某高硫含砷低品位金精矿选矿工艺研究

Study on the beneficiation process of a high-sulfurand arsenic-bearing low-grade gold concentrate

为提高某高硫含砷低品位难处理金精矿选别指标,分别采用尼尔森离心重选和高效旋流器分级工艺进行金精矿分选试验研究。试验结果表明:在保障金精矿冶炼净返系数等级的基础上,采用试验条件为重力倍数60G、反冲洗水量4 L/min、给矿速度400 g/min的尼尔森离心重选工艺,可获得金品位为30.97 g/t,金回收率为19.97%的重选精矿;采用试验条件为矿浆浓度20%、沉砂口直径22 mm的高效旋流器分级工艺,可获得金品位为26.02 g/t,金回收率为12.50%的溢流。尼尔森离心重选、高效旋流器分级工艺可使最终精矿产品的金回收率分别提高1.6%~1.9%和0.7%~1.0%。考虑到尼尔森离心重选工艺成熟工艺少、后期投资高,故推荐高效旋流器分级工艺进行该金精矿分选试验,以提高该金精矿利用价值。

In order to improve the separation indicators of a high-sulfur and arsenic-bearing low-grade refractory gold concentrate,the experiments of Nelson centifugal gravity separation and hydrocyclone classification processes were conducted.The experimental results showed that based on ensuring the net recovery factor grade of the gold concentrate smelting,a gold concentrate with a grade of 30.97 g/t and a gold recovery of 19.97%could be obtained under the experimental conditions of a gravity multiplier of 60 G,back flush water volume of 4 L/min,and a feeding rate of 400 g/min in the Nelson centrifugal gravity separation process.Likewise,a high-grade gold concentrate with a grade of 26.02 g/t and a gold recovery of 12.50%could be obtained under the experimental conditions of a pulp concentration of 20%and an underflow diameter of 22 mm in the high-efficiency hydrocyclone classification process.Nelson centrifugal gravity separation and high-efficiency hydrocyclone classification processes can improve the gold recovery rates of the final concentrate products by 1.6%-1.9%and 0.7%-1.0%,respec tively.Considering the less mature technology and higher investment in the Nelson centrifugal gravity separation process,it is recommended to carry out the beneficiation experiment using the high-efficiency hydrocyclone classifica tion process to enhance the utilization value of the gold concentrate.