Microbial methanation of H2/CO2 in thermophilic anaerobic trickle bed reactors by a mixed microbial biocenosis
With changing energy policy towards utilization of renewable resources,the development of compatible energy conversion and storage technologies becomes increasingly important.Microbial methanation of CO2 emissions with H2 can become a suitable conversion and storage technology using the capacity of the existing gas grid.In contrast to limitations with other concepts,increased methane production rates are expected in anaerobic trickle bed reactors,due to the enhanced gasliquid mass transfer.Still,this technology has been investigated only in a few studies under mesophilic conditions.The current study reports on long-term operation of a thermophilic (55℃) anaerobic trickle bed reactor (58 L) at atmospheric pressure.Reactor start-up,the development of a methanogenic biocenosis from a mesophilic wastewater treatment plant (WWTP) sludge digester,methane generation and effluent gas quality as well as nutrient supply strategies were investigated.During long-term operation,a methane production rate of up to 15.4 m3CH4 / (m3·d) was achieved with corresponding methane concentrations above 96%.This exceeds methane production rates reported with other mesophilic or thermophilic reactor setups operated at atmospheric pressure,illustrating the high potential of thermophilic anaerobic trickle bed reactors as a very efficient energy conversion and storage technology.Molecular biological analyses showed a clear shift from the mesophilic inoculum to a thermophilic biocenosis,and the active methanogenic fraction was dominated by Methanothermobacter spp.Establishing an anaerobic biofilm under thermophilic conditions required an extended start-up period.Control ofpH as well as availability of sufficient trace element and macro nutrient supply turned out to be crucial for stable reactor operation.The replacement of the artificial macro nutrient solution with centrifuged digestate supematant revealed a high potential for scale-up of this technology,but could not replace trace element supply.
Biomethanation hydrogenotrophic archaea nutrient supply thermophilic anaerobic biofilm
Dietmar Strübing Bettina Huber Michael Lebuhn J(o)rg E.Drewes Konrad Koch
Technical University of Munich, Chair of Urban Water Systems Engineering, Am Coulombwall 3, D-85748 Bavarian State Research Center for Agriculture, Central Department for Quality Assurance and Analyti
国际会议
The 15th IWA World Conference on Anaerobic Digestion( 第15届IWA世界厌氧大会)
北京
英文
336-339
2017-10-17（万方平台首次上网日期，不代表论文的发表时间）