advice to farmers on what combination of species to seed for a more P-efficient pasture system

Short title (native language):

Slimme combinaties van grassoorten om fosfaat opnamen in graslanden te verbeteren

Short summary for practitioners (native language):

Phosphorus (P) is een van de belangrijkste nutriënten voor planten. Alhoewel de meeste bodems in theorie meer dan genoeg P bevatten om een gewas te laten groeien, in principe, is het meeste van dit P chemisch gebonden aan bodemdeeltjes and kan daardoor niet gebruikt worden door planten. Daarom moeten boeren grote hoeveelheden P kunstmest toedienen. Maar kunstmest kost geld, en de bron van P kunstmest (rots fosfaat) is eindig. Daarom zullen we in de toekomst veel efficiënter om moeten gaan met P in de landbouw. Uit studies in natuurgebieden weten we dat combinaties van verschillende planten veel efficiënter P uit de bodem op kunnen nemen dan één planten soort. Hier proberen wij dit principe uit de natuur toe te passen in gemanaged grasland: in een veldexperiment op een bodem met een lage P status testen we of slimme combinaties van grassoorten tot een hogere P gebruiksefficientie kan leiden. We gebruiken vier gangbare commerciële grassoorten (twee soorten Engels raaigras; Rietzwenkgras Timoteegras) met heel verschillende bewortelingspatromen om be bestuderen welke combinaties de meeste P opnemen, en wat het mechanisme hierachter is. Het veldexperiment zal twee volle jaren lopen. We hopen dat we aan het einde van het experiment we concreet advies kunnen geven aan boeren over welke combinaties van soorten te zaaien om een meer P efficiënt grasland systeem te krijgen.

Practice abstract 12

Short title (in English):

N- and P-cycles in grassland-based farms

Short summary for practitioners (in English):

The nitrogen and phosphorus cycle are complex systems which are subject to various influencing variables and can be divided into several sub-systems. If one looks at the nitrogen and phosphorus cycle of agricultural farms, it can be seen that these usually have a low degree of closure. Through the sale of agricultural products such as milk or grain, nitrogen and phosphorus constantly leave the cycle. On the other hand, nitrogen and phosphorus are continuously introduced into the cycle through the purchase of seeds, fertilisers, feed stuff etc.
In order to close the nitrogen and phosphorus cycle on grassland-based farms to a higher degree, a voluntary programme for farmers was launched in the Lungau region in Austria. Within this programme, participating farms commit themselves to the exclusive use of their own fertilisers and feed stuff. Should it nevertheless be necessary to purchase inputs such as concentrated feed, for example, this must also be purchased from the region. In return, the farms receive a higher milk price from the dairy factory.
In Case Study 3, we assess the nitrogen and phosphorus cycles of these farms. First results show that especially the nitrogen cycle can be closed to a large extent. The phosphorus cycle cannot be closed as well, because the removal of phosphorus cannot be compensated by natural phosphorus sources on the farms.

Short summary for practitioners (native language):

Der Stickstoff- und Phosphorkreislauf sind komplexe Systeme welche verschiedenen Einflussgrößen unterliegen und in mehrere Teilkreisläufe unterteilt werden können. Betrachtet man den Stickstoff- und Phosphorkreislauf landwirtschaftlicher Betriebe, so zeigt sich, dass diese meist einen geringen Grad an Geschlossenheit aufweisen. Über den Verkauf landwirtschaftlicher Produkte wie zum Beispiel Milch oder Getreide verlässt ständig Stickstoff und Phosphor den Kreislauf. Auf der anderen Seite wird durch Zukäufe von Saatgut, Dünge- und Futtermitteln etc. laufend Stickstoff und Phosphor in den Kreislauf eingebracht.
Um den Stickstoff- und Phosphorkreislauf auf landwirtschaftlichen Betrieben in höherem Maße zu schließen, gibt es in der Region Lungau in Österreich ein freiwilliges Programm für Landwirtinnen und Landwirte. Bei diesem Programm verpflichten sich die teilnehmenden Betriebe zum ausschließlichen Einsatz von betriebseigenen Dünge- und Futtermitteln. Sollte der Zukauf von Betriebsmitteln wie zum Beispiel Kraftfutter dennoch notwendig sein, so muss dieses ebenfalls aus der Region bezogen werden. Im Gegenzug erhalten die Betriebe einen höheren Milchpreis von der Molkerei.
Im Rahmen der Case Study 3 werden die Stickstoff- und Phosphorkreisläufe dieser Betriebe untersucht. Erste Ergebnisse zeigen, dass vor allem der Stickstoffkreislauf weitgehend geschlossen werden kann. Der Phosphorkreislauf lässt sich weniger gut schließen, da die Abfuhr von Phosphor nicht durch natürliche Phosphorquellen auf den Betrieben ausgeglichen werden kann.

Practice abstract 13

Short title (in English):

Precision feeding systems in dairy farms

Short summary for practitioners (in English):

Feed cost are the highest costs in a dairy farm, and either overfeeding or underfeeding a dairy cow can have negative consequences. Precision feeding techniques allow to integrate data sensor information to accurately feed dairy cows. Circular Agronomics aims to evaluate a precision feeding system using feed intake, milk yield and composition, and body weight data to feed a concentrate supplemental feed in the milking parlour based on three different ingredients (soybean, corn, and wheat middlings) that provide different source of nutrients (crude protein, energy and fibre, respectively). We speculate that this feeding management can improve economic returns by feeding more accurately cows adjusting their daily requirements using a concentrate feed supplementation in the milking parlour. Furthermore, a reduction in the N excretion is expected since crude protein requirements will be daily adjusted. To evaluate the expected benefits of this precision feeding system a group of 28 dairy cows will be fed following a conventional or a precision feeding system and their diet digestibility will be assessed using faecal and urine spot sampling at different day intervals through a period of three days, and indigestible neutral fibre as internal marker.

Short title (native language):

Sistemas de alimentación de precisión en granjas de vacas lecheras

Short summary for practitioners (native language):

Los costes de alimentación son los más importantes en las explotaciones de vacuno lechero, y tanto una sobrealimentación como una alimentación por debajo de las necesidades tiene consecuencias negativas sobre los animales. Las técnicas de alimentación de precisión permiten integrar los datos recogidos por los sensores para alimentar a los animales de forma más concisa. En el proyecto Circular Agronomics se tiene como objetivo testar el sistema de alimentación de precisión utilizando datos de ingestión, cantidad y calidad de la leche, y peso vivo para dar un suplemento de pienso concentrado en la sala de ordeño usando 3 tipos diferentes de ingredientes (soja, maíz y tercerillas de trigo) que son fuente de distintos nutrientes (proteína, energía y fibra, respectivamente). Se especula que este manejo de la alimentación puede mejorar el retorno económico alimentando de forma más precisa a los animales ajustando sus necesidades diariamente. Para valorar estos beneficios que se esperan usando el sistema de alimentación de precisión, un grupo de 28 vacas lecheras se alimentaran siguiendo un sistema de alimentación convencional o de precisión y se valorará la digestibilidad de su dieta utilizando la técnica de muestreo puntual de heces y orina en distintos momentos del día durante 3 días consecutivos y usando la fibra neutro indigestible como marcador interno.

Practice abstract 14

Short title (in English):

Direct emissions modelling

Short summary for practitioners (in English):

A large number of emissions are generated by agricultural activities. Depending on the orientation of a farm, some emissions are more abundant and others less. Accordingly, a cattle farm will always produce higher methane emissions than an arable farm without livestock does. At the same time, the arable farm will be responsible for more nitrous oxide emissions than the cattle farm.
Within the framework of life cycle assessment, a distinction is made between direct and indirect emissions. Direct emissions are those that arise directly on the farm as a result of livestock farming, manure management and land management. Indirect emissions are the emissions from inputs. For example, the purchase of one kilogram of soy from Brazil has already caused certain emissions there due to the production of soy. Another example is the construction of buildings. Steel must be produced to build a cattle shed. The prerequisite for this in turn is the mining of ores. This ore mining also causes certain emissions.
In FarmLife, direct emissions from farms are modelled based on various models. These include emissions of phosphorus, heavy metals, nitrate, nitrous oxide, nitrogen oxides, ammonia and methane. As a result, FarmLife can be used to point out possible optimization potentials with regard to emission reduction. Results from cattle farms have shown that the greatest potential for reducing emissions lies in the areas of feeding/concentrate use and in the adaptation of the livestock density to the farm's own area.

Short title (native language):

Direkte Emissionsmodellierung

Short summary for practitioners (native language):

Im Rahmen landwirtschaftlicher Tätigkeiten entsteht eine Vielzahl von Emissionen. Je nach Ausrichtung eines landwirtschaftlichen Betriebs treten manche Emissionen stärker auf und andere schwächer. Dementsprechend wird ein rinderhaltender Betrieb höhere Methanemissionen verursachen als ein viehloser Ackerbaubetrieb. Gleichzeitig muss jedoch der Ackerbaubetrieb mehr Lachgasemissionen verantworten als der rinderhaltende Betrieb.
Im Rahmen der Ökobilanzierung wird zwischen direkten und indirekten Emissionen unterschieden. Direkte Emissionen sind jene, die durch die Tierhaltung, das Wirtschaftsdüngermanagement und die Bewirtschaftung der Flächen direkt am Betrieb entstehen. Unter indirekten Emissionen versteht man die Emissionen aus den Vorleistungen. Beispielsweise hat der Zukauf von einem Kilogramm Soja aus Brasilien aufgrund der Produktion dort bereits gewissen Emissionen verursacht. Zum Bau eines Rinderstalls muss Stahl erzeugt werden. Die Voraussetzung dafür ist wiederum der Abbau von Erzen. Auch dieser Erzabbau hat gewisse stoffliche Emissionen zur Folge.
In FarmLife werden auf Basis verschiedener Modelle die direkten Emissionen landwirtschaftlicher Betriebe modelliert. Dazu zählen die Emissionen von Phosphor, Schwermetallen, Nitrat, Lachgas, Stickoxiden, Ammoniak und Methan. Im Ergebnis kann mittels FarmLife auf mögliche Optimierungspotentiale im Hinblick auf Emissionsreduktion hingewiesen werden. Aus bisherigen Ergebnissen rinderhaltender Betriebe zeigt sich, dass vor allem in den Bereichen Fütterung – Kraftfuttereinsatz und in der Anpassung des Tierbestandes an die eigene Fläche die größten Potentiale liegen um Emissionen zu reduzieren.

Practice abstract 15

Short title (in English):

Influence of feeding strategies on methane emissions of dairy cows

Short summary for practitioners (in English):

Methane is a greenhouse gas which is produced in the digestion process of ruminants amongst others. In times of global warming, it is an aim to find strategies how to reduce methane emissions of ruminants. Thus, gaseous emissions of dairy cows (methane, carbon dioxide and ammonia) are measured in two respiration chambers at AREC Raumberg-Gumpenstein (Austria). Methane is produced in the course of fibre degradation in the rumen. Thus, altering the fibre content of dairy cows' rations by changing the forage: concentrates ratio may be a strategy to reduce methane emissions. However, high proportions of concentrates in the rations might have negative side-effects on the health of the cows (e.g. higher risk of metabolic diseases). Thus, the aim of this project is to evaluate the effect of the forage: concentrates ratio of the ration on the gaseous emissions of dairy cows. Besides the determination of the daily amounts of gaseous emissions, it is also aimed to test the efficiency of gaseous emissions (e.g. g CH4/kg milk production). The results of this study will show which feeding strategy would be the most efficient with respect to both feed intake, milk production and methane emissions of dairy cows. In the next years and decades, prevention of (greenhouse gas) emissions will become more and more a topic in agriculture and especially in animal husbandry. The final results of this study should help dairy farmers to find their optimal way to achieve an economically and ecologically efficient milk production.

Short title (native language):

Einfluss der Fütterungsstrategie auf Methanemissionen von Milchkühen

Short summary for practitioners (native language):

Methan ist ein Treibhausgas, welches unter anderem im Verdauungsprozess von Wiederkäuern entsteht. In Zeiten des Klimawandels werden Strategien gesucht, mit welchen die Methanemissionen reduziert werden können. Daher werden in zwei Respirationskammern an der HBLFA Raumberg-Gumpenstein (Österreich) die gasförmigen Emissionen von Milchkühen (Kohlendioxid, Methan und Ammoniak) gemessen. Methan entsteht im Zuge der Faserverdauung im Pansen. Daher ist die Veränderung des Fasergehalts in der Ration von Milchkühen durch Veränderung des Grundfutter : Kraftfutter-Verhältnisses eine mögliche Maßnahme, Methanemissionen zu reduzieren. Hohe Kraftfutteranteile in Milchviehrationen können jedoch negative Nebeneffekte auf die Gesundheit der Tiere haben (z.B. höheres Risiko von Stoffwechselkrankheiten). Daher ist es das Ziel dieses Projekts, den Einfluss des Grundfutter : Kraftfutter-Verhältnisses der Ration auf die gasförmigen Emissionen der Milchkühe zu untersuchen. Neben der Ermittlung der täglichen Methanemissionen wird auch die Effizienz der Methanproduktion analysiert (z.B. g CH4/kg produzierter Milch). Die Ergebnisse diese Projekts werden zeigen, welche Fütterungsstrategie die effizienteste in Bezug auf Futteraufnahme, Milchproduktion und Methanemissionen ist. In den nächsten Jahren und Jahrzehnten wird die Vermeidung von (Treibhausgas-) Emissionen mehr und mehr zu einem Thema in der Landwirtschaft und im besonderen in der Viehwirtschaft werden. Die Endergebnisse dieser Studie sollen den Milchbauern helfen, ihren optimalen Weg zur Erreichung einer ökonomisch und ökologisch effizienten Milchproduktion zu finden.

Practice abstract 16

Short title (in English):

"Farmlife" as management tool to reduce emissions on farms

Short summary for practitioners (in English):

Emissions on farms can be comprehensively calculated in FarmLife through the combination of nutrient-flow-models with Life Cycle Analysis (LCA)-data. The result, however, not only shows the overall environmental impacts but also their origin from different product or input groups. As the effects of the infrastructure are very clearly splitted from the use of feed, fertilisers and pesticides, very precise recommendations for farm development can be given to the farm managers. These recommendations are also linked to economic aspects in the assessment of eco-efficiency. Within the framework of the Lungau case study, FarmLife was used on 22 farms in 2018 and on 17 farms in 2019, where it now has a major impact on the planning of farm objectives. On over 100 other reference farms in Austria, the effect of FarmLife in reducing emissions by changing the intensity in the direction of site-adapted agriculture is already evident. Circular Agronomics benefits from using the tool in several work packages.

Short title (native language):

Reduktion von Emissionen auf bäuerlichen Betrieben durch den Einsatz von FarmLife

Short summary for practitioners (native language):

Emissionen auf landwirtschaftlichen Betrieben können in FarmLife durch die Verbindung von Fachmodellen und betriebliche Vorleistungen in einer LCA umfassend dargestellt werden. Im Ergebnis zeigen sich aber nicht nur die gesamten Umweltwirkungen, sondern auch deren Herkunft aus verschiedenen Betriebsbereichen bzw. Input-Gruppen. Da sich die Wirkungen der Infrastruktur ganz deutlich vom Einsatz von Futtermitteln, Düngern und Pflanzenschutzmitteln abhebt, können den Betrieben sehr genaue Empfehlungen für die Betriebsentwicklung gegeben werden. Diese Empfehlungen verbinden sich in der Bewertung der Ökoeffizienz auch mit der Wirtschaftlichkeit. Im Rahmen der Case-Study Lungau wurde FarmLife im Jahr 2018 auf 22 und im Jahr 2019 auf 17 Bauernhöfen eingesetzt und hat dort nun große Wirkung auf die Planung der Betriebsziele. Auf über 100 anderen Referenzbetrieben in Österreich zeigt sich bereits die Wirkung von FarmLife zur Reduktion von Emissionen durch die Veränderung des Betriebskonzeptes in die Richtung einer standortangepassten Landwirtschaft. CircularAgronomics profitiert vom Einsatz des Tools in mehreren Arbeitspaketen.

Practice abstract 17

Short title (in English):

Dynamic chambers for gaseous emissions monitoring

Short summary for practitioners (in English):

Livestock emissions represent more than 10% of the total GHG emissions and more than 85% of the total NH3 emissions. Among other sources, manure storage and its field application are the most contributing to these emissions. The European Commission is strongly betting on this aspect and will promote measures to reduce emissions in the coming years, such as storage systems sealing. The first step to reduce emissions would be to determine the hot spots and the amount of emissions generated in each one. However, the determination of these emissions is not an easy task. For this purpose, there are several sampling devices such as the dynamic chambers (Lindvall hood and wind tunnels). These devices can be used in both liquid and solid substrates, they are movable, allow to take samples accurately under controlled conditions, at constant flows, and a subsequent characterisation of these samples. Within the Circular Agronomics project dynamic chambers are being used to determine emissions on pig and cow manure storage, after manure application in agronomic fields and on the treatment processes that are being developed in the framework of the project, with the aim of making nutrient balances in an appropriate manner and to apply minimisation strategies.

Short title (native language):

Cámaras dinámicas para la monitorización de emisiones gaseosas

Short summary for practitioners (native language):

Las emisiones de la ganadería representan más del 10% del total de las emisiones GEI y más del 85% de las emisiones totales de NH3. Entre otras fuentes, el almacenamiento de los purines en balsas y su aplicación en el campo son las que más contribuyen a estas emisiones. La Unión Europea está apostando fuerte en este aspecto y promoverá medidas para su reducción en los próximos años, como el sellado de los sistemas de almacenamiento. El primer paso para la reducción de emisiones sería determinar exactamente los puntos calientes y la cantidad generada en cada uno de ellos. Pero la determinación de las emisiones generadas no es una tarea fácil. Para ello existen diferentes dispositivos de muestreo entre los que se encuentran las cámaras dinámicas (campana Lindvall y túneles de viento). Estas cámaras pueden emplearse tanto en sustratos líquidos como sólidos, son móviles, y permiten la toma precisa de muestras de emisiones en condiciones controladas, a caudal constante, y una posterior caracterización de dichas muestras. En el proyecto Circular Agronomics se emplean estas cámaras para la determinación de emisiones en el almacenaje de los purines de cerdo y vaca, tras su aplicación en el campo y en los procesos de tratamiento de estos que se están desarrollando en el marco del proyecto con el objetivo de realizar los balances de nutrientes de una forma adecuada y aplicar estrategias para su minimización

Practice abstract 18

Short title (in English):

Solid-liquid separation of manure

Short summary for practitioners (in English):

Manure management represents an important part of the total cost of a livestock farm due to the manure high water content (more than 90%), which makes difficult its transport to other zones. The use of solid-liquid separators is an effective tool that allows a nutrient redistribution, improving the management capability. By using these systems, a solid fraction (SF), with high solids content, and a liquid fraction (LF), aqueous solution with dissolved and suspended material, can de obtained. In the SF more phosphorus (P) than nitrogen (N) is concentred thus increasing the N/P ration in the LF. Therefore, when fertilising using the LF, higher N amount is incorporated without exceeding the P needs of the crop. The solid-liquid separators can be classified in gravity, pressure and centrifugation systems (the most efficient). Separation yield to the SF ranges between 15-45% for N and 20-80% for P, and it depends on the technology and/or the use of additives, manure composition and age, flow stability, etc. Operating costs range between 1.96-2.34 euros per kg of N and 4.96-4.43 euros per kg of P, and they are highly dependents on the kind of separator and the working flow, among other factors. Within the Circular Agronomics project, screw press and centrifuges are being used, followed by post-treatments of the resulting fractions for their valorisation as organic and inorganic fertilizers.

Short title (native language):

Separación sólido-líquido de purines

Short summary for practitioners (native language):

La gestión de los purines supone una parte importante de los costes de una explotación ganadera debido a la elevada humedad de estos (mayor al 90%), que dificulta su transporte a otras zonas. El uso de separadores sólido-líquido es una herramienta eficaz que permite una redistribución de los nutrientes, mejorando la capacidad de gestión. Estos sistemas permiten obtener una fracción sólida (FS), con un alto contenido en sólidos, y una fracción líquida (FL), solución acuosa con elementos disueltos y en suspensión. En la FS se concentra más fósforo (P) que nitrógeno (N) incrementándose la relación N/P en la FL. Por tanto, al fertilizar con FL, se incorpora una mayor cantidad de N sin exceder las necesidades de P del cultivo. Los separadores se pueden clasificar en sistemas por gravedad, por presión o por centrifugación (los más eficaces). Los rendimientos de separación o exportación a la FS oscilan entre un 15-45% para el N y un 20-80% para el P, y dependen de la tecnología utilizada y/o el uso de aditivos, de la composición y edad del purín, de la estabilidad del caudal de entrada, etc. Los costes de operación oscilan entre 1,96-2,34 euros por kg de N y 4,96-4,43 euros por kg de P. Estos costes son altamente dependientes de la tecnología utilizada y del caudal de trabajo, entre otros factores. En el proyecto Circular Agronomics se están empleando separadores sólido-líquido por presión y centrifugación, seguidos de postratamientos de las facciones resultantes para su valorización como fertilizantes orgánicos e inorgánicos

Practice abstract 19

Short title (in English):

Solar drying of manure

Short summary for practitioners (in English):

Livestock manure is a semi-liquid faecal product with about 3-8% of dry matter content, and it is usually spread on agricultural fields in order to use the naturally present nutrients. Its high-water content and the difficulty of applying it when needed led to nutrient losses, mainly in the form of leaching and gaseous emissions. These losses can be up to 50% in some cases. By means of fixing ammonium salts and reducing water content it is possible to obtain a dried product that remains stable for a long time, thus allowing to spread it according to crops needs and avoiding leaching of soluble compounds and gases volatilisation. Solar drying brings together calorific power and solar irradiation to dry manure and, by using a mixing and stirring system, it is possible to obtain a stabilised solid fraction similar to compost. The final product has a dry matter content higher than 65%. This is a renewable technology and it does not produce residual streams, with losses less than 1%. It is estimated an operational cost of about 4€/m3, considering 10 years of depreciation. The results obtained so far are very positive, with high solar irradiation only 10 days were needed to dry manure up to 65% of dry matter.

