摘要
卡林型金矿富含有机质,金主要呈显微-超显微分散状态存在,利用工艺矿物学参数自动检测分析仪(MLA)及传统化学方法只能大致判断矿石中金的赋存趋势,无法对其赋存状态准确定量。本文利用MLA仪器系统分析贵州回龙卡林型金矿,测得矿石中金主要以显微-超显微状态包裹于黄铁矿和毒砂中,少量被脉石等其他矿石包裹;黄铁矿约66%完全解离,而毒砂仅30%完全解离,载金矿物与其他矿物连生或者被包裹,将不利于硫化物包裹金的浸出。结合回龙金矿石中金的赋存特征和富含有机质的特点,对传统的物相分析流程进行改进,调整了硫化物包裹金和碳酸盐包裹金的浸出顺序,提出裸露金—碳酸盐包裹金—硫化物包裹金—硅酸盐包裹金的浸出流程,在裸露金及碳酸盐包裹金浸出时加入活性炭,利用竞争吸附抑制矿石中有机炭对金的吸附,降低有机炭对分相的影响。对比试验结果表明,采用改进的方法,有机炭含量在1%左右的金矿石分相时加入活性炭对各相测定值的影响不大;先浸出碳酸盐包裹金,再测定硫化物包裹金,各相的测定数据更加准确。改进的方法(加活性炭)用于测定回龙金矿中裸露金和碳酸盐、硫化物、硅酸盐包裹金,含量分别为1.25%、84.17%、11.46%和3.13%,与选矿试验结果相一致,表明该法适合应用于卡林型金矿中金的赋存状态分析。
Gold exists in the form of micro-super micro dispersed states in Carlin-type gold ores, which is in the form of rich organic matter. The gold occurrence state cannot be analyzed accurately or at best, can be roughly estimated by using the Mineral Liberation Analyzer （MLA） and the traditional chemistry method. In this study, carlin-type gold ore in Guizhou Huilong was analyzed systematically using MLA, and the results show that microsuper micro gold was mainly embedded in pyrite and arsenopyrite, and less was embedded in gangue minerals and other minerals. The separation degree of pyrite and arsenopyrite were 66% and 30% in minerals, respectively. As gold-bearing minerals are attached or embedded in other minerals, the separation of gold-bearing sulfides （GBS） is more difficult. The leaching orders regarding free gold （FG）, gold-bearing carbonates （GBC）, gold-bearing sulfides （GBS） and silicates （GBSi） were sequenced on the basis of the tradition method, gold occurrence state and high content of organic matter characteristics of Guizhou Huilong gold ore. Furthermore, according to the high content of organic matter in this deposit, the activated carbon was added in the process of leaching FG and GBC to restrain the adsorption to gold by organic carbon. The comparative studies between traditional methods （TM） and modified methods （MM） show that there is only a small effect on the detected value after adding activated carbon into the gold ores which contain about 1% of organic carbon. In MM, gold-bearing carbonates were leached prior to gold-bearing sulfides ; results of every phase data were more accurate than those of TM. Along with the addition of activated carbon in MM, the contents of FG, GBS, GBC, GBSi in Guizhou Huilong gold ore were 1.25% , 84. 17% , 11.46% and 3. 13%, respectively, which was consistent with the results of processing experiments. This indicates that MM can be applied to analyze precisely the occurrence states of gold in carlin-type gold ores.
出处
《岩矿测试》
CAS
CSCD
北大核心
2013年第3期474-482,共9页
Rock and Mineral Analysis
基金
国家重点基础研究发展计划(973计划)项目(2012CB724202)
关键词
卡林型金矿石
碘-碘化钾
物相分析
活性炭
Carlin-type gold ore
iodine-potassium iodine
phase analysis
activated carbon
