Abstract
Usually mercury intrusion/extrusion curves reflect the characteristics of open pore-fracture system of coals. Using this method, the nature of the open pore-fractures of 18 Chinese coals (varying in vitrinite reflectance from 0.65 to 1.76% Ro, max) was studied. A quantitative evaluation method for micropore (0-0.1 μm, in diameter), mesopore (0.1-1 μm), macropore (1-10 μm) and fracture (>10 μm) within coals was established by the mercury intrusion curves. The method was verified by the fractal geometry theory. Moreover, three Types (I, II and III) of the open pore-fracture systems of coals were analyzed by combining mercury withdrawal efficiency and permeability with pore size distribution. Results show that (a) Type I coals are characterized by abundant open micropores (mean 62.8 vol. %) and rarely open fractures, which leads to a large minable potential but very low production rate for coalbed methane (CBM); (b) Type II coals have low minable potential and high production rate for CBM, mainly because of the distribution of a few micropores (mean 35.5 vol. %) and a large number fractures (mean 19.7 vol. %) in coals; (c) Type III coals are the most appropriate to exploit CBM due to the existence of optimal open pore-fracture system (micropores, mean 58.5 vol. %; fractures, mean 15.4 vol. %) within coals.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
