Process of industrialize for waste acid concentrition recovering used in titanium white production by sulfuric acid method

Abstract

An industrial process for reclaiming the waste acid in the production of titanium white powder by sulfuric acid method features that the waste acid is concentrated by fume and then by steam. Its advantages are high efficiency, low cost, and no environmental pollution.

Description

technical field [0001] The invention relates to an industrialized technology for concentrating, recovering and reusing waste acid produced in the production of titanium dioxide by sulfuric acid method, more specifically, it is an industrialized method for concentrating and reusing waste acid in the production of titanium dioxide by sulfuric acid method. Background technique [0002] Titanium dioxide, also known as titanium dioxide, scientific name titanium dioxide (TiO 2 ), white powder, non-toxic and harmless, is an important inorganic chemical raw material, its chemical properties are very stable, it has excellent physical properties, optical properties and pigment properties, and has excellent whiteness, decolorization power, covering Strength, opacity and chalking resistance, it is one of the whitest pigments found in the world. It is widely used in coatings, plastics, papermaking, chemical fiber, ink, rubber, medicine, food and cosmetics industries, and has a wide rang...

AI Technical Summary

Problems solved by technology

[0004] At present, sulfuric acid method or chlorination method is used in the world to produce titanium dioxide. The sulfuric acid method has the advantages of sufficient raw material sources and low production costs. h 2 SO 4 Calculated, the same below), every ton of titanium dioxide produced produces about 4 to 5 tons of waste acid, if the waste acid is not recycled, it will cause a lot of waste of precious resources, and improper disposal will cause serious harm to the environment

The use of neutralization treatment not only consumes a large amount of alkali (lime, carbide slag), but also produces a large amount of industrial sludge (industrial gypsum), and the operating cost is huge, which is unbearable for enterprises

[0005] After searching, it was found that the invention patent application with the publication number CN1608716A discloses a "recovery method for waste sulfuric acid and waste gas produced in the production process of titanium dioxide", which is concentrated by the generated rotary kiln flue gas (gas-liquid), three-stage steam Concentration, three-stage series crystallization kettle concentration, silicon carbide evaporator and other multi-stage (up to 7 stages) concentrated waste acid concentration reaches 80-90%, and also extracts the titanium dioxide entrained in the waste acid. This recovery method exists as follows Disadvantages: (1) Large steam consumption, high power consumption, and high operating costs

(2) Concentration efficiency is low, the concentration of waste acid can only reach 80-90% after 7-stage concentration, the operation is unstable, and the waste acid with a concentration of 80-90% is not the most suitable for reuse in the production process of titanium dioxide. The acid concentration can be reused at 55-65%

(3) There are many operating equipment, complex structure and high investment

(4) The operation of the equipment is complicated and the maintenance is difficult

(5) The process design is complex, and it is not easy to combine with the titanium dioxide production process and promote each other

(6) Equipment and pipelines are prone to fouling and blockage, etc.

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