Abstract: The influences of three flocculants such as PFS, PAC and Alum on the treatment efficiency of waste water in Mengzi Lead-zinc Mine are contrasted.Based on this, PFS combining with coagulant polyacrylamide are selected to remove metal ions from wastewater by coagulating sedimentation.Then, the activated carbon is adopted to adsorb the organic pharmaceutical residues in wastewater, so as to make the metal ion content in wastewater and the chemical oxygen demand up to the discharge standard.The treated wastewater is recycled in the lead-zinc ore flotation tests of Mengzi lead-zinc ore, obtaining the close concentration index as that by fresh water.It is proved that the wastewater can totally be recycled to the production of mineral processing.

Key words: Dressing waste water, Coagulating sedimentation, Activated carbon adsorb, Waste water recycling