The Sherritt-Cominco Copper Process PART II: Pilot-Plant Operation

CIM Bulletin, Vol. 71, No. 790, 1978

P. Kawulka, Project Manager, Research and Development Division, Sherritt Gordon Mines Limited, Fort Saskatchewan, Alberta, C. R. Kirby, Senior Research Engineer, Technical Research Centre, Cominco Ltd., Trail, B.C., G. L. Bolton, Research Chemist, Research and Development Division, Sherritt Gordon Mines Limited, Fort Saskatchewan, Alberta

An integrated pilot plant for the development of the S-C Copper Process was constructed at Fort Saskatchewan in 1975 and operated in 1976. The pilot plant was designed to treat 9 tonnes per day of a pyritic copper concentrate. A demonstration run conducted during the last quarter of 1976 averaged 90% on-stream time, and confirmed that the process is operable as a stable and integrated unit. The paper describes the parameters and equipment developed for thermal activation of chalcopyrite copper concentrates to make them amenable for the dissolution of iron and zinc, and their subsequent separation and recovery. The resulting high-grade copper sulphide was leached with return electrolyte and oxygen to extract 98.5% of the copper into solution. The copper was electrowon at 650 amps per square metre from purified solution, to produce cathodes analyzing 0.1 ppm Se, 0.1 ppm Bi, 4 ppm Pb and 10 ppm S. The electrical conductivity was >101% IACS and the spring elongation value =2350 mm. Elemental sulphur and gangue are removed from leach residues to make a concentrate containing over 95% of the silver and gold and most of the unleached copper. Conventional construction materials such as stainless steel, titanium, Hastelloy, acid brick, rubber and plastics performed well. The containment inherent in hydrometallurgy provided high standards of hygiene and safety.
Keywords: S-C Process, Copper recovery, Thermal activation, Leaching, Jarosite precipitation, Activation leaching, Zinc recovery, Oxidation leaching, Purification, Electrowinning, Precious metals.