China Nonferrous Metallurgy

As a crucial equipment in the smelting process, the performance of the lance directly influences the stirring effect of the airflow on the melt. In this study, a physical model of an immersed multi-channel lance with a length of approximately 800mm used in the anode slime side-blown furnace was established. Numerical simulation studies of gas flow and heat transfer processes inside the lance were conducted based on the SSTk-ω turbulence model. The distribution characteristics of gas temperature, flow velocity, and pressure inside the lance were analyzed. The variation characteristics of airflow pressure along the flow direction under different flow rates of natural gas and oxygen-enriched air, the relationship between flow rate and outlet velocity, and the cooling effect of airflow rates on the lance were investigated. The findings suggest that the multi-channel structure of the lance enhances the outlet velocity and reinforces the cooling effect of the gas flow. However, significant pressure loss occurs at abrupt changes in the cross-section of the airflow channel and at the outlet section, hindering the enhancement of the outlet velocity. With the increase of airflow rates, the outlet velocity of the lance increases significantly, and the pressure loss at the outlet segment of natural gas and oxygen-enriched air reaches 40% and 25% of their inlet total pressure, respectively. Additionally, the cooling effect of flow rate on the lance is significant, with a decrease of approximately 15K in the temperature of the outlet section for every increase of 5Nm³·h^-1 and 10Nm³·h^-1 in flow rate for natural gas and oxygen-enriched air, respectively.