含铜氧化金矿氨氰选择性提金试验研究及工业应用

针对含铜氧化金矿采用氨氰选择性浸出提金,考察了分段加药制度、硫酸铵用量、矿石粒度等对金浸出率及浸出液铜金比的影响。结果表明:当硫酸铵用量8.00 kg/t,氰化钠用量0.60 kg/t,石灰用量5.00 kg/t,矿浆浓度40.00%,磨矿细度-0.074 mm粒级含量不低于95.00%时,平均金、铜浸出率分别为86.66%和1.16%。工业试验连续运行70 d,氰化尾渣金品位约0.55 g/t,金吸附率99%,金解吸率99.2%,电积回收率99.5%,金精炼回收率99.5%,金锭纯度99.99%,产品金达到国标Au-1标准。

Experimental Study on Selective Gold Extraction from Copper-Containing Gold Ore with Ammonia-Cyanide Leach System and Its Industrial Application

An experimental study was conducted for the selective gold extraction from Cu-containing gold ore using ammonia cyanide leach system. The effects of staged agent addition, ammonium sulfate dosage, ore grain size on the gold leaching rate, and the ratio of copper to gold in leaching solution were all investigated. Results show that with the addition of ammonium sulfate, sodium cyanide and lime at the amount of 8.00 kg/t, 0.60 kg/t and 5.00 kg/t, with pulp concentration at 40.00%, grinding fineness of -0.074 mm≥95.00%, gold and copper leaching rates reach 86.66% and 1.16% on average respectively. The industrial experiment with this process after 70 d successive operation resulted in the cyanide tailings grading 0.55 g/t Au, with gold adsorption rate at 99%, desorption rate for gold at 99.2%. The recovery rate by electrodeposition is 99.5%, the gold recovery rate from refining is 99.5%, and the gold ingot product has a purity up to 99.99%, meeting the national standard (Au-1).