Numerical Simulation of Desulfurization Behavior in Ladle with Bottom Powder Injection

Abstract

A computation fluid dynamics–population balance model–simultaneous reaction model (CFD–PBM–SRM) coupled model was used to predict the reaction kinetic and desulfurization behavior in 80 ton ladle with bottom powder injection. The reaction rate and evolution of multi-components including Al, S, Si, Mn and Fe at the powder droplet–liquid steel interface, bubble–liquid steel interface, top slag–liquid steel interface and air–liquid steel interface were revealed. Then, the effects of different kinetic conditions on the desulfurization efficiency were investigated, and the importance of various mechanisms was discussed and clarified. The results show that at the lower powder injection rate, the desulfurization is mainly attributed to the joint effort of both powder–liquid steel reaction and top slag–liquid steel reaction which is the prevailing mechanism. At the higher powder injection rate, the powder particle–liquid steel and bubble–liquid steel interface reaction become more important and then predominate the desulfurization behavior. With the increase of gas flow rate, the total desulfurization ratio gradually decreases, and with the increasing of powder injection rate, the total desulfurization ratio increases.