Reducing CO_(2) to produce methane through microbial electrolytic cell(MEC)is one of the important methods of CO_(2) resource utilization.In view of the problem of low methanogenesis rate and weak CO_(2) conversion ra...Reducing CO_(2) to produce methane through microbial electrolytic cell(MEC)is one of the important methods of CO_(2) resource utilization.In view of the problem of low methanogenesis rate and weak CO_(2) conversion rate in the reduction process,theflowfield environment of the cathode chamber is changed by changing the upper gas cir-culation rate and the lower liquid circulation rate of the cathode chamber to explore the impact on the reactor startup and operation and products.The results showed that under certain conditions,the CO_(2) consumption and methane production rate could be increased by changing the upper gas recirculation rate alone,but the increase effect was not obvious,but the by-product hydrogen production decreased significantly.Changing the lower liquid circulation rate alone can effectively promote the growth of biofilm,and change the properties of biofilm at the later stage of the experiment,with the peak current density increased by 16%;The methanogenic rate decreased from the peak value of 0.561 to 0.3 mmol/d,and the CO_(2) consumption did not change signifi-cantly,which indicated that CO_(2) was converted into other organic substances instead of methane.The data after coupling the upper gas circulation rate with the lower liquid circulation rate is similar to that of only changing the lower liquid circulation rate,but changing the upper gas circulation rate can alleviate the decline of methane pro-duction rate caused by the change of biofilm properties,which not only improves the current density,but also increases the methane production rate by 0.05 mmol/d in the stable period.This study can provide theoretical and technical support for the industrial application scenario offlowfield regulation intervention of microbial elec-trolytic cell methanogenesis.展开更多
碳捕获和封存路线(carbon capture and storage,简称CCS)和生物甲烷路线是实现二氧化碳减排的两种重要途径。但CCS路线存在捕集成本高的难题,而生物甲烷路线规模小、尚处于起步阶段。本文从经济和技术角度对比了两种路线减排二氧化碳的...碳捕获和封存路线(carbon capture and storage,简称CCS)和生物甲烷路线是实现二氧化碳减排的两种重要途径。但CCS路线存在捕集成本高的难题,而生物甲烷路线规模小、尚处于起步阶段。本文从经济和技术角度对比了两种路线减排二氧化碳的优缺点,发现生物甲烷路线理论捕集能耗仅为CCS路线的一半,且捕集条件温和,更有利于提高吸附剂材料的容量、降低捕集成本,因而生物甲烷路线更具有减排潜力。为了解决CCS和生物甲烷路线目前存在的困境,提出了CCS与生物甲烷耦合、借助CCS加速发展生物甲烷过程的新思路。展开更多
基金This paper is supported by Shanghai Science and Technology Development Fund,China,No.19DZ1205604.
文摘Reducing CO_(2) to produce methane through microbial electrolytic cell(MEC)is one of the important methods of CO_(2) resource utilization.In view of the problem of low methanogenesis rate and weak CO_(2) conversion rate in the reduction process,theflowfield environment of the cathode chamber is changed by changing the upper gas cir-culation rate and the lower liquid circulation rate of the cathode chamber to explore the impact on the reactor startup and operation and products.The results showed that under certain conditions,the CO_(2) consumption and methane production rate could be increased by changing the upper gas recirculation rate alone,but the increase effect was not obvious,but the by-product hydrogen production decreased significantly.Changing the lower liquid circulation rate alone can effectively promote the growth of biofilm,and change the properties of biofilm at the later stage of the experiment,with the peak current density increased by 16%;The methanogenic rate decreased from the peak value of 0.561 to 0.3 mmol/d,and the CO_(2) consumption did not change signifi-cantly,which indicated that CO_(2) was converted into other organic substances instead of methane.The data after coupling the upper gas circulation rate with the lower liquid circulation rate is similar to that of only changing the lower liquid circulation rate,but changing the upper gas circulation rate can alleviate the decline of methane pro-duction rate caused by the change of biofilm properties,which not only improves the current density,but also increases the methane production rate by 0.05 mmol/d in the stable period.This study can provide theoretical and technical support for the industrial application scenario offlowfield regulation intervention of microbial elec-trolytic cell methanogenesis.
文摘碳捕获和封存路线(carbon capture and storage,简称CCS)和生物甲烷路线是实现二氧化碳减排的两种重要途径。但CCS路线存在捕集成本高的难题,而生物甲烷路线规模小、尚处于起步阶段。本文从经济和技术角度对比了两种路线减排二氧化碳的优缺点,发现生物甲烷路线理论捕集能耗仅为CCS路线的一半,且捕集条件温和,更有利于提高吸附剂材料的容量、降低捕集成本,因而生物甲烷路线更具有减排潜力。为了解决CCS和生物甲烷路线目前存在的困境,提出了CCS与生物甲烷耦合、借助CCS加速发展生物甲烷过程的新思路。
