APPARATUS AND METHOD FOR EXTRACTING METALS AND/OR METAL OXIDES FROM INDUSTRIAL WASTES, PARTICULARLY REFINERY WASTES Russian patent published in 2019 - IPC C22B7/00 B09B3/00 C22B9/10 

FIELD: heating, roasting, melting and retort furnaces.

SUBSTANCE: invention relates to extraction of metals from oil refining wastes. Extraction plant comprises a conveyor furnace, a supply pipeline, an outlet line, a leaching unit and one or more metal separation units. Supply pipeline is connected to the main inlet hole of the furnace for supply of the furnace with solid wastes containing metals, in particular, in oxide form. Output line is connected to the outlet hole of the solid phase furnace for extraction of the solid phase enriched with metal from the furnace. Conveyor furnace comprises an inner chamber extending along a substantially horizontal longitudinal axis and a closed belt conveyor in the chamber, having a substantially horizontal configuration along said axis, and also has an upper surface receiving the treated wastes and transmitting said wastes along said axis in the chamber between two longitudinally opposite ends of the conveyor furnace, having respectively a main inlet and an outlet for the solid phase. Leaching unit is installed after the conveyor furnace and is connected to the outlet hole for the solid phase of the conveyor furnace for the leaching of the solid phase leaving the conveyor furnace, and producing an aqueous solution containing metals extracted from said solid phase. Metal separation units are located after the leaching unit for at least partial separation of metals contained in the solution leaving the leaching unit.

EFFECT: simplified and cheaper leaching process.

26 cl, 6 dwg