宁东矿区复杂难采煤层工作面初采阶段工程实践

Engineering Practice in Initial Mining Stage of Working Face in Complex and Difficult Mining Seam in Ningdong Mining Area

复杂难采煤层工作面初采阶段煤岩体灾变过程是朝着不利于采场稳定性方向演化的过程,存在断层活化、煤壁片帮、顶板断裂和溃水溃沙等灾变现象。宁东矿区各矿井面临的开采环境日趋复杂,存在高温、埋深大、倾角大、地应力集中、软岩巷道支护困难、硬岩顶板破断不及时,极大地增加了开采难度。大倾角仰斜开采工作面,采场稳定性是决定安全开采的关键。国家能源集团宁夏煤业有限责任公司金家渠煤矿综采工作面初采阶段面临大倾角+仰斜、坚硬基本顶不破断、支架失稳、架前顶板整体切顶冒落等开采难题,是宁东矿区复杂难采煤层的典型代表,本文分析物质与能量在灾变中的传递转化形态,预测和评估灾变发生的可能性、危害性,针对最薄弱的链条环节,切断灾害传递途径,制订并执行"断链"控灾方案,历时8个月施工使工作面生产趋于正常,探索出适合宁东矿区复杂难采煤层工作面的"断链"控灾方法。

The coal and rock mass catastrophic process in the initial mining stage of complex and difficult mining seam working face is an evolution process that is not conducive to the stability of the stope. There are catastrophe phenomena such as fault activation,coal wall spalling,roof breaking,water and sand break.The mining environment of mines in Ningdong mining area is becoming more and more complex,including high temperature, large buried depth, large inclination, concentrated in-situ stress, unstoppable soft rock roadway and untimely breaking of hard rock roof,which greatly increase the mining difficulty. For up-dip mining working face with large inclination,stope stability is the key to determine safe mining. As a typical representative of complex and difficult mining seam in Ningdong mining area,the fully mechanized working face of CHN Energy Ningxia Coal Industry Co.,Ltd. Jinjiaqu Coal Mine is faced with mining problems such as large inclination + up-dip mining,breaking failure of hard rock roof,support instability,and overall cutting roof caving of the front roof of the frame in the initial mining stage. This article analyzes the transmission and transformation form of material and energy in the catastrophe,predicts and evaluates the possibility and harmfulness of the catastrophe,cuts off the disaster transmission path for the weakest chain link,formulates and implements the“chain cutting”disaster control scheme,and carries out construction for 8 months so that the production of the working face tends to be normal,and develops the“chain cutting”disaster control method suitable for the working face of complex and difficult mining seam in Ningdong mining area.