Bio-methane,as a promising renewable green energy,the component and thermal value of which are very close to that of natural gas,indicates an enormous resource potential and could be employed as the alternative of fos...Bio-methane,as a promising renewable green energy,the component and thermal value of which are very close to that of natural gas,indicates an enormous resource potential and could be employed as the alternative of fossil energy through the development of agro-industrial integration and efficient bio-methane system. Establishment of high efficient agro-industrial integrated bio-methane system is an important component of the renewable energy system and also a significant way of emission reduction.展开更多
A coupled PHREEQC-MATLAB simulation approach is proposed to investigate the dynamic changes in rock porosity,gas storage capacity,formation water salinity,and reservoir temperature driven by biogeochemical interaction...A coupled PHREEQC-MATLAB simulation approach is proposed to investigate the dynamic changes in rock porosity,gas storage capacity,formation water salinity,and reservoir temperature driven by biogeochemical interactions during cyclic underground bio-methanation(UBM)of CO_(2)and H_(2),and to quantitatively examine how the evolution of these parameters influences CH_(4)production efficiency.The results indicate that during the cyclic UBM of CO_(2)-H_(2),the formation water undergoes a dynamic acid-base alternation,leading to periodic mineral dissolution and precipitation with limited impact on rock porosity.Across different mineral systems,the maximum CH_(4)production rate remains consistently around 3.6×10^(−3)mol/(L·d)in each cycle.With an increasing number of cycles,under high initial salinity conditions,the metabolic water produced by methanogens can significantly reduce the formation water salinity,gradually enhancing the CH_(4)production rate to levels comparable with those under low initial salinity.Additionally,the increased volume of produced water reduces the gas storage capacity of the reservoir.This reduction becomes more pronounced at higher initial CO_(2)-H_(2)pressures,accompanied by a more significant increase in CH_(4)production rate increment.Furthermore,the heat generated by methanogen metabolism leads to an increase in reservoir temperature,with the extent of temperature rise significantly influenced by heat loss.If the heat loss is neglected,the reservoir temperature can increase by up to 17.1℃after five cycles(10 years).When the reservoir has a higher initial temperature,the elevated thermal conditions may reduce CH_(4)production efficiency.展开更多
The present work dealt with the generation, purifying and liquefaction of biomethane to improve energy density using local materials for domestic applications. Cow dung was sourced at JKUAT dairy farm and experiments ...The present work dealt with the generation, purifying and liquefaction of biomethane to improve energy density using local materials for domestic applications. Cow dung was sourced at JKUAT dairy farm and experiments were conducted at JKUAT Bioenergy laboratory using biogas generated in laboratory scale 1 m<sup>3</sup> bioreactors. Experiments were done in triplicates and repeated under different conditions to get the optimal conditions. The results showed that enhanced cow dung substrate displayed an improved fermentation process with increased biogas yields. Purified biogas optimized methane content from 56% ± 0.18% for raw biogas to 95% ± 0.98% for biomethane which was ideal for liquefaction.展开更多
Amidst the rapid development of renewable energy,the intermittency and instability of energy supply pose severe challenges and impose higher requirements on energy storage systems.Among the various energy storage tech...Amidst the rapid development of renewable energy,the intermittency and instability of energy supply pose severe challenges and impose higher requirements on energy storage systems.Among the various energy storage technologies,the coupled approach of power-to-hydrogen(H2)and underground H2storage(UHS)offers advantages such as extended storage duration and large-scale capacity,making it highly promising for future development.However,during UHS,particularly in porous media,microbial metabolic processes such as methanogenesis,acetogenesis,and sulfate reduction may lead to H2consumption and the production of byproducts.These microbial activities can impact the efficiency and safety of UHS both positively and negatively.Therefore,this paper provides a comprehensive review of experimental,numerical,and field studies on microbial interactions in UHS within porous media,aiming to capture research progress and elucidate microbial effects.It begins by outlining the primary types of UHS and the key microbial metabolic processes involved.Subsequently,the paper introduces the experimental approaches for investigating gas-water-rock-microbe interactions and interfacial properties,the models and simulators used in numerical studies,and the procedures implemented in field trials.Furthermore,it analyzes and discusses microbial interactions and their positive and negative impacts on UHS in porous media,focusing on aspects such as H2consumption,H2flow,and storage safety.Based on these insights,recommendations for site selection,engineering operations,and on-site monitoring of UHS,as well as potential future research directions,are provided.展开更多
文摘Bio-methane,as a promising renewable green energy,the component and thermal value of which are very close to that of natural gas,indicates an enormous resource potential and could be employed as the alternative of fossil energy through the development of agro-industrial integration and efficient bio-methane system. Establishment of high efficient agro-industrial integrated bio-methane system is an important component of the renewable energy system and also a significant way of emission reduction.
