Research On Pressure-Relief Gas Drainage Technology Optimization And Outburst Prevention Reliability In Outburst Risky Coalseams

Due to the gas dynamic disaster accident severity, the current situation ofprotect layer mining with pressure relief gas extraction technologies got rapiddevelopment. Based on fundamental theories like rock mechanics, elastic mechanics,used numerical simulation and site inspection, the stress distribution laws andfracture deformation processes of protect layer mining was established under thecondition of coal seams. On the basis of theoretical researches, the pressure-reliefgas drainage methods were summarized and optimized. The mode of gas extractiontechnology aims at the protective layer and the protected layer were stated. Theevaluation index system of protective layer mining and pressure relief gas drainagetechnology was established. Finally, process control theory was applied to the coalmine gas control engineering, the initial framework of the Intelligent Control Systemof Mine Gas Management was built. The research results has the theoretical guidingsignificance to the practical application of protect layer mining with pressure reliefgas extraction technologies.The varying pattern of mining length and layer spacing along with surroundingrock stress and strata movement in roof and floor after mining of upper protectivelayer and lower-protective layer was studied in this paper. Connecting with theactual development of mine pressure-relief gas technology, basing on the object ofthe extraction technology and the methods of gas extraction, this paper summarizingthe modes of protective layer and gas extraction technology and the protectived layerand gas extraction technology. The methods and parametes of gas extraction wasoptimized. That provide examples and references for the plan of gas minister project.According to the characteristics of the technique with protective layer miningand mine pressure-relief gas, This paper puts forward a multilevel index to controlthe technology and quality in each link, Constructs a index system of protective layermining and gas extraction, which have7parents indexes and20sub-indexes. Then,based on the actual assessment of each index in a large number of engineeringapplications, Statistical validation shows each index control effect on the engineeringlink, Given the critical value of each index which is suited to the actual situation inour country’s most mining areas, It is convenient to promote the index system ofprotective layer mining and gas extraction.Analysis based on the main factors that affect the reliability of protective layermining technology, in the article, the reliability evaluation index system of protectivelayer mining technology is divided into the target layer, criteria layer and sub-criterialayer, and the basic theory of the Analytic Hierarchy Process is used to judgmentmatrix to calculate various indicators weight. Calculate the important degree ofdifferent indicators and indicators are divided into "important(value≥0.6)","moreimportant(0.03≤value<0.06)" and "general(value<0.3)" three categories.“theprotected layer mining design”,“the pressure-relief gas drainage”,“the coal pillar”,“the managerment of unprotected area” and “the outburst prevent control” shouldpay more attention. Finally, based on the characteristics of gas control mode of the existing coalmine, the concept of process control is introduced, build the process model of coalmine gas control process. Apply intelligent control systems of gas control to theprocess control of tunneling process in713workface of Qinan coalmine, and obtaingood results, preliminary achieve standardization and procedures of gas controlprocess.