Short title (native language):

Secado solar de purines

Short summary for practitioners (native language):

El purín es un producto semilíquido con materia orgánica fecal de origen ganadero, que normalmente se encuentra en una concentración de un 3-8%, y suele aplicarse directamente al terreno para aprovechar el valor agronómico de los nutrientes presentes de forma natural. Su gran contenido en agua y la dificultad de aplicarlo en el momento preciso da lugar a una pérdida de nutrientes en forma de lixiviados y emisiones gaseosas, principalmente. Esta pérdida puede ser superior al 50% en algunos casos. Mediante la fijación de las sales amoniacales y la reducción del contenido de agua se consigue obtener un producto concentrado seco que se mantiene estable por mucho tiempo, pudiendo hacer la aplicación en el momento requerido y evitando la percolación en las capas freáticas de los componentes solubles y la volatilización de los gases. El secado solar de purines combina el poder de calorífico y la radiación solar para su deshidratación y, mediante un sistema de mezcla y agitación, se consigue estabilizar la fracción seca de forma similar a un compost. El producto obtenido tiene una sequedad superior al 65%. La tecnología es renovable en su concepto y no genera corrientes residuales, con pérdidas inferiores al 1%. Se estima que el tratamiento tiene un coste de 4€/m3, considerando la amortización del sistema a 10 años. Los resultados obtenidos por el momento son bastante esperanzadores, en momentos de fuerte radiación solar el secado se puede producir en 10 días y se han efectuado visitas con ganaderos de la zona interesados para su implantación a escala real, su interés ha sido notable debido a su simplicidad, facilidad de uso y calidad del material obtenido.

Practice abstract 20

Short title (in English):

Microfiltration of slurry/digestate

Short summary for practitioners (in English):

Why is it useful to microfilter livestock slurry and digestates?
Microfiltration is carried out downstream of conventional solid-liquid separation, on the clarified fraction, using a new simple equipment such as the microfilter specially developed by Saveco WAMgroup.
A microfiltered phase is obtained from which particles with a diameter greater than 50 microns (equivalent to three white blood cells) are almost completely excluded. The microfiltered fraction, which generally represents the largest portion of slurry or digestate entering the treatment, is pumped easily and does not clog up nozzles or drippers. Moreover, it contains most of the nitrogen in ammoniacal form, which is ready-to-use for plant nutrition.
The optimal agronomic use of the microfiltered fraction is then the distribution on growing crops, in order to increase the nutrient use efficiency as much as possible and saving mineral fertilisers. In the Circular Agronomics project microfiltration tests and the use of microfiltered digestate in fertigation, by means of Netafim drip lines buried 25 cm deep (SDI – subsurface drip irrigation) are being conducted at CAT Correggio biogas farm (Emilia-Romagna region, Italy).
The first year of experimentation was successful both in terms of the technical feasibility of the proposed innovative solution and for the excellent silage maize yields, obtained in combination with high nutrient use efficiency. In 2020 the trials will be repeated on sorghum.

Short title (native language):

Microfiltrazione di liquami zootecnici/digestati

Short summary for practitioners (native language):

Perché può risultare utile microfiltrare liquami zootecnici e digestati?
La microfiltrazione viene attuata a valle della separazione solido-liquido convenzionale, sulla frazione chiarificata, facendo uso di una nuova e semplice attrezzatura come il microfiltro appositamente sviluppato da Saveco WAMgroup.
Si ottiene una fase microfiltrata dalla quale sono state quasi completamente escluse le particelle con diametro superiore ai 50 micron (equivalenti a tre globuli bianchi del sangue). La frazione microfiltrata, che generalmente rappresenta la quota maggiore del liquame o digestato in ingresso al trattamento, viene pompata facilmente e non intasa ugelli o gocciolatori. Inoltre contiene la maggior parte dell’azoto in forma ammoniacale, che è prontamente disponibile per la nutrizione vegetale.
La modalità di utilizzo agronomico ottimale della frazione microfiltrata è quindi la distribuzione sulle coltivazioni in atto, in modo tale da incrementare più possibile l’efficienza d’uso dei nutrienti e risparmiare concimi di sintesi. Nel progetto Circular Agronomics, presso l’azienda CAT Correggio con impianto di biogas (Emilia-Romagna, Italia), si stanno conducendo delle prove di microfiltrazione e utilizzo del digestato microfiltrato in fertirrigazione, per mezzo di ali gocciolanti Netafim interrate a 30 cm di profondità (subirrigazione a goccia – SDI).
Il primo anno di sperimentazione ha avuto successo sia in termini di praticabilità tecnica della soluzione innovativa proposta che per le ottime rese colturali di mais insilato, ottenute in abbinamento e elevata efficienza d'uso dei nutrienti. Nel 2020 le prove saranno ripetute su sorgo.

Practice abstract 21

Short title (in English):

Vacuum degasification of ammonia from manure

Short summary for practitioners (in English):

Manure is frequently used as an organic fertilizer in agriculture, delivering organic material for the soil and nitrogen which is an important nutrient for plants. However, the seasonal application time of manure is often not in line with the actual nitrogen demand of the plants. Consequently, an undesired loss of nitrogen for the plants due to emissions to the groundwater (nitrate) or to the atmosphere (ammonia and/or nitrous oxide) occurs and poses serious environmental problems in regions with high rate manure application.
In order to decouple the supply of organics and nitrogen contained in the manure, Circular Agronomics designs and constructs a pilot plant for vacuum degasification to recover nitrogen as ammonia. The pilot plant will produce a "nitrogen depleted manure" ready to serve as a soil conditioner. Circular Agronomics aims to achieve a nitrogen recovery rate between 80% and 90% of the nitrogen which was originally present as ammonium in the manure. The process will be optimized by varying vacuum pressure, chemical dosing for raising pH, and temperature conditions. In a subsequent process step of the pilot plant, the recovered ammonia gas will be used to produce a ready-to-use nitrogen fertilizer.

Short title (native language):

Vakuumentgasung von Ammoniak aus Gülle

Short summary for practitioners (native language):

Gülle wird häufig als Wirtschaftsdünger in der Landwirtschaft genutzt. Sie liefert sowohl organisches Material für den Boden als auch Stickstoff, der ein wichtiger Pflanzennährstoff ist. Oft stimmt jedoch die saisonale Ausbringung der Gülle nicht mit dem Zeitpunkt des tatsächlichen Stickstoffbedarfs der Pflanzen überein. Dies führt zu einem unerwünschten Verlust des Stickstoffs für die Pflanzen durch Emissionen ins Grundwasser (Nitrat) oder in die Atmosphäre (Ammoniak und/oder Lachgas). Besonders in Regionen mit einem hohen Gülleaufkommen und einer hohen Ausbringungsrate der Gülle kann es zu starken Umweltbelastungen kommen.
Um die Zufuhr des organischen Materials aus der Gülle für den Boden von der Stickstoffzufuhr für die Pflanzen zu entkoppeln, wird in Circular Agronomics eine Pilotanlage entwickelt. Hier wird über eine Vakuumentgasung Ammoniakgas aus der Gülle zurückgewonnen. Zudem produziert die Pilotanlage eine "stickstoffabgereicherte Gülle", die als Bodenverbesserer eingesetzt werden kann. Cirular Agronomics zielt darauf ab, zwischen 80 % und 90 % des Stickstoffs, der ursprünglich als Ammonium vorlag, aus der Gülle zurückzugewinnen. Um den Prozess zu optimieren, werden verschiedene Versuche mit unterschiedlichen Drücken im Vakuumbereich sowie bei unterschiedlichen pH-Werten und Temperaturbereichen durchgeführt. In einem anschließenden Prozessschritt wird das zurückgewonnene Ammoniak zur Herstellung eines direkt einsetzbaren Stickstoffdüngers weiterverwertet.

Practice abstract 22

Short title (in English):

Effect of genotype and diet composition on efficiency in milk production

Short summary for practitioners (in English):

Each agricultural production system should aim to produce food with highest efficiency. In this context, efficiency can have different meanings: optimal utilization of nutrients (nutritional efficiency), realization of high incomes (economic efficiency) or minimization of environmental impacts (ecological efficiency). A project at AREC Raumberg-Gumpenstein aims to study each of these three aspects of efficiency. In this study, effect of genotype (Holstein Friesian_conventional breeding, Holstein Friesian_NewZealand, Holstein Friesian_lifetime performance breeding and Simmental) and diet composition (indoor feeding with 0, 20 and 40% concentrates proportion in whole diet) on feed intake, milk yield and efficiency of milk production is examined. This project will lead to valuable results on nutritional and economic efficiency. Furthermore, within the Circular Agronomics project, ecological efficiency is analysed by measuring methane emissions of dairy cows in respiration chambers. The results will allow conclusions, which genotype, which diet composition and which combination of genotype and diet composition will lead to highest efficiency both from an economic and an ecological point of view in a certain geographic region. Because, besides a high efficiency, it is also important that production strategy is appropriate for a certain geographic region to avoid indirect agricultural emissions (e.g. caused by transport of feeds).

Short title (native language):

Einfluss von Genotyp und Rationszusammensetzung auf die Effizienz der Milchproduktion

Short summary for practitioners (native language):

Das Ziel jedes landwirtschaftlichen Produktionssystems sollte sein, mit höchster Effizienz Lebensmittel zu produzieren. Effizienz kann die bestmögliche Ausnutzung von Nährstoffen (Nährstoffeffizienz), die Erzielung hoher Erlöse (ökonomische Effizienz) oder die Minimeriung von Umweltwirkungen bedeuten (ökologische Effizienz). In einem Projekt an der HBLFA Raumberg-Gumpenstein werden alle drei Bereiche der Effizienz untersucht. Es wird erhoben, welchen Einfluss verschiedene Genotypen von Kühen (Holstein_Hochleistung, Holstein_Neuseeland, Holsten_Lebensleistung und Fleckvieh) und verschiedene Rationszusammensetzungen (Stallfütterung mit 0, 20 und 40 % Kraftfutteranteil in der Gesamtration) auf Futteraufnahme, Milchleistung und Effizienz der Milchproduktion haben. Die Auswertung des Projekts wird wertvolle Aussagen zur Nährstoffeffizienz und ökonomischen Effizienz liefern. Um auch die ökologische Effizienz der Milchproduktion bewerten zu können, werden im Rahmen des CircularAgronomics-Projekts Methanemissionen der Kühe in Respirationskammern gemessen. Aus den Ergebnissen lässt sich daher ableiten, welcher Genotyp, welche Rationszusammensetzung und welche Kombination aus Genotyp und Rationszusammensetzung sowohl aus ökonomischer als auch aus ökologischer Sicht die höchste Effizienz aufweist und somit für eine bestimmte Region am effizientesten ist. Denn, neben einer hohen Effizienz ist es auch wichtig, dass die Produktionsstrategie zum jeweiligen Standort passt, damit indirekte, landwirtschaftliche Emissionen (z.B. durch Transporte von Futtermitteln) vermieden werden können.

Practice abstract 23

Short title (in English):

Ammonium sulfate solution from manure

Short summary for practitioners (in English):

Ammonium-sulfate is a product from the process of Ammonia recovery from exhaust gas. Sources of the Ammonia gas can be Ammonia removal from manure, from biogas digestate, sewage sludge or the exhaust gas of biological waste treatment or animal husbandry. Ammonia is scrubbed with a sulphuric acid solution. Ammonium-sulfate can be used as liquid mineral fertilizer. N concentrations should match fertilizer recommendations, e.g. 5% N according to the German fertilizer law. Prices that can be generated by selling the Ammonium-sulfate fertilizer depend on the N-concentration, the impurities (such as dust or other particles) and the pH (>5). As the fertilizer contains a lot of water (around 75% when N is around 5%), its handling is rather costly because transport and storage require a big volume. For farmers, ammonium-sulfate is of interest because they can cover both, the N and S demand. Both operators and farmers benefit, when N concentrations are as high as possible. Especially operators of Ammonia scrubbers should demand high N concentrations from scrubber suppliers in their ammonium-sulfate. In addition, many plants operate 365 days per year. Consequently, storage capacity for Ammonium-sulfate during the non-fertilizer season must be considered.

Short summary for practitioners (native language):

Ammoniumsulfat-Lösung (ASL) ist ein Produkt, welches durch Ammoniumabreicherung entsteht. Ammonium kann zum Beispiel aus Gülle, Gärrest, Klärschlamm gestrippt werden oder es ist in der Abluft von Ställen oder biologischen Abfallbehandlungsanlagen enthalten. Das Ammoniak wird mit Hilfe von Schwefelsäure aus der Abluft gewaschen, und es entsteht eine Ammoniumsulfat-Lösung, die als mineralischer Flüssigdünger eingesetzt werden kann. Die N-Gehalte sollten die ortsüblichen Mindestgehalte der Düngegesetze einhalten, in Deutschland sind dies z.B. 5%N. Der Wert der Lösung orientiert sich am N-Gehalt (preisfördernd) sowie an Verunreinigungen (preissenkend) und dem pH, der über 5 liegen sollte. Die Lösung enthält relativ viel Wasser (etwa 75%,wenn der N-Gehalt 5% beträgt). Deshalb ist der Transport und Lagerung der Lösung kostenintensiv, da das Volumen und Gewicht im Verhältnis zur Nährstoffkonzentration relativ hoch ist. Für Landwirte ist ASL interessant, da sie sowohl den N- als auch den Schwefelbedarf der Kulturen abdecken kann. Sowohl ASL-Produzenten als auch ASL-Anwender profitieren davon, dass der N-Gehalt möglich hoch ist. Anlagenbetreiber sollten bereits bei der Auslegung und Spezifizierung der Ammoniakwäsche Vorgaben machen, dass die produzierte ASL mindestens 5% N enthält. Darüber hinaus sollten sich Anlagenbetreiber darüber im Klaren sein, dass ASL nur während der Düngesaison Absatz findet, für die restliche Zeit sind Lagerkapazitäten vorzuhalten.

Practice abstract 24

Short title (in English):

Ammonium hydrogen carbonate

Short summary for practitioners (in English):

Ammonium-hydrogencarbonate could be produced from Ammonia recovery from liquids that contain also a high carbonate concentration, such as manure and biogas digestate. Ammonia is evaporated by vacuum or stripping. Ammonium-hydrogencarbonate can be used as liquid mineral fertilizer. N concentrations should match fertilizer recommendations. Prices that can be generated by selling the Ammonium-hydrogencarbonate fertilizer depend on the N-concentration, the impurities (such as dust or other particles) and the pH. As the fertilizer contains a lot of water, its handling is rather costly because transport and storage require a big volume. For farmers, Ammonium-hydrogencarbonate must be incorporated into the soil immediately after field application to avoid Ammonia emissions. Both operators and farmers benefit, when N concentrations are as high as possible. Especially operators of Ammonia evaporation by vacuum should demand high N concentrations from degasifier suppliers. In addition, many plants operate 365 days per year. Consequently, gas tight storage capacity for Ammonium-hydrogencarbonate during the non-fertilizer season must be considered.

Short title (native language):

Ammoniumhydrogencarbonat-Lösung

Short summary for practitioners (native language):

Ammoniumhydrogencarbonat-Lösung (ACL) ist ein Produkt, welches durch Ammoniumabreicherung entsteht. Ammoniak und Kohlendioxid können zum Beispiel aus Gülle und Gärrest gestrippt werden - auch unter Vakuum. Das Ammoniak wird mit Hilfe von Hydrogencarbonat-lösung aus der Abluft gewaschen: Es entsteht ACL, die als mineralischer Flüssigdünger eingesetzt werden kann. Die N-Gehalte sollten die ortsüblichen Mindestgehalte der Düngegesetze einhalten.Der monetäre Wert der Lösung orientiert sich am N-Gehalt (preisfördernd) sowie an Verunreinigungen (preissenkend) und dem pH, der etwa 7-8 betragen sollte. Die Lösung enthält relativ viel Wasser. Deshalb ist der Transport und Lagerung der Lösung kostenintensiv, da das Volumen und Gewicht im Verhältnis zur Nährstoffkonzentration relativ hoch ist. Für Landwirte ist ACL Produkt, das sofort nach Ausbringung eingearbeitet werden muss, um Ammoniakemissionen zu vermeiden. Sowohl ACL-Produzenten als auch ACL-Anwender profitieren davon, dass der N-Gehalt möglich hoch ist. Anlagenbetreiber sollten bereits bei der Auslegung und Spezifizierung der Ammoniakwäsche Vorgaben machen, dass die produzierte ACL möglichst hoch ist. Darüber hinaus sollten sich Anlagenbetreiber darüber im Klaren sein, dass ACL nur während der Düngesaison Absatz findet, für die restliche Zeit sind gasdichte Lagerkapazitäten vorzuhalten.

Practice abstract 25

Short title (in English):

Recycling potential of food waste and wastewater from the food industry focusing on carbon

Short summary for practitioners (in English):

Especially in food waste and wastewater from the food industry, the organic carbon content is usually quite high compared to municipal wastewater. Thus, recycling or further use of those waste and wastewater streams might be profitable. As long as the waste cannot be reused or processed further to food or fodder additives, there are two options for carbon utilization: (1) the biomass is digestated to biogas for energy production and (2) the biomass is reused as soil conditioner. It might be even favorable to combine both reuse purposes. In doing so, easly degradable organic compounds will be utilized in anaerobic digestion for biogas production and the remaining, more difficult to degrade, organic compounds contained in the digestate can enhance the organic fraction of the soil.
In Circular Agronomics, different organic waste and wastewater streams from food and agricultural industry are screened. Therefore, the updated BREF document (2019) "Best available techniques (BAT) reference document for the food, drink and milk industries" serves as a basis. In this document, a variety of organic wastewater streams are characterized. In addition, publications and results from other research projects as well as data bases available in the internet are evaluated.

Short title (native language):

Wiederverwertungspotential von Kohlenstoff aus Speiseabfällen und Abwässern aus der Lebensmittelindustrie

Short summary for practitioners (native language):

Der organische Kohlenstoffgehalt in Speiseabfällen und Abwässern aus der Lebensmittelindustrie ist gewöhnlich relativ hoch im Vergleich zu kommunalem Abwasser. Deshalb kann die Wiederverwertung dieser Stoffströme von Vorteil sein. Solange diese Stoffströme nicht weiter als Nahungsmittelzusätze oder Futtermittel genutzt oder dazu weiterverarbeitet werden, gibt es zwei weitere Optionen für deren Verwertung: (1) die in den Stoffströmen enthaltene Biomasse wird zur Biogasproduktion eingesetzt oder (2) als Bodenverbesserer genutzt. Die Kombination beider Optionen kann noch mehr Vorteile liefern. Hierbei werden nämlich die leicht abbaubaren organischen Verbindungen in einer anaeroben Behandlung zu Biogas umgesetzt und der Gärrest, in dem nachwievor organische Verbindungen enthalten sind, kann weiter als Bodenverbesserer eingesetzt werden.
In Circular Agronomics werden verschiedene organische Abfälle und Abwasserströme diesbezüglich betrachtet. Hierfür wird u. a. das neue BREF-Dokument (2019) "Best available techniques (BAT) reference document for the food, drink and milk industries" genutzt, in dem zahlreiche Abwässer aus der Nahrungsmittelindustrie charakterisiert sind. Zusätzlich werden wissenschaftliche Publikationen, die Ergebnisse anderer Forschungsprojekte und im Internet verfügbare Datenbanken in die Auswertung miteinbezogen.

Practice abstract 26

Short title (in English):

Recycling potential of food waste and wastewater focusing on nitrogen

Short summary for practitioners (in English):

In Circular Agronomics, different organic waste and wastewater streams from food and agricultural industry are screened in terms of their recycling potential. Therefore, the BREF document (2019) "Best available techniques (BAT) reference document for the food, drink and milk industries" serves as a basis. In this document, a variety of organic wastewater streams are characterized. In addition, publications and results from other research projects as well as databases available in the internet are evaluated.

Especially protein rich food waste and wastewaters from the food industry contain quite high nitrogen contents compared to other food waste and wastewaters. The preparative screening revealed for nitrogen, that in particular, wastewaters from sugar manufacturing, animal feed production, dairies and meat processing contain relatively high nitrogen contents. Furthermore, compared to municipal wastewater, the carbon content is quite high as well. Thus, recycling or further use of those waste and wastewater streams might be profitable.

Circular Agronomics aims to classify the waste(water) streams and to determine the availability and regional distribution of the most interesting streams. In doing so, the small and medium enterprises (SME) might use this information to further extend their business models.

Short title (native language):

Wiederverwertungspotential von Stickstoff aus Speiseabfällen und Abwässern aus der Lebensmittelindustrie

Short summary for practitioners (native language):

In Circular Agronomics werden verschiedene organische Abfälle und Abwasserströme in Bezug auf ihr Wiederverwertungspotential betrachtet. Hierfür wird u. a. das neue BREF-Dokument (2019) "Best available techniques (BAT) reference document for the food, drink and milk industries" genutzt, in dem zahlreiche Abwässer aus der Nahrungsmittelindustrie charakterisiert sind. Zusätzlich werden wissenschaftliche Publikationen, die Ergebnisse anderer Forschungsprojekte und im Internet verfügbare Datenbanken in die Auswertung miteinbezogen.

Insbesondere proteinreiche Speiseabfälle und Abwässer aus der Lebensmittelindustrie beinhalten einen relativ hohen Stickstoffgehalt im Vergleich zu anderen Speiseabfällen und Abwässern. Eine erste grobe Analyse verschiedener Stoffströme zeigte, dass vor allem in Abwässern aus der Zuckerherstellung, der Tierfutterherstellung, der Molkerei und der Fleischverarbeitung relativ hohe Stickstoffgehalte zu finden sind. Zudem sind die Kohlenstoffgehalte im Vergleich zu kommunalen Abwässern ebenfalls relativ hoch, so dass sich eine Wiederverwertung dieser Stoffströme in mehrfacher Hinsicht lohnt.

Circular Agronomics zielt darauf ab, Abfall- und Abwasserströme zu klassifizieren und die regionale Verfügbarkeit der interesanntesten Ströme zu bestimmen. Diese Informationen sollen den klein- und mittelständischen Unternehmen (KMUs) zur Verfügung gestellt werden, damit sie ihre Geschäftsmodelle weiter ausbauen können.

