Abstract

In this study, the flotation behaviors of gold and gold-associated sulfide minerals (pyrite and sphalerite) in a polymetallic sulfide gold ore were investigated using flotation kinetics parameters. It was found that high gold recovery (>90%) can be achieved by the selective flotation of pyrite and sphalerite. However, the sphalerite flotation results showed that sphalerite could not be separated from pyrite with a high selectivity (selectivity index∼1), because of insufficient depression of pyrite (with high alkaline medium and/or using a depressant). Even if more selective separation was achieved from the pyrite flotation (selectivity index∼5), 40% of sphalerite in the ore was transferred into the pyrite concentrate. In addition, the results of the collectorless tests indicated that more than 80% of the gold can be recovered, and higher selectivity indexes (up to 10) are achievable. Analysis of the particle size distribution of the collectorless flotation concentrate showed that the amount of −40 μm in the concentrate was 90%.

In conclusion, a gold concentrate containing low sulfur (10.8%) with a gold recovery of greater than 95% is achievable from a two-stage flow sheet (collectorless flotation as the rougher stage and pyrite flotation as the scavenger stage).

摘要

在这项研究中，使用浮选动力学参数研究了多金属硫化物金矿石中金和金伴生硫化物矿物（黄铁矿和闪锌矿）的浮选行为。发现黄铁矿和闪锌矿的选择性浮选可以实现高金回收率（>90%）。然而，闪锌矿浮选结果表明，由于黄铁矿的抑制不足（使用高碱性介质和/或使用抑制剂），闪锌矿无法以高选择性（选择性指数~1）从黄铁矿中分离出来。即使从黄铁矿浮选中实现了更高的选择性分离（选择性指数～5），矿石中 40% 的闪锌矿被转移到黄铁矿精矿中。此外，无收集器测试结果表明，80%以上的黄金可以回收，和更高的选择性指数（高达 10）是可以实现的。无捕收剂浮选精矿粒度分布分析表明，精矿中-40 μm的含量为90%。

总之，含低硫（10.8%）的金精矿和金回收率大于 95% 可通过两阶段流程（无捕收剂浮选作为粗略阶段，黄铁矿浮选作为清除剂阶段）实现。