Research On Gas Drainage Mode Of Low Permeability Coal Seam In Yanlong Coalfield

Gas extraction is the fundamental for the gas control and it is also of great significance for the prevention to gas accidents. This thesis takes the Guocun typical "three soft" coal mine in Yanlong coalfield as a test, uses the combination of the analysis of existing data, field parameters measured, computer simulation and field rials investigated technical solutions, researches of the mine gas drainage drilling blind arrangement, the lack of scientific basis problems in order to optimize the drilling arrangement and reached the purposes of improving gas drainage efficiency. At last, put forward the comprehensive gas drainage model in line with the mining conditions.The main research contents of the article:Firstly, to analyze the necessity of the coal seam gas extraction, drainage system arranged status and the problems based on basic parameters of coal seam gas measured underground mine. Then, using of ithology comprehensive evaluation method theory, UDEC numerical simulation method simulated the Gob "vertical three zones" distribution to determine the fracture with a height range combined twol coal mine roof and floor rock features. Then further using of Fluent simulation software simulated the goaf gas movement rules under U-shaped ventilation in mine Working Face; Finally, It is raised the gas comprehensive drainage patterns in line with the conditions of the coal mine.By the statistics of study effect, after application of integrated gas drainage patterns, face gas comprehensive drainage rate increased to 40.50%, the gas concentrations below 0.5% in return air parallel groove of working face, reduced the possibility of mine gas outburst and protected the mine production safety. It is of high reference value for the selection about YanLong Coalfield in twol coal seam's gas drainage method.