Accumulation of difficult-to-remove impurities of alkali and alkaline-earth metals in circulating solutions during the existing zinc production process
摘要
The hydrometallurgical cycle of the existing zinc core production process at the Chelyabinsk Zinc Plant (CZP), JSC involves a constant circulation of 19,000 to 22,000 m3 of solution, containing the key component (zinc sulfate) and a number of impurities, the presence of which affects the efficiency and techno-economic performance of the production to a varying degree. The sources of such impurities include zinc-containing process materials and reagents used in zinc production. The removal of impurities from the circulating solution is carried out both during its preparation for the core production process (electrowinning), and during the performance of certain technological operations, preparation of raw materials, and processing of intermediate products. A number of impurities, such as salts of alkali and alkaline-earth metals, are classified as those accumulating in the circulating solution due to the fact that the existing production process at the CZP, JSC does not allow for their selective removal. Therefore, one of the main directions of the research activities at the CZP, JSC is the development of a fundamentally new technology for removing accumulating difficult-to-remove impurities with minimal zinc losses, and obtaining residual products that could find wide industrial application.