“呼吸”效应作用下浅埋极近距离煤层采空区群漏风机制及协同防控研究

Research on the Air Leakage Mechanisms and Prevention and Control Technologies for Goaf Groups in Shallow-Buried and Ultra-Close Coal Seams

  • 摘要: 浅埋极近距离煤层采空区群漏风网络极为复杂,外界气压扰动引发的“呼吸”效应为采空区煤自燃防治来极大挑战。本文以唐山沟煤矿83103工作面为工程背景,综合运用地表裂隙观测、能位测定与示踪技术,系统研究了极近距离煤层采空区群的漏风机制;通过地表不同气候、气温及气压等大气参数的变化揭示了采空区“呼吸”效应作用对上覆采空区有害气体异常下泄的扰动规律。研究结果表明:地表裂隙未与83103采空区有效贯通;83101轨道密闭墙是主要漏风源,83103工作面采空区与邻近及上覆采空区群相形成了“水平对流-垂直下泄”的立体漏风网络;“呼吸”现象受压差驱动;地表温度、地表大气压分别与压差呈正、负相关,在持续正压差的作用下,上覆采空区有害气体大量下泄。基于此,针对性提出了以均压调控、裂隙封堵、注浆加固、抽采置换为主的协同漏风防控体系;治理后83103工作面回风隅角CO浓度下降了48.6%,氧浓度恢复至正常值左右,有效减弱了浅埋极近距离煤层采空区群的气体交换,并降低了采空区煤自燃风险。本研究可为类似条件下采空区群漏风与煤自燃防治提供理论依据。

     

    Abstract: The leakage network in shallow, closely spaced coal seam goaf areas is highly complex, and the "breathing" effect caused by external pressure disturbances poses a significant challenge for fire prevention. Taking the 83103 working face of Tangshangou Mine as a case study, this research employed surface fracture observation, energy potential measurement, and tracer gas techniques to investigate leakage mechanisms between the surface and the goaf group. The study analyzed the influence of surface climatic conditions, temperature, and atmospheric pressure on the disturbance patterns of abnormal gas leakage from the overlying goaf. Results show that surface fractures do not directly connect with the 83103 goaf; the main leakage source is the sealed wall of the 83101 track gateway. A three-dimensional leakage network characterized by "horizontal convection–vertical leakage" was identified between the 83103 goaf and adjacent overlying zones. Driven by pressure differentials, this "breathing" phenomenon correlates positively with surface temperature and negatively with atmospheric pressure. Sustained positive pressure differentials lead to substantial release of harmful gases from the overlying goaf. A coordinated leakage control system—including pressure equalization, fracture sealing, grouting reinforcement, and gas drainage—was proposed and implemented. Following these measures, CO concentration at the return corner decreased by 48.6% and O? concentration returned to normal, effectively suppressing gas exchange and reducing the risk of spontaneous combustion in the goaf group. This study provides a theoretical basis for leakage and fire control in similar abandoned mining areas.

     

/

返回文章
返回