Practice abstract 27

Short title (in English):

Recycling potential of food waste and wastewater focusing on phosphorus

Short summary for practitioners (in English):

In Circular Agronomics, different organic waste and wastewater streams from food and agricultural industry are screened. Therefore, the BREF document (2019) "Best available techniques (BAT) reference document for the food, drink and milk industries" serves as a basis. In this document, a variety of organic wastewater streams are characterized. In addition, publications and results from other research projects as well as databases available in the internet are evaluated.
The preparative screening revealed for phosphorus, that in particular, wastewaters resulting from oilseed processing, soybean processing, meat processing and animal feed production contain relatively high phosphorus contents. Furthermore, compared to municipal wastewater, the carbon content is quite high as well. Thus, recycling or further use of those waste and wastewater streams might be profitable.
Circular Agronomics aims to classify the waste(water) streams and to determine the availability and regional distribution of the most interesting streams. In doing so, the SME partners might use this information to further extend their business models.

Short title (native language):

Wiederverwertungspotential von Speiseabfällen und Abwässern in Bezug auf Phosphor

Short summary for practitioners (native language):

Eine erste grobe Analyse der Abwässer in Bezug auf das Wiederverwertungspotential von Phosphor zeigte, dass vor allem in den Abwässern aus der Speiseölproduktion, der Sojaverarbeitung, der Fleischverarbeitung und der Tierfutterproduktion ein relativ hoher Gehalt an Phosphor zu finden ist. Zudem ist im Vergleich zu kommunalem Abwasser auch der Kohlenstoffgehalt relativ hoch, so dass sich eine Wiederverwertung dieser Stoffströme lohnt.

Practice abstract 28

Short title (in English):

Nutrient and C recovery from food waste and wastewater

Short summary for practitioners (in English):

The activity creates new business potential of valorisation food waste via its processing into agricultural field. Acid whey, i.e. waste product from cottage cheese and cream cheese production is processed (mechanical pre-treatment, thickening and conservation) before it is placed into the soil to increase missing level of carbon there. Farmers could use acid whey to enrich their soil not only by carbon, but also by nutrients (nitrogen, phosphorus and potassium). It can create win-win scenario between dairy industry producers and farmers to create market with this commodity. Different dosage of acid whey is going to be tested during project duration (until 2022) to ensure necessary carbon level together with calculation nitrogen and phosphorus balances to give guidance and recommendations for practitioners about proper use of acid whey into the agricultural field. The guidance will contain proper dosage in the view of C, N, P and K, necessary acid whey pre-treatment, transport and storage issues together with some basic economic analysis about acid whey application.

Short title (native language):

Recyklace uhlíku a nutrientů z odpadní vody a potravinářského odpadu

Short summary for practitioners (native language):

Recyklace uhlíku z procesů zpracování kyselé syrovátky. Prováděná činnost vytváří nový obchodní potenciál valorizace potravinářského odpadu, který je zpracováván pro svojí aplikaci na pole. Kyselá syrovátka, což je odpadní produkt z výroby tvarohu, smetanového sýru a žervé je zpracovávána (mechanické předčištění, zahuštění a následná konzervace), předtím než je aplikována na půdu za účelem zvýšení hladiny uhlíku v ní. Zemědělci mohou využívat kyselou syrovátku nejen proto, aby dodali půdě chybějící uhlík, ale i nutrienty (dusík, fosfor a draslík). Může tak být vytvořen oboustranně výhodný scénář mezi mlékárnami a zemědělci a vytvořen trh s touto komoditou. V rámci projektu (do roku 2022) bude testována různá dávka kyselé syrovátky na půdu, která by zajistila nezbytnou hladinu organického uhlíku v půdě a zároveň budou zpracovávány dusíkové a fosforové bilance pro vytvoření návodů a doporučení pro koncové uživatele o vhodné aplikaci kyselé syrovátky na zemědělskou půdu. Doporučení budou obsahovat vhodnou dávku syrovátky z hlediska obsahu C, N, P a K, nezbytné zpracování syrovátky před jejím odvozem na pole, logistické a skladovací rady, spolu se základní ekonomickou analýzou o aplikaci kyselé syrovátky.

Practice abstract 29

Short title (in English):

Nitrogen recovery from food waste digestate

Short summary for practitioners (in English):

In Circular Agronomics, different organic waste and wastewater streams from food and agricultural industry are screened. The preparative screening revealed for nitrogen, that especially wastewaters from sugar manufacturing, animal feed production, dairies and meat processing contain relatively high nitrogen contents. However, the ratio of ammonium-nitrogen to total nitrogen in the raw wastewater is usually equal to 50% and less. For a higher and economically more favourable recovery rate in terms of nitrogen, the fraction of ammonium referring to the total nitrogen content needs to be increased. Therefore, anaerobic digestion of those wastewater streams can increase that fraction from 50% and less to a range between 60% and 80%. Due to that reason, Circular Agronomics will recover nitrogen from food waste digestates. Therefore, Circular Agronomics designs and constructs a pilot plant. This pilot plant will produce a "nitrogen depleted digestate" ready to serve as a soil conditioner. Furthermore, in the pilot plant, the nitrogen is recovered via ammonia degasification at vacuum conditions. In the subsequent gas scrubber, the degassed ammonia will react with sulfuric acid to ammonium sulfate solution. Ammonium sulfate solution is a typical mineral nitrogen fertilizer.

Short title (native language):

Stickstoffrückgewinnung aus Gärresten der Speiseabfallentsorung

Short summary for practitioners (native language):

In Circular Agronomics werden verschiedene organische Abfälle und Abwasserströme in Bezug auf ihr Wiederverwertungspotential betrachtet. Eine erste grobe Analyse verschiedener Stoffströme zeigte, dass vor allem in Abwässern aus der Zuckerherstellung, der Tierfutterherstellung, der Molkerei und der Fleischverarbeitung relativ hohe Stickstoffgehalte zu finden sind. Der Anteil des Ammonium-Stickstoffs bezogen auf den Gesamtstickstoff ist jedoch im rohen Abwasser relativ gering. Er liegt bei 50 % und weniger. Um eine höhere und wirtschaftlich güngstigere Rückgewinnungsrate bezogen auf den Stickstoff zu erreichen, muss der Ammoniumanteil erhöht werden. Dazu eignet sich eine anaerobe Behandlung, die den Ammoniumanteil von 50 % und weniger auf ein Niveau zwischen 60 % und 80 % erhöhen kann. Aus diesem Grund soll in Circular Agronomics insbesondere aus Gärresten der Speiseabfallentsorgung Stickstoff zurückgewonnen werden. Hierfür wird eine Pilotanlage konstruiert, die einen Stickstoff-abgereicherten Gärrest produziert, Dieser kann direkt als Bodenverbesserer eingesetzt werden. Zudem wird der Stickstoff über eine Ammoniakentgasung unter Vakuumbedingungen zurückgewonnen. In einem anschließenden Gaswäscher reagiert das Ammoniakgas mit Schwefelsäure zu Ammoniumsulfatlösung, was ein typischer mineralischer Stickstoffdünger ist.

Practice abstract 30

Short title (in English):

Phosphorus recovery from soybean waste/wastewater

Short summary for practitioners (in English):

Phosphorus is a life essential nutrient present in our daily food. So, the initial use of phosphorus is the application as fertilizer for food production. However, phosphorus is a mined resource with limited reserves, so to ensure food supply it will be needed to recover and reuse phosphorus. One the possibilities to do so is the recovery from used waters originated in feed/food processing containing phosphorus. The treatment of this used water in a traditional way results in phosphorus losses. The alternative approach in Circular Agronomics project is to recover the phosphorus by producing a well-defined crystalline product known as struvite. By implementing the correct process conditions, a selective process occurs resulting in the struvite product, which once produced can be readily separated from the used water. In addition, the struvite product has already fertilizer properties and contains next to the phosphorus also nitrogen and magnesium – two other essential elements needed for good plant growth. Starting with wastewater form food or feed processing also has the advantage of making a product that will be readily accredited the End-Off-Waste status. This is as important as the technology that the obtained product can be reintroduced in the circular economy under correct and certified conditions.

Short title (native language):

Fosfor terug winning uit afvalwater soja

Short summary for practitioners (native language):

Fosfor is een essentiële voedingsstof die aanwezig is in onze dagelijkse voeding. De belangrijkste toepssing van fosfor is dus de toepassing als meststof voor voedselproductie. Fosfor is echter een delfstof met beperkte reserves. Om de voedselvoorziening te garanderen, is het nodig om fosfor terug te winnen en opnieuw te hergebruiken. Een van de mogelijkheden om dit te doen is terugwinning uit proceswater afkomstig van voeder/voedselverwerking die veel fosfor bevatten. De behandeling van dit proceswater op een traditionele manier resulteert in het verlies van de fosfor. De alternatieve benadering, onderzocht in het Circular Agronomics-project, is het terugwinnen van de fosfor door een kristallijn product te produceren dat bekend staat als struviet. Door de juiste procesomstandigheden te implementeren, treedt een selectief proces op dat resulteert in het struviet product, dat eenmaal geproduceerd gemakkelijk kan worden afgescheiden uit het proceswater. Bovendien heeft het struviet product al bemestingseigenschappen en bevat het naast fosfor ook stikstof en magnesium - twee andere essentiële elementen die nodig zijn voor een goede plantengroei. Beginnen met afvalwater in de vorm van voedsel- of diervoederverwerking heeft ook het voordeel dat een product met de status End-Off-Waste gemakkelijk wordt geaccrediteerd. Dit is net zo belangrijk als de technologie dat het verkregen product onder correcte en gecertificeerde voorwaarden opnieuw in de circulaire economie kan worden geïntroduceerd.

Practice abstract 31

Short title (in English):

Electrospun-nanofibrous membrane for the treatment of whey

Short summary for practitioners (in English):

Electrospun nanofibrous membranes are proper alternative of recently used flat-sheet, tubular or ceramic membranes in the area of separation processes, e.g. filtration, mechanical pre-treatment, thickening, etc. Unique technology of electrospinning production of nanofibrous membranes produces membranes with holes up to 100 – 150 nanometers to ensure efficient separation or thickening of media. Electrospun nanofibrous membranes could serve in acid whey management in two different roles, either for pre-treatment before nanofiltration unit (replacement of centrifuge) for removal of fats and casein or for thickening of acid whey. Both hypotheses are going to be tested in lab-scale and pilot-scale during project duration (till 2022) to evaluate those applications. Project output will be feasibility study on electrospun-nanofibrous membrane application in the acid whey management before its further use (animal fodder, lyophilisation, soil conditioning). The study will contain all obtained results, considerations onto full-scale applications, return of investment analyses and market replication analysis.

Short title (native language):

Aplikace nanovlákenných membrán pro nakládání se syrovátkou

Short summary for practitioners (native language):

Nanovlákenné membrány jsou vhodnou a levnější alternativou deskových, tubulárních nebo keramických membrán v separačních procesech jako např. filtrace, mechanické předčištění, zahušťování, apod. Unikátní technologie elektrospinningu slouží k výrobě nanovlákenných membrán s velikostí pórů až 100 – 150 nanometrů pro zajištění účinné separace nebo zahuštění média. Nanovlákenné membrány mohou sloužit při nakládání s kyselou syrovátkou pro dva různé účel, buď jako předčištění před nanofiltrací (náhrada v současnosti používaných odstředivek) pro odstranění tuků a kaseinu anebo pro zahuštění kyselé syrovátky. Obě hypotézy se budou testovat v laboratorním a poloprovozním měřítku během trvání projektu (do roku 2022) pro kritické vyhodnocení těchto možných využití v praxi. Výstupem projektu bude studie proveditelnosti aplikace nanovlákenných membrán pro nakládání s kyselou syrovátkou před jejím dalším využitím (krmivo pro zvířata, lyofilizace, aplikace na půdu). Studie bude obsahovat všechny získané a naměřené výsledky, doporučení pro aplikaci v provozním měřítku, analýzu návratnosti investice a analýzu replikace technologií v praxi.

Practice abstract 32

Short title (in English):

Vacuum degasification of ammonia from food waste

Short summary for practitioners (in English):

Circular Agronomics aims to recover nitrogen from food waste in the form of ammonia via vacuum degasification. Therefore, especially protein-rich food waste is suitable due to its relatively high nitrogen content compared to other food waste streams. The higher the ammonium content is, the more nitrogen can be recovered. Therefore, prior to the degasification process, anaerobic digestion of those waste streams can increase the ammonium-nitrogen fraction referred to the total nitrogen content for example from 50% and less to a range between 60% and 80%.
In order to investigate and optimize the ammonia degasification process, Circular Agronomics designs and constructs a pilot plant. Circular Agronomics aims to degas and recover between 80% and 90% of the nitrogen that was originally present as ammonium in the manure. Thereby, the pressure conditions will be close to vacuum conditions between -700 and -900 mbar. The application of a pH between 8 and 10 as well as an elevated temperature of up to 70 °C will increase the ammonia content due to a shift of the equilibrium between ammonium and ammonia towards the side of ammonia. The process will be optimized within the course of the project by varying the pressure, the pH and the temperature conditions with regard to an energy efficient plant operation.

Short title (native language):

Stickstoffrückgewinnung aus Gärresten der Speiseabfallentsorung

Short summary for practitioners (native language):

Circular Agronomics zielt darauf ab, Stickstoff aus Speiseabfällen in Form von Ammoniak mittels einer Vakuumentgasung zurückzugewinnen. Insbesondere proteinreiche Speiseabfälle und Abwässer aus der Lebensmittelindustrie beinhalten einen relativ hohen Stickstoffgehalt im Vergleich zu anderen Speiseabfällen und Abwässern. Je höher der Ammoniumgehalt ist, desto mehr Stickstoff kann zurückgewonnen werden. Deshlab sollte vor der Vakuumentgasung der Ammoniumanteil durch eine anaerobe Behandlung erhöt werden. Dies kann z. B. zu einer Erhöhung des Ammoniumanteils bezogen auf den Gesamtstickstoffgehalt von ursprünglich 50 % und weniger auf ein Niveau zwischen 60 % und 80 % führen.

Um den Prozess der Ammoniakentgasung zu untersuchen und zu optimieren, wird in Circular Agronomics eine Pilotanlage geplant und gebaut. Cirular Agronomics zielt darauf ab, zwischen 80 % und 90 % des Stickstoffs, der ursprünglich als Ammonium vorlag, aus der Gülle zurückzugewinnen. Hierfür werden die Druckverhältnisse im Vakuumbereich zwischen -700 und -900 mbar eingestellt. Ein pH-Wert zwischen 8 und 10 sowie eine erhöhte Temperatur von bis zu 70 °C sorgen für eine Verschiebung des chemischen Gleichgewichts zwischen Ammonium und Ammoniak mit der Folge einer Erhöhung des Ammoniakanteils. Dieser Prozess wird im Projektverlauf optimiert, indem der Druck, der pH-Wert und die Temperaturbedingungen variiert werden mit dem Ziel, einen energieeffizienten Betrieb der Anlage zu erreichen.

Practice abstract 33

Short title (in English):

Phytase treatment for an enhanced phosphate release

Short summary for practitioners (in English):

To be able to recover the phosphorus as struvite it needs to be present as ortho-phosphate. The main phosphorus compound in soybean is however phytic acid, a cyclic P-containing compound. Phytic acid has a negative impact on food digestion by reducing protein degradation and uptake of micro-nutrients. Therefore, the addition of phythase enzymes to feed is a common practice and this open an opportunity to use phythases to convert the phytc acid in order to render struvite formation possible. The process under investigation is to condition the phosphorus present in the soybean wastewater in such a way it becomes available for struvite formation. This conditioning process uses the readily available enzymes (used as feed additive) to convert the bound phosphorus into free phosphate. Once the phosphate is present it can be transformed into the struvite compound. There are two types of struvite possible, the ammonia-struvite and potassium-struvite. These two different types of struvite can be produced at different stages of the used water treatment. The most important is NH4-struvite after the anaerobic stage. It should also be mentioned that one the specific features of soybean wastewater is that it contains more magnesium as phosphorus. This a rare case where thus not Mg but PO4-P is the limiting parameter. This does actually would make it possible to recover the struvite with no extra chemicals added but by sampling controlling pH by air sparging. The second possible outcome product is K-struvite. This can only be produced after the aerobic stage when all ammonia has been eliminated. The value of the K-struvite is higher compared to NH4-struvite since it is a rare non-soluble K-salt and K-reserves are also under stress.

Short title (native language):

Fytase behandeling voor doorgedreven fosfaat vrijstelling

Short summary for practitioners (native language):

Om fosfor als struviet terug te winnen, moet het aanwezig zijn als orthofosfaat. De belangrijkste fosforverbinding in soja is echter fytinezuur, een cyclische P-bevattende verbinding. Fytinezuur heeft een negatieve invloed op de spijsvertering door onder meer de afbraak van eiwitten en de opname van micronutriënten te verminderen. Daarom is de toevoeging van fytase-enzymen aan veevoeding een veel voorkomende praktijk en dit biedt de mogelijkheid om fytasen te gebruiken om het fytinezuur om te zetten om struviet vorming mogelijk te maken. Dit conditioneringsproces maakt gebruik van de direct beschikbare enzymen (gebruikt als toevoegingsmiddel) om de gebonden fosfor om te zetten in vrij fosfaat. Zodra het fosfaat aanwezig is, kan het worden omgezet in de struviet verbinding. Er zijn twee soorten struviet mogelijk, het ammonium-struviet en kalium-struviet. Deze twee verschillende soorten struviet kunnen in verschillende stadia van de gebruikte afvalwater behandeling worden geproduceerd. Het belangrijkste is NH4-struviet dat aan der orde is na de anaërobe zuivering. Het moet ook worden vermeld dat een van de specifieke kenmerken van soja-afvalwater is dat het meer magnesium als fosfor bevat. Dit is een zeldzaam geval waarbij dus niet Mg maar PO4-P de beperkende parameter is. Dit zou het mogelijk maken om het struviet terug te winnen zonder extra chemicaliën toe te voegen. Het tweede mogelijke product is K-struviet. Dit kan alleen worden geproduceerd na de aerobe fase wanneer alle ammonium is verwijderd. De waarde van de K-struviet is hoger in vergelijking met NH4-struviet omdat het een zeldzaam niet-oplosbaar K-zout is en K-reserves ook onder stress staan

Practice abstract 34

Short title (in English):

NH4-Struvite

Short summary for practitioners (in English):

One possible source of phosphorus in the agri-food chain is soybean wastewater. phosphorus present in soybean wastewater is a cyclic phytic acid. Phytic acid also has a negative impact on digestibility and uptake of some essential micro-elements such as iron and zinc. To counter act these negative effects the addition of phythase enzymes to feed is a well-known practice. The phythase enzyme degrades the phytic acid and liberates free ortho-phosphate. Ortho-phosphate is the phosphorus needed for struvite formation. In nature phythase enzyme production in anaerobic conditions is limited. Therefore, during anaerobic treatment of used water little or no phytic acid is degraded, as similar in the gut environment. Added phythase enzymes prior to anaerobic stage treatment of the used water the phytic acid is degraded and struvite formation as ammonium struvite becomes possible after the anaerobic used water treatment. The Circular Agronomics project develops the approach in detail to optimize the phythase assisted phytic acid conversion into orthophosphate to render struvite formation possible. At this stage of the used water treatment this will be as ammonium-struvite. A number of lab scale tests have been done to elaborate the boundary conditions which serve also as basic data to build a pilot unit to implement this approach at m3/h level. The value of NH4-struvite is in relation with the commodity value of the nutrients included, currently 1 ton of NH4-struvite sells between € 80 - € 120 as a dry granulated product. Important is that the product can be handled with existing equipment in the existing fertilizer plants. The real benefits are efficient control of phosphate with reduced chemical use (ic. Fe or Al-salts) and reduced sludge production.

Short title (native language):

NH4-Struviet

Short summary for practitioners (native language):

Het fosfor dat aanwezig is in het proceswater van sojaverwerking is cyclisch fytinezuur. Dit fytinezuur heeft een negatieve invloed op de verteerbaarheid en opname van enkele essentiële micro-elementen zoals ijzer en zink. Om deze negatieve effecten tegen te gaan, is de toevoeging van fytase-enzymen aan veevoeder een bekende en veelvuldig toegepaste praktijk. Het fythase-enzym breekt het fytinezuur af en maakt orthofosfaat vrij. Dit orthofosfaat is de fosforvorm die nodig is voor de vorming van struviet. In de natuur is de productie van fytase-enzymen onder anaerobe omstandigheden beperkt. Daarom wordt tijdens anaerobe behandeling van gebruikt water weinig of geen fytinezuur afgebroken, zoals vergelijkbaar in de anaerobe darm omgeving. Door fytase-enzymen toe te voegen voorafgaand aan de anaerobe behandeling van het gebruikte water wordt het fytinezuur afgebroken en struviet vorming onder de vorm van ammonium struviet wordt aldus mogelijk na de anaerobe waterbehandeling. Het Circular Agronomics-project ontwikkelt deze aanpak in detail om de fytase ondersteunde fytinezuurconversie in orthofosfaat te optimaliseren en zo struviet vorming mogelijk te maken. In deze fase van de waterbehandeling zal dit als ammonium-struviet zijn. De waarde van NH4-struviet staat in directe relatie met de grondstofwaarde van de nutriënten inhoud, momenteel verkoopt 1 ton NH4-struviet tussen € 80 en € 120 als een gedroogd gegranuleerd product. Belangrijk is dat het product kan worden gebruikt met bestaande apparatuur in de meststoffen industrie. De voordelen zijn efficiëntere controle van fosfaat met verminderd gebruik van chemicaliën en productie van slib vergeleken.

Practice abstract 35

Short title (in English):

K-Struvite

Short summary for practitioners (in English):

During aerobic treatment of the used water the phytic acid is degraded readily. However also the ammonium is removed. This opens the opportunity to produce the second type of struvite where the ammonium has been replaced by potassium. This type of struvite actually has a higher added value since it will not only recover phosphate but is one of the very few non water-soluble potassium compounds. Also, potassium is a limited raw resource which is stressed in terms of availability. In case the struvite formation is done as a tertiary phosphate removal after the aerobic stage treatment on the final effluent prior to discharge in surface water. Given the fact that the water at this stage is already relatively clear, a limited effort is needed. The addition of a magnesium salt will be required to induce the potassium-struvite formation. The benefit of using soybean wastewater is that it contains fairly high levels of potassium, making the phosphorus again the limiting parameter to be focussed upon. This approach does not require the use of phythase enzyme addition. The work done in the Circular Agronomics project is similar as to the ammonium-struvite: laboratory trials to determine boundary conditions a pilot unit to scale up. The pilot unit will have the flexibility to run in different operational modes. The obtained value of the K-struvite is in direct relation with the commodity value of the nutrients included, currently 1 ton of K-struvite sells between € 120 to € 150 as a dried granulated product. Important is that the product can be handled with existing equipment in the existing fertilizer plants. The real benefits are more efficient control of phosphate with reduced chemical use (ic. Fe or Al-salts) and reduced waste sludge production.

