七台河新立矿近距离薄煤层群煤与瓦斯共采技术

 七台河新立矿区具有煤层薄、透气性差、煤坚固性系数小、瓦斯含量高等特点，同时煤层群具有分组性，各组内煤层间距较小。为解决邻近层瓦斯涌出量大、顺层钻孔施工难度大、本煤层抽放效果差，回采工作面上隅角和回风流中瓦斯浓度容易超限等难题，提出了顶板高位近水平长钻孔瓦斯抽采技术，构建了新立矿区近距离薄煤层群煤与瓦斯共采技术体系，并在新立矿区进行了应用研究。本文在邻近层卸压瓦斯抽采技术原理分析的基础上，采用UDEC4.0数值模拟软件计算得出采空区冒落带和裂隙带高度为6～8m和18～20m。抽采结果表明，顶板高位钻孔组瓦斯抽采技术治理瓦斯效果明显，上隅角瓦斯体积分数稳定在0.8%以下，且钻孔抽采瓦斯体积分数达55%以上，抽采量达50m3/min以上，实现煤与瓦斯安全高效共采。

Joint Mining Technology of Gas and Coal in Thin Seam Group with Closed Distance in Qitaihe Xinli Mine

Xin Li Mining Area of Qi Taihe has the features of thin seam, low permeability, the low coefficient of coal sturdiness and the high gas content. Coal seams have the character of subgroups and at the same time the coal seam distance is small in every subgroup. We advanced the high-flat-seam drilling of gas extraction and built the system of simultaneous extraction of coal and gas of close-quarter thin seams of Xin Li Mining Area to solve the problems of the high gas emission of the adjacent seams, the difficult construcion of drilling of cis layers, the bad effect of the extraction and the over-limited gas concentraction of the upper corner at mining face and the return current. We studied and applied all those mentioned above in Xin Li Mining Area. On the basis of analyzing the theory of gas extraction of the adjacent seams, we calculated that the height of the area of dropping stones of goaf was 6-8m and the height of the crack area was 18-20m by using the software of UDEC4.0 numerical simulation. According to the results of the extraction, we got the conclusion that the control of gas by high roof drilling of gas extraction could get better effect, the gas volume fraction of upper corner was below 0.8%, the gas volume fration of drilling could be above 55% and the quantity of the extraction could be above 50m3/min. Therefore, it could achieve the high-efficiency simultaneous extraction of coal and gas.