Song Hongna, Lv Hang, Xia Daping, Tian Jixian
Institute of Business Administration, Henan Polytechnic University, Jiaozuo 454000, China.
Institute of Resources & Environment, Henan Polytechnic University, Jiaozuo 454000, China.
ACS Omega. 2024 Sep 23;9(39):40559-40565. doi: 10.1021/acsomega.4c04022. eCollection 2024 Oct 1.
Mudstone, a class of sedimentary rocks rich in organic matter, possesses considerable potential for biogas production. Mudstones possess a rich biological origin, which is conducive to refining the mechanisms and enrichment patterns of biogenic gas reservoirs. This has significant theoretical and practical implications for guiding the exploration and development of Quaternary mudstone gas reservoirs. Furthermore, the Qaidam Basin is an excellent place for the geological storage of CO due to its rich petroleum reservoir conditions. Experimental research on biogas production under diverse CO pressure-mudstone-microorganism-water interactions is conducted to determine the biogas production mechanism of mudstone under different CO pressures during sequestration circumstances. According to the results: (1) under supercritical carbon dioxide conditions, there is a slight initial increase in biogas production, followed by a gradual decrease. The periods and peaks of gas production vary among the different reaction groups. As carbon dioxide pressure increases, the gas production cycle lengthens significantly, while the gas yield declines. (2) Siderite and secondary carbonate minerals have increased in the mudstone's mineral fraction both before and after biogas production, while clay mineral groups have decreased. Specifically, there was a notable drop in chlorite and kaolinite. (3) Microorganism species in the system were analyzed, and the results showed that there was a gap in each microorganism's ability to adapt to its surroundings, and the diversity and quantity of bacteria declined with increasing pressure. After carbon dioxide was fluxed, there was a considerable shift in the pattern of biogas generation, which consequently had a major impact on the alterations in mineral fractions.
泥岩是一类富含有机质的沉积岩，具有巨大的生物气生成潜力。泥岩具有丰富的生物成因，有利于完善生物成因气藏的形成机制和富集模式。这对于指导第四系泥岩气藏的勘探开发具有重要的理论和实际意义。此外，柴达木盆地由于其丰富的油气藏条件，是二氧化碳地质封存的理想场所。开展了不同二氧化碳压力-泥岩-微生物-水相互作用下的生物气生成实验研究，以确定封存条件下不同二氧化碳压力下泥岩的生物气生成机制。结果表明：（1）在超临界二氧化碳条件下，生物气产量初期略有增加，随后逐渐下降。不同反应组的产气周期和峰值各不相同。随着二氧化碳压力的增加，产气周期显著延长，而产气量下降。（2） 生物气生成前后，泥岩矿物组分中的菱铁矿和次生碳酸盐矿物增加，而粘土矿物组减少。具体而言，绿泥石和高岭石有明显下降。（3） 对系统中的微生物种类进行了分析，结果表明各微生物对环境的适应能力存在差异，细菌的多样性和数量随压力增加而下降。通入二氧化碳后，生物气生成模式发生了显著变化，进而对矿物组分的变化产生了重大影响。