Short title (native language):

K-Struviet

Short summary for practitioners (native language):

Tijdens aerobe behandeling van het gebruikte water wordt het fytinezuur gemakkelijk afgebroken. Het ammonium wordt echter ook verwijderd. Dit opent de mogelijkheid om het tweede type struviet te produceren, waarbij het ammonium is vervangen door kalium. Dit type struviet heeft eigenlijk een hogere toegevoegde waarde omdat het niet alleen fosfaat terugwint, maar één van de weinige niet water oplosbare kaliumverbindingen is. Kalium is ook grondstof met beperkte beschikbaarheid. In dit geval wordt de struviet vorming uitgevoerd als een tertiaire fosfaatverwijdering na de aërobe behandeling op het uiteindelijke effluent voorafgaand aan lozing in oppervlaktewater. Gezien het feit dat het water in dit stadium al relatief zuiver is, is er een beperkte behandeling noodzakelijk. De toevoeging van een magnesiumzout zal nodig zijn om de vorming van kalium-struviet te induceren. Het voordeel van het gebruik van soja-afvalwater is dat het vrij hoge kaliumgehalte bevat, waardoor fosfor opnieuw de beperkende parameter is waarop kan worden gefocust. De pilooteenheid zal de flexibiliteit hebben om in verschillende operationele modi te werken. De waarde van K-struviet staat in directe relatie met de grondstofwaarde van de nutriënten inhoud, momenteel verkoopt 1 ton K-struviet tussen € 120 en € 150 als een gedroogd gegranuleerd product. Belangrijk is dat het product kan worden gebruikt met bestaande apparatuur in de meststoffen industrie. De echte voordelen zijn een efficiëntere controle van fosfaat met verminderd gebruik van chemicaliën (ic. Fe of Al-zouten) en verminderde productie van slib vergeleken.

Practice abstract 36

Short title (in English):

Nutrient (N, P and C) flows into & from the EU-28 (import/export)

Short summary for practitioners (in English):

Worldwide nutrient flows are not only related to political dependencies, but also to resource efficiency and closing nutrient cycles. Mainly the product value chains and international trade of fertilising products, feed and food products are responsible for significant local nutrient imbalances.
The analysis based on FAO data shows that imported proteins related to feed products for European animal husbandry mainly from South America, but also from North America and Ukraine cause a significant reallocation of the key nutrients carbon (C), nitrogen (N) and phosphorus (P). From 2013 to 2017, about 51 % with more than 10 Mt proteins were imported mainly as soy and soy cake from South America dominated by Argentine, Brazil and Paraguay. The high protein content of soy products contributes almost 90 % to the nutrients imported to the EU: approx. 5 600 kt C, 1 860 kt N and 150 kt P. The production of animal products and derivatives lead to atmospheric and terrestrial losses of nutrients. The overall nutrient efficiency is low which results in additional costs for producers.
Wheat contributes the main share of exported proteins from the EU to Africa (69 % of the 3,1 Mt proteins), followed by barley (6%), dried skimmed milk and chicken meat. The key destinations in Africa are Algeria, Egypt and Morocco where the imports from the EU causes disadvantages for locally produced foods and damages the environment through, among others, higher transport and storage emissions.

Short title (native language):

Nährstoffflüsse (N, P und C) in & aus der EU-28 (Import/Export)

Short summary for practitioners (native language):

Weltweite Nährstoffflüsse beeinflussen politische Abhängigkeiten, Ressourceneffizienz und Schließung von Nährstoffkreisläufen. Vor allem die Wertschöpfungsketten und der internationale Handel von Düngemitteln, Futter- und Lebensmitteln sind für lokale Nährstoffungleichgewichte verantwortlich.
Die auf FAO-Daten basierende Analyse zeigt, dass Eiweißimporte durch Futtermittel für die europäische Tierhaltung vor allem aus Südamerika, Nordamerika und der Ukraine eine signifikante Reallokation der Schlüsselnährstoffe Kohlenstoff (C), Stickstoff (N) und Phosphor (P) verursachen. Von 2013 bis 2017 wurden ca. 51 % mit mehr als 10 Mt Eiweiß vorwiegend als Soja und Sojakuchen aus Südamerika, dominiert aus Argentinien, Brasilien und Paraguay importiert. Der hohe Proteingehalt von Sojaprodukten trägt fast 90 % zu den EU-importierten Nährstoffen bei: ca. 5.600 kt C, 1.860 kt N und 150 kt P. Die Herstellung tierischer Produkte und Derivate führt zu atmosphärischen und terrestrischen Nährstoffverlusten. Die Nährstoffeffizienz ist insgesamt gering, was zu hohen Kosten für die Produzenten führt.
Weizen trägt den Hauptanteil der exportierten Proteine aus der EU nach Afrika bei (64 % der Proteine), gefolgt von Gerste (5 %), Magermilchpulver und Hühnerfleisch. Die wichtigsten Zielländer in Afrika sind Algerien, Ägypten und Marokko, wo die EU-Produkte Nachteile für die lokalen Wertschöpfungsketten verursachen und die Umwelt unter anderem durch höhere Transport- und Lagerungsemissionen schädigen.

Practice abstract 37

Short title (in English):

Analysis of legislations related to Circular Economy in Agriculture

Short summary for practitioners (in English):

The three key policy areas defined in Circular Agronomics are agriculture, waste and emissions to the environment such as CO2, methane, nitrous oxide or ammonia. Along the value chains various barriers and gaps were identified for the practical solutions to improve nutrient cycling in European agro-ecosystems.
One focus was on the EU Fertilising Product Regulation (2019/1009/EC) which boosts the use of organic and bio-based fertilisers e.g. from municipal biowaste. It sets EU-wide quality, safety and environmental criteria for EU fertilisers. However, producers can choose between European and national certification. The regulation still excludes industrial or sewage sludge as component material for fertilisers and notified bodies are not bound by any mandatory timeframe for giving their assessment to requesting manufacturers. Hence, the procedure is risky for producers and will depend on repeatability and product nature.
The legislative analysis contributes to the potential market uptake of innovations and European initiatives. A novel approach in policies for nutrient life-cycling and bio-based products is mandatory like quality (not source) related definitions and declarations. Waste should be managed as secondary raw materials that are financially supported wherever possible. In parallel, the enforcement of existing European legislation and the development of effective joined up policy are facilitated - further steps towards integrating agriculture in circular economy.

Short title (native language):

Analyse der Gesetzgebung zur Kreislaufwirtschaft in der Landwirtschaft

Short summary for practitioners (native language):

Die drei Haupt-Politikbereiche in Circular Agronomics sind Landwirtschaft, Abfall und Umweltemissionen wie CO2, Methan, Lachgas oder Ammoniak. Entlang der Wertschöpfungsketten wurden Barrieren und Lücken für praktische Lösungen zur Verbesserung des Nährstoffkreislaufs in EU-Agrarökosystemen identifiziert.
Ein Schwerpunkt lag auf der EU-Düngemittelverordnung (2019/1009/EC), die den Einsatz von organischen/biobasierten Düngemitteln z.B. aus kommunalen Bioabfällen fördert. Sie legt EU- Qualitäts-, Sicherheits- und Umweltkriterien für EU-Düngemittel fest. Die Hersteller können jedoch zwischen europäischer und nationaler Zertifizierung wählen. Die Verordnung schließt nach wie vor Industrie- oder Klärschlamm als Düngemittel-Bestandteil aus und Genehmigungsstellen sind an keine verbindlichen Zeiten für ihrer Bewertung gebunden. Dieses Verfahren ist für Hersteller risikoreich und wird von Wiederholbarkeit und Art des Produkts abhängen.
Die Gesetzgebungsanalyse trägt zur potenziellen Marktakzeptanz von Innovationen und EU-Initiativen bei. Ein neuer Politikansatz für Nährstoffkreisläufe und biobasierte Produkte ist notwendig wie qualitäts- (nicht herkunfts-) bezogene Definitionen und Deklarationen. Abfälle sollten als Sekundärrohstoffe behandelt werden, deren Einsatz finanziell unterstützt wird. Parallel werden die bestehenden EU-Gesetze durchgesetzt und die Entwicklung einer effektiv vernetzten Politik erleichtert - Schritte zur Integration der Landwirtschaft in die Kreislaufwirtschaft.

Practice abstract 38

Short title (in English):

CO2-Stripping prior to vacuum degasification of biogas digestate reduces the need of alkaline pre-treatment

Short summary for practitioners (in English):

To remove ammonium (NH4+) from biogas digestate, it has to be converted to its gaseous form (NH3). Both forms are present in the liquid phase with their distribution being dependent on the pH-value. Naturally, digestate from biogas plants has a pH-value around 7.5. When pH is around 9.2, equal amounts of ammonium and ammonia can be found. To achieve this, caustic soda is added to the digestate. The amount needed varies from substrate to substrate and has been found to be around 4.5 – 7.5 grams per litre of substrate. This value is inflated by carbon dioxide species, which act as a buffer in that pH-range. When caustic soda is added, carbon dioxide is fixed in the liquid phase as hydrogen carbonate and additional caustic soda is needed to overcome the hydrogen carbonate – carbonate buffer capacity.
In our batch experiments we found air stripping of CO2 prior to vacuum degasification an effective way to reduce the need of alkaline pre-treatment, because it allows carbon dioxide to escape from the liquid phase and consequently lowers the buffer capacity. Additionally, it leads to a natural pH-increase to approximately 8.6. The amount of NaOH needed was reduced to 1.5 – 3 g/L. The stripping was conducted with 75 L air per litre of substrate at a pressure of 800 mbar at 70 °C. Additionally, the concentration of ammonia already sees some reduction in this phase.

Short title (native language):

CO2-Strippung vor der Vakuumentgasung von Gärresten reduziert den Laugenbedarf

Short summary for practitioners (native language):

Um Ammonium (NH4+) aus Gärresten zu entfernen, muss es in seine Gasform (NH3) überführt werden. Beide Formen liegen in der Flüssigphase parallel vor, wobei die Verteilung abhängig vom pH-Wert ist. Roher Gärrest hat einen natürlichen pH-Wert von ungefähr 7,5. Wenn dieser bei 9,2 liegt, liegen beide Spezies zu gleichen Konzentrationen vor. Um das zu erreichen, wird Natronlauge zum Gärrest zu dosiert. Die benötigte Menge ist abhängig vom jeweiligen Substrat und war in unseren Versuchen ca. 4,5 – 7,5 g NaOH pro Liter Gärrest. Dieser Wert wird durch gelöste Kohlenstoffdioxidspezies erhöht, der in diesem pH-Bereich als Puffer fungiert. Wenn Lauge hinzugegeben wird, wird Kohlenstoffdioxid als Hydrogencarbonat in der Flüssigphase fixiert und zusätzliche Lauge wird benötigt, um den Hydrogencarbonat – Carbonat – Puffer zu überwinden.
In unseren Batch-Experimenten wurde erkenntlich, dass CO2-Strippung vor der Vakuumentgasung ein effektiver Weg ist, den Laugenbedarf zu reduzieren. Es erlaubt dem Kohlenstoffdioxid als Gas aus der Flüssigphase auszutreten und verringert so die Pufferkapazität. Zusätzlich führt es zu einem natürlichen pH-Anstieg auf ca. 8,6. Die benötigte Menge NaOH konnte so auf 1,5 – 3 g/L reduziert werden. Im Strippprozess wurden 75 L Luft pro L Gärrest bei 800 mbar Absolutdruck und 70 °C Temperatur eingesetzt. Zusätzlich dafür konnte bereits in diesem Prozessschritt eine Verringerung des NH4-N-Gehaltes festgestellt werden.

Practice abstract 39

Short title (in English):

Vacuum degasification of biogas digestate and its pre-treatment affect more parameters than just the nitrogen content

Short summary for practitioners (in English):

The pre-treatment of digestate before vacuum degasification includes the addition of alkaline substances and heating of the substrate, both with the objective of increasing the ammonia removal efficiency. In our trials we found those actions to be impacting more parameters than just the nitrogen removal.
Adding bases like sodium hydroxide raises the dry residue percentage and increases the alkalinity and salinity. Consequently, it’s adding to the electrical conductivity of the substrate while simultaneously preventing CO2 from being removed due to the increased pH. If no caustic soda is added, the process is able to eliminate most of the carbon dioxide, lowering the acid capacity and electrical conductivity. Some chemical compounds like calcium and magnesium form insoluble salts with phosphates when the pH value rises and are moved from the liquid to the solid phase this way. Volatile fatty acids (VFA) tend to increase in the process. This is due to the thermo-alkaline hydrolysis, where long hydrocarbon chains are broken down and cell boundaries of intact microorganisms are destroyed. In combination with the removal of ammonium, which is an inhibitor of anaerobic digestion depending on concentration, this could mean a valuable gain in digestion efficiency for biogas plants if used as a side stream application.

Short title (native language):

Vakuumentgasung landwirtschaftlicher Gärreste beeinflusst auch andere Parameter als den Stickstoffgehalt

Short summary for practitioners (native language):

Die Vorbehandlung des Gärrests vor der Vakuumentgasung beinhaltet die Zugabe von alkalinen Substanzen und die Erhitzung des Substrats. Beides hat das Ziel, die Ammoniakeliminationseffizienz zu erhöhen. In den durchgeführten Versuchen konnte beobachtet werden, dass durch den Prozess mehr Parameter als nur der Stickstoffgehalt beeinflusst werden.
Basen wie Natriumhydroxid erhöhen den Trockenrückstand und die Alkalinität sowie Salinität des Gärrests. Folglich führt es auch zu einer erhöhten Leitfähigkeit und fixiert außerdem durch die Erhöhung des pH-Wertes CO2 als Carbonat, wodurch es nicht mehr ausgasen kann. Sollte keine Lauge hinzugegeben werden, ist der Prozess in der Lage, den Großteil des gelösten CO2 zu eliminieren. Dadurch sinken die Säurekapazität und elektrische Leitfähigkeit. Einige Elemente wie Calcium und Magnesium wechseln mit Phosphaten von der gelösten Form zu festen, unlöslichen Salzen und sind somit nicht mehr in der Flüssigphase detektierbar. Volatile Fettsäuren haben eine Tendenz, über die Prozessdauer anzusteigen. Das liegt an der thermisch-alkalischen Hydrolyse des Substrats, wobei langkettige Kohlenwasserstoffe herabgebrochen und Zellbegrenzungen intakter Mikroorganismen zerstört werden. In Kombination mit der Entfernung von Ammonium, welches konzentrationsabhängig die anaerobe Faulung hemmen kann, könnte dies eine Vergrößerung der Faulungseffizienz in Biogasanlagen bedeuten, wenn der Prozess als Seitenstrom implementiert ist.

Practice abstract 40

Short title (in English):

Best available techniques for livestock emission reduction

Short summary for practitioners (in English):

According to Directive 2010/75 / EU on industrial emissions (DIE), the best available techniques (BAT) are the most environmentally friendly way known to carry out an activity, taking into account that the cost of such BAT are within of reasonable limits. Current legislation establishes, in general, the obligation of the owners of the affected facilities to apply BAT. In relation to intensive pig production, MTD30 practices are intended to reduce emissions inside housing systems; MTD16, 17 and 18 aim to reduce or avoid atmospheric emissions during slurry storage; MTD19 avoid emissions during on-farm processing of manure; and MTD20, 21 and 22 avoid emissions during agricultural application. In the Circular Agronomics project, the MTD19-c is experimentally validated by applying an on-farm drying process. For this, an evaporation at atmospheric pressure, using solar energy, is applied to the clarified fraction of anaerobic digested slurry in the farm. To avoid NH3-gas emissions during solar drying, the initial pH is adjusted (pH <6) and a biofiltration of the outcoming air is carried out. The product of this process is a material with very low humidity (≤15% weight), whose agronomic value is validated by winter cereal cultivation.

Short title (native language):

Mejores técnicas disponibles para la reducción de emisiones

Short summary for practitioners (native language):

Según la Directiva 2010/75/EU sobre las emisiones industriales (DEI), las mejores técnicas disponibles (MTD) son la manera ambientalmente más respetuosa que se conoce para llevar a cabo una actividad, teniendo en cuenta que el coste de dicha MTD estén dentro de unos límites razonables. La legislación vigente establece, con carácter general, la obligación de los titulares de las instalaciones afectadas a aplicar las MTD. En relación a la producción porcina intensiva, las prácticas MTD30 pretenden reducir la emisión dentro de las naves, las MTD16, 17 y 18 pretenden reducir o evitar emisiones atmósfericas durante el almacenamiento de purines, mientras que las MTD19 evitan emisiones durante el tratamiento (en granja) de los purines y las MTD20, 21 y 22, durante la aplicación agrícola. En el proyecto Circular Agronomics, se valida experimentalmente la MTD19-c mediante la aplicación de un proceso de secado en granja. Para ello, se aplica una evaporación a presión atmosférica, usando energía solar, a la fracción clarificada de purín digerido anaeróbicamente en granja. Para evitar las emisiones de NH3-gas durante el secado solar, se ajusta el pH inicial (pH <6) y se realiza una biofiltración del aire de salida del secadero. El producto de este proceso es un material con muy poca humedad (≤15% peso), cuyo valor agronómico se valida mediante cultivo de cereales de invierno.

Practice abstract 41

Short title (in English):

Using bacteriophages to reduce ammonia emissions in ruminant production

Short summary for practitioners (in English):

High-ammonia producing bacteria (HAB) present in the rumen of ruminants are responsible of an important part of ammonia emissions in the livestock sector. Ammonia produced by HAB is absorbed in the rumen and it is finally excreted as urea in the urine. One potential approach to decrease nitrogen emissions in ruminants could be the reduction of HAB in the rumen. Thus, bacteriophages against HAB appears as an interesting approach to reach this objective. Bacteriophages, also known as phages, are viruses that infect and destroy bacteria. They are composed by a capsid that contains DNA or RNA. One of the most interesting properties is their host specificity, which means that using a specific bacteriophage is possible to specifically destroy only one specific type of bacteria (host bacteria). For that reason, phages have been widely studied for therapy purposes as antibiotic alternative agents against pathogenic bacteria, being promising strategy. Besides, phages are also used as food additives to prevent bacterial contamination. However, there are other fields in which the use of phages has not been explored so far. Thus, Circular Agronomics project aims to determine if bacteriophages against HAB could be a feasible approach to reduce the amount of HAB in dairy cows rumen without affecting rumen microbiota. For that, HAB and bacteriophages against HAB are being isolated and identified from the rumen of cows at different production stages (growing, lactating, dry-off). After that, the application of bacteriophages to reduce/eliminate the ammonia production will be used in an in vitro assay.

Short title (native language):

Utilización de bacteriófagos (B) para reducir emisiones de amoníaco en producción de rumiantes

Short summary for practitioners (native language):

Las bacterias productoras de amonio presentes en el rumen son responsables de una parte importante de las emisiones de amonio en el sector ganadero. El amonio que producen estas bacterias es absorbido por el rumen y es finalmente excretado en forma de urea en la orina. Una potencial aproximación para reducir las emisiones de N en los rumiantes podría ser la reducción de las bacterias productoras de amonio presentes en el rumen. En este contexto, el uso de B contra estas bacterias se plantea como una aproximación interesante para alcanzar este objetivo. Los B, son virus que infectan y destruyen bacterias. Están formados por una cápside que contiene DNA o RNA. Tienen una elevada especificidad frente a su huésped, es decir, usando B es posible destruir de forma específica un solo tipo de bacteria. Por esta razón, los B han sido ampliamente usados con fines terapéuticos como una alternativa a los antibióticos frente a bacterias patogénicas. Los B son también usados como aditivos alimentarios para prevenir la contaminación bacteriana. No obstante, hay otros campos en los que su aplicación no se ha explorado hasta en momento. Por ello, el Proyecto Circular Agronomics tiene por objetivo determinar si los B que infectan bacterias productoras de amonio podrían reducir el número de estas bacterias en el rumen de vacas lecheras sin afectar la microbiota ruminal. Para ello, las bacterias productoras de amonio y los B contra éstas están siendo aislados e identificados del rumen de vacas en distintos estadios de producción (crecimiento, lactación y secado). Una vez finalizado este proceso, se testará la efectividad de la aplicación de estos bacteriófagos para reducir/eliminar la producción de amonio mediante un ensayo in vitro.

Practice abstract 42

Short title (in English):

Advantages of compost-bedded pack systems in cattle farms

Short summary for practitioners (in English):

Housing animal conditions are critical for animal health, welfare, and hygiene, and consequently their feed efficiency. In dairy cows, bedding is especially important to keep legs and udders in good health. Traditionally, daily bedded loose barns or cubicle barns were the most common systems, with controversial results in hygiene and lameness problems, in respectively management systems. Recently, a well-manage compost-bedded pack systems seems to accomplish both premise: hygiene and healthy legs. This consists in a loose housing system that requires periodic bedding addition and daily tilling the top 20-30 cm of the pack with a roto-tiller or cultivator. The purpose of this system is to oxygen the bedding to foster microbial activity, to heat and dry the bedding to achieve a dry surface area for lying. Key parameters to succeed managing compost-bedded pack systems are: 1) keep bedding moisture between 40-60% for cleanness, promoting barn ventilation and adding materials when moisture increases; 2) achieve 40-60ºC for drying and eliminate pathogens in the bedding; 3) achieve at least 50 cm height to promote composting; 4) keep a ratio C:N in the bedding of 25:1 or 30:1 to enhance composting; 5) keep pH < 8 to avoid ammonia volatilization; 6) keep animals at 9-15 dairy cows/m2. As all management systems, having in mind these conditions will make the difference to succeed or not in managing a compost-bedded barn.

