Research On Flocculation And Flotation Separation Behavior And Technology Of Micro-grained Artificial Zinc Sulfide Ore

Heavy metal waste pollution prevention and control is one of the focus areas in the study of environmental protection. Xiangjiang River basin is the most polluted area by the heavy metals in Hunan province. Exploring resource recycling technology is very important for heavy metal pollution reduction for Xiangjiang River basin. The object in this study is an artificial zinc sulfide ore that composed from lead and zinc wastewater treatment process produces and precipitation slag from a smelt group in Hunan. This paper discusses the cause of poor floatability of the artificial zinc sulfide ore through the comparative analysis of the microscopic properties of zinc sulfide ore and natural sphalerite. On this basis, this paper put forward the selective flocculation-flotation laboratory recovery process, and natural fractional crystallization-the microbial induced-election Continuous flotation process process. Achieved better test results, mainly as follows:(1) The hydrothermally synthesized artificial zinc sulfide ore particle size is very small, composed by the average particle diameter of30nm Synthesis ZnS crystal agglomeration. The distribution of particle size measured by a laser diffraction particle size analyzer is0.1-100μm, the distribution of natural sphalerite particle size is10～100μm. At the same time, ZnS and CaSO4wrapped inclusions each other, causing the artificial sulphide ore surface roughness, the contact angle with water small, the hydrophobic poor. Using conventional flotation methods, the zinc grade is only19.2%, enrichment ratio of1.37, the recovery rate of only30.5%. The efficient is poor.(2) Selective flocculation can effectively separate artificial sulphide ore from impurities. In acidic condition, with six article sodium phosphate as dispersing agent, glutinous rice starch as flocculating agent, the grade of zinc in sulfide has increased from14%to28%, recovery rate reached90%. It is a more simple and highly effective separation method. pH value is the most important factor for flocculation, the dosage of dispersant and flocculant followed. The most suitable pH is about5in this research.(3) Zinc grade of artificial sulfide ore is improved after of flocculation, and average particle size increases. XRD peaks of the artificial zinc sulfide ore become higher and sharp. The floatability is better. Zinc grade is49%, recovery rate stead at more than70%after once roughing floatation, twice cleaner floatation, three scavenging floatation.(4)Based on the technology of Zn/Ca natural fractional-crystallization, cyclone-classifier, microbial-induced on surface, nine classes of three days index of continuous flotation experiment prove the flotation process is stable and reliable. This has laid a good technology for industrial production.