煤层气(英语:coalbed methane)是指被吸附在煤层中的甲烷。因其不含硫化氢而被称为“甜气” [1] 。这种气体在地下煤矿开采中时,会溢出造成安全风险。近几十年来,从煤层中提取的天然气已成为美国、加拿大、澳大利亚和其他国家的重要能源[2][3]

煤层气与典型的砂岩或其他常规气藏不同,因为煤层气甲烷是吸附在煤层孔隙和裂缝中 [4]。煤层气几乎不含丙烷或丁烷等重碳氢化合物,而且不含天然气凝析油。煤层气是由干酪根和其他有机质的热裂解成熟而形成的[5] [6]。煤层气中所含的气体主要是甲烷和微量的乙烷、氮气、二氧化碳和少量其他气体。

煤层气储层被认为是双孔隙储层。其中天然裂缝是负责流动而基质的孔隙度是负责储气[5]

参考文献

  1. ^ Moore, Tim A. (2012). "Coalbed methane: A review". International Journal of Coal Geology. 101: 36–81. doi:10.1016/j.coal.2012.05.011. ISSN 0166-5162.
  2. ^ US Energy Information Administration, Coalbed methane production, accessed 9 Oct. 2013
  3. ^ Geoscience Australia, Coal seam gas Archived 16 October 2013 at the Wayback Machine, accessed 10 Oct. 2013
  4. ^ McKee, C. R., Bumb, A. C., & Koenig, R. A. (1988, March 1). Stress-Dependent Permeability and Porosity of Coal and Other Geologic Formations. Society of Petroleum Engineers. doi:10.2118/12858-PA
  5. ^ 5.0 5.1 Laubach, S. E; Marrett, R. A; Olson, J. E; Scott, A. R (1 February 1998). "Characteristics and origins of coal cleat: A review". International Journal of Coal Geology. 35 (1): 175–207. doi:10.1016/S0166-5162(97)00012-8. ISSN 0166-5162
  6. ^ Saurabh, Suman; Harpalani, Satya (15 March 2018). "Modeling of microbial methane generation from coal and assessment of its impact on flow behavior". Fuel. 216: 274–283. doi:10.1016/j.fuel.2017.12.015. ISSN 0016-2361