Research On Fire Prevention Technology In Goaf Of The Close Coal Seam In Liuzhuang Coal Mine

Coal is the most important natural resource in my country.With the gradual advancement of coal mining,mine fire accidents occur frequently.When coal seams are mined at close distances,the upper and lower goafs are susceptible to interference to form more air leakage channels,which increases the probability of spontaneous combustion of coal in the goafs.Therefore,fire prevention in the goafs at close distances has become a concern for scientific researchers.One of the key research topics.In this paper,the 120502 working face of Liuzhuang Coal Mine is the research object,and the three-in-one research method of theoretical analysis,numerical simulation and field test is used to conduct theoretical research on the distribution of air leakage flow field in the goaf of close coal seam,coal spontaneous combustion mechanism and influencing factors.In-depth exploration of the basic characteristics of the porous medium in the goaf,and further analysis of the influence of these characteristics on the "three zones" division of air leakage and spontaneous combustion in the goaf,provides a relevant theoretical basis for the numerical simulation.With the help of FLUENT software,the air leakage flow field and oxygen concentration field in the goaf of 120502 working face of Liuzhuang Mine are numerically simulated and analyzed,and the distribution of spontaneous combustion"three zones" is determined.With reference to the actual measured oxygen concentration value on site,the "three-zone" contour map on the side of the air inlet lane in the goaf can be drawn,which is basically consistent with the distribution of the oxidation zone obtained by simulation.The oxygen concentration field is simulated under five conditions of 100m,150m,300m,400m,and 600m,and the dynamic distribution characteristics of the "three zones" of spontaneous combustion in the goaf are analyzed.Aiming at the spontaneous combustion risk area in the goaf of 120502 working face in Liuzhuang Mine,numerical simulation method is used to simulate the distribution of oxygen concentration in the goaf under four different nitrogen injection rates,and 750m3/h is the optimal nitrogen injection rate.According to the characteristics of the coal seam of the Liuzhuang Mine,the ventilation and fire prevention measures for the short-distance coal seam goaf are proposed to provide theoretical support and technical guidance for the safe production of the Liuzhuang Mine and other similar mines.Figure[38]Table[6]Reference[65]...