1.School of Safety Science and Engineering, Liaoning Technical University, Fuxin , China;2.School of Mining,Liaoning Technical University, Fuxin , China;3.Shanxi Coking Coal Group Corporation Limited, Taiyuan , China;4.Research Institute of Safety Engineering and Technology, Liaoning Technical University, Fuxin , China

基于近距离煤层自燃防治理论研究和现场实践,以氧浓度控制为核心,提出以多点监测自反馈注氮为主的上覆采空区煤自燃综合防控技术。采用理论分析和数值模拟研究了巷道顶板裂隙发育对上覆采空区浮煤自燃的诱发机制,从氧浓度控制的角度对上覆采空区遗煤自燃防控进行了模拟分析与现场实践。研究结果表明,巷道顶板裂隙发育引起大面积漏风供氧是上覆采空区遗煤自燃灾害发生的重要诱因;遗煤自燃危险区位于上分层冒落三角区及终采线附近,且随漏风强度增大逐渐向回风侧扩展;相对传统多点注氮方式,采用多点自反馈技术可减少氮气用量36%以上,同时实现强漏风点的准确定位与区域遗煤氧化进程的动态监测。通过现场实践,验证了通过多点自反馈综合防控技术实现注氮量优化分配与强漏风点识别控制的可行性。

Based on the theoretical study and site practices on the spontaneous combustion prevention and control in the contiguous seams, taking the oxygen concentration control as the key, the paper provided the comprehensive prevention and control technology of the spontaneous combustion occurred in the overburden goaf with the multi point monitoring, automatic feedback and nitrogen injection mainly. The theoretical analysis and the numerical simulation were applied to study the induced mechanism of the coal spontaneous combustion in the overburden goaf caused by the fracture development in the mine roadway roof. From a view of the oxygen concentration control, a simulation analysis and the site practices were conducted on the prevention and control of the coal spontaneous combustion occurred in the overburden goaf. The study result showed that a large area air leakage and the oxygen supply caused by the fracture development in the mine roadway roof was the important incentive to cause the coal spontaneous combustion in the overburden goaf. The coal spontaneous combustion danger zone was located in the roof falling delta area of the top slicing and near the mining terminal line. With the air leakage intensity increased, the coal spontaneous combustion danger zone would be expanded to the air return side steadily. In comparison with the conventional multi point nitrogen injection method, the multi point automatic feedback technology could reduce the nitrogen consumption over 36%. Meanwhile,the accurate positioning of the high air leakage point and the dynamic monitoring of the regional coal oxidation process were realized. The site practices showed that the comprehensive prevention and control technology with the multi point automatic feedback could realize the feasibility to have the optimized distribution of the nitrogen injection volume and the recognition and control of the high air leakage point.

国家自然科学基金青年科学基金资助项目(51604144,51574143)；辽宁省自然科学基金资助项目(20170540430)；