Short title (native language):

Ventajas de la cama compost en granjas de bovino

Short summary for practitioners (native language):

Las condiciones de alojamiento de los animales son críticas para su salud, bienestar e higiene, y en consecuencia para su eficiencia alimentaria. Para las vacas lecheras, el tipo de encamado y de suelos es crítico para la salud de sus ubres y piernas. Tradicionalmente, los animales se alojan en sistemas de cama caliente, donde se añade diariamente cama (paja, serrín, arena...) o en cubículos, siendo los primeros críticos con la higiene y los segundos con la salud podal. Recientemente, la cama compost se presenta como un sistema que permite mantener la higiene de los animales y una buena salud podal. Este sistema consiste en añadir cama periódicamente en el área de descanso, y pasar un cultivador a diario en la superficie de la cama (20-30 cm) para airear la cama y favorecer la actividad microbiana que hará que aumente de temperatura y se seque, con el objetivo de conseguir un área de descanso seca. Los puntos clave para un buen manejo de la cama compost son: 1) mantener una humedad entre 40-60% de la cama para la higiene de los animales, promoviendo una buena ventilación de la nave y añadiendo material cuando incremente la humedad de la cama; 2) conseguir temperaturas de 40-60ºC para secar la cama y eliminar patógenos de la cama; 3) conseguir una altura de 50 cm para promover el compostaje, 4) mantener una ratio de C:N de 25:1 o 30:1 para maximizar el proceso de compostaje; 5) mantener el pH por debajo de 8 para evitar la volatilización de amoníaco; 6) mantener una densidad de 9.15 animales/ m2. Como cualquier otro sistema de manejo, tener en mente estas condiciones hará la diferencia entre tener éxito o fracasar en el manejo del sistema de cama-compost.

Practice abstract 43

Short title (in English):

Obtaining biofertilizers from digestates by solar drying and stripping absorption processes

Short summary for practitioners (in English):

The solar drying process is being improved and optimized within the Circular Agronomics project. The basic system consists of 3 parts: Firstly, manure is acidified to avoid ammonia emissions. Secondly, the drying process evaporates water, and finally, the remaining emissions are treated by biofiltration. The innovation carried out during the project includes a mechanical and rotatory stirrer that moves throughout the dryer breaking the upper dried crust that naturally appears in manure storages. This device allows to improve the solar drying efficiency by increasing the contact surface between manure (or digestate) and air. However, more emissions are produced when breaking the crust, which are finally minimized by using the biofilter. In the frame of the project, we are drying digestate from pig manure with and without previous centrifugation, i.e, the raw digestate after anaerobic digestion (D) and its solid fraction (SF). Besides, a stripping and absorption unit has been installed to produce ammonium sulfate from the remaining liquid fraction (LF). Two solar dryers have been built in order to dry, not only the D and the SF, but also the mix of them with the streams coming from the stripping/absorption unit. The final objective es to produce high quality dried fertilizers with low humidity content that meet the Regulation (EU) 2019/1009 on fertilizers products.

Short title (native language):

Obtención de biofertilizantes a partir de digestatos mediante secado solar y procesos de stripping/absorción

Short summary for practitioners (native language):

El proceso de secado solar se está mejorando y optimizando dentro del proyecto Circular Agronomics. El sistema básico consta de 3 partes: En primer lugar, se acidifica el estiércol para evitar emisiones de amoniaco. En segundo lugar, el proceso de secado evapora el agua y, finalmente, las emisiones restantes se tratan mediante biofiltración. La innovación llevada a cabo durante el proyecto incluye un agitador mecánico y rotatorio que se mueve por todo el secadero rompiendo la costra superior seca que aparece de forma natural en los depósitos de estiércol. Este dispositivo permite mejorar la eficiencia del secado solar aumentando la superficie de contacto entre el estiércol (o digestato) y el aire. Sin embargo, se producen más emisiones al romper la costra, que finalmente se minimizan mediante el uso del biofiltro. En el marco del proyecto, estamos secando el digestato de estiércol de cerdo con y sin centrifugación previa, es decir, el digestato después de la digestión anaeróbica (D) y su fracción sólida (SF). Además, se ha instalado una unidad de stripping y absorción para producir sulfato de amonio a partir de la fracción líquida restante (LF). Se han construido dos secaderos solares para secar, no solo el D y el SF, sino también la mezcla de los mismos con los chorros provenientes de la unidad de stripping / absorción. El objetivo final es producir fertilizantes de alta calidad con bajo contenido de humedad que cumplan con el Reglamento (UE) 2019/1009 sobre productos fertilizantes.

Practice abstract 44

Short title (in English):

The agricultural performance of NH4-struvite

Short summary for practitioners (in English):

NH4-struvite is Ammonium-Magnesium-Phosphate. It is a mineral fertilizer derived from wastewater, slurry or digestate treatment. In field trials and in several pot trials the efficiency of struvite as mineral fertilizer was analysed.
The main results are:
-all three nutrients (N, Mg, P) are as plant available as compared to conventional mineral fertilizers.
-Struvite is a slow-release fertilizer. It is not water soluble at pH 7 but readily dissolves al lower ph (5-6). Plant roots grow to the fertilizer and dissolve it by plant induced acidification of the root environment.
- Struvite fertilization reduces Nitrate leaching and nitrous oxide emissions (a strong greenhouse gas). Because. Around 10% of the N demand of plants are covered by the N in the struvite. The struvite-N is not nitrified, as long it is part of the struvite mineral. When struvite is dissolved by root acidification, the released struvite NH4 is readily transported into the plant and there is no nitrification in the soil.
Practical recommendations:
-Struvite can replace equally water-soluble Phosphorous fertilizers.
- Struvite is a sustainable mineral fertiliser because it reduces nitrate leaching and greenhouse gas emissions by 10% each.

Short title (native language):

Die landwirtschaftliche Leistungsfähigkeit von NH4-Struvit

Short summary for practitioners (native language):

NH4-Struvit ist Ammonium-Magnesium-Phosphat. Es ist ein Mineral, das bei der Behandlung von Abwasser, Gülle oder Gärrest entsteht. In mehrjährigen Feldstudien und Topf-Experimenten wurde die Effizienz von Struvit als Mineraldünger untersucht.
Die wesentlichen Ergebnisse sind:
-Alle drei Nährstoffe (N, Mg, P) sind genauso verfügbar wie aus konventionellen Mineraldüngern.
-Struvit ist ein Langzeitdünger. Es ist bei pH 7 nicht wasserlöslich, sondern löst sich erst bei pH 5-6 gut auf. Pflanzenwurzeln wachsen in Richtung Düngemittel und lösen das Struvit durch die pflanzeninduzierte pH-Absenkung in der Wurzelzone auf.
-Struvit-Düngung reduziert die Nitratauswaschung ins Grundwasser und die Lachgasemissionen (ein starkes Treibhausgas). Etwa 10% des Stickstoffs, die Pflanzen für ihr Wachstum benötigen, stammt bei Struvitdüngung aus dem Struvit. Struvit-N wird im Boden nicht nitrifiziert, solange es Teil des Struvit-Minerals ist. Wenn Struvit durch die wurzelinduzierte pH-Absenkung aufgelöst wird, gelangt das freiwerdende NH4-N direkt in die Pflanze und kann im Boden nicht nitrifiziert werden.
Praxisempfehlung:
- Struvit kann wasserlösliche konventionelle Phosphor-Dünger ebenbürtig ersetzen.
- Struvit ist ein nachhaltiges Düngemittel, denn es reduziert die Nitratauswaschung und die Lachgasemissionen um jeweils etwa 10%.

Practice abstract 45

Short title (in English):

The recovery of P in form of Hazenite (KNa-struvite)

Short summary for practitioners (in English):

Struvite commonly refers to MgNH4PO4-which is a non-water soluble but excellent fertilizer. Struvite is produced in some wastewater/slurry/digestate treatment plants. It removes phosphate from the liquid. Some industrial wastewater streams do not contain ammonium (NH4) that is necessary for NH4-Struvite precipitation. In that case, potassium (K) or even sodium (Na) may replace ammonium. In a wastewater with a Na/K molar ratio of >1, the struvite specification Hazenite can be precipitated (KNaMg2(PO4)2*13H2O).
Main findings:
- Hazenite is only precipitated in the absence of ammonium.
- Hazenite seems to form smaller cristals as compared to NH4-struvite.
- In pot experiments the nutrients Mg, K, Na, P have the same fetrtilizer efficiency as compared to conventional mineral fetrtilizers
- Because of the lack of N in Hazenite, it could be a very interesting fertilizer for organic farming. Organic farming tries to fertilize nitrogen via legumes and not via mineral fertilizers.
Pracitcal recommendations:
- Industrial wastewater plants with high salt concentrations may precipitate P from waste water even in absence of ammonium.
- The precipitated Hazenite is not soluble in water at pH 7. It is a fertilizer equal to water soluble P-fertilizers
- Hazenite could be an excellent P-fertilizer for organic farming as it does not contain nitrogen.

Short title (native language):

Die Gewinnung von P in Form von Hazenit (KNa-Struvit)

Short summary for practitioners (native language):

Als Struvit wird im allgemeinen die Struvitform MgNH4PO4 bezeichnet. Struvit werden in der Abwasser/Gülle/Gärrestbehandlung produziert. Damit wird Phosphat aus dem Wasser entfernt. Einige Abwasserströme weisen kein Ammonium auf, welches für die ammonium-Struvit-Fällung notwendig ist. In diesem Fall kann Kalium (K) oder Natrium (Na) das Ammonium ersetzen. In Abwässern mit einem molaren Na/k-Verhältnis >1 kann die Struvitform Hazenit ((KNaMg2(PO4)2*13H2O) ausgefällt werden.
-Hazenit kann nur in Abwässern ohne Ammonium ausgefällt werden.
- Hazenit scheint im Gegensatz zu Ammonium-Struvit als kleinere Kristalle auszufällen.
- In Gefäßversuchen zeigten die Nährstoffe K, Na, Mg, P im Hazenit die gleiche Nährstoffeffizienz wie die Nährstoffe aus Mineraldüngern.
- Da Hazenit kein Stickstoff enthält, ist das Material ein interessanter P-Dünger für die Bio-Landwirtschaft, denn in den ökologisch bewirtschafteten Böden fehlt einerseits Phosphor. Andererseits soll die Stickstoffdüngung durch N-Fixierung über Leguminosen erfolgen.
Praxisempfehlung:
- Industrieabwässer mit hohen Salzfrachten können Phosphat als Struvit ausfällen, auch wenn kein Ammonium im Abwasser enthalten ist.
- Das ausgefällte Hazenit ist bei pH 7 nicht wasserlöslich. Die Nährstoffeffizienz ist ebenbürtig mit konventionelle mineralischen Düngern.
- Hazenit könnte ein interessanter P-Dünger für den Ökolandbau sein, da Hazenit keinen Stickstoff enthält.

Practice abstract 46

Short title (in English):

Factors affecting farmers’ adoption decision of innovative circular farming practices and solutions in EU.

Short summary for practitioners (in English):

The agricultural and livestock sectors are facing several challenges to achieve the current EU environmental objectives. Reducing GHG emissions and ensuring that a great share of N, P and K coming from renewable sources are one of the major policy goals. In this context, farmers are continuously looking to adopting innovative technologies and solutions that may ensure sustainable food production systems. The adoption process of innovations at the farm level based on the circular economy concept may improve resource efficiency, allow the reuse and recovery of nutrients and reduce the negative effect of emissions on soils, water and air. The farmers’ decision to accept and adopt the innovative solutions depends mainly on the initial investments and return, benefits and costs, farm structure, farmers’ socio-economic characteristics, farmers’ attitudes, opinions and behaviour and, external markets conditions among other determinant reasons. This study aims at identifying the determinant factors and barriers that affect farmers’ adoption of several Circular Agronomy Solutions using a semi-structured questionnaire on an exploratory sample of farmers in 5 EU countries. Preliminary results showed that the level of acceptance of the proposed innovations is highly related to farmers’ economic motivations and objectives. The cost of the investment, the return rate, the institutional support, risk and environmental attitude play a relevant role in the adoption decision. Results of the adoption preferences may assist policy-makers in designing more specific and efficient measures and tools that may help farmers to face the current environmental challenges and social needs.

Short title (native language):

Factores determinantes de la decisión de los agricultores de adoptar prácticas y soluciones innovadoras de agricultura circular en la UE.

Short summary for practitioners (native language):

El sistema agrario actual se enfrenta a varios retos para alcanzar los actuales objetivos medioambientales de la UE. Reducir las emisiones de GEI y garantizar que una gran parte del N, P y K provenga de fuentes renovables es uno de los principales objetivos políticos. Por ello, los agricultores buscan la adopción de soluciones que puedan garantizar sistemas de producción sostenible de alimentos. La adopción de innovaciones circulares puede mejorar la eficiencia de los recursos, permitir la reutilización y recuperación de nutrientes y reducir el efecto negativo de las emisiones en el suelo, el agua y el aire. La decisión de los agricultores de aceptar y adoptar las dichas soluciones depende principalmente de las inversiones iniciales y su rendimiento, los beneficios y costes, la estructura de la explotación, las características socioeconómicas de los agricultores, sus actitudes, opiniones y comportamiento y los mercados entre otras razones. Este estudio pretende identificar los factores y las barreras que afectan la adopción por parte de los agricultores de varias Soluciones de Agricultura Circular utilizando un cuestionario semiestructurado sobre una muestra exploratoria de agricultores en 5 países de la UE. Los resultados preliminares muestran que la aceptación está muy relacionada con las motivaciones y objetivos económicos de los agricultores. El coste de inversión, la tasa de retorno, el apoyo institucional, el riesgo y la actitud ambiental juegan un papel relevante en la decisión final. Los resultados de las preferencias de adopción pueden ayudar a los políticos a diseñar medidas y herramientas más específicas y eficientes que puedan ayudar a los agricultores a enfrentar los desafíos ambientales y las necesidades sociales actuales

Practice abstract 47

Short title (in English):

Factors influencing farmer adoption of sustainable behaviours

Short summary for practitioners (in English):

Modern practices of industrial farming, such as mineral fertilization, have caused concerns regarding degradation of agricultural land and water bodies in Europe. Different farm management strategies exist to reduce the impact of mineral fertilization while preserving soil productivity. A recent review of 23 scientific articles published in the last 17 years summarized main factors and conditions affecting EU farmers’ adoption of such popular sustainable practices as organic farming, manure treatment technologies and manure fertilization, as well as soil and water conservation methods. Among the main findings is the one showing a significant impact of farmers’ environmental and economic attitudes on the adoption of organic farming, although there is a lack of evidence of their impact on adopting manure treatment and conservation measures. It was revealed that environmentally oriented farmers have better chances to become organic producers than farmers with a strong economic orientation. Similarly, older and better educated farmers are found to be more prone to organic farming adoption, but not adoption of other reviewed technologies. There is also very limited evidence that farm physical characteristics or technological attributes may affect adoption of new technologies by farmers. To craft better policies for the development of sustainable agriculture, policy makers have to learn directly from the experiences of successful farmers who adopted these technologies despite the lack of governmental support or adverse climate.

Short title (native language):

Factors influencing farmer adoption of sustainable behaviours

Short summary for practitioners (native language):

Practice abstract 48

Short title (in English):

Sustainable food consumption behaviors

Short summary for practitioners (in English):

Sustainable food consumption behaviors include various activities such as purchasing and consumption of sustainably produced food, for example, organic or free-range food. In addition, all routines contributing to reduction in household food waste can be also treated as sustainable behaviors. It is theoretically assumed that consumer personal attitudes, societal norms, and the ability to control own behavior may govern people’s intentions to consume in a sustainable way. A preliminary review of 28 consumer studies in Europe has revealed that both the consumer attitudes and societal norms towards organic food are the two important factors that define people’s intention to purchase or consume organic production. On the other hand, people’s ability to control own behavior was not found to affect either their intention to consume or consumption itself in a definite way. Several studies also found that Europeans may buy or consume organic food being guided by certain moral norms or the sense of self-identity. In terms of food waste behavior, this review found an important role that consumer attitudes play in food waste reduction behavior, while the effect of societal norms on the intention to reduce waste was rather less pronounced. Also, the consumer’s ability to control their food waste behavior, through such means as refrigeration or efficient cooking, should be helpful in keeping the levels of household waste low. Policy makers who plan to stimulate the demand for organic food in Europe as part of the Green Deal strategy, may take these results into account to design more targeted information campaigns.

Short title (native language):

Sustainable food consumption behaviors

Short summary for practitioners (native language):

Practice abstract 49

Short title (in English):

Feeding-related methane emissions from dairy farms in the Lungau region

Short summary for practitioners (in English):

The methane conversion factor (MCF) expresses the percentage of gross energy emitted via enteric methane. This energy can therefore not be used for animal metabolism. The MCF is internationally standardized by IPCC and ranges from 5.7 to 6.5 % for dairy cows, depending on their milk yield. However, these standardized values are rough estimations and disregard crucial influencing factors like, e.g., feed quality. Within a respiration chamber trial, dairy cows at AREC Raumberg-Gumpenstein were fed a typical ration for the case study region Lungau. The ration consisted of grass silage and hay (each 50%) of medium to high quality and contained 9.5% concentrate on average. Based on the results of this trial, we calculated a new MCF adjusted to the typical feeding regime in the case study region Lungau. This new MCF (5.75 %) was used to model the enteric methane emissions of dairy cows on 22 organic dairy farms in the case study region Lungau and compare the estimated emissions with the modeled methane emissions using the default MCF from IPCC (6.5 %). Results showed high heterogeneity in enteric methane emissions depending on the farms' herd size, and values ranged from 3,612 (farm 22; 26 dairy cows) to 401 kg CH4 (farm 20; 4 dairy cows). Compared to the results estimated with the default MCF (6.5 %), the use of the new MCF (5.75 %) resulted in an average reduction of enteric methane emissions of 13 %. Further research at AREC Raumberg-Gumpenstein will focus on verifying these first results, and methane emissions will also be estimated for other (more intensive) Austrian production systems.

Short title (native language):

Fütterungsbedingte Methanemissionen von Milchviehbetrieben aus dem Lungau

Short summary for practitioners (native language):

Ein bestimmter Prozentsatz der von Wiederkäuern aufgenommenen Energie, wird in Form von Methan wieder ausgeschieden. Dieser Prozentsatz wird durch den Methankonversionsfaktor ausgedrückt (MCF). Der MCF ist vom IPCC international standardisiert und liegt für Milchkühe je nach Milchleistung zwischen 5,7 und 6,5 %. Diese standardisierten Werte sind grobe Schätzungen und lassen entscheidende Einflussfaktoren wie z.B. die Futterqualität außer Acht. Im Rahmen eines Respirationskammerversuchs wurden Milchkühe mit einer für die Projektregion Lungau typischen Ration gefüttert. Die Ration bestand aus Grassilage und Heu (je 50 %) und enthielt im Durchschnitt 9,5 % Kraftfutter. Basierend auf den Ergebnissen dieses Versuches wurde ein neuer MCF berechnet, der an das typische Fütterungsregime in der Case Study Region Lungau angepasst ist. Dieser neue MCF (5,75 %) wurde verwendet, um die enterischen Methanemissionen von Milchkühen auf 22 Bio-Milchviehbetrieben in der Projektregion Lungau zu modellieren und die geschätzten Emissionen mit den modellierten Methanemissionen unter Verwendung des Standard-MCF von IPCC (6,5 %) zu vergleichen. Die Ergebnisse zeigen eine hohe Heterogenität der enterischen Methanemissionen in Abhängigkeit von der Herdengröße der Betriebe. Die Werte reichen von 3.612 (Betrieb 22; 26 Milchkühe) bis 401 kg CH4 (Betrieb 20; 4 Milchkühe). Verglichen mit den Ergebnissen, die mit dem Standard-MCF (6,5 %) geschätzt wurden, führte die Verwendung des neuen MCF (5,75 %) zu einer durchschnittlichen Reduzierung der enterischen Methanemissionen um 13 %. Im Zuge von weiterführenden Untersuchungen sollen diese ersten Ergebnisse überprüft und auch intensivere österreichische Produktionssysteme modelliert werden.

Practice abstract 50

Short title (in English):

Production and emission parameters of two different dairy cow rations

Short summary for practitioners (in English):

Two rations differing in forage composition and concentrate proportion were fed to Holstein Friesian and Simmental dairy cows to evaluate daily feed and gross energy intake, milk yield, and methane emission. Ration A (typical Austrian ration) consisted of 40% grass silage, 30% maize silage, and 30% hay, and the concentrate proportion was 24% on average. Ration B (typical ration for case study region Lungau) was a mixture of grass silage and hay (each 50%) and contained 9.5% concentrate on average. Forage was of medium to high quality, and concentrate was a mixture of cereals and by-products. Cows fed ration B had 2 kg lower daily dry matter intake and 49.3 MJ lower gross energy intake. As a consequence, daily milk yield was also 5.4 kg lower than in cows offered ration A. Furthermore, the lower feed intake of cows fed the typical Lungau ration (264.5 g) resulted in lower methane production per day compared to ration A (309.7 g). However, cows yielded similar amounts independent of the ration regarding methane production per kg energy-corrected milk yield. Based on the results on gross energy intake and daily methane production, methane conversion factors were calculated for both rations according to IPCC. The methane conversion factor gives the percentage of gross energy emitted via methane. This energy can therefore not be used for animal metabolism. Feeding ration B resulted in a methane conversion factor of 5.65 while it was 6.16 in cows fed ration A. This result shows that low methane conversion factors can be achieved if medium to high quality forage is fed and low amounts of concentrates are supplemented, while most former studies found decreasing methane conversion factor with increasing concentrate proportion in the ration.

