抢马金矿工艺矿物学特征及对提金工艺的影响

所研究矿石中的金以自然金类矿物形式存在。其嵌连形式有裂隙金粒、粒阁金粒和包裹金粒。裂隙金粒和粒间金粒占总金粒的90％以上。粒度大于0.3mm占22％,大于0.074mm占65.9％,重选或混汞提前回收这部分金是必要的。自然金颗粒形状有片状、棒状和不规则状。重选不能充分回收片状金粒,这部分金需要浮选法回收。金粒表面覆膜不算太严重,有3.3％的金粒表面被覆盖,28.5％的金粒失去光泽。电子探针面扫描分析表明,覆膜的主要成分是银和硫。有覆膜的金粒需要重选回收,失去光泽的金粒浮游速度和氰化速度会变慢。根据研究结果,对矿石可处理性进行了评价。重—浮选工艺较为适合本矿石的性质。

PROCESS MINERALOGICAL CHARACTERISTICS OF THE QIANGMA GOLD ORE AND THEIR INFLUENCE ON EXTRACTION PROCESS

The gold and silver contents of the tested ore are 10.7g/t and 14.7g/t respectively, and copper is 0.36% and lead 0.24% on average. The principalconstituents of the ore are pyrite (1.60%) , chalcopyrite (0.82%) , galena (0.14%) , siderite (1.94%) and quartz (94.99%) . Gold in the ore is in occurrence of native gold. After grinding to less than 0,1mm, about 17% of gold is still locked in the matrix. Gold in sulphides is 14,17% of total gold in,.the ore Basea-on the above. data, it is suggested that the highest recovery of gold is 96.93% with gravittaion-floatation process. Gold content in the final tailings is about 0.33g/t, and its reasonable loss rate of metal is 3.07%. There are three types of interlocking rala-tionsthip between gold and matrix, namely, gold in fracture, gold along grain boundaries and included gold. Gold in the fracture and gold along grain boundaiies occupy above 90% of total gold grains and are liberated easily in grinding stage. The microscopic examination results show that more than 90% of gold in 60%-200 mesh feed has been liberated, 22% and 65.9% of gold are more than 0.3mm and 0.074mm is size respectively. So grav itational separation and amalgamation must be used to recovery them. Gold grains are of three different forms, schistose, bar and irregular grains. Their interrelationship rate is 12.6%, 24.6% and 62.8% by weight respectively. Schistose grams cannot be recovered with gravitational process. To exiract it floatation is necessary. Coating of gold grains is net srong. the coated and iuste lost grains are 3.8% and 28.5% of total gold grains in weight respectively. EPM Raster Scanning data show the coating of the grains is mainly composed of silver and sulphur. The coated grains need gravitation to be recovered. Floatation and cyanide rates of the luster-lost grains will become slow According to the above results, the ore amenability has been evaluated, and the treatment of the ore with gravitation-floatation flowsheet is considered as reasonable.