连通采空区压差波动机制及抑燃阻逸技术研究

The Mechanism of Pressure Difference Fluctuation in Connected Goaf and the Technology of Fire Prevention and Control Gas Escape

摘要: 针对大面积连通采空区漏风网络复杂、采空区内外压差波动明显导致“呼吸现象”突出，易引发采空区遗煤自燃及有毒有害气体异常涌出等问题，以俄霍布拉克煤矿5号煤层52105和52107工作面连通采空区为研究对象，采用SF₆气体示踪法、压能测定及密闭压差长期监测等方法，分析连通采空区漏风区域及内外压差变化规律，并提出抑燃阻逸综合防控技术。结果表明：52105、52107采空区水平与垂直方向均具有一定连通性，52105和52107采空区密闭区域表现出较明显的漏风趋势；冬季密闭内外压差在−20~40 Pa范围内波动，夏季在−10~15 Pa范围内波动，均呈现明显的日周期变化及正负压交替特征；大气压力与密闭压差变化具有较明显的对应关系，地表温度主要通过影响大气压力间接作用于密闭压差。采取密闭加固、裂隙封堵及压差–注氮动态调控等综合防控措施后，采空区压差波动范围控制在−10~10 Pa以内，正负压大幅交替现象基本消失，“呼吸现象”明显减弱。有效防控采空区遗煤自燃及有毒有害气体逸散风险。

Abstract: Aiming to address complex air leakage networks, pronounced pressure-difference fluctuations, and the “breathing phenomenon” in large-area connected goafs, which may induce spontaneous combustion of residual coal and abnormal emissions of toxic and hazardous gases, the connected goafs of the No. 52105 and 52107 working faces in the No. 5 coal seam of Okhobrak Coal mine were investigated. The SF₆ tracer-gas method, pressure measurements, and long-term monitoring of sealing pressure differences were employed to characterize air leakage and pressure-difference variations. An integrated control technology combining fire suppression, air-leakage mitigation, and pressure-difference-nitrogen injection regulation was proposed. The results show that the two goafs are partially connected both horizontally and vertically, with pronounced air leakage in the sealed regions. The sealing pressure difference fluctuates between −20 and 40 Pa in winter and −10 and 15 Pa in summer, exhibiting clear daily periodicity and alternating positive and negative pressure. Atmospheric pressure is closely correlated with the sealing pressure difference, while surface temperature mainly affects it indirectly through atmospheric pressure. After implementing sealing reinforcement, fracture sealing, and dynamic pressure-difference-nitrogen injection regulation, the pressure-difference fluctuation was controlled within −10 to 10 Pa, the positive-negative pressure alternation was largely eliminated, and the “breathing phenomenon” was significantly weakened, effectively mitigating the risks of residual-coal spontaneous combustion and toxic and hazardous gas emissions.