Frontiers of Earth Science

, Volume 13, Issue 1, pp 75–91 | Cite as

Effects of nano-pore system characteristics on CH4 adsorption capacity in anthracite

  • Chang’an ShanEmail author
  • Tingshan Zhang
  • Xing Liang
  • Dongchu Shu
  • Zhao Zhang
  • Xiangfeng Wei
  • Kun Zhang
  • Xuliang Feng
  • Haihua Zhu
  • Shengtao Wang
  • Yue Chen
Research Article


This study aims to determine the effects of nanoscale pores system characteristics on CH4 adsorption capacity in anthracite. A total of 24 coal samples from the southern Sichuan Basin, China, were examined systemically using coal maceral analysis, vitrinite reflectance tests, proximate analysis, ultimate analysis, low-temperature N2 adsorption–desorption experiments, nuclear magnetic resonance (NMR) analysis, and CH4 isotherm adsorption experiments. Results show that nano-pores are divided into four types on the basis of pore size ranges: super micropores (< 4 nm), micropores (4–10 nm), mesopores (10–100 nm), and macropores (> 100 nm). Super micropores, micropores, and mesopores make up the bulk of coal porosity, providing extremely large adsorption space with large internal surface area. This leads us to the conclusion that the threshold of pore diameter between adsorption pores and seepage pores is 100 nm. The “ink bottle” pores have the largest CH4 adsorption capacity, followed by semi-opened pores, whereas opened pores have the smallest CH4 adsorption capacity which indicates that anthracite pores with more irregular shapes possess higher CH4 adsorption capacity. CH4 adsorption capacity increased with the increase in NMR porosity and the bound water saturation. Moreover, CH4 adsorption capacity is positively correlated with NMR permeability when NMR permeability is less than 8 × 10–3 md. By contrast, the two factors are negatively correlated when NMR permeability is greater than 8 × 10–3 md.


CH4 adsorption capacity anthracite nanopore structure NMR physical properties 


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This research was funded by the Open Foundation of Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences) (No. TPR-2016-04), the Open Foundation of Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Mineral, (Shandong University of Science and Technology) (No. DMSM2017031), the Youth Science and Technology Innovation Fund Project (Xi’an Shiyou University) (No. 290088259), the National Science and Technology Major Project (No. 2017ZX05039001-002), the National Natural Science Foundation of China (Grant Nos. 41702127 and 41772150), the Scientific Research Program Funded by Shaanxi Provincial Education Department (No. 17JK0617).


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Copyright information

© Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Chang’an Shan
    • 1
    • 2
    • 3
    Email author
  • Tingshan Zhang
    • 4
  • Xing Liang
    • 5
  • Dongchu Shu
    • 5
  • Zhao Zhang
    • 5
  • Xiangfeng Wei
    • 6
  • Kun Zhang
    • 7
  • Xuliang Feng
    • 1
  • Haihua Zhu
    • 4
  • Shengtao Wang
    • 8
  • Yue Chen
    • 8
  1. 1.School of Earth Sciences and EngineeringXi’an Shiyou UniversityXi’anChina
  2. 2.Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary MineralsShandong University of Science and TechnologyQingdaoChina
  3. 3.Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences)Ministry of EducationWuhanChina
  4. 4.School of Geoscience and TechnologySouthwest Petroleum UniversityChengduChina
  5. 5.Exploration and Development DepartmentZhejiang Oilfield Company, CNPCHangzhouChina
  6. 6.SINOPEC Exploration CompanyChengduChina
  7. 7.State Key Laboratory of Petroleum Resources and ProspectingChina University of PetroleumBeijingChina
  8. 8.Shaanxi Yanchang Petroleum International Exploration and Development Engineering Co. LtdXi’anChina

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