FLOTATION METHOD OF METALLIC SALT PRECIPITATE AND GYPSUM

摘要

PURPOSE:To enable recovery of the precipitate through neutralization by slaked lime having good reactivity with a high grade and high yield by adding a dispersant to metal contg. water acidic with sulfuric acid then adding the slaked lime thereto, and subjecting the resulting slurry to flotation. CONSTITUTION:A dispersant such as sodium silicate is first added to metal contg. water acidic with sulfuric acid such as acidic mine waste water and factory waste water and thereafter the water is neutralized with slaked lime to form metallic salt precipitate and gypsum in respectively the dispersed state. Such slurry is subjected to flotation by using an anion capturing agent such as acidic alkyl sulfate and the gypsum is separated and recovered as floated ore and metallic salt precipitate as settled ore. The need for discarding the neutral precipitate in a dam, etc. as in the prior manner is eliminated and the method is extremely economical.