Combined beneficiation process for wolframite and cassiterite from tungsten tailings: Mechanism and case study

Abstract

Owing to the lack of effective beneficiation technologies, valuable wolframite and cassiterite resources are lost in the tailings of tungsten–tin polymetallic mines. For Shizhuyuan polymetallic mine, the recovery efficiencies of wolframite and cassiterite were significantly lower than those of scheelite using existing process. In this study, the underlying causes were investigated based on the flotation kinetics, surface hydration characteristics of the three target minerals, and the adsorption behavior of the collector. To enhance the comprehensive recovery of wolframite and cassiterite from the tailings, a novel double-ligand collector, Pb–BHA–SDBS (lead–benzohydroxamic acid–sodium dodecyl benzene sulfonate), was designed and successfully implemented in the Shizhuyuan polymetallic mine. Accordingly, a novel beneficiation process combining flotation and gravity separation was developed, yielding an additional low-grade W–Sn mixed concentrate. This process not only generates economic value for enterprises but also provides a reference for the comprehensive utilization of tungsten–tin polymetallic ore in the Nanling metallogenic belt of China.

Keywords

Cassiterite / Wolframite / Tungsten tailings / Sodium dodecyl benzene sulfonate / New ligand / Combined beneficiation

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