基于均压系统结合负压通风治理工作面低氧问题的研究

Research on the treatment of hypoxia problem in working faces based upon pressure equalization system combined with negative pressure ventilation

为解决石圪台煤矿浅埋深近距离煤层群开采过程中工作面回风隅角氧气浓度低、一氧化碳体积分数超限、回采过程中上覆采空区与地表导通形成漏风通道导致漏风现象等问题,以石圪台煤矿22101综采工作面为例,在原负压通风的基础上构建均压通风系统,使采空区以及工作面风压维持均衡,从而减少有毒有害气体涌入回采工作面威胁矿工的生产安全。研究表明,浅埋深工作面采空区气体压力变化易受大气压变化的影响,风压平衡工况点不固定,煤层埋深不大于140 m、近距离煤层群开采层间距在35~45 m的区间范围,上覆采空区浮煤留存量较大、临近煤层开采等待时间较长的工作面,采用均压通风结合负压通风系统可极大程度的解决工作面氧气浓度低、一氧化碳体积分数较高等问题,确保工作面安全生产。

In order to solve the problems of low oxygen concentration and excessive carbon monoxide volume fraction in the return air corner of the shallow buried and close range coal seam group mining process,and air leakage phenomenon caused by the air leakage channels formation between the overlying goaf and the surface during the recovering process,taking the 22101 comprehensive mining face in Shigetai Coal Mine as an example,a pressure equalization ventilation system was constructed on the basis of the original negative pressure ventilation system to maintain a balanced air pressure in the goaf and working face,in order to reduce the threat of toxic and harmful gases entering the mining face and endangering the production safety of miners.Research result shows that the gas pressure changes in the goaf of shallow buried deep working faces are easily affected by changes in atmospheric pressure,the operating point of wind pressure balance is not fixed,and the coal seam burial depth is not greater than 140 meters,the interval between close range coal seam mining layers is within the range of 35-45 meters,the retention of floating coal is relatively large in overlying goaf,the use of uniform pressure ventilation combined with negative pressure ventilation system can greatly solve the problems of low oxygen concentration and high carbon monoxide volume fraction in the working face with a large amount of floating coal retention in the overlying goaf and a long waiting time for coal seam mining to ensure the safe production in working faces.