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Zinc metallurgy and project

The technology of Zinc hydrometallurgy is the main form of current technology of Zinc smelting process. The Zinc sulfide concentrate is firstly roasted and desulfurized into calcines which is then leached to extract the Zinc into the solution, reacting with spent electrolyte to produce soluble sulfate and elemental S.  The S in concentrate is oxidized into SO2 in off-gas which will be converted into acid by conversion and absorption process.

• Traditional leaching process 

Zn concentrate is roasted, and then calcines go through a neutral leaching circuit followed by low acid leaching circuit. The neutral leaching supernatant is purified before sent for electrowinning process. 

• Oxygen pressure leaching process

During pressure leaching process, the Zinc sulfide in concentrate will be turned into Zinc Sulfate conditioned within the certain conditions such as a proper temperature, acid amount and oxygen pressure. Then the Zinc Sulfate solution will be precipitated and applied with electrowinning to produce Zinc; The Sulphur in concentrate is turned into elemental S in residue which can be further purified as a product for further sale. 
The main process consists with pressure leaching, flashing, adjusting and elemental recovery. 

•  Features of Oxygen pressure leaching

No need to provide with the roasting process, environmental friendly;
Wide flexibility of raw materials;
environmental friendly;
High recovery rate of other valuable elements 
Elemental S are easier to transfer, storage and sale;
Pressure leaching action takes place in a closed container with less steam consumption;
High recovery rate of other valuable elements 


 • Zinc electrowinning


• We can provide the complete equipment sets including

Automatic stripper machine
Automatic Cathode Brushing
Machine+Automatic Multifunctional
Automatic Zinc Cathode Sheet Conveyor Complete Zinc Melting and Casting machine Anode Car and Anode cleaning and Flattening System

• All of which have been industrialized with the performance in line with international standards.