The Mixing Characteristics of Powder Injected through Top Lance in RH Degasser

Abstract

With the increasing demand for high quality steel, various secondary refining techniques have been developed in the past decades. RH powder top blowing process (RH-PTB) is practiced in industry to decrease the impurity content of steel in a more economical way. In the present work, based on similarity theory, RH powder top blowing process was simulated by water model, and the effects of operating parameters on mixing time were investigated. The results show that the injected powder had a negligible effect on mixing time in RH-PTB, and the mixing time increases with top lance gas flowrate and decreases with lifting gas flowrate of up-leg. It was found that the mixing time was no longer decreasing as the lifting gas flowrate was over 15 L/min. Moreover, the height of top lance has some effect on mixing time in the reactor, and it should be adjusted to specific circumstances for purposes.