The Study On Gas Desorption And Flow Law In Coal Of Dual-porosity

The occurrence condition of coal seam in our country is complex and changeable,the mechanism of gas desorption and the law of gas flow in broken coal have not beensufficiently studied. To solve this problem, this paper focuses on the research of gasflow in coal of dual pore structure. It firstly uses the combined methods of experiment,theoretical analysis and numerical simulation to obtain the law of gas flow in lumpcoal; then, it set up the mathematical model of gas desorption and flow in coal of dualpore structure by analysis of gas desorption and its flow process after the coalexcavation, and it makes the software of coal gas flow engineering analysis using thefinite difference method to discrete the model and Visual basic language to design theprogram of the discrete model; finally, through the numerical experiments, thedistributions of gas pressure and content in the fracture and its surrounding lump coalare obtained, as well as the law of gas emission from the fracture and the law of gasdesorption and diffusion in lump coal. The results will provide the scientific basis forthe study on the technologies of increasing permeability and extracting gas in coalseam with low permeability and high gas, at the same time, it will play the role oftheoretical guidance in efficient intensive mining.