Mill performance at Sar cheshmeh porphyry copper mine with special reference to the distribution of gold in the mill products

摘要

The Sar Cheshmeh porphyry copper deposit locatedin southern central Iran, with the sulphide ore reserves of about1.22 billion tons averaging 0.69 percent Cu and 0.027 percent Mo,ranks with the great copper deposits of the world. Minor amountsof gold, silver, and selenium are also present in the ore.The current operation at Sar Cheshmeh includes open-pit mining,milling, smelting, and copper refinery, with a rated production of158,000 t/y of cathode copper. Concentrator flowsheet consists ofcrushing, grinding, hulk flotation of copper sulphides andmolybdenite, differential flotation of molybdenite, and dewateringcircuits, capable of processing 43,000 t/d of about 1 percent Cuore, and producing approximately 1,300 t/d of 30 percent copperconcentrate containing 0.8-1.2 ppm Au and 30-40 ppm Ag, as wellas a molybdenum concentrate of 55 percent Mo.In this study a comprehensive sampling of the concentrator plantwas carried out and over 130 samples of mill products wereanalyzed for 48 elements. The metallurgical balances of copperand gold during the sampling periods show that, in compare with80 percent copper recovery, about 44 percent of the gold isrecovered as the by-product into the copper concentrate, and theremaining is lost to the tailing.In this manuscript the geology and current plant practice at SarCheshmeh are briefly described, and an assessment ofmetallurgical performance of the concentrator plant at varioustime intervals with special reference to the behavior of gold in themill products are presented.