Device for directly producing urea solution for vehicles and production method thereof

Abstract

The invention belongs to a device for directly producing urea solution for vehicles and a production method thereof; it comprises a low-temperature methanol washing section, a liquid ammonia washing section and a secondary reverse osmosis device connected with a shift gas pipeline, and a carbon dioxide desorption gas outlet of the low-temperature methanol washing section The feed gas purification adsorption tower is connected to the gas phase inlet of the urea synthesis section, the gas phase outlet of the low temperature methanol washing section is connected to the liquid phase inlet of the urea synthesis section through the liquid ammonia washing section and the synthetic ammonia section, and the solid phase outlet of the urea synthesis section is connected to the liquid phase inlet of the urea synthesis section. The solid-phase inlet of the bubbling agitator is connected to the liquid-phase inlet of the bubbling agitator. The outlet is connected with the vehicle urea storage device; it has the advantages of simple structure, reasonable process method, low cost, stable quality, can effectively replace the existing crystallization process, realize large-scale industrial production and all indicators meet the vehicle urea standard.

Description

technical field [0001] The invention belongs to the technical field of urea production for vehicles, and specifically relates to a direct production that can effectively solve the problem of excessive formaldehyde content in raw materials of urea granules for vehicles, has low cost, stable quality, can effectively replace the existing crystallization process, and realize large-scale industrial production A urea solution device for vehicles and a production method thereof. Background technique [0002] Vehicle urea, scientifically known as diesel engine exhaust treatment fluid, is commonly known as automotive urea, automotive urea, automotive environmental urea, and automotive denitration agent in China. The most commonly used vehicle urea is automotive urea. Urea for vehicles is a colorless, transparent, and clear liquid with a concentration of 31.8%-33.2%. According to the Euro IV standard, 32.5% is currently the standard concentration of urea for vehicles. Urea for vehicl...

AI Technical Summary

Problems solved by technology

[0003] However, the purity requirements of urea for vehicles are very high. In order to produce high-purity urea for vehicles, many companies have tried various methods and approaches. For example, the name of the Chinese invention patent is: a preparation method of urea for vehicles, and the patent number is It is: 201210003845.7, which discloses a method of urea recrystallization to produce high-purity urea, and then mixes high-purity water to produce urea for vehicles, but the production consumes a lot of energy, the cost is high, and a large amount of mother liquor is wasted

The name of the Chinese invention patent is: a production process of tail gas catalytic reducing agent, the patent number is: 201010152076.8, which discloses a continuous filtration and ion exchange technology for adsorption and exchange of metal and non-metal ions; but the process is complicated, higher cost

In addition, the main problem affecting the quality of urea for vehicles produced by enterprises is the widespread occurrence of formaldehyde exceeding the standard, which prevents many enterprises from producing urea for vehicles

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