Study on Seepage Laws in Coal Bed Methane Mining Through Injecting Thermal in Low Permeability Coal Seam

In order to research seepage laws in low permeability and high storage coal seam through injecting heat, through laboratory tests, it was concluded that critical threshold temperature was 350 ℃ when the permeability of 3# coal seam of Shanxi Xucun Coal Mine happened great changes under temperature effect; thermal-fluid-solid mathematical model of injecting heat in low permeability coal seam is concluded through the theoretical analysis; based on this model, numerical simulation is used to study seepage regulation of low permeability and high storage coal seam through injecting heat under the action of heat-fluid-solid coupling. The results show that with the increase of injection time, coal seam permeability is increasing, when the injection time is 5 h, the coal seam permeability increases about 14 times than the original permeability, thermal effect is obvious, and thermal injection has little effect on change of coal seam permeability after 5 h.