Experimental Research On Mineral Processing Of Low Grade Refractory Kyanite In JiangSu

As high-grade refractories raw material, kyanite is widely used and the market demand is increasingly greater. But the relatively high-quality and low impurity content kyanite has consumed, and the development and utilization of low grade and high harmful components content of kyanite is imperative.The low grade kyanite in JiangSu Shu Yang is complicated, main chemical composition is SiO271.68%,Al2O320.98%,TFe2O32.78%,TiO21.35%, the content of iron and titanium impurity is high, and exist in the form of hematite-limonite,ilmenite,rutile and andradite. The mineral weathering seriously and has variety of gangue minerals, which commensal relation is intimate. The grain size is inhomogeneous and dyed by iron and titanium, these gangues exist in the form of inclusions, which makes it difficult to separate kyanite from gangue minerals. This is the key points and difficult points of this mineral separation.The result of investigation on mineral processing technology show that the suitable grinding way is ball-milling and suitable fineness is-0.074mm 65.28%. Desliming has a great influence on kyanite, especially acid process, the suitable lower limit particle size for desliming is 20μm. Magnetic separation process may remove most of the iron-bearing minerals, and the iron removal rate is 84.64%. The optimum condition for magnetic separation is magnetic field conditions LOT, velocity 3.5 cm/s, pulse 1000r/min.The optimum collecter is sodium oleate and decyl in alkaline medium (pH9-9.5), and sodium petroleum sulfonate in acid medium (pH3-3.5). However, it is difficult to obtain eligible kyanite concentrate in alkaline medium using sodium oleate and decyl. In acid mediun, using sodium petroleum sulfonate may easier to obtain high recovery and high grade kyanite concentrate, but the content of TiO2 is overproof. It has explore three process to remove impurity. The result shows that it is difficult to obtain eligible concentrate when using alkaline-acid process. Magnetic-flotation-reelect alignment process can be obtained, but the process complex and recovery lower. While, ramified flotation can meet the qualification of LJ-55.In ramified flotation process,+0.045mm can obtain eligible kyanite concentrate, closed-circuit test can obtain concentrate that basically satisfied the demand of LJ-55, the grade of concentrate is 54.75%, and the recovery is higher. But in -0.045mm fraction, it is difficult to remove iron and titanium impurity because their fine grit. The grade is Al2O3 48.17% and recovery 14.87%, it can be used in raw material which iron and titanium impurity has less influence. The total recovery of ramified flotation process achieve 84.35%.The research on the mechanism shows that the adsorption of collector on the kyanite surface was much more than that of quartz surface. The collector effect in the kyanite surface with chemical and physical adsorption.