Logroño Washington, Popp Denny, Nikolausz Marcell, Kluge Paul, Harms Hauke, Kleinsteuber Sabine
Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany.
Front Microbiol. 2021 Feb 11;12:619632. doi: 10.3389/fmicb.2021.619632. eCollection 2021.
biomethanation allows the conversion of hydrogen produced from surplus electricity to methane. The flexibility of the process was recently demonstrated, yet it is unknown how intermittent hydrogen feeding impacts the functionality of the microbial communities. We investigated the effect of starvation events on the hydrogen consumption and methane production rates (MPRs) of two different methanogenic communities that were fed with hydrogen and carbon dioxide. Both communities showed functional resilience in terms of hydrogen consumption and MPRs upon starvation periods of up to 14 days. The origin of the inoculum, community structure and dominant methanogens were decisive for high gas conversion rates. Thus, pre-screening a well performing inoculum is essential to ensure the efficiency of biomethanation systems operating under flexible gas feeding regimes. Our results suggest that the type of the predominant hydrogenotrophic methanogen (here: ) is important for an efficient process. We also show that flexible biomethanation of hydrogen and carbon dioxide with complex microbiota is possible while avoiding the accumulation of acetate, which is relevant for practical implementation. In our study, the inoculum from an upflow anaerobic sludge blanket reactor treating wastewater from paper industry performed better compared to the inoculum from a plug flow reactor treating cow manure and corn silage. Therefore, the implementation of the power-to-gas concept in wastewater treatment plants of the paper industry, where biocatalytic biomass is readily available, may be a viable option to reduce the carbon footprint of the paper industry.
生物甲烷化可将多余电力产生的氢气转化为甲烷。该过程的灵活性最近得到了证明，但间歇性氢气进料如何影响微生物群落的功能尚不清楚。我们研究了饥饿事件对以氢气和二氧化碳为原料的两种不同产甲烷群落的氢气消耗和甲烷产生速率（MPR）的影响。在长达14天的饥饿期内，两个群落的氢气消耗和MPR均表现出功能恢复力。接种物的来源、群落结构和优势产甲烷菌对高气转化率起决定性作用。因此，预先筛选性能良好的接种物对于确保在灵活气体进料方式下运行的生物甲烷化系统的效率至关重要。我们的结果表明，主要的氢营养型产甲烷菌（此处： ）的类型对高效过程很重要。我们还表明，利用复杂微生物群对氢气和二氧化碳进行灵活的生物甲烷化是可能的，同时避免了乙酸盐的积累，这对于实际应用很重要。在我们的研究中，来自处理造纸工业废水的上流式厌氧污泥床反应器的接种物比来自处理牛粪和玉米青贮饲料的推流式反应器的接种物表现更好。因此，在造纸工业废水处理厂中实施电力-气体概念，因为那里生物催化生物质很容易获得，可能是减少造纸工业碳足迹的可行选择。
