浮选中矿选择性分级再磨浮选机理研究

安徽某铜矿随着井下的开拓延伸，铜品位有所下降，目前铜平均品位为0.62%左右，采用现场常用浮选药剂按铜硫混合浮选-铜硫分离、中矿循序返回流程试验，得到铜精矿品位21.47%、铜回收率85.52％的技术指标。采用中矿选择性分级再磨闭路大循环新工艺进行选矿试验，在铜精矿品位不低于现场指标的前提下，回收率提高到90.00％左右。综合应用Zeta电位分析与XRD测试手段，对中矿选择性分级再磨闭路大循环新工艺的机理进行研究并分析。试验结果表明，中矿选择性分级再磨闭路浮选工艺可以不断循序渐进地对有用矿物进行磨矿、分级、浮选，形成磨浮大循环，同时在闭路循环过程中改变原矿的表面性质，增大有用矿物的可浮性。

Study on the Mechanism of Selective Classification, Regrinding and Flotation of Flotation Middling

The copper grade the ore of an Anhui copper mine is somewhat reduced with the mining going deeper and averages about 0.62% at present.The copper concentrate produced in the on-site test adopting a process of copper-sulphur bulk flotation and middling recycling with conventional flotation reagents had a grade of 21.47% and a copper recovery of 85.52%.In the test adopting the new closed-circuit middling recycling process consisting of selective classification and regrinding, the copper recovery was raised to about 90%.Zeta potential analysis and XRD testing means were used in the analysis of the new process mechanism.The results indicate that the cycling of stepwise grinding, classification and flotation can change the surface properties of the valuable minerals and increase their floatability.