Titanium dioxide hydrolysis waste acid recycling treatment process

Abstract

The invention provides a titanium dioxide hydrolysis waste acid recycling treatment process. The process comprises the following steps: (1) collecting generated wastewater, freezing for crystallizing,carrying out heat exchange, and then carrying out pretreatment; (2) enabling pretreated produced water to enter a first-section nanofiltration unit; (3) enabling the concentrated solution of the first-section nanofiltration unit to enter a second-section nanofiltration unit, returning the water produced by the second-section nanofiltration unit to the first-section nanofiltration unit for water feeding; (4) enabling water produced by the first-section nanofiltration unit to enter an evaporation unit, performing evaporative concentration, and enabling condensed water of the evaporation unit toenter a reverse osmosis unit; and (5) enabling concentrated water of the second-section nanofiltration unit to enter a resin adsorption unit, enabling effluent of the resin adsorption unit to enter aheat exchange unit, enabling the wastewater subjected to heat exchange to enter a reaction kettle, using the wastewater subjected to reaction as inlet water of the evaporation unit, and then crystallizing and drying to obtain a polyferric product. The process provided by the invention can effectively treat the titanium dioxide hydrolysis waste acid, realizes zero-discharge recycling of the wasteacid, and realizes waste-to-treasure.

Description

technical field [0001] The invention belongs to the field of paint wastewater treatment, and in particular relates to a resource utilization treatment process of titanium dioxide hydrolysis waste acid. Background technique [0002] Titanium dioxide is widely used in the manufacture of coatings, high-grade white paint, white rubber, synthetic fibers, welding electrodes, lightening agents for rayon, fillers for plastics and high-grade paper, etc. It is also used in telecommunications equipment, metallurgy, printing, printing and dyeing, enamel and other industries. [0003] The current common method of titanium dioxide production is the sulfuric acid method. The main raw materials for the production of titanium dioxide by the sulfuric acid method are titanium ore (ilmenite or acid-soluble titanium slag) and sulfuric acid. The production process can usually be divided into ten steps: drying and crushing of titanium ore, acid hydrolysis of titanium ore , Purification of titani...

AI Technical Summary

Problems solved by technology

[0013] To sum up, the current commonly used waste acid treatment methods are mostly neutralization, adding lime, liquid alkali or ammonia water, etc., but waste water or waste acid not only contains a large amount of acid, but also contains a high concentration of iron ions. Treating titanium dioxide production wastewater in a peaceful way will not only consume a large amount of alkali, but will also produce a large amount of iron slag

In addition, after neutralization, the treatment and discharge of wastewater will also be a problem

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