Study On The Movement Deposition Law And Exposure Risk Of Metal Ore Dust In The Respiratory Tract

With the booming mining industry,the respiratory health of mining operators needs urgent attention.In order to analyze the deposition position and amount of mineral dust in respiratory tract,reveal the movement rule of mineral dust in human respiratory tract,and provide guidance and suggestions for the scientific occupational protection work of workers in the mineral dust industry.Based on the numerical simulation study of mineral dust in human respiratory tract,this paper established the respiratory exposure risk evaluation system of mineral dust,and the research conclusions are as follows:(1)Taking metal ore dust with high risk of occupational disease as the research object,eight common metal ore dust samples were taken,and the physical characteristics of each mineral dust were measured by experimental methods such as particle size,density,shape,specific surface area and so on.Ansys and other software were used to establish a threedimensional model of the complete respiratory tract of the human body from the oral cavity to bronchi,and to simulate the movement and deposition of metal ore dust in the respiratory tract.(2)Clarify the deposition law of mineral dust in the human respiratory tract.The kinematic deposition of mineral dust in the respiratory tract is affected by density,particle size and labor intensity.The greater the density and particle size of the ore dust,the more obvious the sedimentation in the respiratory tract,and the higher the influence of the particle size of the ore dust.For mineral dust with a particle size greater than 1mm,the sedimentation rate of respiratory mineral dust increases with the increase of particle size and labor intensity,of which mineral dust of more than 5.21 μm will all be deposited in the respiratory tract and the throat deposition rate is greater than 85%.The ore dust is mainly deposited in the posterior part of the throat,at the tracheal vortex,and the escape location is mainly the lateral bottom segment bronchi of the left lower lobe and the lateral bottom segment of the right lower lobe.(3)Based on the kinematic deposition of mineral dust in the human respiratory tract and the dust removal time of the human slime cilia system,the respiratory exposure risk assessment of mineral dust is established,and the appropriate respiratory protective equipment is proposed for the operators.Taking the sampling of eight common mineral dusts as examples for application,the recommendations are as follows:Under mild labor intensity,intermittent work or changing of the guard can be combined with respiratory protective equipment.Under medium and heavy labor intensity,the way of respiratory protection protective equipment with high protection coefficient is adopted.The selection of protective equipment is determined based on the exposure risk level of each mineral dust.