Short title (native language):

Produktions- und Emissionsparameter von zwei Milchviehrationen

Short summary for practitioners (native language):

Zwei Rationen (unterschiedliche Grundfutterzusammensetzung und Kraftfutteranteil) wurden an Holstein Friesian- und Fleckvieh-Milchkühe verfüttert um Futteraufnahme, Milchleistung und Methanemissionen zu messen. Ration A (typische österreichische Ration) enthielt 40 % Grassilage, 30 % Maissilage und 30 % Heu bei 24 % Kraftfutteranteil. Ration B (typische Ration für Modellregion Lungau) bestand aus je 50 % Grassilage und Heu bei 9,5 % Kraftfutteranteil. Das Grundfutter hatte mittlere bis hohe Qualität und das Kraftutter bestand aus Getreide und Nebenprodukten. Kühe, die Ration B erhielten, fraßen 2 kg weniger Trockenmasse und 49,3 MJ weniger Bruttoenergie pro Tag. Daher gaben sie auch 5,4 kg weniger Milch als die mit Ration A gefütterten Kühe. Weiters führte die geringere Futteraufnahme zu einer niedrigeren täglichen Methanproduktion der Kühe mit Ration B (264,5 g) im Vergleich zu Ration A (309,7 g). Die Methanproduktion je kg Energie-korrigierter Milch unterschied sich jedoch nicht zwischen den Rationen. Basierend auf den Ergebnissen dieser Untersuchung wurde für beide Rationen der Methankonversionsfaktor nach IPCC berechnet. Der Methankonversionsfaktor gibt an, welcher Anteil der Bruttoenergie in Form von Methan ausgeschieden wird und somit nicht für den Stoffwechsel der Kuh zur Verfügung steht. Dieser Faktor war bei Ration B 5,65 und bei Ration A 6,16. Dieses Ergebnis zeigt, dass bei Verfütterung von mittel- bis hochqualitativem Grundfutter und geringen Kraftfuttermengen niedrige Methankonversionsfaktoren erreicht werden, während in den meisten früheren Studien abnehmende Methankonversionsfaktoren mit steigendem Kraftfutteranteil festgestellt wurden.

Practice abstract 51

Short title (in English):

Effect of organic amendments on soil fertility and organic carbon stocks in agricultural topsoil and subsoil

Short summary for practitioners (in English):

Organic amendments such as cattle-manure, slurry or biogas digestate have been widely applied to maintain soil organic carbon (OC) and nutrient contents, aiming at improving soil fertility and crop production. However, sustainable effects of organic amendments on topsoil and particularly subsoil OC stocks, and on soil nutrient cycling are still debated. In the Circular Agronomics EU project, we study the effects of mineral and organic fertilisation after seven years of application (i.e. manure, pig slurry and biogas digestate) on topsoil and subsoil OC, nutrient contents and soil structure, in a sandy Cambisol (IASP, Germany). To this end, we took soil cores down to one meter depth in a field experiment and quantified soil OC, nitrogen and nutrient contents (e.g., nitrate, available phosphorus). To detect the potential effect of the fertilization on the soil structure, we determined soil aggregate size distribution. We found that organic fertilization increased soil OC stocks from 1.16 to 1.46 kg m-2 at 0-10 cm compared with mineral fertilization. The application of biogas digestate and mineral fertilizer resulted in similar aggregation patterns down to 80 cm, and both treatments presented higher contribution of small aggregates (< 250 µm), compared with the no-fertilization treatment. For similar sandy soils, naturally having low OC and nutrients contents, the application of organic amendments can enhance soil fertility and OC storage at the medium term.

Short title (native language):

Auswirkung organischer Veränderungen auf die Bodenfruchtbarkeit und die organischen Kohlenstoffvorräte im landwirtschaftlichen Ober- und Unterboden

Short summary for practitioners (native language):

Organische Zusätze wie Rindermist, Gülle oder Biogas-Gärreste sind weit verbreitet, um den Gehalt an organischem Kohlenstoff (OC) und Nährstoffen im Boden aufrechtzuerhalten, mit dem Ziel, die Bodenfruchtbarkeit und die Pflanzenproduktion zu verbessern. Die nachhaltigen Auswirkungen organischer Veränderungen auf den Oberboden und insbesondere der OC-Bestände im Unterboden, sowie auf den Nährstoffkreislauf des Bodens, werden jedoch noch diskutiert. Im EU-Projekt Circular Agronomics untersuchen wir in einem sandigen Cambisol (IASP, Deutschland). Dazu haben wir in einem Feldversuch Bodenkerne bis zu einer Tiefe von einem Meter entnommen und Boden-OC-, Stickstoff- und Nährstoffgehalte (z. B. Nitrat, verfügbarer Phosphor) quantifiziert. Um den möglichen Einfluss der Düngung auf die Bodenstruktur zu erkennen, haben wir die Größenverteilung der Bodenaggregate bestimmt. Wir fanden heraus, dass organische Düngung die OC-Bestände im Boden von 1,16 auf 1,46 kg m-2 bei 0-10 cm im Vergleich zu mineralischer Düngung erhöhte. Die Anwendung von Biogasgärresten und Mineraldünger führte zu ähnlichen Aggregationsmustern bis zu 80 cm. Beide Behandlungen zeigten einen höheren Beitrag kleinerer Aggregate (< 250 µm) im Vergleich zur Behandlung ohne Düngung. Bei ähnlichen Sandböden, die von Natur aus niedrige OC- und Nährstoffgehalte aufweisen, kann die Anwendung organischer Zusätze mittelfristig die Bodenfruchtbarkeit und OC-Speicherung verbessern.

Practice abstract 52

Short title (in English):

On-field and lab applications of light reflectance spectroscopy methods for organic carbon and nitrogen monitoring

Short summary for practitioners (in English):

Monitoring contents and distribution of soil physico-chemical properties can support decisions for sustainable agricultural production systems. Visible-Near-Infrared (Vis-NIR) spectroscopy is a method using the light reflectance properties of individual materials in the range of visible and near infrared wavelengths. This method can reduce the time and budget constraints of conventional laboratory methods. It enables soil surveyors to increase sampling density without adding substantial costs. There are two main approaches to quantify soil properties by Vis-NIR spectroscopy.
1. Classical single point Vis-NIR spectrometers are designed for easy operations, and provide instant results with minimal sample preparation.
2. Hyperspectral imaging using a high-resolution camera, which is applied in the Circular Agronomics EU project (CA) to predict soil organic carbon (OC) and nitrogen (N) contents at a fine scale.
In the CA project, we collected intact core samples for scanning with a hyperspectral camera (Hyspex VNIR-1800 camera; Norsk elektro optikk, Norway 400-990 nm, 53*53 µm² per pixel). We applied machine-learning to model the OC and N contents at a fine scale. We successfully applied this approach to show the OC and N depth-distribution down to one meter in a 7-year field-trial testing various types of organic fertilization in a sandy Cambisol (IASP, Germany).

Short title (native language):

Feld- und Laboranwendungen von Lichtreflexionsspektroskopiemethoden zur Überwachung von organischem Kohlenstoff und Stickstoff

Short summary for practitioners (native language):

Die Überwachung des Inhalts und der Verteilung der physikalisch-chemischen Eigenschaften des Bodens kann Entscheidungen für nachhaltige landwirtschaftliche Produktionssysteme unterstützen. Visible-Near-Infrared (Vis-NIR) Spektroskopie ist eine Methode, die die Lichtreflexionseigenschaften einzelner Materialien im sichtbaren und nahen Infrarot-Wellenlängenbereich nutzt. Diese Methode kann die Zeit- und Budgetbeschränkungen herkömmlicher Labormethoden reduzieren. Es ermöglicht Bodenvermessern, die Probenahmedichte ohne erhebliche Kosten zu erhöhen. Es gibt zwei Hauptansätze, um Bodeneigenschaften durch Vis-NIR-Spektroskopie zu quantifizieren.
1. Klassische Einpunkt-Vis-NIR-Spektrometer sind auf einfache Bedienung ausgelegt und liefern sofortige Ergebnisse bei minimaler Probenvorbereitung.
2. Hyperspektrale Bildgebung mit einer hochauflösenden Kamera, die im EU-Projekt Circular Agronomics (CA) eingesetzt wird, um den Gehalt an organischem Kohlenstoff (OC) und Stickstoff (N) im Boden im feinen Maßstab vorherzusagen.
Im Projekt CA sammelten wir intakte Bohrkerne zum Scannen mit einer Hyperspektralkamera (Hyspex VNIR-1800 Kamera; Norsk elektro optikk, Norwegen 400-990 nm, 53*53 µm² pro Pixel). Wir haben maschinelles Lernen angewendet, um die OC- und N-Gehalte in einem feinen Maßstab zu modellieren. Wir haben diesen Ansatz erfolgreich angewendet, um die OC- und N-Tiefenverteilung bis auf einen Meter in einem 7-jährigen Feldversuch zu zeigen, indem verschiedene organische Düngungen in einem sandigen Cambisol (IASP, Deutschland) getestet wurden.

Practice abstract 53

Short title (in English):

Biogas from manure: from a problem to an opportunity

Short summary for practitioners (in English):

Livestock production has increased in recent decades. It has gone from small family farms to large intensive livestock farms. These changes have caused an exponential increase of livestock manure in certain European territories. However, manure can be a business opportunity for farmers. Associating a biogas plant with a farm brings multiple environmental and economic benefits. The emission of greenhouse gases is reduced, and biogas is generated, which is composed of approximately 65% methane. Biogas is used as fuel in cogeneration engines that generate electricity and thermal energy from renewable sources. The produced energy reduces the economic costs of the farm since it can be self-consumed or sold to the distribution network. Although the initial investment cost is generally high, the amortization is around seven years. The effluent derived from the process is called digestate. The odour of the digestate is reduced by 95% in comparison with the raw manure. As developed in the Circular Agronomics project, the digestate can be subjected to a solid-liquid separation, obtaining a solid fraction with high fertilizer properties that can be dried or composted and reused in territories far from areas with high livestock density. The liquid fraction is used to fertilize fields close to the farm or it can also be treated to obtain fertilizers such as ammonium sulfate. In this way, a real and environmentally sustainable circular economy is promoted.

Short title (native language):

Biogás a partir de purines: del problema a la oportunidad

Short summary for practitioners (native language):

La intensificación de la ganadería está siendo sustancial en las últimas décadas. Se ha pasado de pequeñas explotaciones familiares a grandes explotaciones ganaderas. Estos cambios han provocado un aumento exponencial de deyecciones ganaderas en determinados territorios europeos. Estas deyecciones, bien gestionadas, pueden ser una oportunidad de negocio para los granjeros. Asociar una planta de biogás a una granja trae múltiples beneficios tanto medioambientales como económicos. Se reduce la emisión de gases de efecto invernadero, se genera biogás, que está compuesto aproximadamente por un 65% de metano. El biogás es utilizado como combustible en motores de cogeneración que generan energía eléctrica y energía térmica de origen renovable. La energía generada reduce los costes económicos de la granja, ya que se puede autoconsumir o vender a la red de distribución. Aunque la inversión inicial a realizar tiene un coste generalmente elevado, la amortización de dicha inversión se sitúa alrededor de los siete años. Por otra parte, las deyecciones ganaderas ya digeridas pasan a ser denominadas digestato. Este digestato que ha reducido en un 95% los olores del purín fresco. Tal y como se desarrolla en el proyecto Circular Agronomics, el digestato puede someterse a una separación sólido-líquido, obteniendo una fracción sólida con altas propiedades fertilizantes que puede ser secada o compostada y reaprovechada en territorios lejanos de las zonas con alta densidad ganadera. La fracción líquida se utiliza para fertilizar los campos cercanos a la explotación origen o también puede ser tratada para obtener fertilizantes como el sulfato amónico. De este modo, se potencia una economía circular real y medioambientalmente sostenible.

Practice abstract 54

Short title (in English):

Phytotoxicity test in lettuce seeds and seedlings with digestate products

Short summary for practitioners (in English):

When using fertilizer products coming from organic waste such as manure for edible crops, previous phytotoxicity assays can help to elucidate whether the product is suitable for an optimal plant grow. Within the Circular Agronomics project, phytotoxicity assays was executed in lettuce seeds and seedlings with raw digestate (D) and dried digestate (DD) after the solar drying process. The germination index (Gj) was measured according to the OECD guidelines. Extracts of each product were then diluted to 100%, 75%, 50%, 25%, 15% and 0% in distilled water and the germination index was calculated. Results show that a dilution ratio of 15% of D and DD attained germination index values higher than 70 %, which are indicative of no phytotoxicity. The electrical conductivity was determined to be the main problem related to germination. Our preliminary conclusion is therefore that digestate without the appropriate dilution is unsuitable to be a fertilizer for edible crops. An alternative approach to improve the quality of the dried product as fertilizer could be a solid-liquid separation process prior to drying. Such an approach would improve the NPK concentration of this fraction, while the dissolved salts would be in a higher concentration in the clarified fraction.

Short title (native language):

Ensayo de fitotoxicidad en semillas y plántulas de lechuga con digestato de purín

Short summary for practitioners (native language):

Cuando se utilizan productos fertilizantes provenientes de residuos orgánicos como los purines para cultivos comestibles, ensayos previos de fitotoxicidad pueden ayudar a dilucidar si el producto es adecuado para un cultivo óptimo de la planta. Dentro del proyecto Circular Agronomics, se realizaron ensayos de fitotoxicidad en semillas y plántulas de lechuga con digestato crudo (D) y digestato seco (DD) luego del proceso de secado solar. El índice de germinación (Gj) se midió de acuerdo con las directrices de la OCDE. Los extractos de cada producto se diluyeron luego al 100%, 75%, 50%, 25%, 15% y 0% en agua destilada y se calculó el índice de germinación. Los resultados muestran que una dilución del 15% para D y DD alcanzó valores de índice de germinación superiores al 70%, indicativo de ausencia de fitotoxicidad. Se determinó que la conductividad eléctrica es el principal problema relacionado con la germinación. Nuestra conclusión preliminar es, por tanto, que el digestato sin la dilución adecuada no es apropiado como fertilizante para cultivos comestibles. Un enfoque alternativo para mejorar la calidad del producto seco como fertilizante podría ser un proceso de separación sólido-líquido antes del secado. Tal enfoque mejoraría la concentración de NPK de esta fracción, mientras que las sales disueltas estarían en una concentración más alta en la fracción clarificada.

Practice abstract 55

Short title (in English):

Microfiltered digestate in subsurface drip irrigation (SDI)

Short summary for practitioners (in English):

The microfiltered digestate can be conveniently used as a fertilizer, mixed with irrigation water in fertigation systems. The particles with a diameter greater than 50 microns are almost completely excluded by the microfilter specially developed by Saveco WAMgroup, and cannot clog nozzles or drippers.
The optimal agronomic use of the microfiltered fraction is the distribution on growing crops, because it contains most of the nitrogen in ammoniacal form, which is ready-to-use for plant nutrition.
In the Circular Agronomics project, microfiltration tests and the use of microfiltered digestate in fertigation, by means of Netafim drip lines buried 25 cm deep (SDI – subsurface drip irrigation), were organized at CAT Correggio biogas farm (Emilia-Romagna region, Italy). The fertigation system includes a safety filter and a working pressure control system.
In 2019 the fertigation trials were conducted on maize obtaining good yields of around 20 DM tons/ha, comparable to those of the Business as Usual scenario based on sprinkler irrigation and use of raw urea. In 2020 sorghum was cultivated, with the aim of verifying the possibility of obtaining a double harvest, in summer and autumn. The trial showed that it may be possible to harvest the sorghum twice over a six-month period (May-October), in this way achieving a production of 20 DM tons/ha. The sorghum benefited from available water to full express itself, with total nitrogen removals close to those of maize (around 300 kg N/ha).

Short title (native language):

PA1. Digerito microfiltrato nell'irrigazione a goccia sotterranea

Short summary for practitioners (native language):

Il digestato microfiltrato può essere convenientemente utilizzato come fertilizzante in sistemi di fertirrigazione, miscelato con l'acqua irrigua. Il microfiltro appositamente sviluppato da Saveco WAMgroup permette di escludere quasi completamente le particelle di diametro superiore a 50 micron per non intasare ugelli o gocciolatori.
L'uso agronomico ottimale della frazione microfiltrata consiste nella distribuzione su colture in fase di crescita, perché la maggior parte dell’azoto è presente in forma ammoniacale prontamente disponibile per le piante.
In Circular Agronomics, sono state organizzate prove di microfiltrazione con successivo impiego del digestato microfiltrato in fertirrigazione, per mezzo ali gocciolanti Netafim interrate a 25 cm di profondità (SDI - subsurface drip irrigation), presso l'azienda CAT Correggio (Emilia-Romagna) che dispone di impianto di biogas.
Nel 2019 le prove di fertirrigazione sono state condotte su mais ottenendo buone rese di circa 20 DM ton/ha, paragonabili a quelle dello scenario Business as Usual basato su irrigazione a pioggia e impiego di urea. Nel 2020 è stato coltivato il sorgo, con l'obiettivo di ottenere un doppio raccolto. La prova ha dimostrato che è possibile raccogliere il sorgo due volte in un arco temporale di sei mesi (maggio-ottobre), ottenendo così una produzione di 20 tonnellate DM/ha. Il sorgo, beneficiando dell’apporto idrico, ha mostrato un'asportazione complessiva di azoto vicina a quella del mais (circa 300 kg N/ha).

Practice abstract 56

Short title (in English):

Ammonia Washing Machine to recover N from the air of pig house reducing ammonia emissions

Short summary for practitioners (in English):

Ammonia emissions from the house of pigs are due to the faeces and urine on the surfaces and the presence of slurry under the slatted floor. The need to improve the animal welfare, the health of workers and to reduce ammonia emissions from pig livestock was the motivation behind the "Ammonia Washing Machine" EIP-AGRI Operational Group, which created and tested an air treatment system to catch ammonia emissions from the pig house.
The prototype takes the ammonia-rich air from the pig house through the suction ducts installed under the slatted floor to improve the inside air quality, especially in those housing conditions (weaning piglets) or climatic conditions (winter) where air changes are limited. The treatment is based on the chemical absorption of ammonia present in the airflow by counter-current acid washing with sulfuric acid.
An important nutrient such as nitrogen, which in the form of ammonia emitted into the atmosphere causes health and environmental issues, can be recovered and give life to a fertilizer (ammonium-sulphate solution) in a perspective of "nutrient recovery and reuse". The activity has shown that is possible to recover 2.4 kg NH3 per animal place per year (394 litres of ammonium sulphate solution per t of live weight per year). The good nitrogen content (3.5%), of which 99% present as ammonia form, and the very low solids content are characteristics that make this solution a good nitrogen source for fertilizing purposes, in particular for fertigation.

Short title (native language):

Lavatrice ad ammoniaca per recuperare N dall'aria della stalla riducendo le emissioni di ammoniaca

Short summary for practitioners (native language):

La necessità di migliorare il benessere degli animali, la salute dei lavoratori e di ridurre le emissioni di ammoniaca dagli allevamenti suini è stata la motivazione alla base del Gruppo Operativo EIP-AGRI "Ammonia Washing Machine", che ha sviluppato e testato un sistema di trattamento dell'aria per catturare le emissioni di ammoniaca.
Il prototipo preleva l'aria ricca di ammoniaca dalle sale d’allevamento dei suini attraverso condotte di aspirazione installate sotto il pavimento fessurato per migliorare la qualità interna dell'aria, soprattutto in quelle fasi stabulative (svezzamento) o climatiche (inverno) dove i ricambi d'aria sono limitati. Il trattamento si basa sull'assorbimento chimico dell'ammoniaca presente nel flusso d'aria mediante lavaggio in controcorrente con acido solforico.
Un nutriente importante come l'azoto, che sotto forma di ammoniaca emessa in atmosfera causa problemi sanitari e ambientali, può essere recuperato e dare vita ad un fertilizzante (soluzione di solfato di ammonio) in un'ottica di "recupero e riutilizzo dei nutrienti". L’attività ha dimostrato che è possibile recuperare 2,4 kg di NH3 per posto animale all'anno (394 litri di soluzione di solfato di ammonio per t di peso vivo all'anno). Il buon contenuto di azoto (3,5%), di cui il 99% presente in forma ammoniacale, ed il minimo contenuto di solidi sono caratteristiche che fanno di questa soluzione una buona fonte di azoto ai fini fertilizzanti, in particolare per l’impiego in fertirrigazione.

Practice abstract 57

Short title (in English):

Efficiency of a centrifugal separator for manure management

Short summary for practitioners (in English):

The efficiency of the solid-liquid separation depends on several factors: the type of separator, the type of manure to be treated (type of animal and stage of the life cycle), the flow rate or the amount of organic matter. In this sense, centrifuge separation systems, although more expensive, are much more efficient than screw press systems, but require the addition of polymers. The N/P ratio in the liquid fraction increases by 708%, compared to an increase of 29% when using a filter press. The highest separation efficiencies are usually obtained when working at low flow rates and organic matter contents above 5%, which is directly related to proper water management in the farm. It has been determined that the separation efficiency to the solid fraction with a centrifuge, at a flow rate of 4 m3/h, is approximately 50% for N and 95% for P. In economic terms, for 17,600 m3 of manure to be treated, with N and P content of 3 and 1.04 kg/m3, respectively, and considering additional costs such as energy costs, depreciation or the construction of specific structures, the cost per kg of N and P treated is approximately 1.96 and 4.96 euros, respectively, for a sieve and screw press system, and 2.34 and 4.43 euros, for a combined screw press and centrifuge system.

Short title (native language):

Eficiencia de un separador tipo centrífuga para la gestión del purín

Short summary for practitioners (native language):

La eficiencia de separación sólido-líquido depende del tipo de separador, el tipo de purín (tipo de animal y fase del ciclo de vida), el caudal de trabajo o la cantidad de materia orgánica. En este sentido, los sistemas de separación mediante centrífuga, si bien son más costosos, presentan una eficiencia mucho mayor que los sistemas filtro prensa, pero requieren de la adición de polímeros. La relación N/P en la fracción líquida se incrementa en un 708%, frente al 29% de incremento cuando se utiliza un filtro prensa. Las mayores eficiencias de separación suelen obtenerse al trabajar a bajo caudal y a contenidos de materia orgánica por encima del 5%, lo que está directamente relacionado con una correcta gestión del agua en la granja. Se ha determinado que la eficiencia de separación de una centrífuga a la fracción sólida, a un caudal de 4 m3/h, es de aproximadamente un 50% para el N y un 95% para el P. En términos económicos; para un volumen de purín a tratar de 17.600 m3, con un contenido en N y P de 3 y 1,04 kg/m3, respectivamente, y considerando costes adicionales como el gasto energético, la amortización o la construcción de estructuras específicas, el coste por kg de N y P tratado es de aproximadamente 1,96 y 4,96 euros, respectivamente, para un sistema de tamiz y filtro prensa, y de 2,34 y 4,43 euros, para un sistema combinado de filtro prensa y centrífuga.

