CHARACTERISATION OF ALUMINA AND SODA LOSSES ASSOCIATED WITH THE PROCESSING OF GOETHITIC RICH JAMAICAN BAUXITE

摘要

Iron oxides occur in Jamaican bauxites predominantly in the mineral forms of goethite and hematite. The relative concentrations of these iron minerals, and their morphologies, in conjunction with the soluble phosphate and available alumina content, have a great impact on alumina refinery operations and associated operational costs. Of the iron minerals, goethite in the Bayer process is generally experienced as being adverse, facilitating alumina losses, sequestration of soda, and rendering the mud more difficult to settle. A fundamental knowledge of the components within Jamaican bauxite that contribute to alumina and soda losses is paramount to finding mitigating solutions. This study focuses on the various components of Jamaican bauxite residue material and examines their propensity to promote gibbsite reversion and their soda adsorption capacity.