Anti-scaling method for treatment process of sewage containing high-concentration molybdenum and zirconium elements

Abstract

The invention discloses an anti-scaling method for the treatment process of sewage containing high-concentration molybdenum and zirconium elements. According to the technical scheme, crystals are added into sewage. The crystals are crystals in different forms such as zirconium molybdate, molybdenum oxide or zirconium oxide, etc. through the research on formation, precipitation and adhesion mechanisms of zirconium molybdate in a nitric acid solution and by the specificity of zirconium molybdate crystal growth process, zirconium molybdate crystals are added into the solution, and large-grained crystals are used for absorbing generated zirconium molybdate particles to prevent adsorption on the inner wall of a container and effectively prevent scale formation. The method is simple to operate,low-cost and safe and environmentally-friendly; and additives contain no substances except solution elements, thus having no unfavorable effect on metal separation and extraction links.

Description

technical field [0001] The invention relates to an anti-scaling method in the sewage treatment process containing high-concentration molybdenum and zirconium elements. Background technique [0002] In the process of industrial metal waste treatment, metal coatings and alloys contain a relatively high proportion of precious metals. Recycling these high-value metal elements can generate considerable economic benefits. In order to extract the precious metal elements in scrap metal as much as possible, nitric acid is usually used to dissolve the metal as a whole and then carry out displacement extraction. However, when the nonmetal contains a certain amount of molybdenum and zirconium elements, when the ionized molybdenum and zirconium are combined in the nitric acid solution, as the temperature changes, zirconium molybdate solids with strong adhesion will be formed in the solution to adhere to The inner wall of the container will form a scale layer after long-term accumulation...

AI Technical Summary

Problems solved by technology

[0010] Disadvantages: 1. The equipment needs to be stopped, which hinders the continuous normal operation of the equipment and increases the operating cost; 2. Since the scale layer is closely combined with the inner wall of the container, this method cannot completely remove the scale layer; 3. Secondly, the staff enters the equipment Cleaning in the environment, the equipment is in the acidic and mixed solution environment for a long time, there are hidden dangers to the safety and health of the staff

4. During the cleaning process, the water consumption is large and resources are wasted

[0013] Disadvantages: 1. High-concentration strong acid and strong alkali environment seriously corrodes the equipment and shortens the service life of the equipment

2. The cost of waste liquid treatment is high and the environmental load is large

[0016] Disadvantages: 1. High energy consumption for high temperature cleaning

2. The reaction rate of weak acid is low, and it takes a long time to completely remove the scale layer

[0019] Disadvantages: The composition of the antiscalant is complicated, which makes it difficult to separate the impurities mixed in the solution, which increases the difficulty of the subsequent precious metal recovery process

[0020] Waste of resources, high operating cost, and large environmental load are the disadvantages of the existing methods. Therefore, a new method that is safe, easy to operate, environmentally friendly and energy-saving is needed to prevent the precipitation of zirconium molybdate solids in the reaction vessel.

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