RH侧底喷粉精炼过程流动特性

Flow characteristics of RH reactor side-bottom powder injection refining process

建立了一个数值模型来研究120 t RH喷粉过程中的气-液-固多相流动。考察了真空室、上升管、下降管和钢包底部4个位置喷粉对粉剂分布和钢液循环流量的影响。建立物理模型得到粉剂分布和局部速度,并对数值模拟进行了验证。结果表明,数值模型预测结果和实验结果较为吻合。采用真空室和上升管位置喷粉时,RH内粉剂分布行为相似,且RH内粉剂高浓度区域大于下降管喷粉和钢包底喷粉。下降管喷粉在熔池中存在大量粉剂浓度“死区”。钢包底喷粉可以增加22.6%的循环流量;下降管喷粉会降低36.6%的循环流量。喷粉过程对循环流量的影响主要源自于喷粉载气。除RH钢包底喷粉外,其他位置喷粉,粉剂存在会减小循环流量。

A numerical model was developed to study the gas-liquid-solid multiphase flow in 120 t RH-degasser. The effects of four powder injection positions, namely, the vacuum chamber, the up snorkel, the down snorkel and the ladle bottom, on the powder distribution and circulating flow were investigated. A physical model was developed to obtain the powder distribution and local flow velocity for validating the numerical model. The results show that the numerical model predictions agree well with the measured results. When the powder is injected from the vacuum chamber and the up snorkel, respectively, the powder distribution behavior in RH is similar, and the high powder concentration zone is larger than that injected from the down snorkel and the ladle bottom. There is a large powder concentration "dead zone" in the molten bath when the powder is injected from the down snorkel. Ladle bottom powder injection can increase the circulation flow rate by 22.6%, while the powder injection from the down snorkel decreases the circulation flow rate by 36.6%. Compared with powder, the carrier gas is the main factor that determines the circulating flow rate. Except for RH ladle bottom injection powder, other positions injection powder, the powder will reduce the circulation flow rate.