Zweistufige Druckfermentation - ein innovatives, optimiertes Verfahren für die Erzeugung von Biogas zur Netzeinspeisung (Two-stage pressure fermentation – optimising biogas production for injection into a natural gas grid)
- Publikations-Art
- Zeitschriftenbeitrag
- Autoren
- Wonneberger, A.-M.; Lemmer, A.; Graf, F.; Reimert, R.
- Erscheinungsjahr
- 2011
- Veröffentlicht in
- GWF, Gas - Erdgas
- Band/Volume
- 152/6
- ISBN / ISSN / eISSN
- 00164909
- Seite (von - bis)
- 370-377
The DVGW research centre at the Engler-Bunte-Institute of the Karlsruhe Institute of Technology and the State Institute of Agricultural Engineering and Bioenergy at the University of Hohenheim develop jointly a two-stage pressure fermentation process. By this process biogas will be produced, upgraded and injected in the natural gas grid more efficiently. The development is funded by the German Ministry of Education and Research (BMBF) in the joint research project "B2G-innovative production of gaseous fuels from biomass". In the new process biomass is percolated and the degradable part is thereby converted into a fluid. The resulting fermentation broth is subsequently fermented under elevated pressure in a fixed bed reactor to produce biogas. Compared to conventional biogas production twostage fermentation allows shorter retention times and thereby higher organic loading rates. Because of low pH-values and increased temperatures even persistent substrates can be solubilised and hence the substrate spectrum is broadened. As a by-product a hydrogen rich gas is produced, which can be used in a CHP, e.g. applying a fuel cell. The fermentation in the second reactor produces a pressurized biogas (> 5 bar). Due to the high solubility of carbon dioxide in the fermentation broth the biogas has an increased methane content which can exceed 90 mol-%. This will reduce both the capex and the opex for the upgrading plant. In addition, the elevated pressure reduces the energy demand for gas upgrading by 6-14 % because no compression is needed in order to inject the gas into the gas grid.