Method of treatment, stabilization and heave control for chromite ore processing residues (COPR) and chromium contaminated soils

摘要

A process for stabilizing chromium in a chromite ore processing residue (COPR) comprises the steps of adding an acid to consume the excess alkalinity of the COPR, resulting in a pH of less than 10; and adding a chemical reductant to the COPR to convert any hexavalent chromium present to trivalent chromium. A source of sulfate may be added to the COPR to reduce heave potential and improve its geotechnical stability. Treated COPR may be encapsulated in a material suitable to prevent contact between the COPR and water, such as an asphalt.