Numerical simulation study on the influence of blasting location on blasting fume diffusion in deep open-pit mines

The special structure of deep open-pit mines makes it difficult to diffuse and dilute the blasting fume produced by blasting, which seriously endangers the life safety and health of production workers.Based on the real mine, the 2-D model of the deep open-pit mine has been established.The influence of the blasting location on the blasting fume diffusion is investigated by unsteady numerical analysis method.The results show that recombination circulations are formed in open pit under different blasting locations, the blasting location is the critical factor influencing the airflow structure of open pit.The maximum concentration of blasting fume in the open pit decrease gradually with time, but the descent rate decrease gradually, the concentration of blasting fume show a downward trend with three stages.The maximum concentration of blasting fume and the time of the fume concentration descending to safe concentration in the backwind locations are much higher than that in the upwind locations.When the blasting location is in the backwind side, the maximum concentration of blasting fume and the time of the fume concentration descending to safe concentration decrease first and then increase with the height of the blasting location decreasing.When the explosion location is in the upwind side, the maximum concentration of blasting fume and the time of the fume concentration descending to safe concentration increase with the height of the blasting location decreasing.The research has a positive instruction for the safety production and the mine workers’ health in deep open-pit mines.