Water quality affects the flotation recovery of minerals and their separation. Mining-process waters become saturated with soluble salts after contact with minerals (oxidation and dissolution) during crushing, classification and flotation. Inorganic species, such as metal ions but also carbonate and sulphate ions, may have a positive or negative effect on mineral flotation. As sulphate ions are always found in high concentrations in process waters, their effects on the flotation of copper, molybdenum and zinc sulphides were investigated in single minerals and ores experiments with complementary mineral surface analysis and particle-bubble detachment studies. It was found that molybdenite flotation was more depressed than chalcopyrite flotation by the presence of sulphate ions in water as a result of increased surface oxidation which decreased particle-bubble attachment. Similar results were obtained in the flotation of two copper ores; however, the grade of chalcopyrite and molybdenite was much lower as a result of increased recovery of unwanted or gangue minerals (e.g., sphalerite, pyrite and quartz).

水质影响矿物的浮选回收及其分离。在压碎，分级和浮选过程中，与矿物质接触（氧化和溶解）后，采矿过程中的水就会被可溶性盐饱和。无机物，例如金属离子，还有碳酸盐和硫酸盐离子，可能对矿物浮选有正面或负面的影响。由于硫酸盐离子总是在生产用水中以高浓度存在，因此在单一矿物和矿石实验中，通过互补的矿物表面分析和气泡分离研究，研究了它们对铜，钼和锌硫化物浮选的影响。结果发现，由于表面氧化增加，从而减少了气泡的附着，钼矿的浮选比黄铜矿的浮选更受黄铜矿浮选的抑制。在两种铜矿石的浮选中获得了相似的结果。但是，由于不想要的或石矿物（如闪锌矿，黄铁矿和石英）的回收率提高，因此黄铜矿和辉钼矿的品位低得多。