Vanadium leaching method for high-chrome vanadium residues

Abstract

The invention provides a vanadium leaching method for high-chrome vanadium residues. The vanadium leaching method includes the process steps that high-chrome vanadium residues are smashed into particles with the granularity smaller than 150 mesh; the particles are put in the microwave condition and the air atmosphere to be heated and baked to obtain high-chrome vanadium residue clinker, wherein the heating frequency of microwaves is controlled to be 2 GHz to 3 GHz, the heating temperature is controlled to be 700 DEG C to 1000 DEG C, and the heating time is controlled to be 10 min to 120 min; the high-chrome vanadium residue clinker is smashed into particles with the granularity smaller than 200 mesh; a dilute sulphuric acid solution with the concentration of 0.5 mol/L to 6 mol/L is added to the clink particles, the mixture is stirred and leached for 10 min to 180 min at the temperature of 70 DEG C to 100 DEG C; and vanadium-containing filtrate and vanadium tailings are obtained after the mixture is filtered and separated. The method is put forward for high-chrome vanadium residues without effective treatment methods on the current domestic market, various types of high-chrome vanadium residues with the chrome content reaching up to 8% to 14% can be effectively processed, and the final vanadium leaching rate reaches 86% or above.

Description

technical field [0001] The invention relates to a method for extracting vanadium from vanadium slag, in particular to a method for extracting vanadium from high-chromium vanadium slag. Background technique [0002] As an important valuable metal element, vanadium has been widely used in metallurgical industry and chemical industry. At present, the output of vanadium extracted from vanadium-titanium magnetite accounts for about 90% of the total output of vanadium in industrial production. At present, the method of extracting vanadium from vanadium-titanium magnetite in China is mainly pyrometallurgy. This method is to crush the vanadium-titanium magnetite and add a certain amount of additives, and then sinter it into sinter or pellets, and then mix it with coke Put vanadium into the molten iron from sinter or pellets together to form vanadium-containing molten iron, then put the vanadium-containing molten iron into the converter, add some oxidant and coolant into the convert...

AI Technical Summary

Problems solved by technology

But this method mainly has two disadvantages: ① a large amount of Cl is produced during roasting 2 , SO 2 and other toxic and harmful gases, seriously polluting the environment; ②The tailings after vanadium extraction contain a large amount of sodium elements, which exceeds the requirements of blast furnace smelting, and it is difficult to return to the blast furnace for sintering for recycling. At the same time, it caused a serious waste of resources

The problems of this method are as follows: 1. the extraction rate of vanadium is low, generally below 80%, and the recovery rate for high-chromium vanadium slag is lower, often less than 70%; It will greatly increase the consumption of sulfuric acid and increase the production cost

[0005] The third method is the blank roasting-concentrated sulfuric acid acid leaching method. This method uses traditional muffle furnace or rotary kiln to directly heat, roast and oxidize the vanadium slag, and then uses concentrated sulfuric acid acid leaching to obtain a vanadium-containing solution. Vanadium slag is only for vanadium-containing iron water blasting vanadium vanadium slag, not suitable for high chromium vanadium slag

The trivalent vanadium in normal spinel is difficult to dissolve in acid, and can only be extracted after destroying the spinel phase and oxidizing the vanadium in it to tetravalent or pentavalent. The common roasting used in these three methods The method can only be aimed at this kind of vanadium spinel

For high chromium vanadium slag, chromium mainly exists in chromium spinel (FeCr 2 o 4 ), which is in solid solution with vanadium spinel, and chrome spinel is a kind of ore that is more difficult to oxidize and decompose than vanadium spinel, and the extraction method of ordinary vanadium slag is used, and the recovery rate of vanadium is extremely low

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