A Comparative Study to Assess the Efficiency of Wet Beneficiation Techniques for Treatment of Low-Grade and High-Grade Bauxite Ore

Abstract

Bauxite is the basic raw material of aluminium used to extract alumina in Bayer’s process. With the huge demand and the rapid development of the global alumina industry, bauxite consumption is rising and has reached more than 160 million tonnes per year. With such a high demand for aluminium, it is becoming more difficult to meet the consumption due to the gradual global decline of high-grade bauxite resources. In the current market scenario, treating bauxites containing more than 5% reactive silica (SiO2) is generally considered uneconomic due to excessive soda consumption in Bayer’s process. The present study is conducted to examine the influence of the wet beneficiation process in the pre-treatment of low-grade and high-grade bauxite ores and a comparative analysis of the results obtained regarding alumina recovery and silica reduction. For this study, High-Grade (HG) and Low-Grade (LG) bauxite ore samples were collected from different bauxite mines of the East Coast region and subjected to wet beneficiation. Comparative chemical analysis of the before and after beneficiation samples revealed the wet beneficiation process to be significantly effective in the pre-treatment of LG bauxite samples with an average increment of 10.84% in the alumina content and 18.38% average reduction in silica after wet beneficiation.