A Study on Geological Factors to Control Gas Drainage of Boli Basin

摘要

With the increasing of mining depth in Boli basin,gas accident probability is entering into the high stage.In order to control the gas accident,advanced drainage is required.However,it depends on many geological factors whether drainage can achieve the desired effect.So,it is necessary that geological factors' study of gas drainage is carried out.By the analysis of the coal seam porosity,permeability and gas pressure,wall rock reservoir properties features,and geological structure features,the conclusion is that the basin coal seam porosity is mainly with tiny holes,adsorption quantity of coal seam gas is more,the free gas is less,and gas release is difficucoal seam permeability is not high,gas pressure is smaller,gas migration is difficult,and it is not good for gas drainage.Reservoir gas content of wall rock is low,permeability is low,and gas drainage effect is not ideal.It is better the influence of geological structure on gas drainage in the west than in the east.The geological conditions of Boli basin are bad for gas drainage.It adopts gas drainage and drainage hole encryption arrangement in order to control gas and it can obtain good results.