Chemical Treatment in mining refers to the deliberate application of chemical substances to ore, water, tailings, or process streams to achieve specific metallurgical, environmental, or engineering outcomes — including the dissolution of valuable metals, adjustment of physicochemical conditions, precipitation of contaminants, stabilization of waste materials, or improvement of separation processes. Chemical treatment is pervasive across all stages of bauxite, iron ore, gold, and diamond mining — from ore preparation through beneficiation, refining, and post-operational rehabilitation. In bauxite processing, chemical treatment begins with the addition of lime to control silica reactions and scale deposition, and flocculants to improve settling rates of red mud in thickeners. In the Bayer Process liquor circuit, organic impurity control involves chemical treatment with lime and activated carbon to remove sodium oxalate and other organics that inhibit precipitation. In gold mining, chemical treatment of ore using sodium cyanide (NaCN) with lime as a pH modifier is the primary gold dissolution method. Pre-treatment of refractory gold ores using pressure oxidation (POX), biological oxidation (BIOX), or roasting chemically alters the sulphide mineral matrix to liberate occluded gold before cyanidation. In iron ore processing, chemical treatment with depressants (such as cornstarch or dextrin), collectors (such as fatty acids), and frothers in flotation circuits selectively separates iron minerals from silica gangue. Water treatment at mine sites involves chemical dosing with coagulants, flocculants, lime, and chlorine to meet discharge standards for pH, turbidity, suspended solids, heavy metals, cyanide, and nitrogen species. Diamond processing uses chemical treatment for organic destruction and pH adjustment in effluent management.
