Research On Comprehensive Recovery And Utilization Of Pyrite-rich Kaolin

Kaolin and pyrite are important raw materials,both with significant economic value,so it is of great significance to carry out the research on comprehensive utilization of kaolin-rich pyrite.Due to the charcateristic that kaolin is esay-to-slime,in the process of comprehensive recovery and utilization of pyrite-rich Kaolin,eliminating the effect of micro-fine and fine kaolin particles on the separation of pyrite by floation is the key factor to obtain acceptable pyrite product and achieve the purpose of refining kaolin.Through sedimentation test, this dissertation investigate the effect of different types of inorganic regulators on the dispersion behaviour and analyse the diversification mechanisms of kaolin by theory of flotation solution chemistry.On this basis, a separation test in a certain kaolin ore with high-pyrite was conducted and ways to improve further the quality of kaolin are explored.The dispersion of kaolin become better with the increase of pH and peak at the the pH value of9.94, with the suspension yield of66.98%.With the the increase of slurry pH, the concentration of anionic components among dissolved components rise,making it one of the reasons for better dispersion.Both sodium carbonate and sodium hexametaphosphate have the best dispersible effect in the concentration of9.52mg/L, with the suspension yield of55.40%and70.30%respectively. HCO3-,produced by hydrolysis of sodium carbonate and HPO42-in the sodium hexametaphosphate slurry are the main components to improve the dispersion of kaolin sepsrately. In the concentration of19.05mg/L, sodium silicate can achieve the best suspension yield of68.94%, but in the concentration range between9.52and14.28mg/L, the suspension yield decreased with the increase of concentration of sodium silicate. Sodium silicate acidified by sulfuric acid have better dispersible effect than sodium silicate acidified by hydrochloric acid, in the concentration of35.71mg/L.Three different concentrations of sodium silicate are acidified by sulfuric acid and higher concentration have better dispersible effect on kaolin.Three suspension yields appear to be minimum when pH change from7to8.In sodium silicate and acidified sodium silicate systems,before the pH value increasing to7,the improvement of dieperison is mainly attributed to the negatively charged H4Si04;when pH outnumber8, H3Si04" play the major role.The rich-pyrite kaolin ore, which contain kaolin(79.82%) and pyrit(18.14%), was processed by using acidizing sodium silicate as regulator, butyl xanthate as collector, and adopting the closed circuit flotation flowsheet of single-stage roughing, two-stage scavenging and two-stage cleaning; the results with the grade of S concentrate48.77%and the recovery of S87.30%were obtained.Purifying the kaolin desulfurated by flotation, both the content of iron and sulphur have a certain degree of reduction.