晋牛矿1303综放面采空区注氮方案研究及数值模拟

为了合理设计采空区注氮防灭火方案，以晋牛煤矿1303综放工作面为研究对象，通过在采空区进、回风侧布置束管监测系统，连续测定采空区气体浓度变化，划分采空区自燃“三带”分布区域,并基于采空区自燃“三带”划分标准和数值模拟的方法，利用流体力学COMSOL计算软件，研究不同注氮量、注氮位置下采空区氧化自燃带的分布规律。研究结果表明:注氮量和注氮位置参数的变化，对氧化自燃带上界限的影响并不显著，而对氧化自燃带的下界限影响比较显著；最合适的注氮位置应该在距离切顶线30 m左右，运用Origin软件得出注氮量与氧化自燃带宽度呈指数关系，由拟合式计算出最优注氮量为386 m3/h，此时氧化自燃带的宽度为31.5 m。

Research and numerical simulation on nitrogen injection scheme in goaf of 1303 fully mechanized caving face in Jinniu mine

In order to reasonably design the scheme of fire prevention and control with nitrogen injection in the goaf, taking the 1303 fully mechanized caving face in Jinniu coal mine as the research object, the change of gas concentration in the goaf was measured continuously through arranging the beam tube monitoring system at the inlet air side and return air side of the goaf, then the distribution area of the spontaneous combustion "three zones" in the goaf was divided. Based on the division standard of the spontaneous combustion "three zones" in the goaf and the numerical simulation method, the distribution laws of oxidation spontaneous combustion zone in the goaf under different nitrogen injection quantities and positions were studied by using the fluid dynamics calculation software COMSOL. The results showed that the change of nitrogen injection quantity and position had no significant influence on the upper limit of the oxidation spontaneous combustion zone, and had significant influence on the lower limit of the oxidation spontaneous combustion zone. The most appropriate nitrogen injection position should be about 30 m away from the top cut line. It was obtained that there existed an exponential relationship between the nitrogen injection quantity and the width of the oxidation spontaneous combustion zone by using Origin software, and the optimum nitrogen injection rate was 386 m3/h calculated by the fitting formula, at the moment, the width of the oxidation spontaneous combustion zone was 31.5 m.