Simulation Study on Powder Movement and Diffusion Behavior Based on RH Up Snorkel Powder Injection Process

RH powder injection desulfurization significantly improves steel quality. By using argon gas flow to inject desulfurization powder at the up snorkel position, it effectively enhances desulfurization efficiency while reducing steel splashing and pollution. This paper focuses on the 210 t RH degasser and uses the VOF-DPM and component transport models to study the effects of factors such as powder injection nozzle height, particle size, and others on mixing time, powder residence, and movement. The results showed that powder mixing time decreased as the powder injection nozzle height decreased. The circulating flow rate (Q) of the RH degasser increased with the powder injection nozzle height (h), with the relationship given by Q = 0.558h + 10.177. When the powder injection air holes are set to 8, the average powder residence time in the vacuum chamber is minimized to 17 seconds. Under the 8-hole condition, the average residence time is reduced by 50 pct compared to the 1-hole setup and by 20.9 pct compared to the 12-hole setup. The circulation flow rate is 39.6 pct higher than that of the 1-hole setup and 3.4 pct higher than that of the 12-hole setup. The circulating flow rate increased by 14.9 pct when the powder particle size increased from 0.1 to 0.7 mm. When the powder-to-gas ratio is 0.3, the minimum mixing time is 147.61 seconds, and the maximum circulation flow rate is 492.04 m3/h. An increase in powder injection airflow significantly mitigates the impact of the powder-to-gas ratio.