Occurrence Law And Prediction Of Residual Gas From Drainage In Hudi Coal Mine Of Shanxi Coal Mine

Although the occurrence law of original gas in coal seam has been studied in depth,the research on the occurrence law of residual gas in coal seam after extraction is still lacking.Hudi Coal Mine has high gas content,and the distribution of residual gas after extraction has regional differences,which affects the safe production of coal mine.The research on the distribution of residual gas content has its practical production guiding significance.This paper takes No.3 coal seam of Hudi Coal Mine as the research object.On the basis of systematically collating and analyzing relevant data of Hudi Coal Mine,fresh coal samples are collected underground for mercury intrusion test,isothermal adsorption experiment and observation of micro-joints to study the physical characteristics of coal reservoirs in the mining area.By drawing maps of measured values of gas content in the mine,the occurrence characteristics of gas in the mine are analyzed,and then the influence on them is discussed.Distribution of geological factors;Based on the factors affecting the occurrence of raw coal gas,the geological control factors of residual gas content are quantitatively analyzed for 1303 working face in the mine;with the original coal gas content,structural curvature value,burial depth,coal thickness and corresponding residual gas content value as training samples in 1303 working face,the BP neural network for residual gas content prediction is established by using the software of matlab.The prediction of 1305 working face is also made.No.3 coal belongs to anthracite with high coalification degree;macropore and visible pore are the most developed,mesopore is not well developed,and the proportion of pore and micropore is equal;isothermal adsorption curve belongs to descending type and equilibrium type,and the adsorption capacity of coal seam is slightly poor to medium level;the dominant trend of micro-fracture is NWW,NNW,NEE and NNE.Hudi Coal Mine belongs to high gas mine;the gas content of raw coal shows the characteristics of "high in East and low in west".The difference of different structural types and lithology of roof and floor will affect the gas occurrence,and the burial depth,coal thickness and coal rank are generally positively correlated with the gas content of raw coal;the abnormal situation will occur in single factor analysis,because the gas occurrence is the result of comprehensive influence of many factors.The distribution of residual gas in 1303 working face is characterized by "high in the East and low in the west".In the south of the working face,the main influencing factors are raw coal gas content,burial depth and coal seam thickness;in the north of the working face,the main influencing factors are structural curvature;structural curvature and coal seam thickness are negatively linearly correlated with residual gas content,while the content of raw coal gas,burial depth and residual gas content are positively correlated.Relevant relationship.According to the prediction,the distribution of residual gas content in 1305 working face shows the characteristics of "high in the north and low in the south".In the south of the working face,the residual gas content can be reduced to less than 5 m3/t,while in the north of the working face,the residual gas content value is mostly greater than 7 m3/t.The paper includes 47 pictures,32 tables and 101 references.