Wang Aikuan, Shao Pei
Key Laboratory of Coalbed Methane Resources & Reservoir Formation Process, Ministry of Education, China University of Mining & Technology, Xuzhou 221008, China.
School of Resources and Geosciences, China University of Mining & Technology, Xuzhou 221116, China.
ACS Omega. 2022 May 18;7(21):18139-18145. doi: 10.1021/acsomega.2c01821. eCollection 2022 May 31.
Clarifying the effect of organic maceral on biogenic coalbed gas generation is important to understand the mechanism of biogenic coalbed gas generation and to develop bioengineering of coalbed gas. Bituminous coals in the Huainan mining area of China were selected as the research object, and the organic macerals were enriched through manual separation and floatation-sedimentation experiments first. Then, the simulated biogas generation experiments were carried out by using raw coal, single vitrinite, and inertinite, respectively. The results showed that all the bituminous coal, vitrinite, and inertinite could be biodegraded to generate biogas. The gas production yield of vitrinite was11.5 mL/g, which was more than that of raw coal (9.8 mL/g) and inertinite (6.26 mL/g). The production processes showed the stage characteristics of rapid increase and continuous decrease, but the gas production peak of inertinite lagged behind that of raw coal and vitrinite. Vitrinite content was positively correlated with total gas production, while inertinite could inhibit biogas production. CH composition in simulated biogas from vitrinite was the most, and that from inertinite was the least, while there was a positive correlation between vitrinite content and CH composition. The above evidence showed that vitrinite in bituminous coal is more easily biodegradable. There were significant positive correlations between chloroform bitumen "A", H, and H/C to total gas production, and they can be used as important indicators to evaluate the output of coalbed biogas.
阐明有机显微组分对生物成因煤层气生成的影响，对于理解生物成因煤层气的生成机制以及开展煤层气生物工程具有重要意义。选取中国淮南矿区的烟煤作为研究对象，首先通过手工分选和浮选-沉降实验富集有机显微组分。然后，分别采用原煤、单一镜质组和惰质组进行模拟沼气生成实验。结果表明，所有烟煤、镜质组和惰质组都可被生物降解产生沼气。镜质组的产气率为11.5 mL/g，高于原煤（9.8 mL/g）和惰质组（6.26 mL/g）。产气过程呈现快速增加和持续下降的阶段特征，但惰质组的产气峰值滞后于原煤和镜质组。镜质组含量与总产气量呈正相关，而惰质组会抑制沼气生成。镜质组模拟沼气中的CH含量最高，惰质组的最低，且镜质组含量与CH含量呈正相关。上述证据表明，烟煤中的镜质组更易被生物降解。氯仿沥青“A”、H以及H/C与总产气量之间存在显著正相关，它们可作为评估煤层生物气产量的重要指标。
