Use of Pinched Sluice in Albite Concentration

Abstract

Albite (NaAlSi 3 O 8 ) is an important industrial mineral especially for ceramic and glass production. Major Fe-containing impurity of albite ore is flaky mica minerals. This study was conducted to determine the applicability of pinched sluicing for pre-concentration of albite ore by exploiting shape effect. Effects of feed solid rate, tilting angle of pinched sluice, and splitter position on the rejection of Fe-containing flaky mica were tested. Pulp solid rate was determined to be the most important variable on the rate of mica rejection. Increasing the tilting angle adversely affected the separation efficiency especially above 17°. Distribution of gangue mica in the vertical cross-section of flowing film was tested manipulating the splitter height. Mica particles were observed to be crowded in upper layers of film thickness. So, flaky mica impurity was thought to be separated from feldspar ore, and a pre-concentrate was obtained. All Fe-containing coloring impurities could not be removed due to different mineralogical origins of them in the ore. Optimum operating variables were determined as follows: 56% feed solid rate, 17° tilting angle of pinched sluice, and splitter height lower or closer to 2/3 of the total pulp film thickness. Pulp solid rate of underflow stream almost linearly changed with respect to splitter height.