Research On The Wind Curtain Dust Control Law Of Mixed Dust Removal System At Tashan Mine's Heaving Face

The high dust production,concentration and pollution of coal mine dust has been a major problem threatening the physical and mental health of underground workers and mine safety.Taking effective measures to control dust pollution in coal mines and minimizing dust concentration is the top priority in preventing dust hazards.Based on the hybrid dust removal system,the equation of motion of dust and its settling law in the air are analyzed and determined based on the research object at the excavation face of Tashan coal mine in Datong,Shanxi.It is clarified that the settling velocity of dust particles in the static air is proportional to the square of particle size,and Fluent numerical simulation is used to analyze the dust production mechanism and its transport law at the coal mine excavation face.The dust and wind flow movement law before and after the installation of the wall-mounted duct is analyzed,and the dust control effect of the wall-mounted duct on the dust in the header is studied and the parameters are optimized.The research results show that:(1)At the workplace of the road header operator,the wall-mounted air duct will form a rotating air curtain due to the wind flow,thus forming a wind wall to shield the dust at the workplace of the road header driver and prevent the dust from spreading into the roadway and affecting the breathing environment of the operator.(2)After the hybrid dust removal system is installed with attached wall ducts,the extractor ducts are used to extract dust under the swirling action of the wind curtain air flow,and the dust is extracted from the header tunnel,thus reducing the dust concentration.(3)Using the control variables method,the velocity of the wind cylinder and the wind speed of the pressurized wind cylinder were analyzed in different proportions after the installation of the attached wind cylinder,and the dust diffusion range would be changed under different velocity comparison cases,with the wind curtain installation location,wind curtain size parameters and other conditions remaining unchanged.By analyzing the numerical simulation results,it is concluded that the best dust dispersion control effect can be achieved when the attached wind screen is installed 2 m away from the air outlet of the pressure wind screen,the size is 1 m×0.8 m×0.06 m,and the speed of the pressure wind screen is 11 m/s,the speed of the attached wind screen is 26 m/s,and the ratio of the speed of the pressure wind screen to the speed of the attached wind screen is approximately 3:1,which can prevent and control the dust dispersion in front of the workers,that is,8 m away from the digging face position.(4)Based on the above research results,field engineering application in Shanxi Datong China Coal Tashan coal mine,the results show that the dust removal system with attached wall ducts in the hybrid dust removal device is more effective than the dust diffusion control without installation,and the dust removal efficiency can be controlled at about 94% with the installation of wind curtain device.The paper has 24 figures,9 tables,and 63 references.