Study On Influence Of Mine Ventilation On Coal Wall Spontaneous Combustion In Xiaoji Han Coal Mine

With the advancement of the mining face and the development and extension of the roadway,the roadway cannot be processed In a timely and effective manner,resulting in poor ventilation of the coal pillar and coal wall leakage,making the isolated coal pillar coal at the 11212 working face of the Xiaoji han mine The spontaneous combustion and smoke phenomenon occurred on the wall in one day in 2018,which had a certain impact on the safety management of the mine’s ventilation and seriously affected the safety of the mine.Therefore,in order to guarantee the safe production of Xiaoji han Mine,it is necessary to conduct a safety analysis of the ventilation system and study the spontaneous combustion characteristics of coal walls.In this paper,firstly,the barometer point by point measurement method is used to measure the ventilation resistance,analyze the distribution of ventilation resistance and simple safety analysis in Xiaoji han mine.The measured data are set as the basic parmeters in the auxiliary software of mine ventilation.On this basis,the calculation results are basically consistent with the actual ventilation situation.and according to the simulated calculated wind The pressure can be calculated and the differential pressure between the two ends of isolated coal pillar in 11212 working face is 433.89Pa.Secondly,2 coal samples collected on site were crushed and screened into 1～6 coal samples.Six coal samples were placed in the temperature progranmed box for coal spontaneous combustion characteristics experiment The oxidation products in the experiment process were analyzed by gas chromatography.The critical temperature and dry cracking temperature of Xiaoji han coal sample were 60～70℃ and 115～125℃,repectively.When the coal temperature readied 100℃,the CO concentration of 1000 ppm could be used as coal self ignition The judgment standard of burning.Thirdly,the coal spontaneous combustion of isolated coal pillar in 11212 walking face was simulated by using fluent coal spontaneous combustion of isolated coal pillar in 11212 working face was simulated by using fluent simulation software.The results show that under the conditions of 433.89Pa coal pillar differential pressure and 1m2 fracture channel,the CO concentration reaches 1000ppm,and the coal wall of coal pillar spontaneous combustion occurs.Finally,according to the influencing factors of coal spontaneous combustion conditions(differential pressure 433.89Pa,crack rate 0.013 and moisture 11.43%～16.31%),the spontaneous combustion risk area was predicted and early warning was carried out in Xiaojihan coal mine.Only 11212 working face withdrawal channel isolated coal pillar was obtained in the high-risk area.According to the division of coal spontaneous combustion stage,the spontaneous combustion stage of Xiaojihan mine spontaneous combustion coal wall was judged,and the grouting technology of grouting was selected After the implementation of the gas concentration detection results show that the coal wall spontaneous combustion prevention effect is significant,there will be no coal spontaneous combustion.