Establish and Application on Prediction Model About Permeability of Coal Reservoir After Hydraulic Fracture

In order to obtain the permeability of the coal reservoir after hydraulic fracture, based on the pressure curve of the hydraulic fracturing and the principle of testing permeability by injection /fall-off well-test, the prediction model about the permeability of the coal reservoir after hydraulic fracture was established. According to the data of the exploration and development about coalbed methane in Panzhuang Block of Jincheng Mine Area and in Encun Block of Jiaozuo Mine Area, the accura cy and effectiveness of the model was verified.The results showed that the proportion of耳and IV class in the coal seam section and whether connecting the anomaly s tructure belt after hydraulic fracturing were important influence on the accuracy of the prediction results. When the proportion of and IV class in the coal seam sectio n was small, the fracturing could easily form in the hard coal, the prediction results were accurate. When the proportion of I and IV class in the coal seam section was larger, the fracturing fluid could easily flow in the coal particles and coal particles, the prediction results could not reflect the fracturing effect.