Hydrogen concentration as a possible control parameter for biogas plants Thomas Kirner, Ellen Euchner, Bettina Manns, Thomas Frank, Marcus Kiuntke, Dieter Bryniok Projektförderung Figure 1: Diagram of the anaerobic digestion Figure 2: Experimental setup with 2L-bioreactors Figure 3: Experimental setup with 8 L-bioreactor 272 284 296 308 320 332 350 362 368 374 380 389 398 407 416 425 434 440 446 452 461 470 479 488 497 506 509 512 527 536 545 554 563 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 0,0 200,0 400,0 600,0 800,0 1.000,0 1.200,0 1.400,0 0 10 20 30 40 50 60 70 FOS/TAC Konzentration / [mg/L] Versuchsdauer [d] Stärke: Fermenter R1 Essigsäure / [mg/L] Propionsäure / [mg/L] Isobuttersäure / [mg/L] Buttersäure / [mg/L] Isovaleriansäure / [mg/L] Valeriansäure / [mg/L] Hexansäure / [mg/L] Ameisensäure / [mg/L] FOS/TAC-Wert Treshold H 2 partial pressure Acetoklastic methanogenesis > 10 Pa Hydrogenotrophic methanogenesis < 10 Pa Homo-acetogenesis 52 – 95 Pa Propionat oxidation > 10 Pa Butyrat oxidation > 100 Pa Ethanol and lactat oxidation 10 5 Pa Figure 4:Methan production withe different substrates, in 2 l reactors Figure 5: Fatty acids with starch as substrate in a 2 l reactor Figure 6: Fatty acids and specific rotation with albumin and celluse as substrate In the 8 l reactor. Specific rotation has been detected with a polarimeter from CiS Forschungsinstitut für Mikrosensorik GmbH, Erfurt. Figure 7: Fatty acids, hydrogen and hydrogen sulfide with albumin and celluse as substrate In the 8 l reactor. Hydrogen and hydrogen sulfide were detected with a sensor system from BlueSens gas sensor GmbH