抽采钻孔瓦斯浓度影响因素实验研究

Experimental study on influencing factors of gas concentration in drilling holes

为了研究抽采负压、瓦斯压力及透气性系数对瓦斯抽采浓度的影响。通过自主研发物理模拟井下瓦斯抽采影响实验平台,利用控制变量法,研究瓦斯抽采浓度随不同抽采负压、不同瓦斯压力及不同透气性系数变化规律。研究结果表明:当漏气量小于CO_(2)进气流量与CO_(2)纯量时,CO_(2)抽采浓度比较高,因此最佳抽采负压应该在30~40 kPa之间;CO_(2)进气流量随煤层初始压力提高而提高,CO_(2)纯量随煤层初始压力提高同样呈增长趋势;透气性系数增大时,提高抽采负压可以提高抽采浓度。

In order to study the influence of negative pressure,gas pressure and permeability coefficient on gas extraction concentration.Through the independent development of physical simulation of underground gas extraction influence experiment platform,through the control variable method,the variation law of gas extraction concentration with different negative pressure of gas extraction,different gas pressure and different permeability coefficient is studied.The results show that when the air leakage is less than the CO_(2) intake flow and the CO_(2) purity,the CO_(2) extraction concentration is relatively high,so the best negative pressure of extraction should be between 30-40 kPa.As the initial pressure of coal seam increases,the CO_(2) intake flow increases and the CO_(2) purity also increases.When the permeability coefficient increases,the pumping concentration can be increased by increasing the negative pressure of pumping.