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Of alumina, high silicon, low alumina-silica ratio type of bauxite for the Bayer process production of alumina, for the use of a centrifugal force field for sorting, in order to achieve the requirements of alumina-silica ratio, the more important significance. In this experiment, the Al-Si than 4.39 Henan Zhongzhou low grade bauxite as the object of study, a systematic study of the impact of cyclone separation process factors. Hydrocyclone influencing factors including the structure and operating parameters of the cyclone. The study conducted by the impact of the structure and operating parameters, the results showed that: underflow port diameter change the cyclone air column and the maximum tangential velocity trajectory surface changes in the bottom stream that enters a diaspore and silicic acid The amount of mineral salts increases, reducing the alumina-silica ratio of the bottoms stream, the sorting and grading effect is adversely affected. Cone angle changes, zero speed of the cyclone envelope surface change, the impact of the sorting and grading of the effect of a diaspore and silicate minerals. 11 ° cone angle hydrocyclone underflow port 6mm, sorting results of underflow A / S was 6.87, the bottom stream Al2O3 the recovery rate of 69.88 percent, overflow A / S 2.32, overflow SiO2 in recovery rate of 56.02%. The test was found to mine the pressure to improve the separation efficiency also will increase. Increasing the tangential velocity of the coarse ore pressure can increase in the sorting process, the fine particles into the underflow. Therefore, the separation efficiency of the diaspore and silicate minerals improve the classification efficiency to reduce, but to increase mine pressure. Swirler cone angle of 11 °, and when to mine the pressure of 0.4MPa, the the sorting results obtained for the the bottom current A / s was 7.33, the recovery rate of the bottom stream of Al2O3 70.52%, overflow A / s 2.30 overflow of SiO2 recovery rate of 57.14%. In general, the mineral concentration by the density and viscosity of the slurry affect sorting results. Sorting results with the cone angle of 15 ° to the ore concentration increases lower; sorting results basically 7 ° cone angle is also reduced with increases to the mineral concentration, but when the mineral concentration 8%, curve fluctuations, better test results. Cone angle of 15 ° to the mineral concentration of 10%, the experimental results underflow A / S 6.54, the bottom stream Al2O3 recovery of 75% the overflow A / S 2.27, overflow SiO2 recovery rate 49.01%; When the the cyclone cone angle of 7 ° to the mineral concentration of 8% to achieve a better separation effect, the end of stream A / S 5.58, the bottom stream Al2O3 the recovery rate was 83.01%, overflow A / S of 2.14, the overflow of SiO2 recovery rate of 34.74%. Under normal circumstances, when the more coarse particles into the compound, the separation of the larger particle size, the bottom stream of high concentration, low classification efficiency, the separation effect is not good. When more into the compound by fine-grained isolated small particle size, the differences between the materials is not conducive to separation. To the fineness of separation efficiency affect the test results show that: the end of stream mouth diameter of 6mm to the fineness-0.074mm accounted for 60%, and get better separation effect, the end of stream A / S to 5.32, the bottom flow Al2O3 The recovery rate of 86.48 percent, overflow A / S of 2.32, the flood of SiO2 recovery rate of 26.07%.
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