METHOD OF INTEGRATED PROCESSING OF POLYMETALLIC PRODUCTION WASTES AND RENDERING THEM HARMLESS Russian patent published in 2002 - IPC

FIELD: metallurgy and chemical technology of inorganic substances. SUBSTANCE: method includes chlorination in melt of alkali metal chlorides with obtaining of spent melts and vapor-gas mixture, separation, purification and utilization of titanium tetrachloride, alkali decomposition of vanadium oxytrichloride, precipitation of ammonium metavanadate, separation of its mother liquor, washing and calcination to produce vanadium pentoxide, hydraulic washing of spent melts in reusable solutions, neutralization of pulp with magnesium suspension, separation of sediments of metal hydroxides from solution. In this case, polymetallic vanadium-containing wastes prior to chlorination are preliminarily subjected to reducing melting at 1600-2000 C together with titanium-containing concentrates. Spent chlorate melts are discharged into mortar liquors, and washing waters of ammonium metavanadate are neutralized. After neutralization successively introduced, first, are hyprochloride pulp, then solution of high-molecular flocculant. Hydroxide pulp is held for some time, and clarified part is discharged, thickened part is filtered out, hydroxide sediment is washed, filtrate and washing waters are combined and directed for production of synthetic carnallite. Hydroxide sediment is mixed, first, with insoluble residue formed in hydraulic washing of spent melts and dust trapped in ore melting of titanium-containing concentrates and polymetallic wastes, then, with ground materials containing chlorides and oxides of magnesium, and obtained paste composition is heated and formed into blocks. Titanium-containing concentrates are used in the form of ilmenite and/or rutile, and/or ilmenorutile. Method is used at metallurgical and chemical-metallurgical plants, for example, at titanium-magnesium plants for recovery of vanadium. EFFECT: increased productivity and provision of rendering harmless of sewage waters. 5 cl, 1 ex