Research On Coal Damage Characteristics And Gas Migration Law Of Coal Containing Gas

Through experimental research, theoretical analysis, numerical simulation and field practice,conduct the deep gas of coal seam open coal rock damage fracture characteristics and the gasmigration law research. Firstly using mercury injection, scanning electron microscopy andtransmission electron microscopy to study deep gas coal seam coal with different coal ranksample’s pore and fissure structure characteristics, combined with the isothermal adsorption test toanalyze reservoirs’ occurrence state of gas within coalbed with different coal rank; then conductmechanical damage characteristics, adsorption and seepage and evolution of the whole process ofstress and strain test of the two kinds of containing gas coal in gas-solid coupling, simple coalmatrix fracture system model is established, determine coal matrix’s deformation characteristics inthe three states of balance, low pressure and overpressure; accomplish seepage and acousticemission parameters of synchronous monitoring of crude instability and failure in all the stress andstrain process, explain the mechanism of acoustic emission of coal containing gas and deduce coalcontaining gas medium damage equation based on acoustic emission, obtain damage deformationregularity of coal containing gas based on the acoustic emission characteristics and time-spaceevolution mechanism; gas-solid coupling model is established and inserted in multi-physicscoupling analysis software, the mechanism of deep ground coal gas migration influenced byground stress and gas pressure are studied; Finally, through investigation three-dimensionaldrainage system of the deep coal mine rich in gas, evaluate the gas control technology of deepwell low gas permeability coal seam based on this system.