关键词: 铬铁矿, 石英, 提铬降硅, 摇床重选

Abstract: A chromite ore in Pakistan contains high silicon with Cr₂O₃ content of 50.46% and SiO₂ content of 3.80%. Chromite is the only useful metal minerals in the ore（mainly in the form of chromium spinel，distribution rate of 99.53%），and mainly appeared coarse grain（particle size greater than 0.1 mm accounting for 93.90%）with mainly allotriomorphic granular texture and massive structure. Most of the bro⁃ ken chromite is zonal distribution，and the transparent mineral quartz is filled between the chromite masses. In order to reduce the silicon content in the ore，the beneficiation test was carried out. The results showed that the ore was treated by the process of gravity separation and middle ore regrinding and reseparation， and finally four concentrate products were obtained. The comprehensive concentrate has Cr₂O₃ grade of 54.90%，Cr₂O₃ recovery rate of 88.40%，and SiO2 content of 1.25%.The content of SiO₂ in all concentrate products meet the requirements，and the effect of chromium extraction and silicon reduction is achieved.

Key words: chromite, quartz, chromium extraction and silicon reduction, gravity separation by shaking table