Direct methanation and storage concepts for the flexibilization of biogas plants

The enrichment of methane fraction in the biogas mixture is an innovative possibility to make existing biogas plants more flexible by using excess power. In the described concept the CO2 in the biogas is directly catalytically converted into CH4 with H2. The CH4 enriched biogas is again fed into the digester to save energy for a later use in the CHP. Additionally the fed heat gas can mix and heat the substrate. Therefore, a heat pipe injector system was developed for cooling the hot biogas stream after methanation and to prevent damages of the microbial consortia during the biomass mixing. The concept is proved at a laboratory biogas plant.