Teck Cominco have developed a new, low-cost process for the direct extraction of zinc metal from sulphide ores. The process is called HydroZinc ™ and they currently have patents pending on the technology.
The HydroZinc process involves bioloeaching of ore heaps with naturally occurring bacteria. This is followed by neutralisation, solvent extraction and electrowinning.
Teck Cominco have been developing the process for over four years and had a 1 tonner per day pilot plant in operation between October 2000 and December 2002.
One of the advantages of the HydroZinc process is that it does not require the grinding and flotation of the ore. Furthermore, it is claimed to be environmentally friendly and free of sulfur dioxide handling and emissions.
The newly developed process is suited to a range of ores and has a direct operating cost of 20 cents per pound.