System and method for producing powdery vanadium by using chlorination process

Abstract

The present invention discloses a system and a method for producing powdery vanadium by using a chlorination process. According to the present invention, through fluidized bed oxidative granulation treatment, the mineral phase reforming and the mineral particle growth of the vanadium residue are achieved; through calcium fixing treatment with carbon dioxide, the decalcification of the vanadium residue is achieved; the vanadium in the vanadium residue is converted into gaseous vanadium oxytrichloride through selective chlorination, and most of impurities such as iron, manganese, phosphorus, titanium, silicon and the like are remained in the chlorinated residue so as to effectively separate vanadium and other impurities; the gaseous vanadium oxytrichloride is sequentially subjected to dust removal, leaching, settlement, rectification purification, catalytic oxidation and other processes to prepare the high-purity vanadium pentoxide powder (powdery vanadium); the chlorinated residue is subjected to gas phase hydrolysis dechlorination treatment, and the dechlorination residue returns to iron making; and with the system and the method, the clean comprehensive utilization of vanadium residue is achieved while the sensible heat of the high temperature flue gas of the chlorination furnace is effectively utilized so as to achieve the purposes of energy saving and consumption reduction.

Description

technical field [0001] The invention belongs to the fields of metallurgy and chemical industry, in particular to a system and method for producing vanadium powder by chlorination. Background technique [0002] Vanadium pentoxide powder (vanadium powder) is an important metallurgical and chemical material, which has been mainly used as an additive to iron-based alloys to produce alloy steel. In recent years, with the rapid development of industrial technology, the application proportion of vanadium pentoxide in aerospace alloys, energy storage materials, petrochemical catalysts and other fields has gradually increased. In particular, the rapid development of energy storage materials (all-vanadium redox flow battery electrolyte, lithium vanadate cathode material) and high-performance aerospace alloys (vanadium-aluminum series, vanadium-titanium alloy) industry has produced high-quality and high-purity vanadium pentoxide. Huge demand. [0003] Vanadium-titanium magnetite is t...

AI Technical Summary

Problems solved by technology

However, the vanadium slag in this process directly enters the chlorination furnace without pretreatment, which will reduce the selectivity of vanadium chlorination, convert a large number of harmful elements into chlorides, and greatly increase the cost of subsequent distillation purification and chlorination residue treatment

The chlorination flue gas volatilized from the chlorination furnace is directly exchanged for heat without dust removal treatment, which will cause pipeline blockage and seriously affect production

The gas phase hydrolysis process will produce a large amount of vanadium-containing hydrochloric acid, which will increase the cost of environmental protection

Moreover, the heat balance of the chlorination furnace, the sensible heat of the high-temperature chlorination flue gas and the chlorination residue are not well utilized.

[0005] In summary, the existing chlorination vanadium extraction process presents significant technical superiority, but there are still many outstanding problems: (1) the chlorination selectivity is poor, and when the vanadium element is chlorinated in the vanadium resource, it will cause The chlorination of other iron, chromium, calcium, phosphorus, titanium, and silicon leads to difficulties in rectification and purification and treatment of chlorination residues; (2) chlorination and roasting of vanadium resources is a strong exothermic process, and the heat generated by the chlorination reaction can be In addition to satisfying the preheating of solid and gas reaction materials, heat exchange and cooling are still required

Distillation and wastewater crystallization require a lot of energy

The energy of the preceding and following processes cannot be effectively coordinated and utilized, which will greatly increase energy consumption and increase production costs; (3) the preparation of industrial vanadium products vanadium pentoxide by vanadium chloride (vanadium oxychloride) lacks an efficient and clean technical route. The hydrochloric acid solution has a high solubility, and the direct liquid phase hydrolysis will cause the recovery rate of vanadium to be too low. Although the use of ammonium salt precipitation can increase the precipitation rate of vanadium, it will produce a large amount of ammonia nitrogen waste water; although the process of gas phase hydrolysis avoids the production of Ammonia nitrogen will separate water, but it will bring a large amount of vanadium-containing hydrochloric acid, and the environmental problems are prominent; (4) the existing chlorination vanadium extraction process is mainly for ordinary vanadium slag, and there is no efficient chlorination method for high-calcium and high-phosphorus vanadium slag extraction technique

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