Anaerobic granule-based biofilms formation reduces propionate accumulation under high H2 partial pressure using conductive carbon felt particles.
Syngas based co-digestion is not only more economically attractive than separate syngas methanation but also able to upgrade biogas and increase overall CH4 amount simultaneously. However, high H2 concentration in the syngas could inhibit syntrophic degradation of propionate, resulting in propionate accumulation and even failure of the co-digestion system. In an attempt to reduce propionate accumulation via enhancing both H2 interspecies transfer (HIT) and direct interspecies electron transfer (DIET) pathways, layered granule-based biofilms induced by conductive carbon felt particles (CCFP) was employed. The results showed that propionate accumulation was effectively reduced with influent COD load up to 7gL(-1)d(-1). Two types of granule-based biofilms, namely biofilm adhered to CCFP (B-CCFP) and granules formed by self-immobilization (B-SI) were formed in the reactor. Clostridium, Syntrophobacter, Methanospirillum were possibly involved in HIT and Clostridium, Geobacter, Anaerolineaceae, Methanosaeta in DIET, both of which might be responsible for the high-rate propionate degradation.
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Heng
H
Xu
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Cuiping
C
Wang
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Kun
K
Yan
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Jing
J
Wu
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Jiane
J
Zuo
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China. Electronic address: wkj@mail.tsinghua.edu.cn.
Kaijun
K
Wang
D000693:Anaerobiosis; D018441:Biofilms; D056804:Biofuels; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology; D001709:Biotechnology / Q000295:instrumentation / Q000379:methods*; D002244:Carbon; D000077482:Carbon Fiber; D003013:Clostridium / Q000378:metabolism; D004579:Electron Transport; D045302:Geobacter / Q000378:metabolism; D006859:Hydrogen; D008697:Methane / Q000378:metabolism; D059013:Microbial Consortia; D010313:Partial Pressure; D011422:Propionates / Q000378:metabolism*
D056804:Biofuels; D000077482:Carbon Fiber; D011422:Propionates; D002244:Carbon; D006859:Hydrogen; D008697:Methane
Co-digestion; Direct interspecies electron transfer (DIET); Granule-based biofilms; H(2) interspecies transfer (HIT); Propionate accumulation; Syngas