Review on treatment and utilization of bauxite residues in China

摘要

Bauxite residue (red mud) is a solid waste produced in the process of alumina extraction from bauxite. More than 70 million tons of bauxite residue is generated annually. Presently, it is stored on land or in the ocean near alumina refineries. However, its high alkalinity is a potential pollution to water, land and air of close proximity. Meanwhile high costs are associated with the large area of land needed for storage of the residue. China is amongst the major producers of alumina in the world. There are some differences between the residues from China and other countries due to differences in ore type and production processes. Significant achievements in treatment and utilization of bauxite residues have been obtained in China in the last decade. In this paper, the properties of bauxite residues generated in China are analyzed and significant aspects to treat and utilize residues from the sintering process and the Bayer process are introduced (e.g., storage, preparation of building materials, application in environmental materials, and recovery of valuable elements). Problems associated with the commercial application of these research achievements are considered.