Sustainable Mining and Metallurgy

A lead smelting enterprise in China used the combination of primary lead and recycled lead to realize the recovery of lead and zinc resources and the recycling of waste acid. The production process of nano-zinc oxide included leaching process, primary purification process, secondary purification process, synthesis process and baking process. In the production process, it was found that the recovery rate of nano-zinc oxide was low, resulting in high production cost. By optimizing the acid leaching times of the production process, reducing the zinc content of the acid leaching residue, comprehensively utilizing the zinc and cadmium metals in the secondary purification residue, recycling the synthetic tail liquor, and changing the NPP static baking furnace equipment to the dynamic baking furnace to improve the dust collection efficiency, the recovery rate of nano-zinc oxide was increased from 87.5% to 90.5%, and the economic benefit was good.