Application Of The Floor Charge Technology In Coal Seam Permeability Improvement

Our country is a energy consumption big country, and coal occupies a large part in the energy structure, and with the increase of coal mining depth, especially in Huainan-Huaibei areas, the buried depth and permeability is inversely proportional, which causes gas outburst more danger in the process of coal mining. How to eliminate the coal and gas outburst has become an important research topic. In recent years, deep hole pre-split blasting has been applied in anti-reflection with hazard of coal and gas outburst, such as coal bedding anti-reflection, shaft uncovering coal and so on, but the influence of charge position of though layer anti-reflection blasting on coal seam anti-reflection effect has no further study.In this paper, the influence of charge in coal seams and coal floor on coal seam permeability has been analyzed respectively through the laboratory experiment and numerical simulation combined with field test. Results show that, blasting disturbance radius is lesser, anti-reflection duration is shorter, and charge is difficult if charge in coal seam,. But if charge in coal floor, charge is convenient, blasting disturbance radius is larger as a result of coal floor rock is fit for rockhole. That floor rock crack is not easy to close, and crack on interface of coal and rock is interpenetration make anti-reflection duration longer. This topic in charge design of low permeability gas coal seam anti-reflection has a certain guiding significance.