Optimization And Evaluation Of Gas Drainage Technology In Huangling Mining Area

With the exploitation of coal resources in the Huangling mining area,the amount of mine gas emission has increased year by year,and coal seam gas in the production working face has abnormally emerged.Due to the sudden,concealed and large amount of gas,the gas concentration in the mining face will exceed the limit,resulting in stagnation of mining,increasing the difficulty of monitoring,endangering the safety of workers,and becoming a new disaster factors about safe and efficient city in Huangling Mining.In this paper,based on the different gas content and complicated extraction methods in Huangling mining area,the field measurement,theoretical analysis and industrial test are combined.According to the actual measurement,the original gas content of No.2 coal seam is 2.56m3/t,and the residual gas content.after extraction is 0.99?1.18m3/t.The gas adsorption constant a of No.2 coal seam measured by high capacity method is 20.047?22.647m3/t,the b value is 0.474?0.551 MPa-1;according to the gas permeability coefficient and the gas flow attenuation coefficient,the No.2 coal seam is determined to be an easy type of extraction.By comparing the gas pressure,gas content and gas concentration,the different drilling arrangements,different sealing lengths,different sealing materials,drilling spacing and other factors in the same section are obtained.The attenuation coefficient of the borehole gas has a great influence,and the refined gas drainage in the sub-area can effectively improve the extraction effect.Based on the occurrence of coal seam gas in Huangling mining area,the law of coal seam gas migration was analyzed,a drainage model suitable for gas extraction of the coal seam in Huangling mining area was established,and the determination of different drainage methods using the residual gas content as a key index was determined.The best extraction method for different gas content areas in Huangling mining area was obtained.At the same time,it provides support for the digging,pumping,and recovery of Huangling mining area,which has created tremendous economic benefits and provided guidance and reference for the future gas extraction of the coal seam.