PROCESSES AND COMPOSITIONS FOR WATER TREATMENT

摘要

The invention provides processes for the neutralisation of bauxite refinery residue by treatment with water containing sufficient calcium and magnesium ions to react with substantially all of the hydroxide, carbonate, fluoride a nd oxalate ions present in the bauxite refinery residue, and for a time sufficient for the treated refinery residue to exhibit a reaction pH of less than 10.5. The invention also provides processes and compositions for the treatment of water contaminated with dissolved inorganic substances such as acids and/or metal ions, the processes involving at least one step of adding to the water a bauxite refinery residue which has been treated with water containing sufficient calcium and magnesium ions to react with substantially all of the hydroxide, carbonate, fluoride and oxalate ions present in the bauxite refinery residue, and for a time sufficient for the treated refinery residue to exhibit residue to exhibit a reaction pH of less than 10.5.