Method for oxidative roasting of sulfide zinc concentrates in an air oxygen stream in fluidized bed furnaces

Abstract

An increase in the oxygen content in the blast to a concentration of 26-28% during the firing of zinc concentrates in the KS furnaces leads to a decrease in the formation of undesirable compounds of ferrites and zinc silicates, increases the degree of desulfurization, and shortens the firing time. At the same time, it becomes possible to load concentrate with high humidity into the furnace, which will save costs for drying the raw materials. Ultimately, it leads to an increase in the complexity of raw materials, increasing the profitability of production and making the products competitive in the world market. The article is considered questions of increased efficiency of processing collective zinc concentrates without their preliminary selective division. Our developments on the processing of collective zinc concentrates are directed to that in the maximum degree to receive sulfates of zinc transferring zinc to the solution. Thermodynamic calculations show that the formation of sulfates most intensively precedes in the range of 1000-1100 °C. It is offered to carry out roasting of a collective concentrate to furnaces of the boiling layer in the gas environment.