老挝某金矿重选-重选尾矿氰化浸金实验

为预先回收老挝某金矿石中的中粗粒金,开展了重选-重选尾矿氰化浸金实验,结果表明,在磨矿细度-0.074 mm粒级占75%、重力值为60G、重选流态化水流量3.6 L/min、给料速度500 g/min条件下,尼尔森重选获得的金精矿品位为15 812.50 g/t,回收率达到21.94%;在磨矿细度-0.074 mm粒级占90%、矿浆浓度40%、CaO用量3 000 g/t、预处理2 h、NaCN用量800 g/t、浸出时间32 h条件下对重选尾矿进行氰化浸金,金浸出率达到74.24%。两种工艺联合最终获得金总回收率96.18%。

Experiment of Gravity Concentration-Cyanide Gold Leaching Process for Gold Ore in Laos

In order to pre-recover medium- and coarse-sized gold from a gold ore in Laos, a process of gravity concentration followed by cyanide gold leaching from the gravity concentration tailings was adopted. It is found that an experiment by using Knelson concentrator with grinding fineness of -0.074 mm 75%, gravity value at 60G, fluidized water flow rate of 3.6 L/min and feed speed at 500 g/min, resulted in 21.94% Au recovery into the concentrate grading 15 812.50 g/t Au. Then, the obtained tailings at a grind size of -0.074 mm 90% were leached by gold cyanidation for 32 h with slurry concentration of 40%, CaO dosage of 3 000 g/t, pretreatment for 2 h, NaCN dosage of 800 g/t, leading to the gold leaching rate at 74.24%. Finally, a total Au recovery of 96.18% was obtained by the combination of two processes.