电弧炉粉尘等温还原的动力学研究

Kinetics research of EAF dust reduction in isothermal condition

为使还原条件与实际电弧炉生产相接近，在等温条件下对电弧炉粉尘球团的还原过程动力学进行了研究。电弧炉粉尘与还原剂碳和粘接剂石灰均匀混合后制粒，经干燥后将球团置于恒定温度的加热炉中，利用电子称定时对球团重量进行检测。金属还原率的计算中，考虑了球团的失重、铅和锌在高温下挥发。经研究，电弧炉粉尘的还原分为二个阶段，还原初期由化学反应控制而还原后期由扩散控制，并建立了每一阶段的还原动力学方程，确定了有关的动力学参数表观活化能和频率因子。

The electric arc furnace (EAF) dust pellets were reduced in isothermal condition in order to make the reduction similar to the EAF production， and the kinetics of the reduction process is researched. The pellets were made with carbon as the reducing agent and dolomite as the binder. The electric furnace was used to heat the pellets, and the electrical balance was used to check the weight change of the pellets in the reduction process. The reduction degree was calculated according to the weight change of the pellets in the consideration of evaporation of moisture and the evolution of zinc and lead in high temperature. The results of the experiments show that the process is in two different steps. The reduction kinetics models are set up for each step, and the kinetics parameters such as activation energy and frequency factor are determined. The first step is controlled by chemical reaction and the second step is controlled by the diffusion.