Work is devoted to solution of the problem of processing dross obtained as a result of hot galvanizing of products, in particular, waste-free utilization of its oxidized component by chlorination firing using cheap chlorine-containing CaCl_2 and NH_4Cl reagents. Results of chlorination roasting of the dross oxidized component together with CaCl_2 and NH_4Cl at a 1000°C are presented. The effect of CaCl_2 and NH_4Cl consumption on lead and iron sublimation from the dross oxidized component in the form of chlorides is studied. It is found that use of CaCl_2 with a consumption equal to 6 of the weight of the oxidized component provides thorough purification of the starting material from Pb, Cu, Ni, Cd. Maximum reduction of the iron content is not possible. It is shown that use of NH_4Cl with a consumption of 15 of the weight of the oxidized component provides thorough removal of impurity metals and metallic zinc from the source material. It is found that with a firing temperature of 1000°C thorough sublimation of impurities is achieved, which ensures production of pure zinc oxide, suitable for use as a mineral additive in animal and bird feed. The content of metal impurities in the resulting zinc oxide is, wt.: Pb 0.02, Fe 0.08, Ni 0.02, Cu 0.008, Cd 0.001. Optimum firing parameters are established: T = 1000°C, duration 60 min, air flow 0.1 liter/min, CaCl_2 consumption 6, and NH_4Cl 15 of the weight of the oxidized component.
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