ZINC RECOVERY FROM ZINC FERRITE - BEARING INDUSTRIAL RESIDUES
Zinc residues normally contains large amount of iron oxide which is often associated with zinc oxide in the form of zinc ferrite (ZnO.Fe2O3). Zinc ferrite is one of the main technological barriers for zinc recovery in particular for hydrometallurgical processing routes. Current industrial practice for certain zinc-bearing residues such as acid leach residue from hydrometallurgical zinc production, and flue-dust from EAF steelmaking, is high temperature fuming process. The fuming process could only upgrade the residue as raw materials for primary zinc smelters. Various alternative processes have been developed, but most of them are inefficient for the treatment of zinc ferrite in the residue. In the present research, a combined processing route of hydrometallurgical and high temperature treatment was developed and tested in the laboratory scale. The final products are metallic zinc through electrowinning in alkaline solutions, and a clean iron concentrates for ironmaking. The zinc ferrite is converted to the alkaline soluble ZnO through alkaline roasting, which leads to high zinc recovery in the leaching and electrowinning stages. The processing flow sheet has been tested with industrial zinc residues, and it has the flexibility to handle various types of zinc residues in which zinc occurs either as free ZnO or bounded with hematite as zinc ferrite. The hydrometallurgical processing route is compared with the high temperature carbothermic reduction process.
Zinc residue zinc ferrite roasting alkaline electrowinning carbothermic reduction
Y. Yang D. Kemperman Y. Xiao
Delft University of Technology Mekelweg 2, 2628 CD Delft, the Netherlands
国际会议
北京
英文
1326-1334
2010-05-17（万方平台首次上网日期，不代表论文的发表时间）