摘要
本文介绍了堆浸提金原理和在实验室进行金矿石堆浸可行性研究的方法.以我国辽宁猫岭金矿、四川茶铺子金矿和福建紫金山金矿为研究对象,研究了矿石粒度、氰化钠溶液浓度、浸出时间等因素对金浸出率的影响,从而确定堆浸提金最佳工艺条件.通过对上述三类矿石性质及堆浸性能的比较,认为矿石的物质组成和金的嵌布特性对金的浸出率影响较大.
The authors summarize the present situation of heap leaching method for gold extraction in China and discuss the principle and the feasibility of the method.
As objectives of the research project, Maoling gold deposit in Liaoning, Chapuzi gold deposit in Sichuan and Zijinshan gold deposit in Fujian were studied in their mineral composition, gold occurrence, the feasibility of heap leaching, and the influence of ore size, sodium cyanide concentration and leaching time on the extraction rate of gold.On the basis of the study, the technical conditions for the three types of ore were determined with good indexes.
Maoling gold deposit is one of As-bearing sulphide type, with low-grade ores, For ores of 2.9g/ t gold, 10mm in size, w (NaCN) = 0.12%, and 30days' leaching time, the extraction rate is up to 66.90%.
Chapuzi gold deposit is a disseminated carbonate-type and suboxidized deposit with low-grade (1.6g/t) gold.When ores size is 20mm, w (NaCN) =0.7%, and leaching time is 30days, the extraction rate will be 73.27%.
Zijinshan gold deposit belongs to Fe- bearing siliceous oxidized type with poor ores.The grade of gold is 1.49g/t. For ores of 20mm in size, w (NaCN) =0.07%, and 20 days of leaching, the extraction rate may be 95.93%.
The performence of heap leaching for the three types of ores are also compared. The properties of ores are believed to affect the extraction rate greatly. The more cyanide-consuming material the ore contains, the more difficult extraction for gold is. The As and S content, and the oxidizing and weathering degree have a great effect on the extraction result. And, the particle xize and embedding pattern are direct factors affecting the extraction of gold.
