NUMERICAL SIMULATION OF WIND-DRIVEN MICROPARTICLES GENERATED BY BLASTING IN A LIMESTONE QUARRY

Abstract

The problem of air pollution outside the quarry near the surface by blasting generated solid microparticles was considered in relation to the characteristic conditions of mining in Sitovsky limestone quarry in Lipetsk region. The average depth of the quarry is 50 m. The equivalent total power of the considered massive explosion was chosen to be 6 tons of TNT. The results were obtained by numerical solution of subsonic flow approximation of the Navier–Stokes equations in their full form for a compressible liquid. Eddy viscosity was taken into account within the framework of the Large Eddy Simulation method. The problem of wind-borne dust generation by explosion of single charge in borehole was solved. The size of the area where the concentration of microparticles with a size of less than 10 microns exceeds the maximum permissible values was estimated outside the quarry near the surface. It is shown that there is no dependence of the size of this area on the angle between the wind direction and the side of the quarry, and the size of the area in the wind direction is approximately 10 km in all the cases considered. The width of the time interval in which the concentration of microparticles exceeds the maximum permissible value near the surface varies from 5 minutes at a distance of 1 km to 15–20 minutes at a distance of 7 km from the quarry side and does not depend on the wind direction.