Mulhouse region’s SIVOM (Multipurpose Intercommunal Syndicate) and SUEZ have inaugurated a methanization unit. Located in the heart of the Sausheim (East of France) ecohub, the facility will make it possible to recover 100% of sludge from the wastewater treatment plant to produce 2,000,000 Nm3 of purified biomethane each year, equivalent to the consumption of 125 urban transport buses in the Mulhouse agglomeration.
This green gas will supply 44 buses of the Mulhouse agglomeration by 2022, compared with 22 today. For the moment, the biomethane not consumed by the buses is intended for the buildings of the Mulhouse Alsace Agglomeration. The entire bus fleet will run on biomethane by 2034.
The facility fully meets the agglomeration’s energy transition needs by reinforcing the energy complementarity between the wastewater treatment plant and the energy-from-waste plant. Indeed, the methanization unit recovers in green energy 100% of sewage sludge by using the waste heat produced by the energy-from-waste plant to maintain the two methanization tanks at constant temperature (37°C). The digested sludge recovered from the anaerobic digester is centrifuged and its solid residue is treated within the energy-from-waste plant.
This process complements the ecohub’s existing energy markets, namely electricity production for the self-consumption of the two sites, steam production for the “Papèteries du Rhin” paper mills, and supply of the hot water network for municipality heating.
“The completion of this project is a major element in the energy transition policy implemented throughout the Greater Mulhouse agglomeration. The entire Sausheim site, which includes the energy-from-waste plant and the wastewater treatment plant, is progressively evolving to become a major actor in the circular economy and renewable energy production, by mixing production of electricity, steam, gas and fertilizer,” said Francis Hillmeyer, President of Mulhouse region’s SIVOM.
“The Sausheim methanization unit illustrates SUEZ’s capacity for innovation and its commitment to its customers. By creating local circular economy loops from wastewater and waste, and by recovering phosphorus, SUEZ is providing the best support to local communities in their energy transition,” added Maximilien Pellegrini , Deputy CEO of SUEZ – France Region.