Theoretical Analysis and Validation of Factors Affecting the Permeability on Coal Containing Gas

Abstract:

Based on definition of porosity, permeability model of gas-bearing coal was build which took porosity gas pressure, gas adsorption expansion, temperature and crustal stress into account, and the factors affecting the permeability of gas-bearing coal has been analyzed theoretically. The results show that permeability decreased exponentially with crustal stress increasing, permeability decreased linearly with temperature increasing and permeability decreased first and then increased with gas pressure increasing; crustal stress had the strongest effect than gas pressure and temperature, decreasing crustal stress was the most effective way to increase permeability and to improve extraction; the results verified by experiments data show that the smaller error and the higher prediction accuracy can meet production practical requirement, which could provide some guidance to gas extraction.

• Periodical: Advanced Materials Research (Volumes 962-965)
• Pages: 1112-1117
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.962-965.1112
• Online since: June 2014
• Authors: Gang Xu*, Rui Feng Ma, Quan Bin Mou
• Keywords: Coal Permeability, Gas Adsorption Expansion, Gas Pressure, Porosity, Temperature

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DOI: 10.1144/gsl.sp.1996.109.01.14