Research and development on enrichment of low concentration coal mine methane by adsorption technology

doi:10.11949/j.issn.0438-1157.20180602

Abstract

Abstract:

China is a country with more coal, less gas and lean oil. The coalbed methane reserves are about 30 trillion cubic meters. Due to the lack of advanced and practical separation technology for the low concentration coal mine methane (CMM), only about 50% total drained CMM is utilized at present. The recovery and utilization of low concentration CMM provide a number of significant energy, economic and environmental benefits. Situation of extraction and utilization of CMM resource in China is briefly introduced. Research on adsorption materials and adsorption processes for the enrichment of low concentration CMM in recent years have been surveyed and future research on these two areas has been discussed. The adsorption capacity and selectivity of the adsorbents is low when they are used to separate low concentration coal mine methane. And the performance of the typical pressure swing adsorption (PSA) process is limited. Finally, the development of adsorbents with high CH₄ adsorbed amount and high CH₄/N₂ selectivity and novel PSA process are proposed for the future enrichment of low concentration coal mine methane.

Key words: low concentration coal mine methane, adsorption, adsorbents, enrichment of methane, separation

摘要：

我国是一个多煤少气贫油的国家，煤层气储量约30万亿立方米，由于缺乏先进实用的低浓度煤层气甲烷分离浓缩技术，当前抽采煤层气利用率仅为50%左右。因此，对低浓度煤层气甲烷富集浓缩过程开展研究，可在开发能源的同时减少温室气体的排放，具有重大的应用价值和战略意义。简要介绍了我国煤层气资源开发利用情况，综述了近年来低浓度煤层气吸附浓缩技术研究进展，包括新型吸附材料及先进吸附工艺。对于低浓度煤层气中CH₄/N₂分离，目前文献报道吸附材料的吸附容量及分离系数仍然处于较低水平；受吸附材料的分离性能较差影响，传统变压吸附工艺对低浓度煤层气中CH₄浓缩效果并不理想。最后指出，高吸附容量、高选择性吸附材料及多种方法结合的新型吸附工艺是未来低浓度煤层气吸附浓缩技术的发展方向。

关键词: 低浓度煤层气, 吸附作用, 吸附剂, 甲烷浓缩, 分离

CLC Number:

TQ028.8

YANG Ying, QU Donglei, LI Ping, YU Jianguo. Research and development on enrichment of low concentration coal mine methane by adsorption technology[J]. CIESC Journal, 2018, 69(11): 4518-4529.

杨颖, 曲冬蕾, 李平, 于建国. 低浓度煤层气吸附浓缩技术研究与发展[J]. 化工学报, 2018, 69(11): 4518-4529.

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