Method for extracting tungsten from tungsten mineral by using soda and adopting high-pressure leaching process

Abstract

The invention discloses a method for extracting tungsten from tungsten mineral by using soda and adopting high-pressure leaching process, comprising the following steps: adding soda and additives into primary tungsten autoclaving slag, carrying out secondary autoclaving at high temperature and pressure; separating the leaching solution from the slag; carrying out primary autoclaving to the tungsten by the leaching solution; separating the primary autoclaving slag from the crude sodium tungstate solution, wherein the primary autoclaving slag is used as the raw material; and mixing the tungstate with the secondary autoclaving leaching solution to prepare slurry. The liquid-solid ratio is controlled to be (3-5):1 in the step of adding the soda and the additives into the primary autoclaving slag and mixing to prepare the slurry, and the soda has the excess coefficient of 2.0-2.5. The liquid-solid ratio is controlled to be (3-5):1 in the step of mixing the tungstate with the secondary autoclaving leaching solution to prepare the slurry. The primary autoclaving temperature and the secondary autoclaving temperature are both 170-240 DEG C, the primary autoclaving pressure and the secondary autoclaving pressure are both 0.9-2.8MPa, and the primary autoclaving time and the secondary autoclaving time are both 2-4 hours. The additives are solid caustic soda and alumina. The method adopts the soda to autoclave the tungsten mineral to extract tungsten at counterflow by using soda at high pressure, so that the leaching rate of the tungsten mineral is more than 99%, the content of WO3 in the tungsten slag is less than 1.0%, the use amount of soda is reduced, and the content of soda in the leaching solution is reduced effectively.

Description

technical field [0001] The invention relates to a method for extracting tungsten in tungsten smelting, in particular to a method for extracting tungsten in tungsten minerals by using a soda high-pressure leaching method. Background technique [0002] At present, the decomposition and leaching methods for various types of tungsten minerals mainly include caustic soda leaching method, combined pressure cooking method, fluoride decomposition method, acid decomposition method, and soda high pressure leaching method. Among them, the caustic soda leaching method is not very ideal for the decomposition rate of scheelite and tungsten ore, and the excess coefficient of caustic soda is large, and the WO in slag 3 Later, Li Honggui invented the patented technology of introducing a mechanical activation process into the above method. Although the decomposition rate has been improved to a certain extent and the excess coefficient of caustic soda has been reduced, the tungsten in tungsten...

AI Technical Summary

Problems solved by technology

Soda high-pressure leaching method can solve these problems, but the temperature and pressure of soda pressure cooking are high, the heat energy waste of intermittent operation is serious, and the excess coefficient of soda is large, generally about 4 times, and it is also a difficult problem to recover the remaining soda in the solution

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