孟加拉国Barapukuria矿开采VI煤层平均厚度39.14 m，采用多分层错距布置的减损开采模式，地质条件复杂，原始地温高，自燃火灾、水害、热害、冲击地压等地质灾害严重。针对孟巴矿多分层错距开采采空区遗煤量大、立体漏风供氧通道多、遗煤失水、地温高等利于煤自燃的环境条件，首先通过采空区煤自燃“三带”观测、漏风通道分析、张裂带和断层等因素的理论叠加，划分了多分层错距开采煤自燃危险区域范围和危险等级，确定了工作面最小安全推进速度；其次，通过不同含水煤样的程序升温实验和Graham系数获得了煤自然发火标志气体、特征温度阈值、预警指标及阈值，结合采空区、老空区以及巷帮危险区分布特征，提出了多分层开采煤自燃危险区域“时空−分级−适配”的监测预警方法；根据孟巴矿多分层错距开采特点及多年现场实践，形成了危险区域“立体封堵、分段隔离、区域注氮”的精准预防和灾变气体“溯源控漏、减量稀释、定向疏排”的应急控制技术。现场应用结果表明：该技术的实施，确保了一分层1110工作面的安全启封，解放呆滞煤量80万t；此外，有效控制了各分层工作面正常回采过程中采空区的遗煤氧化进程，进风侧采空区CO为0，回风侧采空区CO短时间快速减小为0，成功地保障了孟巴矿十多年的安全开采。

The average thickness of VI coal seam in Barapukuria mine in Bangladesh is 36 m. The damage reduction mining mode with layered staggered arrangement is adopted. The geological conditions are complex, the original ground temperature is high, and the geological disasters such as spontaneous combustion fire, water damage, heat damage and rock burst are serious. In view of the environmental conditions conducive to coal spontaneous combustion, such as large amount of residual coal in goaf, many three-dimensional air leakage and oxygen supply channels, water loss of residual coal and high ground temperature in multi-layer staggered mining of Mengba Mine, firstly, through the theoretical superposition of' three zones' observation of coal spontaneous combustion in goaf, air leakage channel analysis, tension fracture zone and fault, the range and risk level of spontaneous combustion danger area in multi-layer staggered mining are divided, and the minimum safe advance speed of working face is determined. Secondly, through the programmed temperature rise experiment of different water-bearing coal samples and Graham coefficient, the coal spontaneous combustion marker gas, characteristic temperature threshold, early warning index and threshold are obtained. Combined with the distribution characteristics of goaf, goaf and roadway dangerous area, the monitoring and early warning method of “space-time-classification-adaptation” for spontaneous combustion dangerous area in multi-layer mining is proposed. According to the characteristics of layered staggered mining in Mengba Mine and many years of field practice, the precise prevention of “three-dimensional plugging, segmented isolation, regional nitrogen injection” in dangerous areas and the emergency control technology of “traceability control leakage, reduction dilution, directional drainage” of catastrophic gas are formed. The field application results show that the implementation of this technology ensures the safe unsealing of the 1110 working face of the first layer, and liberates 800,000 tons of stagnant coal. In addition, the oxidation process of residual coal in the goaf during the normal mining process of each stratified working face is effectively controlled. The CO in the goaf on the air inlet side is 0, and the CO in the goaf on the air return side is rapidly reduced to 0 in a short time, which successfully guarantees the safe mining of Mengba Mine for more than ten years.