基金Supported by the Horizon Europe Program(101129729)Sichuan Haiju Plan Project(2024JDHJ0012)China Scholarship Council Project(202208080058).
文摘A coupled PHREEQC-MATLAB simulation approach is proposed to investigate the dynamic changes in rock porosity,gas storage capacity,formation water salinity,and reservoir temperature driven by biogeochemical interactions during cyclic underground bio-methanation(UBM)of CO_(2)and H_(2),and to quantitatively examine how the evolution of these parameters influences CH_(4)production efficiency.The results indicate that during the cyclic UBM of CO_(2)-H_(2),the formation water undergoes a dynamic acid-base alternation,leading to periodic mineral dissolution and precipitation with limited impact on rock porosity.Across different mineral systems,the maximum CH_(4)production rate remains consistently around 3.6×10^(−3)mol/(L·d)in each cycle.With an increasing number of cycles,under high initial salinity conditions,the metabolic water produced by methanogens can significantly reduce the formation water salinity,gradually enhancing the CH_(4)production rate to levels comparable with those under low initial salinity.Additionally,the increased volume of produced water reduces the gas storage capacity of the reservoir.This reduction becomes more pronounced at higher initial CO_(2)-H_(2)pressures,accompanied by a more significant increase in CH_(4)production rate increment.Furthermore,the heat generated by methanogen metabolism leads to an increase in reservoir temperature,with the extent of temperature rise significantly influenced by heat loss.If the heat loss is neglected,the reservoir temperature can increase by up to 17.1℃after five cycles(10 years).When the reservoir has a higher initial temperature,the elevated thermal conditions may reduce CH_(4)production efficiency.
文摘The present work dealt with the generation, purifying and liquefaction of biomethane to improve energy density using local materials for domestic applications. Cow dung was sourced at JKUAT dairy farm and experiments were conducted at JKUAT Bioenergy laboratory using biogas generated in laboratory scale 1 m<sup>3</sup> bioreactors. Experiments were done in triplicates and repeated under different conditions to get the optimal conditions. The results showed that enhanced cow dung substrate displayed an improved fermentation process with increased biogas yields. Purified biogas optimized methane content from 56% ± 0.18% for raw biogas to 95% ± 0.98% for biomethane which was ideal for liquefaction.
基金supported by the European Union's“Horizon Europe programme”—LOC3G(Grant No.101129729)the Henan Center for Outstanding Overseas Scientists(Grant No.GZS2024001)。
文摘Amidst the rapid development of renewable energy,the intermittency and instability of energy supply pose severe challenges and impose higher requirements on energy storage systems.Among the various energy storage technologies,the coupled approach of power-to-hydrogen(H2)and underground H2storage(UHS)offers advantages such as extended storage duration and large-scale capacity,making it highly promising for future development.However,during UHS,particularly in porous media,microbial metabolic processes such as methanogenesis,acetogenesis,and sulfate reduction may lead to H2consumption and the production of byproducts.These microbial activities can impact the efficiency and safety of UHS both positively and negatively.Therefore,this paper provides a comprehensive review of experimental,numerical,and field studies on microbial interactions in UHS within porous media,aiming to capture research progress and elucidate microbial effects.It begins by outlining the primary types of UHS and the key microbial metabolic processes involved.Subsequently,the paper introduces the experimental approaches for investigating gas-water-rock-microbe interactions and interfacial properties,the models and simulators used in numerical studies,and the procedures implemented in field trials.Furthermore,it analyzes and discusses microbial interactions and their positive and negative impacts on UHS in porous media,focusing on aspects such as H2consumption,H2flow,and storage safety.Based on these insights,recommendations for site selection,engineering operations,and on-site monitoring of UHS,as well as potential future research directions,are provided.
