Method and system for producing ammonium paratungstate through alkaline extraction

Abstract

The invention relates to a method and system for producing ammonium paratungstate through alkaline extraction, and the method comprises the following steps: (1) leaching a tungsten mineral raw material to obtain mixed slurry; (2) carrying out solid-liquid separation on the mixed slurry to obtain a sodium tungstate solution; (3) performing advanced oxidation on the sodium tungstate solution to obtain a primarily purified sodium tungstate solution; (4) performing extraction and back extraction to obtain an ammonium tungstate solution; (5) removing molybdenum to obtain a purified ammonium tungstate solution; (6) crystallizing to obtain an ammonium paratungstate product; the system comprises a leaching device, a filtering device, an advanced oxidation device, an extraction and back extractiondevice, a molybdenum removal device and a crystallization device which are connected in sequence. The method provided by the invention can be used for producing high-quality ammonium paratungstate products, reducing the loss of metal raw materials and avoiding the waste of a leaching agent, and has the advantages of low energy consumption, low labor intensity, good operation environment, no pollution gas release and the like.

Description

technical field [0001] The invention relates to the field of metallurgy technology, in particular to a method and system for producing ammonium paratungstate by alkaline extraction. Background technique [0002] Tungsten resources such as scheelite, black and white tungsten mixed ore, tungsten slime, artificial scheelite, low-grade tungsten-molybdenum mixed ore, and tungsten-containing catalyst waste have become the main raw materials for the tungsten industry. However, most of these raw materials contain surfactants, and the existence of surfactants will have various adverse effects on subsequent processes. For example, the tungsten mineral raw materials containing surfactants are leached to prepare sodium tungstate solution During the process, the surfactant will enter the sodium tungstate solution, and the tungsten mineral raw material containing the surfactant will enter the sodium tungstate solution during leaching to prepare the sodium tungstate solution. In the proce...

AI Technical Summary

Problems solved by technology

The disadvantage of the existing technology is that the high temperature of the roasting process leads to high energy consumption, high labor intensity and poor working environment, and produces a large amount of roasting smoke that is difficult to control, thereby causing huge environmental risks. Due to the small output and high price of most tungsten mineral raw materials, tungsten Mineral raw materials are usually in batches of ten tons, and the tungsten content varies greatly from batch to batch

The random mixing of multiple batches of tungsten mineral raw materials during the roasting process will cause unclear grades of metal raw materials during leaching, which will seriously affect the subsequent batching, leaching and other operations.

In order to ensure the leaching rate of tungsten mineral raw materials, an excessive amount of leaching agent is usually added in production, thus causing waste of leaching agent

In addition, the roasting process also causes a large amount of tungsten mineral raw material loss. For example, the tungsten loss rate caused by the tungsten mineral raw material roasting process in the prior art is about 2.5%, and it will cause a great waste of resources and poor economic efficiency.

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