The direct reuse of weathered tungsten-ore beneficiation wastewater (WTBW) in tungsten-flotation system seriously deteriorates the flotation index of tungsten because of its high content of suspended solids (SS). In the present study, an innovative technology using calcium chloride (CaCl₂) to remove SS from WTBW was established based on the theory of electroneutralization and chemical precipitation. A series of laboratory tests was performed to determine the optimal conditions for SS removal from WTBW. Species-distribution calculation, zeta potential, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy were used to analyze the underlying mechanism. Results showed that the content of SS in WTBW decreased from $\text{25.16}\times {\text{10}}^{\text{3}}$ mg/L to 22.56 mg/L after CaCl₂ treatment. A concentrate with tungsten grade and recovery of 1.93% and 74.81%, respectively, was obtained by reusing the treated wastewater in the tungsten-flotation system. Compared with untreated wastewater, the tungsten grade and recovery of concentrate increased by 0.45% and 12.20%, respectively. Moreover, the Ca²⁺ supplied by CaCl₂ can neutralize the negative charge on SS surface and further react with CO₃^2– and SiO₃^2– in solution to form CaCO_3(S) and CaSiO_3(S), which explained why CaCl₂ can promote the aggregation and sedimentation of SS.

在钨浮选系统中直接回用风化钨矿选矿废水（WTBW），由于其悬浮物（SS）含量高，严重恶化了钨的浮选指数。在本研究中，基于电中和和化学沉淀的理论，建立了使用氯化钙 (CaCl ₂ ) 从 WTBW 中去除 SS的创新技术。进行了一系列实验室测试以确定从 WTBW 中去除 SS 的最佳条件。物种分布计算、zeta 电位、X 射线衍射、傅里叶变换红外光谱和扫描电子显微镜结合能量色散 X 射线光谱被用来分析潜在的机制。结果表明，WTBW中SS的含量从$\text{25.16}\times {\text{10}}^{\text{3}}$CaCl ₂处理后的mg/L至22.56mg/L 。通过在钨浮选系统中回用处理后的废水，分别获得了钨品位和回收率分别为 1.93% 和 74.81% 的精矿。与未经处理的废水相比，钨品位和精矿回收率分别提高了0.45%和12.20%。此外，CaCl ₂提供的 Ca ²⁺可以中和 SS 表面的负电荷，并进一步与溶液中的CO ₃ ^2-和 SiO ₃ ^2-反应生成CaCO _3(S)和 CaSiO _3(S)，这解释了为什么CaCl ₂可以促进SS的聚集和沉降。