The West Driefontein reclamation carbon-in-pulp plant; pilot plant testwork, design, commissioning and optimization

摘要

Driefontein Consolidated Limited has a proud history in the South African gold mining industry dating back to March 1945 with the formation of the West Driefontein Gold Mining Company. The reclamation gold plant at West Driefontein was originally built as a uranium recovery plant in 1970. With the collapse of the uranium oxide yellow cake market, the uranium plant was dosed in 1988 and successfully converted into a gold plant, recovering gold from repulped tailings dams.The West Driefontein Reclaim plant utilized milling, leaching, conventional rotary vacuum filtration and cementation to recover the gold at a rate of 200,000 dry tons per month. The No.1 tailings dam (at a head grade of 0,8 Au g/t) began to near the end of its life during 1996, and the next slimes dams to be treated, the No.2 tailings dam (at a lower head grade of 0.56 Au g/t) was found too marginal for reprocessing using the filtration technology.Alternate technologies were investigated, particularly the carbon-in-pulp (UP) plant based on the Anglo-American Corporation (AAC) pump-cell technology at the Vaal Reels Exploration and Mining Company's East gold plant which was operating profitably at lower head grades. The AAC pump-cell technology is based on the carousel mode of operation.The suitability of UP technology for the West Driefontein Reclaim plant was investigated using a pilot plant pump-cell supplied by Kemix.The data gathered were utilized in sizing a full scale AAC pump-cell plant This plant was motivated, built and commissioned on the 22nd of November 1996. Incorporating 6 eighty cubic metre AAC pump-cells. The West Driefontein Reclaim plant initially treated repulped slimes dam material. A subsequent change of feed material to current arisings (from the main gold plant) occurred in 1997 in order to convert mills for waste rock treatment Currently the reclaim plant treats a combination of current arisings and waste rock (milled at the reclaim site).The new UP plant replaced twenty A comparison between the costs was undertaken, as well as a pc plant to determine its flexibility in throughput, pulp density, gold input, UP, and the rate of carbon movement.