甘肃某氧化型金矿石选冶技术研究

Research on Mineral Processing-metallurgy Combination Technology for an Oxidized Gold Ore in Gansu

甘肃某氧化型金矿石金含量为2.25 g/t,伴生银可综合回收。金主要以独立金矿物形式存在,大部分被载金脉石矿物石英所包裹,少部分以微细粒的形式嵌布在黄铁矿、磁黄铁矿、闪锌矿、黄铜矿和方铅矿等矿物的裂隙中。为高效开发利用该矿石资源,对其进行了选冶联合试验研究。结果表明:在磨矿细度为-0.074 mm占73.00%条件下,经1粗1精2扫浮选、浮选尾矿重选的闭路流程可获得金品位74.2 g/t、回收率91.28%的混合金精矿。混合金精矿经石灰预处理后,经氰化钠浸出,获得了金浸出率为96.52%、金总回收率为88.10%的指标。试验结果对同类型金矿石的选矿回收具有借鉴意义。

The oxidized gold ore in Gansu contains 2. 25 g / t gold and associated silver can be comprehensively recovered. Gold mainly exists in form of independent mineral,most gold ore were wrapped in gangue minerals,like quartz,few others was inlayed in the cracks of pyrite,magnetic pyrite,sphalerite,chalcopyrite and galena with the form of fine particles. In order to high efficiently utilize the resource,mineral processing-metallurgy combination experimental research was carried out based on process mineralogy. The results indicate that the mixed concentration with gold grade and recovery of 74. 2 g / t and 91. 28%can be obtained at the grinding fineness of 73. 00% passing 0. 074 mm,via one roughing-one cleaning-two scavenging floatation operation,and gravity separation for floatation tailings. Gold leaching rate of 96. 52% and total recovery of 88. 10% was obtained by lime pretreatment with mixed concentrate and then leaching by sodium cyanide. The experimental results can provide technology basis for beneficiation of the ore in same type.