PROJECT DESCRIPTION
BACKGROUND
Since the implementation of the 91/27³/EEC Directive on Urban Waste Water Treatment, the amount of sludge generated in the EU has increased dramatically. This trend is expected to continue, with sludge output rising from 7 million tonnes/yr to 20 million tonnes/yr in the next decade. The general principles for the management of sewage sludge are stated in many national and European laws. These principles are based on the privileging, as far as possible, of actions of treatment, valorisation and recovery of the matter. Furthermore, these should not present a threat to human health or the environment. This is in line with sustainable development policy. Current processes of elimination or treatment of the sewage sludge – which include incineration, burial and spreading - are no longer adequate to deal with its constantly increasing volume.
OBJECTIVES
Research into matter cycles and matter re-use needs to develop a new, environmentally friendly industrial process of elimination, treatment and valorisation of sewage sludge. To this end, FINAXO has developed a new process for heat treatment and energy recovery of organic waste by pyrogasification - Pyrobio. This LIFE project aims to develop the patented Pyrobio process at an industrial scale. It seeks to build on laboratory work and previous tests with the residual liquors resulting from the distillation of beets to demonstrate its adaptability and transferability to other organic waste - sewage sludge. The project hopes to show that the Pyrobio system fulfils the requirements of sustainable development and integrated management of resources. Part of this will be the re-use of gas produced from the heating process as energy in a closed circuit.
The main objectives of the project are:
Finally, the project will work to increase the awareness of citizens on the treatment and valorisation of sludge from WWTP so that there is better acceptance of these plants. Similarly, work will be undertaken with WWTP managers to increase their knowledge of this new process.
RESULTS
The Pyrobio project contributed successfully to the development and demonstration of an innovative high temperature pyrolysis technology for sludge treatment with significantly higher energy and environmental performances than incineration and pyrolysis at low temperature. Several improvements were brought to the technology during the project. Series of tests defined in a protocol were carried out and the measurements regarding environmental performance of the pilot were made by dedicated COFRAC accredited laboratory (quality of the gas and ashes, energy performance). As a result, in terms of energy, the Pyrobio pilot produced more energy that it consumed. The project objectives were exceeded: the treatment cost for elimination/valorisation of sludge is reduced by about 60% compared to 20% foreseen (including the drying of the sludge); the quantity of residual waste is decreased by more than 20% as foreseen; the pilot is not only self-sufficient in energy as foreseen but produces 360 KW of surplus after sludge drying. The only objective that has not been met is the reduction of the CO2 emissions, which were reduced by 33% compared to 100% foreseen. This technology is adaptable to other types of waste with interesting energy performances (tyres/plastic, wood, vegetable of fruit wastes), and to different scale and treatment capacity (larger units). It is easy to build, use and maintain and it allows the treatment of waste on-site. The local authorities and the industry showed a real interest in this technology during the project that has been widely advertised from local to international scale through dissemination tools and events, as well as training sessions and visits on the pilot site. Projects of installation of Pyrobio technology are in progress in Italy, Canada and Poland. The Pyrobio project contributed successfully to the development and demonstration of an innovative high temperature pyrolysis technology for sludge treatment with significantly higher energy and environmental performances than incineration and pyrolysis at low temperature. Several improvements were brought to the technology during the project. Series of tests defined in a protocol were carried out and the measurements regarding environmental performance of the pilot were made by dedicated COFRAC accredited laboratory (quality of the gas and ashes, energy performance). As a result, in terms of energy, the Pyrobio pilot produced more energy that it consumed. The project objectives were exceeded: the treatment cost for elimination/valorisation of sludge is reduced by about 60% compared to 20% foreseen (including the drying of the sludge); the quantity of residual waste is decreased by more than 20% as foreseen; the pilot is not only self-sufficient in energy as foreseen but produces 360 KW of surplus after sludge drying. The only objective that has not been met is the reduction of the CO2 emissions, which were reduced by 33% compared to 100% foreseen. This technology is adaptable to other types of waste with interesting energy performances (tyres/plastic, wood, vegetable of fruit wastes), and to different scale and treatment capacity (larger units). It is easy to build, use and maintain and it allows the treatment of waste on-site. The local authorities and the industry showed a real interest in this technology during the project that has been widely advertised from local to international scale through dissemination tools and events, as well as training sessions and visits on the pilot site. Projects of installation of Pyrobio technology are in progress in Italy, Canada and Poland.
