Optimization of controlled circulating ventilation and oxygen supply scheme for high-altitude mine heading face based on CFD

Abstract

With the depletion of mineral resources in the plains, Chinese mining industry has shifted to higher altitudes where low pressure and low oxygen has become a bottleneck limiting further development of mining technology. The traditional diffusion type of oxygen supply has low oxygen utilization. Controlled circulation ventilation offers a good alternative for oxygen supply to workers in high altitude mines. In this study, a CFD approach was used to conduct a single factor analysis of circulating duct height, distance between circulating duct outlet and heading face, oxygen supply duct height, forcing duct air velocity and circulating duct air velocity to investigate their effects on the oxygen mass fraction located at the heading face. In addition, an orthogonal experiment was designed to analyze the effect of the above five factors on the distribution of oxygen mass fraction in the heading face. The results showed that the effect of forcing duct air velocity on the oxygen mass fraction in the heading face was the greatest. The average oxygen mass fraction in the heading face is highest when the height of circulating duct was 0.9 m, the distance between circulating duct outlet and heading face was 2 m, the height of oxygen supply duct was 1.0 m, the air velocity of forcing duct was 3 m/s and the air velocity of circulating duct was 2.5 m/s.