Study On Dust Distribution Characteristics And Control Technology Of Fully Mechanized Working Face In Hongliulin Coal Mine

With the continuous improvement of the mechanization of the mine,the problem of coal mine dust is becoming increasingly prominent.In particular,dust is the greatest hazard in some coal mines in northern Shaanxi where Geological conditions are good and coal seams are stable and the hazards of water,fire and gas are relatively small.Based on the practice of Hongliulin coal mine,this paper has carried out the research on integrated dust control technology through theoretical analysis,field measurement and field experiment.The main conclusions are as follows:Increasing water content in coal body can reduce the amount of coal dust generated during coal mining and bind primary fine dust into larger dust particles.The numerical simulation results of coal seam water injection show that within a certain range of water injection pressure,the greater the water injection pressure,the greater the wetting radius.However,when the injection pressure is higher than 8MPa,the increase of wetting radius is no longer obvious and is weakened by the influence of water injection pressure.The field application of coal seam water injection shows that the water content of coal seam increases by 31.4%,the respirable dust decreases by 45.4%and the total dust concentration decreases by 48.2%on average.The effect of water injection and dust prevention measures has been achieved.The main dust sources in the fully mechanized coal face of Hongliulin Coal Mine are analyzed:coal cutting dust,shifting frame dust,coal falling dust,coal falling and transportation dust.25208 after adopting the spray measure,the dust reduction rate is 65.4%.The distribution of dust concentration in working face air flow is analyzed.The amount of dust taken away by ventilation is larger than the amount of dust supplied by diffusion.The dust concentration decreases,and the effect of air leakage dispersion is remarkable.The best ventilation and dust removal speed is determined to be 1.3?1.5m/s.Through the comprehensive dust control strategy of "source control,process control",the integration of mine comprehensive dust control has been realized,the dust concentration in production and operation sites has been reduced,the phenomenon of mine dust exceeding the standard has been effectively controlled,and the dust hazard has been reduced.