煤系页岩总有机碳含量与成熟度对厌氧发酵产甲烷性能的影响  

Investigation on the effects of total organic carbon content and maturity of coal measure shale on biomethane production performance in the anaerobic digestion system

作　　者：阮倩雯 王乾 苏现波[1,2,3,4] 赵伟仲 高富博 RUAN Qianwen;WANG Qian;SU Xianbo;ZHAO Weizhong;GAO Fubo(School of Resources and Environment,Henan Polytechnic University,Jiaozuo 454000,China;Unconventional Gas Research Institute,Henan Polytechnic University,Jiaozuo 454000,China;School of Energy Resources,China University of Geosciences,Wuhan 430074,China;Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region,Jiaozuo 454000,China)

机构地区：[1]河南理工大学资源环境学院,河南焦作454000 [2]河南理工大学非常规天然气研究院,河南焦作454000 [3]中国地质大学资源学院,湖北武汉430074 [4]中原经济区煤层(页岩)气协同创新中心,河南焦作454000

出　　处：《煤炭学报》2024年第12期4883-4896,共14页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(42202209,42230804);中国博士后基金资助项目(2022M711055)。

摘　　要：煤系页岩气是煤系气的重要组成部分,且煤系页岩具有丰富的本源微生物和微生物代谢所需的分散有机质,这使得其具有厌氧发酵产甲烷的可能性,并为煤系气开发阶段的可采资源提供补充。然而,针对煤系页岩厌氧发酵产甲烷机制的研究仍缺乏,生物甲烷产出特征及其控制因素仍未清楚,限制了该方法的发展与应用。以不同地区的煤系页岩为研究对象,以煤系页岩本源菌群为试验菌群,通过厌氧发酵试验探讨其产甲烷潜力,评价总有机碳(TOC)含量、成熟度(R_(o))对产甲烷效果的影响。结果表明:在本源微生物作用下煤系页岩普遍具有产甲烷能力,累计产量最高可达1.97 mL/g。煤系页岩厌氧发酵产甲烷周期一般为15 d,产量变化规律与煤相似,但周期明显缩短。根据微生物降解复杂有机质的代谢模型,可将煤系页岩厌氧发酵产甲烷过程划分为水解产酸、产氢产乙酸和产甲烷3个阶段。生物甲烷产量与煤系页岩TOC含量具有明显的正相关性,尤其当TOC含量大于10%,甲烷产量显著提升。另外,生物甲烷产量与R_(o)呈负相关性,当R_(o)增大至3.78%,几乎不再产生。煤系页岩TOC含量与R_(o)主要在水解产酸阶段发挥作用,随TOC含量降低、R_(o)增大,微生物降解页岩有机质产生的氨基酸等代谢产物减少,使得产氢产乙酸和产甲烷阶段微生物代谢所需的底物的物质的量浓度降低,最终生物甲烷产量减少。Coal measure shale gas is an important component of coal measure gas,and it is rich in in-situ microorganisms and dispersed organic matter required for microbial metabolism,making it possible to produce biomethane through anaerobic digestion,and providing supplements for the recoverable resources during coal measure gas development.However,the systematic studies on the methanogenesis mechanism of coal measure shale in the anaerobic digestion system are still limited,and the characteristics of biological methane production and its controlling factors remain unclear,which hinders its development and application.Coal measure shales from different regions were selected as the research object,and the in-situ microorganisms were enriched as the experimental microorganisms.Through some anaerobic digestion experiments,the biomethane production potential of the coal measure shales as well as the effects of total organic carbon(TOC)content and maturity(R_(o))on the methanogenesis were studied.The results show that coal measure shales generally possess the ability to produce biomethane under the action of in-situ microorganisms,and the cumulative production reaches up to 1.97 mL/g.The biomethane production cycle of the shales is generally 15 d.According to the metabolic model of microbial degradation of complex organic matter,the methanogenesis process of anaerobic digestion of coal-measure shale can be divided into three stages:hydrolysis stage,hydrogen-producing acetogenic stage,and methanogenesis stage.There is an obvious positive correlation between the biomethane production and the TOC content of the shales.Especially when the TOC content is greater than 10%,the biomethane production increases significantly.Also,biomethane production is negatively correlated with the R_(o).When the R_(o)increases to 3.78%,the shales almost no longer produce biomethane.The TOC content and R_(o)of the coal measure shale mainly exert their influence in the hydrolysis stage.As the TOC content decreases and R_(o)increases,the amino acids an

关 键 词：煤系页岩 厌氧发酵 生物甲烷 有机碳含量 成熟度 

分 类 号：Q819[生物学—生物工程] Q815