Chemistry of lime roasting process for complex sulfided concentrate was described briefly, the chemical phases of gold, silver and carbonaceous substances in the concentrate were also in vestigated, and the influences of roasting temperature, time and stoichiometic ratio of hydrated lime on sulfur retention and silver extraction of the calcine were studied finally. Under the optimized conditions, gold-silver extractions exceeded 93% and 83%, respectively.

测定了半合成的不同成分的FeO-MgO-SiO2系炉渣粘度。在w（MgO）为6%～10%，w（Fe）/w（SiO2）为1.1～1.4，温度为1200～1500℃时，炉渣粘度随w（MgO）和w（Fe）/w（SiO2）的提高而增大；在w（MgO）<6%时，冶炼温度控制在1300℃即能保证顺利生产；当w（MgO）>10%时，镍冶炼炉渣的温度应控制在1360℃以上；在MgO含量较高时，可通过降低w（Fe）/w（SiO2）得到粘度较低的炉渣。金川闪速炉炉渣的合理w（Fe）/w（SiO2）为1.2左右。

Kinetic studies of the electric arc furnace (EAF) dust reduction process have been carried out under non-isothermal temperature condition. EAF dust pellets were made with carbon as the reducing agent and dolomite as the binder. A Thermo-Gravimetric Analyzer (TGA) was used to determine the mass loss of pellets, which were heated at an average rate of 40K/min up to 1500℃. The reduction degree was calculated by consideration of the pellet mass loss, evaporation of moisture, dust, zinc and lead at high temperature. The reduction process of EAF dust was divided into three steps related to the change in temperature and time. The non-isothermal reduction kinetics equations were set up to describe every step. The kinetics parameters such as apparent activation energies and frequency factors were established at the same time. It was found that the first step is chemically controlled, the second step is diffusion-controlled and the third step is strongly dependent on the initial content of carbon in the pellet. CrO can be reduced only in the last step by high temperature and high initial carbon content.