Research on Optimizing Traditional Zinc Hydrometallurgy Process with Pressure Leaching

The zinc concentrate was pressure leached with hot acid leaching solution from traditional zinc hydrometallurgy plant.The results show that the optimum conditions including leaching temperature of 130 ℃,ratio of liquid to solid of 14∶1,size of feed concentrate of 96%-50 μm,leaching time of 3 hours,oxygen partial pressure of 600 kPa,dosage of calcium lignosulfonate of 0.4%.As a result,the zinc leaching rate is more than 97%,iron content in leaching solution is less than 2 g/L,leaching solution can directly return to traditional neutral leaching process,and the sulfur is in the form of element sulfur in residue.This flow sheet is easy to combine with traditional zinc hydrometallurgy process.The pressure leaching process has the advantages of leaching zinc and iron removal simultaneously,efficient and environmentally friendly.