Pyrometallurgical brass production

摘要

Waste materials containing significant quantities of zinc oxide are mixed with carbon and a sufficient amount of copper to set the overall Zn/Cu weight ratio to a selected value below 0.66. The mixture is loaded into the top of a shaft furnace having a lower region which is heated. Hot gas rising from lower regions of the shaft furnace preheats the mixture as it descends. Rising zinc vapor is prevented from escaping the furnace because it condenses in the relatively cool preheated mixture descending down the furnace. As the mixture descends, it enters a brass production zone where zinc vapor alloys with the copper in the mixture. Further descent brings the mixture to a zinc reduction zone where the temperature is above 950 DEG C and where ZnO is reduced by carbon or carbon monoxide to produce a zinc vapor which rises coutercurrently to the charge. Molten brass and some slag is removed from a brass reservoir which forms in the bottom of the furnace.