Application of reflux classifier with closely spaced inclined channels in pre-concentrate process of fine antimony oxide particles

Abstract

In this work, the reflux classifier with closely spaced inclined channels is used as the pre-concentration facility to improve the separation efficiency before the shaking table separation. Three operating parameters of reflux classifier (RC) to pre-concentrate fine(0.023–0.15 mm) tailings of antimony oxide were optimized by response surface methodology (RSM) using a three-level Box-Behnken design (BBD). The parameters studied for the optimization were feeding speed, underflow, and ascending water speed. Second-order response functions were produced for the Sb grade and recovery rate of the concentrate. Taking advantage of the quadratic programming, when the factors of feeding, underflow and ascending water are respectively 225, 30 and 133 cm³/min, a better result can be achieved for the concentrate grade of 2.31% and recovery rate of 83.17%. At the same time, 70.48% of the tailings with the grade of 0.20% were discarded out of the feeding. The results indicated that the reflux classifier has a good performance in dealing with fine tailings of antimony oxide. Moreover, second-order polynomial equations, ANOVA, and three-dimensional surface plots were developed to evaluate the effects of each parameter on Sb grade and recovery rate of the concentrate.

Keywords

reflux classifier / antimony oxide / pre-concentration / inclined channels

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