China Nonferrous Metallurgy

The biggest advantage of the zinc pressure oxidative leaching process is that the byproduct is solid sulfur instead of sulfuric acid, which can fundamentally solve the problems of slow sales of sulfuric acid and SO2 pollution caused by traditional processes. A zinc company utilized the zinc pressure oxidative leaching process in its production. When the sulfur recovery process was carried out in the initial stage, the sulfur recovery was low, with most of the sulfur having not been effectively recovered but brought to the tailings, resulting in the loss of sulfur and the difficulty of tailings treatment. Subsequently, the company systematically analyzed the pressure oxidative leaching process, and improved the sulfur conversion rate during the pressure oxidative leaching process by regulating the process parameters and increasing the particle size of the sulfur concentrate in the secondstage leaching residue, and improved the sulfur recovery rate in the flotation process by controlling the slurry concentration, slurry particle size, and air volume of the flotation cells, and increased the sulfur recovery rate in the subsequent procedures by standardizing the filtration operation and ensuring the temperature of the molten sulfur tank. After the company took such improvement measures, the total sulfur recovery rate increased from 45% to 71%. The specific methods can provide reference for other similar enterprises to improve their sulfur recovery rate.