Application of Oxygen-enriched Side-blowing Technology in Treating Zinc Leaching Residue in China

Abstract

Zinc hydrometallurgy is the main process of zinc smelting in the world. The leaching residue produced by different hydrometallurgical processes have different components, but they contain valuable metals such as zinc, silver, gold, indium and germanium, and heavy metals such as lead, cadmium and arsenic. In China, leaching residue is defined as hazardous waste, which requires harmless treatment and recovery of valuable metals. At present, China’s main zinc leaching residue treatment technologies include Welz kiln, fuming furnace and Top-submerged lance Smelting furnace. These technologies have been applied for many years and are mature and reliable, but they need further improvement in energy conservation and environmental protection. In recent years, with the continuous progress of China’s smelting technology, the oxygen-enriched side-blowing technology has been successfully applied to the treatment of zinc leaching residue, mainly including the Side-submerged combustion smelting technology of China ENFI and the Vanukov side-blowing technology. At present, the above two side blowing technologies have been put into industrial practice in many zinc smelters in China, which are characterized by low energy consumption, high recovery rate of valuable metals and high sulfur recovery rate. This paper introduces the application of the above two side blowing technologies in China’s zinc smelters, and compares them from furnace structure, production operation, and technical indicators. Oxygen-enriched side-blowing technology will become the mainstream treatment process of zinc residue in China and even in the world in the future.