| The belt transport roadway is one of the most serious places for mine dust pollution.The belt transport roadway is also the key place for coal mine dust control work.There is a large amount of dust in the transport lane,among which the hydrophobic dust is the most difficult to control.Aiming at the treatment of hydrophobic dust,a combination of theoretical analysis,numerical simulation,laboratory experiments,and field applications is used to carry out research on dust migration in belt conveyor lanes and active magnetization spray dust reduction technology,and to prevent and control dust pollution in belt lanes in coal transportation.significant.Based on the case study of Mindong No.1 Mine,the main research results are as follows:The air flow distribution and dust distribution characteristics in the belt transport roadway are studied by numerical simulation and simulation experiment methods.Through numerical simulation calculation,it is concluded that during the belt transportation process,the dust distribution above and on both sides of the transportation belt is the most,and the dust on both sides of the transportation belt is the most.It has a relatively large speed,and the dust passing through both sides of the blanking pipe in the belt transport roadway will have the maximum moving speed,and the quantity and speed of this part of the dust will decrease with the increase of the distance from the blanking pipe;No.2 in the belt transport roadway The wind flow from the upper roadway of the transfer point merges into the lower roadway,forming eddy currents near the roadway wall.The wind flow on the upwind side is seriously stratified.Taking the tape surface as the main layer,it can be roughly divided into the direction of upwind flow in the middle layer of the tape,the flow direction of the two sidewalls in the downwind direction,and the downwind side in the transfer direction.There is a wind vortex near the point,the wind flow is blurred in layers,and the wind flow direction is chaotic.The smaller the particle size of the dust,the stronger the ability to move with the wind flow,the smaller particle size dust is deposited farther,and the larger particle size dust settles near the transfer point;the experiment shows that the dust concentration in the roadway increases with the increase of the roadway ventilation speed.,the dust concentration in the roadway decreases with the increase of the dust moisture content,and the optimal range of the ventilation speed of the belt transport roadway is determined.In order to improve the treatment efficiency of hydrophobic dust,it is proposed to use active magnetization spray technology to control the dust in the belt transport lane.The spray atomization effect of seed water and the experimental dust reduction efficiency were compared and studied.The numerical simulation statistics and analysis of the droplet size distribution and kinetic energy distribution under different surface tensions were carried out.The diameter droplet has the highest content,and the 5μm particle size droplet has the highest monomer content;the working parameters such as nozzle aperture,nozzle air pressure,and water flow rate are selected through the control variable experiment;the dust concentration in the experimental device is measured by the weighing method,and the traditional pneumatic spray is measured separately.The dust reduction efficiency of magnetized spray and active magnetized spray on total dust and exhaled dust.The test results show that the exhalation and dust reduction efficiency of active magnetized spray is 96% greater than 94% of magnetized spray,and greater than 83% of traditional pneumatic spray.The technology improves the dust suppression efficiency of hydrophobic dust and has better application prospects.Aiming at the actual dust pollution problem in the belt transport lanes of Mindong No.1Mine,the application of active magnetization spray technology is studied.Based on the results of simulation experiments,the spray technical parameters were determined.According to the speed and position distribution characteristics of dust in the roadway,a "center suppression,two sides partition" active magnetization spray dust reduction layout plan was proposed.Arrangement of nozzles and corresponding equipment in the roadway forms a set of active magnetized spray dust control system.The dust concentration at the same measuring point before and after application was measured several times to obtain the dust reduction efficiency of the scheme.Compared with the traditional spray,the dust removal efficiency was improved by more than 15%.The study on the mechanism of dust movement and active magnetization spray dust reduction at the belt transfer point is of great significance to the dust prevention and control work in coal mines,the prevention of dust occupational diseases,and the improvement of workers’ working environment.The dissertation has 129 figures,18 tables,and 164 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