Practice abstract 58

Short title (in English):

P-recovery by anaerobic stage pH control without reagents

Short summary for practitioners (in English):

Phosphorus (P) recovery via struvite formation requires addition of the limiting reagent usually magnesium (Mg). The other key process parameter is pH. However soybean processing wastewater has an interesting feature that instead of magnesium, phosphorus is the limiting parameter. Anaerobic stage effluent analysis reflected the P levels in the range of 3 – 3.5 mM whilst for Mg around 6 mM. The implemented wastewater treatment (lagoon) resulted in a pH at the lower spectrum of anaerobic operation of 6.5 to 7. A simple pH increase by either addition of some caustic reagent (NaOH) or induced by CO2 stripping resulted in a significant reduction of the P level (PO4-P) from 3-3.5 mM down to 1 mM or concentration wise from about 100 ppm PO4-P down to 30 ppm. The latter approach of inducing the pH increase by CO2 stripping is very interesting as no additional reagents are required. However, this opportunity only arose due to the low pH operation of the anaerobic stage unlike the modern anaerobic treatment systems. High pH systems develop the risk of unwanted struvite scaling in reactor piping and/or reactor internals causing serious maintenance issues. However for the particular case of anaerobic processing soybean wastewater the situation becomes profitable. The anaerobic stage can be run at pH suboptimal condition but still achieve the needed conversion into biogas, NH4-N and PO4-P and reactive Mg. Adding a CO2 stripper with struvite recovery is known and a proven technology. The practical case under the Circular Agronomics project can potentially yield 500 to 600 tonnes struvite/year. Recent trails for several crops shows that struvite acts as a slow release fertilizer (low dosage 20 kg/ha) in close interaction with plant root exudates and soil microbiology. Such a type of slow release precision fertilizers could be key contributor to reduces GHG emissions currently resulting from standard fertilizer production and use.

Short title (native language):

P-herstel door anaërobe fase pH-regeling zonder reagentia

Short summary for practitioners (native language):

Fosfor recuperatie door struvietvorming vereist de toevoeging van het beperkende reagens, magnesium. Afvalwater van de verwerking sojabonen heeft het kenmerk dat niet magnesium maar fosfor de beperkende parameter is. Effluent analyse toont aan dat voor de anaërobe fase de fosfaat concentratie ligt op 3 - 3,5 mM ligt en magnesium 6 mM. Het type anaërobe behandeling kent een pH van 6,5 tot 7. Een pH-verhoging door toevoeging van alkalisch reagens (NaOH) of induceren van een pH-verhoging door CO2-stripping resulteerde in een verlaging van het fosfaat gehalte (PO4-P) van 3-3,5 mM tot 1 mM of qua concentratie van ongeveer 100 ppm PO4-P tot 30 ppm PO4-P. Induceren van de pH-verhoging door CO2-strippen vereist geen toevoeging van chemicaliën. Dit maakt het proces zeer interessant omdat er niet met chemicaliën moet worden omgegaan en er geen verhoging is van het zoutgehalte (bijv. chloriden). Men kan verwachten dat in hoog technologische anaërobe behandelingssystemen de pH van de reactor hoger zal zijn. Als de omstandigheden juist zijn (voornamelijk in termen van pH), is er risico op de vorming van ongewenste struviet vorming. Dit laatste kan ernstige onderhoudsproblemen veroorzaken. De anaërobe fase kan worden uitgevoerd bij een suboptimale pH-conditie, maar toch wordt de benodigde omzetting van organische stoffen in biogas bereikt, waarbij gebonden N, P en Mg worden omgezet in NH4-N en PO4-P en reactief Mg. Voordeel is dat het primaire influent relatief zuur is en kan bijdragen aan de anaërobe pH-regeling in de anaerobe reactor. Gebruik van precisiemeststoffen met langzame afgifte kan een belangrijke bijdrage leveren aan de vermindering van de broeikasgasemissies.

Practice abstract 59

Short title (in English):

P-recovery by K-struvite after aerobic stage

Short summary for practitioners (in English):

Fertilizer reuse will be mandatory in future to ensure food safety as phosphorus is a limited resource and is essential for food/feed production. Besides nitrogen, the other key fertilizer compound is potassium and it is a mined resource with limited supply. Although Potassium is not major constituent of biomass unlike N and P, yet is a key element in terms of metabolic activity as it ensures good cation/anion equilibria and transmembrane transport mechanisms. The latter is inherently coupled with the high water solubility of K. This high water solubility is a challenge as precipitating K as a solid is limited to only a few water insoluble K-salts. One of these few water insoluble K-salt is a struvite analog where NH4 is replaced by K. The absence of NH4-N is vital to produce K-struvite thus it is typically produced after the aerobic stage considering substantial amount of reactive magnesium is available in the wastewater. However the required pH for K-struvite formation is near to 9 so an additional pH correction is needed. Trials done with the aerobic stage effluent spiked with extra phosphate showed that reductions from 100 ppm to 30-40 ppm of PO4-P are possible with pH control and limited or no extra reagent addition. However, the resulting residual PO4-P levels still exceed the current discharge levels for surface water so an additional tertiary PO4-P removal will be needed. An approach to avoid this is to apply the K-struvite formation on purified wastewater that will be reclaimed for reuse. The interest for farmers is the availability of a slow release K-containing fertilizer compared to the standard chemical fertilizer. The combination of both NH4-struvite and K-struvite enables to produced a more customized fertilizer with an improved NPK ratio.

Short title (native language):

P-herstel door K-struviet na aërobe stadium

Short summary for practitioners (native language):

Hergebruik meststoffen zal in de toekomst verplicht zijn om de voedselveiligheid te waarborgen, gezien fosfor een beperkte hulpbron is en essentieel is voor de productie van voedsel. Stikstof en kalium zijn de andere belangrijke meststoffen. Hoewel kalium geen hoofdbestanddeel van biomassa is, in tegenstelling tot N en P, is het toch een sleutelelement in termen van metabolische activiteit het zorgt voor goede kation/anion-evenwichten en transmembraantransportmechanismen. Dit laatste is gekoppeld aan de hoge wateroplosbaarheid. Deze oplosbaarheid in water is een uitdaging gezien het neerslaan van K als een vaste stof beperkt is tot enkele in water onoplosbare K-zouten. Een weinige in water onoplosbare K-zout is een struviet analoog. De afwezigheid van NH4-N is van vitaal om K-struviet te produceren, dus het wordt meestal geproduceerd na de aerobe fase. De vereiste pH voor de vorming van K-struviet is bijna 9, dus een extra pH-correctie is nodig. Proeven gedaan met het effluent van de aerobe fase, verrijkt met extra fosfaat, toonden reducties van 100 ppm naar 30-40 ppm PO4-P zijn met pH-regeling en beperkte of geen extra toevoeging van reagens. De resulterende resterende PO4-P-gehalten overschrijden nog de huidige lozingsniveaus voor oppervlaktewater, zodat een extra tertiaire PO4-P-verwijdering nodig is. Een aanpak om dit te voorkomen is vorming van K-struviet toe te passen op gezuiverd afvalwater dat wordt teruggewonnen voor hergebruik. Het belang voor boeren is de beschikbaarheid van een langzaam vrijkomende K-houdende meststof in vergelijking met de standaard kunstmest. De combinatie van zowel NH4-struviet als K-struviet maakt het mogelijk om een meer op maat gemaakte meststof te produceren met een verbeterde NPK-verhouding.

Practice abstract 60

Short title (in English):

Improving fertilizer use efficiency through a more diverse earthworm community

Short summary for practitioners (in English):

Struvite is one of the most interesting novel fertilizers of the circular agronomy. It can be produced from a variety of “waste” streams, including dairy waste, manure and sewage sludge. Struvite is increasingly considered as a promising phosphorus (P) fertilizer, which is especially interesting as the reserves of rock phosphate (the raw material for conventional P fertilizer) are limited. One of the potential drawbacks of struvite as a P fertilizer is its low solubility, which makes it a challenge to supply plants in time with the amounts of P they need for growth. However, it is possible that soil fauna may increase solubility through their activity, resulting in a potential positive effect of soil biodiversity on P use efficiency of struvite. Earthworms are particularly interesting in this regard, as we know from other studies that they can distribute fertilizer grains more envenly through the soil, bringing them potentially closer to plant roots and available for uptake. In a field experiment, we are currently testing to what extent earthworms may increase P uptake efficiency from struvite, and whether this effect changes with earthworm species or -diversity. We hope that our work, through making a link between faunal diversity and agronomic efficiency, will give some guidelines on how to make agriculture more circular though nurturing biodiversity.

Short title (native language):

Verbeteren van de efficiëntie van bemesting door een meer diverse regenwormen gemeenschap

Short summary for practitioners (native language):

Struviet is één van de meest veelbelovende nieuwe meststoffen voor de circulaire landbouw. Het kan gemaakt worden uit verschillende “afval” stromen, waaronder afval uit de zuivelindustrie, dierlijke mest en zuiveringsslib. Struviet wordt steeds meer gezien als een interessante fosfaat (P) meststof, en dat is interessant omdat de reserves van rots fosfaat (de ruwe grondstof van conventionele P meststoffen) eindig zijn. Eén van de mogelijke nadelen van struviet als meststof is dat het maar heel langzaam oplost, wat het lastig maakt om planten snel genoeg van voldoende P te voorzien. Het is echter mogelijk dat activiteit van bodemdieren de oplosbaarheid en P beschikbaarheid van struviet zou kunnen verhogen. Van met name regenwormen weten we uit andere studies dat ze meststofdeeltjes beter door de bodem kunnen verdelen, en daarbij wellicht ook dichter bij plantenwortels kunnen brengen. Momenteel testen we in een veldexperiment in hoeverre regenwormen de P efficientie van struviet kunnen verhogen, en of dit afhankelijk is van wormensoort en/of biodiversiteit. We hopen dat we met dit werk, dat een link probeert te leggen tussen wormen diversiteit en agronomische efficiëntie, richtlijnen kunnen geven over voor een meer circulaire landbouw door het verhogen van biodiversiteit.

Practice abstract 61

Short title (in English):

Can we decrease N2O emissions after fertilizer application by smart selection of plant species?

Short summary for practitioners (in English):

Nitrous oxide (N2O) is, with carbon dioxide and methane, one of the three main greenhouse gases that cause global warming. Unlike both other gases, N2O emissions are mostly emitted from soils, after application of nitrogen fertilizers. Emissions from managed grasslands are especially important in countries like The Netherlands. Many management practices to minimize N2O emissions have been proposed, mostly dealing with timing, rate and type of fertilizer application. Little attention has been paid to date on the effect of grassland species composition. From ecological studies in semi-natural grasslands, we know that a higher plant species composition can lead to fewer nutrient losses, especially if the plant species are very different in aspects such as rooting depth. In a series of experiments over the past few years, we have shown that a smart combination of grass and/or legume species may indeed lead to fewer N losses through N2O emissions and leaching. Currently, we are conducting a large field experiment to test whether this principle also works for circular fertilizers such as digestates and ammonium sulphate produced after vacuum degasification of digestate. Once completed, we hope that our results will provide useful suggestions on what species of plants to seed in order to contribute to a more circular agriculture with fewer losses to the environment of harmful substances.

Short title (native language):

Kunnen we N2O emissies na bemesting verlagen door een slimme selectie van plantensoorten?

Short summary for practitioners (native language):

Lachgas (N2O) is, met kooldioxide en methaan, één van de drie belangrijkste broeikasgassen die verantwoordelijk zijn voor klimaatsverandering. In tegenstelling tot beide andere gassen komt het grootste deel van de antropogene N2O emissie uit bodems, vooral na toediening van stikstof houdende meststoffen. Voor landen als Nederland zijn emissies uit intensief beheerd grasland vooral belangrijk. Er zijn al veel management maatregelen voorgesteld om N2O emissies te verminderen, die vooral betrekking hebben op timing, hoeveelheid en soort mest toediening. Tot nu toe was er maar weinig aandacht voor de rol van plantensoort samenstelling. Toch weten we uit ecologische studies in semi-natuurlijk grasland dat een grotere rijkdom aan plantensoorten kan leiden tot minder nutriënten verliezen, vooral als het gaat om planten die sterk verschillen in aspecten zoals bewortelingsdiepte. Gedurende de afgelopen jaren hebben we in een serie experimenten laten zien dat een slimme combinatie van grassen en vlinderbloemigen inderdaad tot een vermindering van N verliezen en N2O emissies kan leiden. Momenteel bestuderen we in een groot veldexperiment of dit principe ook werkt voor circulaire meststoffen zoals digestaten en ammoniumsulfaat dat uit digestaat gewonnen wordt door vacuum degasificatie. Na voltooiing van onze studie hopen we handvatten te kunnen geven over de soort plantencombinaties die moet worden ingezaaid om bij te dragen tot een meer circulaire landbouw en minder verliezen van schadelijke stoffen naar de omgeving.

Practice abstract 62

Short title (in English):

Application of electrospun nanofibrous membranes (ENM) for digestate pretreatment

Short summary for practitioners (in English):

Electrospun nanofibrous membranes (ENM) are proper alternative of recently used flat-sheet, tubular or ceramic membranes in the area of separation processes, e.g. filtration, mechanical pre-treatment, thickening. Unique technology of electrospinning production of nanofibrous membranes produces membranes with holes up to 200–400 nanometers to ensure efficient separation or thickening of media. Digestate is recently widely spread problematic solution that need to be handled before its other applications, e.g. sprinkling on the fields or utilization in composting. Our hypothesis verified thickening of digestate by ENMs. We worked with sample of 8 m2 of ENM and ca. 500 liters of digestate and membrane flux between 2-4 LMH. Digestate was thickened from 5.8 % TSS to 9.3% TSS during 15 hours of operation without necessary membrane backwash and addition of coagulants. We made balance of main nutritional elements (C, N, P, K) in raw digestate, membrane concentrate and membrane permeate. COD was reduced from 44 g/L to 9.2 g/L in permeate. Concentration of total nitrogen was reduced from 5.57 to 4.16 g/L in permeate showing 25% of nitrogen removal. N-NH4 has been reduced from 4.89 g/L to 3.52 g/L showing 18% N-NH4 removal. Total phosphorus was reduced from 234 mg/l to 74 mg/l in permeate showing 68% TP removal. Concentration of TK was 5.05 g/l and remained splitted the same for concentrate and permeate. Tests with organic coagulant was also made and dosage 2.2 L of coagulant (active part: polydiallyldimethylammoniumchloride) per 1 m3 of digestate was determined as efficient dosage for successful floc creation. Calculated energy consumption was 17.6 kWh/m3 of thickened digestate in pilot-scale, it will be lowered in the full-scale.

Short title (native language):

Aplikace nanovlákenných membrán (ENM) pro předčištění digestátu

Short summary for practitioners (native language):

Nanovlákenné membrány jsou vhodnou alternativou v současné době používaných deskových, trubkových nebo keramických membrán v oblasti separačních procesů, např. filtrace, mechanického předčištění, zahušťování, atd. Unikátní technologie výroby nanovlákenných membrán pomocí elektrospinningu produkuje membrány s otvory o velikosti až 200-400 nm, které zajišťují účinnou separaci nebo zahušťování médií. Digestát je v poslední době hojně rozšířený problematický roztok, který je třeba zpracovat před dalším použitím, např. postřikem na pole nebo využitím při kompostování. Ověřili jsme zahušťování digestátu pomocí nanovlákenných membrán. Pracovali jsme se vzorkem 8 m2 membrán, cca 500 litry digestátu a průtokem membrán mezi 2-4 LMH. Digestát byl zahuštěn z 5,8 % na 9,3 % celkové sušiny během 15 hodin provozu bez nutného zpětného proplachu membrán a přídavku koagulantů. Provedli jsme bilanci hlavních makronutrientů (C, N, P, K) v surovém digestátu, membránovém koncentrátu a membránovém permeátu. CHSK se v permeátu snížila ze 44 g/l na 9,2 g/l. Koncentrace celkového dusíku se v permeátu snížila z 5,57 na 4,16 g/l, což znamená 25% odstranění dusíku. N-NH4 se snížilo ze 4,89 g/l na 3,52 g/l, což znamená 18% odstranění N-NH4. Celkový fosfor byl v permeátu snížen z 234 mg/l na 74 mg/l, což znamená 68% odstranění TP. Koncentrace celkového draslíku byla 5,05 g/l a zůstala rozdělena stejnoměrně pro koncentrát i permeát. Byly také provedeny testy s organickým koagulantem (aktivní látka: polydiallyldimethylammoniumchlorid) a dávka pro úspěšné vytvoření vločky bylo stanovena na 2,2 l koagulantu na 1 m3 digestátu. Vypočítaná spotřeba energie byla v pilotním měřítku 17,6 kWh/m3 zahuštěného digestátu, v plném měřítku bude nižší.

Practice abstract 63

Short title (in English):

Performance of digestates as fertilizers in irrigated maize

Short summary for practitioners (in English):

Anaerobic digestion is increasingly used to treat livestock manure and produce biogas. Generally, co-substrates are added to increase the biogas production. The resulting effluent (digestate) retains most of the original nutrients present in the livestock manure and in the added co-substrates. And it can be used as a fertilizer in many arable and forage crops.
In Circular Agronomics we compare the effect, on an irrigated maize crop under Mediterranean conditions, of digestates application, from biogas production plants using dairy manure, with other common maize fertilization strategies: raw slurry and mineral fertilizers. On maize crop, digestates and slurry can be applied at pre-sowing. Mineral fertilizers can also be applied at top-dressing and achieve a highest nutrient efficiency. The proportion of ammonium N (quickly available for the crop) in digestates, respect the total N (organic and ammonium), ranges between 55 % and 60 %, slightly lower than for the pig slurry used (70-80 %).
Grain maize yield achieved when digestates are used is similar to the one achieved using slurry, both applied at pre-sowing, with equivalent N rates. The split application (pre-sowing and top-dressing) of mineral fertilizers allows a higher yield and a higher nutrient use efficiency.
Using digestates form biogas plants as fertilizer on irrigated maize is as effective and efficient as fertilization strategies using livestock manure, most common nowadays. Replacing part of the N applied with digestates by mineral fertilizers at top-dressing can contribute to improving the efficient use of this nutrient.

Short title (native language):

Comportament del digerit com a fertilitzant en blat de moro de regadiu

Short summary for practitioners (native language):

La digestió anaeròbia s’utilitza cada cop més per tractar dejeccions ramaderes i produir biogàs. Sovint, s’hi afegeixen co-substrats per tal d’incrementar la producció de gas. L’efluent (digerit) conserva la major part dels nutrients presents en les dejeccions i els co-substrats afegits i es pot utilitzar en la fertilització de molts cultius extensius.
Dins Circular Agronomics es compara l’efecte, en blat de moro en regadiu en condicions mediterrànies, de l’aplicació de digerits de plantes de producció de biogàs a partir de purins de boví, amb la d’altres estratègies de fertilització habituals: purins sense tractar i fertilitzants minerals. Digerits i purins, en blat de moro, només es poden aplicar abans de la sembra. Els fertilitzants minerals es poden aplicar també en cobertora i assolir una major eficiència d’utilització dels nutrients. La proporció de N amoniacal (disponible ràpidament pel cultiu) en el digerit, respecte el N total (orgànic i amoniacal), es situa entre el 55 % i el 60 %, lleugerament inferior a la dels purins de porcí (70-80 %).
La producció assolida pel cultiu quan s’utilitza digerit és similar a l’obtinguda amb l’aplicació de purí, ambdós en fons, aplicant dosis de N similars. Amb l’aplicació fraccionada (fons i cobertora) de fertilitzant mineral s’obté una major producció del cultiu i eficiència en la utilització dels nutrients.
Utilitzar digerits de plantes de biogàs com a fertilitzant del blat de moro en regadiu és tant eficaç i eficient com les estratègies de fertilització amb dejeccions ramaderes habituals actualment. Substituir una part del N aplicat amb els digerits amb l’aplicació de fertilitzants nitrogenats minerals en cobertora contribueix a millorar l’eficiència en la utilització d’aquest nutrient.

Practice abstract 64

Short title (in English):

Split application of manure and slurry improves performance of rainfed arable winter crops

Short summary for practitioners (in English):

The form of nutrients found in each kind of livestock manure, and their characteristics, influences the moment when they can be applied and the nutrient use efficiency by crops. Rainfed arable winter crops can be fertilized at pre-sowing (before crop sowing) and/or at top-dressing (with the crop established). Solid livestock manure, for their physical characteristics, can only be applied at pre-sowing. Liquid livestock manure (slurry, liquid fractions, digestates) can be applied both at pre-sowing and at top-dressing. The high proportion of ammonium N they contain makes their use at top-dressing more advisable.
One strategy to prioritize is using solid manure at pre-sowing and complementing this application with liquid livestock manure at top-dressing. Higher yield (400-900 kg/ha of winter cereal grain) is achieved, in respect to provide the same total N rate with a single pre-sowing solid manure application. And, more important, a higher grain protein content is also achieved, more than 0.5 perceptual points. Splitting liquid manure application among pre-sowing and top-dressing does not change winter crop yield, in respect a single pre-sowing application, but it may increase the grain protein content.
Applying all the N rate at pre-sowing increases the risk of nitrate-N leaching. Crop has low N needs in the early development stages and nitrate N is highly mobile in the soil. Splitting livestock manure application among pre-sowing and top-dressing is a good practice. It contributes to reducing N leaching losses. And a part of the N is supplied when the crop has the highest needs (between tillering and heading, in cereals) on this nutrient.

