Energy Recovery from Sludge Gases at a Municipal Sewage Treatment Plant
In Brazil, anaerobic processes are frequently used, either as one of the stages or sometimes as the only stage, for wastewater treatment. The resulting climate-damaging sludge gases are either burned off or discharged into the atmosphere without being either harnessed or treated. On the other hand, alternative fuels, such as bioethanol, are in widespread use in the transport sector. Hence, the majority of newly registered vehicles are equipped with flex-fuel engines and are capable of switching between petrol, ethanol and natural gas.
The purpose of the project is to capture the sludge gases from Carioba sewage treatment plant in Americana, upgrade them to natural-gas quality and make them available to the public vehicle fleet as biofuel (biomethane). The services to be rendered within the project will include process selection, siting, compilation of basic data and detail engineering, construction and commissioning of the plant as well as an aftercare phase. In addition, some of the vehicles in the municipal fleet will be converted to run on biomethane, and there will be accompanying training measures.
Both the reduction in methane emissions and also the substitution of fossil fuels with biomethane will result in a lowering of greenhouse gas emissions. In view of the currently proceeding expansion of sewage treatment in Brazil, the project is likely to exert a strong beacon effect on imitator projects. German technology will be transferred to Brazil via licensees.
Target country: Brazil
Implementation: Fraunhofer Institute for Interfacial Engineering and Biotechnology, Stuttgart
Partners in the target country: City of Americana;
Municipal water and sanitation utility (DAE)
Overall project funding (incl. BMU grant): € 1,930,000
Duration: 02/2009 to 06/2011