Numerical simulation for capture performance analysis and optimization of exhaust hoods in aluminum smelting furnaces

In the smelting process of aluminum processing plants, the high temperature soot emission intensity and concentration are high, which is harmful to the indoor and outdoor environment and human health. In order to improve the capture efficiency of local exhaust hoods in aluminum smelting furnaces, this paper studies the relationship between the capture efficiency of exhaust hoods and the dimensionless exhaust air volume (the ratio of exhaust hood exhaust air volume to soot emission volume). Based on the principle of vortex elimination and the characteristics of airflow entrainment, an optimization method for the capture performance of exhaust hoods is proposed. The research shows that when the dimensionless exhaust air volume is less than 3.2, increasing the exhaust air volume will significantly improve the capture efficiency of the exhaust hood, which is the air volume economic zone. After optimizing the geometric characteristics of the exhaust hood, the soot escape rate can be reduced by about 20% and the system exhaust air volume can be reduced by 6.1% to 44.1% in the air volume economic zone.