The Classification And Floation Research Of Oxidative Pressure Zinc Leaching Residue

Base on existing machines and procedures of DanXia smelting plant, this paper is aiming at those problems such as high zinc content of leaching residues reaching up to 4%¹8%, waving residue particles, complex solution system and the various of toxic elements ( Zn²⁺,SO₄^2-,Fe²⁺,Fe³⁺,Ca²⁺,Mg²⁺,Cl^-,K⁺,Na⁺,Pb²⁺) merged with lignin, strong acid system make experimental machines unbearable etc. furthermore we have done researches of classification and flotation on Thickeners underflow with 32% of concentration. Improve separation effect of blende and elemental sulfur.Base on the preterit researchs, we first did research on gathering elemental sulfur and zinc through a 10°cone hydrocyclone which had been used to classify primary pulp and scrubbing residues, finally the result showed that scrubbing residues has a low classifying efficiency in the hydrocyclone, low recovery for sulfur and elemental sulfur of big particles have not been gathered in the grit. Blende tended to gather in the grit but can not reach 80% of recovery and the Zinc grade was low as well.Flotation research on primary pulp and scrubbing residues suggests that it can not obtain optimum result adopting direct flotation of primary pulp when the zinc content in the leaching residues is only 4.8%; using hot filtration-cleaning-pulp stirring method to treat leaching residues will efficiently get ride of the impact by liging and ion in the supernatant; the optimum primary flotation conditions were as follows: Butyl xanthate: 100g / t; 2 # oil: 50g / t; flotation time: 4min; inflated: 1.12L/min. By adopting the closed circuit flotation flowsheet of single-stage roughing, single-stage scavenging and single-stage cleaning,both zinc and sulfur is rich in concentrate. Zinc grade is 4.99% and sulfur grade is 85.10%, zinc and sulfur recoveries rate were 95.01% and 97.79%. The tailings of zinc grade and sulfur grade were 0.93% and 6.79%.Research on flotation separation and hydrocyclone classification of leaching residues showed that through the way"hot filtration—cleaning—pulp stirring"zinc and sulfur would be gathered together successfully.