Methane adsorption constrained by pore structure in high rank coals using FESEM, CO2 adsorption and NMRC techniques

This research was funded by the National Natural Science Fund (grant nos. 41830427, 41772160 and 41602170), the National Major Research Program for Science and Technology of China (grant no. 2016ZX05043-001), Key Research and Development Projects of The Xinjiang Uygur Autonomous Region (grant no. 2017B03019-01) and the Fundamental Research Funds for Central Universities (grant no. 2652018002).Peer reviewedPublisher PD

Novel discrete fracture networks model for multiphase flow in coal

Acknowledgments This research was funded by the National Natural Science Foundation of China (Grants 41830427, 41922016, and 42130806) and the China Scholarship Council (202006400048).Peer reviewedPostprin

Propagation of pressure drop in coalbed methane reservoir during drainage stage

 Numerical simulation was employed to investigate the propagation speed of pressure drop at the drainage stage in coalbed methane (CBM) reservoirs. A seepage model of single-phase water in CBM reservoirs was generated with the parameter from CBM well ZS39 in the Zhengzhuang block of the southern Qinshui Basin. The effects of stress sensitivity and reservoir properties on the pressure drop propagation process were analysed. Moreover the pressure drop funnel scale index was introduced to quantitatively characterize the propagation process. The results indicate that stress sensitivity cause the permeability form the permeability drop funnel, which is consistent with the shape of the pressure drop funnel. Under the constant bottom pressure, the propagation speed of the funnel will gradually decrease in both longitudinal and lateral direction. And the overall propagation speed rapidly increases first and then gradually decreases. In the scenario of steady decrease in the bottomhole pressure, the pressure drop speed shows an increasing trend in the longitudinal direction, and a decreasing trend in the lateral direction. The overall propagation speed of the pressure drop funnel increases all along. The reservoir pressure drop is positively correlated with the initial porosity, the initial permeability and the elastic modulus. For Poisson ratio, when the ratio is small, the reservoir pressure drop has a negative correlation. As Poisson ratio increases over 0.35, a positive correlation exists. It was found from the sensitivity analysis of reservoir pressure drop that petrophysical parameters have strong sensitivity to pressure drop, especially for permeability. Therefore, this work may provide insights into the CBM reservoir properties, and thus will be favorable for improving CBM recovery.Cited as: Jia, D., Qiu, Y., Li, C, Cai, Y. Propagation of pressure drop in coalbed methane reservoir during drainage stage. Advances in Geo-Energy Research, 2019, 3(4): 387-395, doi: 10.26804/ager.2019.04.0

A new fracture permeability model of CBM reservoir with high-dip angle in the southern Junggar Basin, NW China

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was funded by the National Major Research Program for Science and Technology of China (2016ZX05043-001), the National Natural Science Fund of China (grant nos. 41602170 and 41772160), the Royal Society International Exchanges-China NSFC Joint Project (grant nos. 4161101405 and RG13991-10), and Key Research and Development Projects of the Xinjiang Uygur Autonomous Region (2017B03019-01).Peer reviewedPublisher PD

Investigation on the methane adsorption capacity in coals : considerations from nanopores by multifractal analysis

ACKNOWLEDGEMENTS This research was funded by the National Natural Science Foundation of China (grant numbers 41830427, 41922016, and 41772160).Peer reviewedPostprin

Insights into matrix compressibility of coals by mercury intrusion porosimetry and N2 adsorption

This research was funded by the National Natural Science Fund (grant nos. 41830427, 41602170 and 41772160), the National Major Research Program for Science and Technology of China (grant no. 2016ZX05043-001), the Key Research and DevelopmentProjects of the Xinjiang Uygur Autonomous Region (grant no. 2017B03019-01) and the Research Program for Excellent Doctoral Dissertation Supervisor of Beijing (grant no. YB20101141501).Peer reviewedPostprin

Scale-span pore structure heterogeneity of high volatile bituminous coal and anthracite by FIB-SEM and X-ray μ-CT

This research was funded by the National Natural Science Foundation of China (grant nos.41830427, 41922016, and 41772160) and the Fundamental Research Funds for Central Universities (grant no. 2652018002).Peer reviewedPostprin

Review on Applications of X-ray computed tomography for coal characterization : recent progress and perspectives

This research was funded by the National Natural Science Foundation of China (grant nos. 42130806, 41830427, 41922016 and 42102227).Peer reviewedPostprin

Size Distribution and Fractal Characteristics of Coal Pores through Nuclear Magnetic Resonance Cryoporometry

This research was funded by the National Natural Science Foundation of China (Grant no. 41602170), the Research Program for Excellent Doctoral Dissertation Supervisor of Beijing (grant no. YB20101141501), the Key Project of Coal-based Science and Technology in Shanxi Province-CBM accumulation model and reservoir evaluation in Shanxi province (grant no. MQ2014-01) and the Fundamental Research Funds for Central Universities (grant no. 35832015136).Peer reviewedPostprin

Microstructure Characterization Techniques for Shale Reservoirs : A Review

Funding This work was funded by the National Natural Science Foundation of China (Grant nos. U19B6003-03-01 and 42030804).Peer reviewedPublisher PD