Short title (native language):

L’aplicació fraccionada de fems i purins millora el rendiment i la qualitat dels cultius extensius d’hivern en secà

Short summary for practitioners (native language):

La forma en la que es troben els nutrients en cada tipus de dejecció, i les seves característiques, influeix en el moment en què es poden aplicar i en l’eficiència en l’ús dels nutrients per part dels cultius. La fertilització dels cultius extensius d’hivern en secà es pot realitzar en fons (abans de la sembra) i/o en cobertora (amb el cultiu establert). Les dejeccions sòlides (fems), per la seva característica física, només es poden aportar abans de la sembra del cultiu. Les dejeccions líquides (purins, fraccions líquides, digerits) es poden aportar tant en fons com en cobertora. Però l’elevada proporció de N amoniacal que contenen fa més aconsellable prioritzar-ne la utilització en cobertora.
Una estratègia a prioritzar és utilitzar dejeccions sòlides en pre-sembra del cultiu i complementar aquesta aportació amb dejeccions líquides en cobertora. Es genera un increment de producció de gra de 400-900 kg/ha (cereal d’hivern), respecte aportar la mateixa dosi total de N amb dejeccions sòlides només en fons. I, més important, s’obté un increment del contingut en proteïna del gra de més de 0.5 punts percentuals. Fraccionar l’aplicació de dejeccions líquides entre fons i cobertora no varia la producció de gra de cereal, respecte fer tota l’aportació en un sol moment abans de sembrar el cultiu, i pot incrementar, també, el contingut en proteïna del gra.
Fraccionar les aplicacions de dejeccions entre fons i cobertora és una bona pràctica i contribueix a reduir les pèrdues de nitrogen per rentat, respecte aplicacions de tota la dosi en fons. S’aporta una part del nitrogen en el moment que el cultiu en té una elevada necessitat (entre fillolament i espigat, en els cereals); el cultiu té unes necessitats baixes de N en els primers estadis.

Practice abstract 65

Short title (in English):

Sowing catch crops after maize minimizes nitrate leaching

Short summary for practitioners (in English):

In Mediterranean irrigated areas, maize is a common crop. It achieves high yields and has high nutrient demands, especially on nitrogen (N). Frequently, when crop ends, there is a high amount of nitrate-N in the soil available to being leached with the autumn-winter rainfalls, if there is no crop (usual management nowadays) to absorb it, affecting groundwater quality.
N catch crop implementation after maize, which occupies the land up to the moment of preparing it for the next crop, is a good environmental practice to minimize N leaching and increase N use efficiency in these agricultural systems. Several crop species can be used. Generally, a fast growth and high N uptake in the earliest crop stages are appreciated. The most interesting species to develop this function in the Catalan irrigated agricultural systems can be: forage rapeseed, Italian ryegrass, black oat and, to a lesser extent, white mustard, linen or phacelia. Choosing the right specie will mainly depend on when the maize crop is removed and when the catch crop can be sown. Cruciferous (rapeseed, mustard, …) and Italian ryegrass require, to be effective, earlier sowing than other species. They are generally best suited to fields where maize is harvested for fodder and its recollection is earlier than when it is harvested for grain. In the tests carried out, in general, dry matter productions between 2 and 7 t/ha and N uptake between 30 and 120 kg/ha have been measured for the different catch crop species.
It is key to minimize the cost of managing these N catch crops. They should not be neither fertilized nor irrigated, nor pests and/or diseases controlled. Affordable costs are those related with sowing and harvest, if they are used for fodder, or destruction, if incorporated into the soil.

Short title (native language):

La sembra de cultius captadors després del cultiu de blat de moro minimitza el rentat de nitrats.

Short summary for practitioners (native language):

En zones mediterrànies de regadiu, el cultiu del blat de moro és freqüent. Assoleix produccions elevades i té unes altes necessitats en nutrients, especialment en nitrogen. Sovint, al final del cultiu, en el sòl hi ha quantitats elevades de N nítric que son susceptibles de rentar-se amb les pluges de tardor-hivern, si no hi ha un cultiu que el pugui absorbir, afectant la qualitat de les masses d’aigua subterrànies.
La implantació de cultius captadors de nitrogen després del blat de moro és una bona pràctica mediambiental per minimitzar les pèrdues de N per rentat i incrementar l’eficiència en l’ús del N en aquests sistemes agraris. En general es valora una ràpida implantació i una alta extracció de N en les fases més inicials. Les espècies més interesants per desenvolupar aquesta funció en els sistemes agraris de Catalunya poden ser: la colza farratgera, el raigràs italià, la civada negra i, en menor mesura, la mostassa blanca, el lli o la facèlia. La tria d’una o altra espècie dependrà principalment del moment en què es retira el cultiu de blat de moro i es pot sembrar el cultiu captador. Les crucíferes (colza, mostassa,...) i el raigràs s’adapten millor a parcel·les on s’implanta blat de moro per farratge ja que l’aprofitament és més precoç que quan s’aprofita per gra. En els assaigs realitzats s’han mesurat produccions de matèria seca entre 2 i 7 t/ha i extraccions de N entre 30 i 120 kg/ha, pels diferents cultius captadors.
Interessa minimitzar el cost del maneig d’aquests cultius captadors de N. Cal tenir en compte que aquests cultius captadors ni es fertilitzen, ni es reguen, ni s’hi fa control de plagues i/o malalties. Els costs assumibles han de ser el de la sembra i el de collita, si s’aprofiten per farratge, o destrucció, si s’incorporen en el sòl.

Practice abstract 66

Short title (in English):

Catch crops as co-substrates for the anaerobic digestion of dairy manure

Short summary for practitioners (in English):

Biogas production through anaerobic digestion has become significant as an efficient manure treatment in the European agricultural sector since, besides the obtention of a renewable fuel, it also improves manure fertilizer quality and reduces odours, pathogens as well as greenhouse gas emissions. One of the main disadvantages of this process is the low energy content of manure that makes necessary to use high energy content co-substrates, such as energy crops, in order to optimize the process and improve the economic feasibility of biogas plants. Catch crops biomass, grown without cultivation efforts and irrigation between successive rotations of maize to reduce nitrogen leaching due to maize fertilization with digested dairy manure, has demonstrated to be a good co-substrate for the anaerobic digestion of animal manures since it notably improves the process performance because, on the one hand, manure provides buffering capacity and essential nutrients for anaerobic microorganisms, while on the other hand, the high carbon content of catch crops balances the carbon to nitrogen (C/N) ratio of the influent, thus reducing the risk of ammonia inhibition. The implementation of anaerobic co-digestion of dairy manure and ensiled catch crops is feasible since methane production is increased by 43 %, 35 % and 48 % when using catch crops such as ryegrass, forage rape or black oat, respectively, in comparison to the single anaerobic digestion of dairy manure

Short title (native language):

Cultivos captadores como co-sustratos para la digestión anaerobia de purín de vaca de leche

Short summary for practitioners (native language):

La producción de biogás mediante digestión anaerobia ha ganado relevancia como un tratamiento eficiente de los purines en el sector agrícola europeo ya que, además de la obtención de un combustible renovable, también mejora la calidad del fertilizante del purín y reduce los olores, patógenos y emisiones de gases de efecto invernadero. Una de las principales desventajas de este proceso es el bajo contenido energético del purín que hace necesario el uso de co-sustratos de alto contenido energético, como los cultivos energéticos, para optimizar el proceso y mejorar la viabilidad económica de las plantas de biogás. La biomasa de cultivos captadores, cultivados sin esfuerzos de cultivo y riego entre rotaciones sucesivas de maíz para reducir la lixiviación de nitrógeno debido a la fertilización del maíz con purín de vaca lechera digerido, ha demostrado ser un buen co-sustrato para la digestión anaerobia de purín animal ya que mejora notablemente el rendimiento del proceso porque, por un lado, el purín proporciona efecto tampón para regular el pH y nutrientes esenciales para los microorganismos anaeróbicos, mientras que, por otro lado, el alto contenido de carbono de los cultivos intermedios equilibra la relación carbono/nitrógeno (C/N) del influente, reduciendo así la riesgo de inhibición por amonio. La implementación de la co-digestión anaerobia de purín de vacuno lechero y cultivos captadores previamente ensilados es factible ya que la producción de metano aumenta en un 43%, 35% y 48% cuando se utilizan cultivos como el raigrás, la colza forrajera o la avena negra, respectivamente, en comparación con la digestión anaerobia del purín sólo.

Practice abstract 67

Short title (in English):

Ensiling as a strategy to maintain the biogas potential of catch crops throughout the year for using them as co-substrate in anaerobic digestion

Short summary for practitioners (in English):

Since catch crops are seasonally sown (autumn) and harvested (spring), it is necessary to find a storage method that guarantees the availability of this co-substrate for biogas production throughout the whole year. Silage has been proved to preserve over 90% of the energy content of crops, which ensures a good nutritional value when used as animal feed. The advantages of ensiling include its low cost, its small energy footprint, the small amount of waste produced and the fact that it is a particularly environmentally friendly method, because no chemical additives are required. However, the chemical composition of the crop or its dry matter content are important factors for a success ensilage and also for the subsequent anaerobic digestion, it might therefore be expected that methane yield is affected if previous ensilage of the substrate is carried out. Ensiling is demonstrated to be an economically viable storing method, that can act as a form of chemical pre-treatment for biogas production. Ensiling improves the biodegradability and methane yield of catch crops under anaerobic conditions. The anaerobic biodegradability of ryegrass, forage rape and black oat may increase by 10 %, 14 % and 10 %, respectively, which results in an increase of the methane yield by 40 %, 46 % and 50 %, in terms of LCH4 per tonne of waste, and 19 %, 25 % and 27 %, in terms of methane production per volatile solid added. Methane production per hectare is increased by 14 %, 36 % and 34 % for ryegrass, forage rape and black oat, respectively.

Short title (native language):

Ensilado como estrategia para mantener el potencial de biogás de un cultivo captador durante todo el año para su uso como co-sustrato en la digestión anaerobia de purines

Short summary for practitioners (native language):

Dado que los cultivos captadores se siembran estacionalmente (otoño) y se recolectan (primavera), es necesario encontrar un método de almacenamiento que garantice la disponibilidad de este co-sustrato para la producción de biogás durante todo el año. Se ha demostrado que el ensilado conserva más del 90% del contenido energético de los cultivos, lo que garantiza un buen valor nutricional cuando se utiliza como pienso. Entre las ventajas del ensilado se encuentran su bajo coste, su pequeña huella energética, la pequeña cantidad de residuos producidos y el hecho de que es un método especialmente respetuoso con el medio ambiente, ya que no se requieren aditivos químicos. Sin embargo, la composición química del cultivo o su contenido de materia seca son factores importantes para un ensilaje exitoso y también para la posterior digestión anaerobia, por lo que podría esperarse que el rendimiento de metano se vea afectado si se realiza un ensilaje previo del sustrato. Se ha demostrado que el ensilado es un método de almacenamiento económicamente viable, que puede actuar como una forma de pretratamiento químico para la producción de biogás. El ensilado mejora la biodegradabilidad y el rendimiento de metano de los cultivos intermedios en condiciones anaerobias. La biodegradabilidad anaerobia del raigrás, la colza forrajera y la avena negra puede aumentar en un 10%, 14% y 10%, respectivamente, lo que resulta en un aumento del rendimiento de metano en un 40%, 46% y 50%, en términos de LCH4 por tonelada de residuo, y 19%, 25% y 27%, en términos de producción de metano por sólido volátil añadido al digestor. La producción de metano por hectárea se incrementa en un 14%, 36% y 34% para el raigrás, la colza forrajera y la avena negra, respectivamente.

Practice abstract 68

Short title (in English):

Technical and economical evaluations for acid whey pretreatment

Short summary for practitioners (in English):

The activity creates new business potential of valorisation food waste via its processing into agricultural field. Acid whey, i.e. waste product from cottage cheese and cream cheese production is processed by acid whey storage tank then microfiltration, centrifuge for fat removal and, if necessary, acid whey thickening to ca. 16 - 18 % TSS for further use (e.g. animal fodder preparation). Farmers could use acid whey to enrich their soil not only by carbon, but also by nutrients (nitrogen, phosphorus and potassium). It can create win-win scenario between dairy industry producers and farmers to create market with this commodity. Our innovation includes application of electrospun nanofibrous membranes instead of centrifuge for fat removal from acid whey. Electrospun nanofibrous membranes are proper alternative of recently used flat-sheet, tubular or ceramic membranes in the area of separation processes, e.g. filtration, mechanical pre-treatment, thickening, etc. Unique technology of electrospinning production produces nanofibrous membranes with holes up to 200 – 400 nanometers to ensure efficient separation. Our study was triggered by overall acid whey management evaluation at real full-scale plant and pilot-tests were carried out to compare efficiency of fat removal from acid whey at full-scale (centrifuge) and pilot-scale (nanofibrous membranes - NM). NM showed comparable separation of fats as centrifuge and produced clear permeate in comparison with turbid centrate from centrifuge. Turbidity was thoroughly analyzed and it is caused by calcium and magnesium phosphate and/or calcium lactate. NM showed competitive operational and investment costs to centrifuge at pilot-scale.

Short title (native language):

Technologické a ekonomické vyhodnocení předčištění kyselé syrovátky

Short summary for practitioners (native language):

Naše aktivita vytváří nový podnikatelský potenciál zhodnocování potravinového odpadu jeho zpracováním na zemědělské pole. Kyselá syrovátka, tj. odpadní produkt z výroby tvarohu a smetanových sýrů, se zpracovává v zásobníku na kyselou syrovátku, následně mikrofiltrací, odstředěním pro odstranění tuku, a v případě potřeby zahuštěním kyselé syrovátky na cca 16-18 % sušiny pro další využití (např. příprava krmiva pro zvířata). Zemědělci by mohli používat kyselou syrovátku k obohacení půdy nejen o uhlík, ale také o živiny (dusík, fosfor a draslík). Může tak vzniknout oboustranně výhodný scénář mezi výrobci mléka a zemědělci, kteří by s touto komoditou vytvořili trh. Naše inovace zahrnuje použití nanovlákenných membrán (NM) namísto odstředivky pro odstranění tuku z kyselé syrovátky. NM jsou vhodnou alternativou v současné době používaných plochých, trubkových nebo keramických membrán v oblasti separačních procesů, např. filtrace, mechanického předčištění, zahušťování, atd. Unikátní technologie výroby elektrospinningem produkuje nanovlákenné membrány s otvory o velikosti až 200-400 nanometrů, které zajišťují účinnou separaci. Naše studie začala celkovým auditem hospodaření s kyselou syrovátkou v reálném provoze a byly provedeny pilotní testy k porovnání účinnosti odstraňování tuku z kyselé syrovátky v reálném provoze (odstředivka) a v pilotním měřítku (NM). NM vykazovaly srovnatelné odstranění tuků jako odstředivka a produkovaly čirý permeát ve srovnání se zakaleným fugátem z odstředivky. Zákal byl důkladně analyzován a je způsoben fosforečnanem vápenatým a hořečnatým a/nebo mléčnanem vápenatým. NM vykázala v pilotním měřítku konkurenceschopné provozní a investiční náklady oproti odstředivce.

Practice abstract 69

Short title (in English):

Reaping multiple benefits of Climate Smart Agriculture: The case of dairy farmers in East Africa

Short summary for practitioners (in English):

Eastern Africa farmers are not producing enough to feed themselves and trade the surplus due to many challenges: low input/technologies use and limited economic support services. The problem is intensified by African agriculture’s extreme vulnerability to climate change. With the effects of climate change already being felt, many projects are seeking solutions. Climate-smart agriculture (CSA) is among integrated approaches that have proven to address the interlinked challenges of food security and accelerating climate change. Several organizations have done a significant amount of work in CSA. The major challenge is that this work has not been effectively disseminated to farmers in Africa. Eastern Africa Farmers Federation is currently scaling up CSA approaches such us: nutrient management, integrated livestock management and soil and water conservation to help farmers achieve the triple win of CSA: increasing productivity, enhance resilience and reduced emissions. Specifically, in the dairy sector, after strengthening the capacity of farmer on CSA and advocacy campaigns pushing for supportive policies for CSA; incoming data shows that among 12,548 farmers of which 60% adopted various CSA, demonstrated that the uptake of fodder shrubs and herbaceous legumes into mixed farming systems increase dairy productivity by 50 – 100%, improve food security and eventually reduced emissions through zero-grazing that improved manure management. Installation of biogas units in some farms allowed rural households to generate alternative energy thus reaping multiple benefits of CSA. We call on governments to support multistakeholder partnerships that will have business-incentive approach to achieve sustainability and scale.

Short title (native language):

Récolter de multiples avantages de l'agriculture intelligente face au climat : le cas des producteurs laitiers en Afrique de l'Est

Short summary for practitioners (native language):

Les agriculteurs d'Afrique de l'Est ne produisent pas assez pour se nourrir et commercialiser l'excédent en raison de nombreux défis : faible utilisation des intrants et services économiques limités. Le problème est aggravé par l'extrême vulnérabilité au changement climatique. D'après cela de nombreux projets cherchent des solutions. L'agriculture intelligente face au climat AIC fait partie des approches intégrées utilise pour relever les défis interdépendants de la sécurité alimentaire et de l'accélération du changement climatique. Plusieurs organisations ont réalisé un travail considérable. Le défi majeur est que ce travail n'a pas été diffusé aux agriculteurs en Afrique. EAFF étend actuellement les approches de la AIC telles que la gestion des nutriments, la gestion intégrée de l'élevage, la conservation des sols et de l'eau pour aider les agriculteurs à atteindre le triple gain de la AIC : augmenter la productivité, améliorer la résilience et réduire les émissions. Précisément, dans le secteur laitier, après le renforcement des capacités des agriculteurs sur l'AIC et le plaidoyer en faveur de politiques de soutien ; les données montrent que parmi 12 548 agriculteurs, dont 60% ont adopté diverses CSA, ont démontré que l'absorption d'arbustes fourragers et de légumineuses herbacées dans les systèmes d'agriculture mixte augmente la productivité laitière de 50 à 100%, améliore la sécurité alimentaire et finalement réduit les émissions grâce au zéro-pâturage. L'installation d'unités de biogaz dans certaines fermes a permis aux ménages ruraux de générer une énergie alternative, tirant ainsi de multiples avantages de l'AIC.Nous appelons aux gouvernements à soutenir les partenariats pour atteindre la durabilité et l'échelle.

Practice abstract 70

Short title (in English):

What is the right time to fertilize silage maize with slurry or biogas digestate?

Short summary for practitioners (in English):

Slurry from animals like cattle or pigs contain nitrogen in the form of ammonia and organically bound, usually in almost equal shares. Biogas digestate has similar characteristics. Before plants can take up nitrogen it has to be converted from ammonia to nitrate which may take 1 to 4 weeks depending on the weather and soil conditions. Organically bound nitrogen (fixed in carbon-containing particles) need to be mineralized first, in order to become plant available. Only a small share of organically fixed nitrogen will be mineralized within one growing season. An early slurry or digestate application may lead to a long time available for mineralization and therefore to higher shares of plant available nitrogen. On the opposite, nitrate in the soil is prone to leaching. The longer the timespan between fertilization and plant uptake, the higher is the risk of loss of nitrate into ground water bodies. Because liquid organic fertilizers require large storage capacity, farmers may need to empty storage tanks as soon as possible after winter. This may be 2 to 3 months before planting, and 4 to 5 months before the main nitrogen demand. An application close to the time of demand (plants have developed and reached a certain height), may be too late because dry weather may restrict growth. In areas with good water supply, fertilization should be more close to the time of nitrogen demand while in dry areas, application can be made more early because the risk of leaching is much smaller and as more time the slurry spends in the soil, the more organic nitrogen mineralizes.

Short title (native language):

Wann sollte Silomais mit Gülle oder Gärrest gedüngt werden?

Short summary for practitioners (native language):

Flüssige Wirtschaftsdünger enthalten Stickstoff organisch gebunden und in Form von Ammonium. Vor der Stickstoff-Aufnahme durch Pflanzen muss das enthaltende Ammonium im Boden zu Nitrat umgewandelt werden. Dies kann je nach Witterung bis zu vier Wochen dauern. Organisch gebundener Stickstoff muss zunächst mineralisiert werden, bevor er pflanzenverfügbar wird. Nur ein kleiner Teil des organisch gebundenen Stickstoffs mineralisiert gewöhnlich im Anwendungsjahr. Eine frühe Gülle- oder Gärrestausbringung ermöglicht einen längeren Zeitraum der Mineralisierung und damit potenziell eine größere Ausnutzung des enthaltenden Stickstoffs. Andererseits ist Nitrat im Boden auswaschungsgefährdet. Je mehr Zeit zwischen der Ausbringung und der Aufnahme durch die Pflanze vergeht, desto höher ist das Risiko von Stickstoffverlusten ins Grundwasser. Wegen begrenzter Lagerkapazitäten sind Landwirte häufig bestrebt, Gülle nach dem Winter zum frühesten Zeitpunkt auszubringen. Zwischen der Ausbringung und der Aussaat können so schon zwei bis drei Monate vergehen. Bis zum Zeitpunkt der hauptsächlichen Stickstoffaufnahme können immerhin vier bis fünf Monate vergehen. Eine Ausbringung zu kurz vor dem Zeitpunkt der hauptsächlichen Nährstoffaufnahme kann witterungsbedingt (Trockenheit) zu verringerter Stickstoffaufnahme führen. In Regionen guter Wasserversorgung sollte die Ausbringung näher am Zeitpunkt der Nährstoffaufnahme liegen, während in trockenen Regionen eine frühe Düngung früh erfolgen kann. Die Gefahr der Auswaschung ist dort reduziert und eine verlängerte Mineralisierungszeit kann zu besserer Nährstofffreisetzung führen.

Further details

Links to other website(s):

IRTA website

RISE website

Audiovisual material:

Dissemination materials

Video Site 1_Catalonia_Precision Feeding

Description of the context of the project:

It is estimated that around 13.6 Mt of N and 1.8 Mt of P enter the EU agricultural system annually in the form of mineral fertilisers and feed. Nevertheless, nutrient use through the whole European agri-food chain is still inefficient: for every five tons of N entering the EU agri-food chain, only one ton is converted to finished products for human consumption. These low efficiencies result in large loss of nutrients into the environment with negative impacts on soils, water and air, and constitute unacceptable health and environmental costs: around 15% of EU land exhibits a surplus in excess of 40 kg N ha‐1. Excess nitrogen in the soil from high fertiliser application rates and/or low plant uptake can cause an increase in mineralisation of organic carbon, which, in turn, leads to an increased loss of carbon from soils. Around 45% of the mineral soils in Europe have low or very low organic carbon content (0–2%). Low levels are particularly evident in the southern countries of Europe but also in some parts of more northern countries such as France, Germany and Belgium, with predicted future losses of up to 24 % of current stocks due to climate change . Low soil carbon storage is linked with negative environmental and societal impacts, whereas soil C sequestration is projected to improve a suite of environmental social services, including soil and water quality, biodiversity and food security, whilst simultaneously reducing the social, economic and environmental threats of climate change . A relevant mechanism to increase soil C is the transformation of waste products into organic amendments for application on soils, improving OC flow connectivity in the agricultural sector.