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Innovative wastewater treatment promises energy recovery  

02/04/2013

The BioFatRecovery project addresses a sticky problem: treatment of wastewater that contains fat, for example from dairy or meat processing. Project partner Ambisys has developed the Inverted Anaerobic Sludge Blanket (IASB) reactor, which makes it possible to efficiently remove fat from wastewater and convert it into useful bioenergy in the form of biogas. The treatment process is ideal for small-scale facilities and is a good example of a project that targets SMEs. Through BioFatRecovery, an IASB reactor is being installed and tested at a fish processing plant in Póvoa de Varzim, northern Portugal.

Merijn Picavet, Ambisys chief technology officer, explains how the IASB works, the benefits it could offer, and how it could be exported worldwide to reduce the environmental impacts of wastewater containing fat. 

Can you summarise what the IASB is and does? 

Merijn Picavet: Ambisys provides a sustainable solution for the treatment of wastewater and organic waste. The solution includes the possibility for users to recover energy from their waste or effluence. To be able to do that, and to be more competitive, we develop our own technologies and that is where the eco-innovation kicks in. Ambisys is a spin-off of the University of Minho, Braga, Portugal, and our solutions are developed together with the university. 

One of our technologies is based on the fundamental research that was performed at the university. Through that fundamental research we were able to come up with a technical solution to a problem that had not been resolved up to that point: treatment of industrial wastewater containing fat. 

Fat is normally a problem for biological wastewater treatment systems, as conventional treatment systems cannot deal with it. Fat induces flotation and most conventional treatment systems are based on sedimentation. You could think of membrane systems, but fat clogs membrane systems. So what you normally do is remove fat before any biological treatment. 

Our IASB reactor retains anaerobic sludge inside the reactor through floatation and sedimentation. Since fat is normally lighter than water and attaches to sludge, retention through floatation makes it possible to treat wastewater containing fat and convert it into biogas. 

We focused on anaerobic treatment systems because fat is very interesting as a substrate for biogas production. You can produce much more biogas from fat than from, for example, sugars or proteins, and that makes it very interesting for industry. For example, the food industry normally produces wastewater containing fat - think of dairy, meat processing, fish processing. They all have wastewater containing fat and on top of that they are quite energy intensive because they use a lot of steam for sterilisation purposes. They consume a lot of fuel. This treatment gives them an opportunity to recover even more biogas than before, and to use it to produce steam. 

On top of that, our technology is modular. That means that we created a technology that can be applied to any size of reactor, making it easy to scale up. And we do not include any mechanical parts inside our reactor. There are technologies available that are capable of dealing with fat, but they have technical components inside the reactor to remove the fat, to scrape it off, for example. We don't do that. We use the fat to retain the biomass inside our reactors, and give the biomass an opportunity to degrade the fat and organic compounds and produce biogas. 

How is the BioFatRecovery project developing the innovation? 

Merijn Picavet: We are installing our first reference at a fish processing plant in northern Portugal. The IASB has been recognised by the European Commission as a technology with potential that was worthwhile investing in. 

We decided to address the market specifically of small and medium-sized enterprises (SMEs) for now with a solution that is affordable. We mean it to be affordable because most other treatment systems are not that affordable for SMEs such as cheese producers or small slaughterhouses. We are installing it at an SME that produces canned sardines. 

What environmental benefits do you expect and how will you bring the reactor to a wider market? 

Merijn Picavet: We have done the calculation of expected benefits but we have to actually show that it is like that. Basically, we can recover the organic pollutants in the form of biogas, and so we are actually reducing emissions, because normally this fish processing plant would discharge the waste product to a sewer and it would go directly to a normal wastewater treatment plant, which implies oxygen consumption and all the carbon dioxide emissions associated with that. We recover the pollutants as biogas and we can substitute part of the fossil fuel that food processing plants consume. In the case of the fish processing plant in Póvoa de Varzim, that is propane gas. If everything goes according to plan they might be able to substitute 30% of their propane consumption.

We are currently putting the IASB reactor on the market. In five years' time we should have installed several reactors and should be able to offer the reactor at several sizes and have continued to develop the product. The first reference will be in Portugal [at the Póvoa de Varzim fish plant], and lucky for us it's close to our headquarters, but we're focusing on the European market and the South American and Asian markets. Through our main shareholder, the MonteAdriano Group, we have privileged access to the African market as well, in particular Mozambique and Angola.

BioFatRecovery

Duration: November 2011-October 2014

Co-funded by the CIP Eco-Innovation Programme (50% contribution to project budget of €786,809)

Project website: http://www.biofatrecovery.eu/ français