A continuous evaporation crystallization system

Abstract

The invention relates to a continuous evaporative crystallization system comprising a raw material inlet, a water replenishing inlet, a preheater, a climbing film evaporator, a gas-liquid separator, a compressor, a pipeline heater, a crystal separator and a PLC (programmable logic controller) automatic control system, wherein an inlet, a first outlet, a second outlet and a third outlet are formed in the gas-liquid separator; the preheater is connected with the climbing film evaporator by virtue of a pipeline, and the climbing film evaporator is connected with the inlet of the gas-liquid separator; the compressor is connected between the gas-liquid separator and the climbing film evaporator by virtue of a stem conveying pipeline; a circulating evaporator is connected between the second outlet and the inlet by virtue of a pipeline; the cooling water after heat exchange of the climbing film evaporator and the cooling water after heat exchange of the circulating evaporator are used as hot sources of the preheater; a cooling water output end of the preheater and the water replenishing inlet are used for replenishing water for the system; the crystal separator is connected with the third outlet of the gas-liquid separator; and the PLC automatic control system is arranged in the continuous evaporative crystallization system to ensure that the continuous evaporative crystallization system has optimized and stable parameters, can save energy and raw materials, and is good in crystallization effect.

Description

technical field [0001] The invention belongs to an evaporation crystallization system, in particular to a continuous evaporation crystallization system with energy-saving and water-saving effects. Background technique [0002] At present, the Mechanical Vapor Recompression technology is a highly efficient, energy-saving and environmentally friendly technology, referred to as MVR. Although many continuous evaporation crystallization systems using mechanical vapor recompression technology are disclosed in the prior art, due to unreasonable process design, many mechanical vapor recompression continuous evaporation crystallization systems generally only have a single-stage steam compressor to supply heat to the evaporator , In the crystallizer part, the material is still not supplied with a large amount of heat, which leads to poor crystallization effect of the existing mechanical vapor recompression continuous evaporation crystallization system, such as fine crystal particle si...

AI Technical Summary

Problems solved by technology

Although many continuous evaporation crystallization systems using mechanical vapor recompression technology are disclosed in the prior art, due to unreasonable process design, many mechanical vapor recompression continuous evaporation crystallization systems generally only have a single-stage steam compressor to supply heat to the evaporator , in the crystallizer part, the material is still not supplied with a large amount of heat, which leads to the poor crystallization effect of the existing mechanical vapor recompression continuous evaporation crystallization system, such as fine crystal particle size and other problems

Of course, some manufacturers will add steam pipes to supplement the heating of the crystallization part, but this greatly increases the complexity of the MVR continuous evaporation crystallization system, and relies on steam boilers, making the MVR system lose its original significant advantage - getting rid of the need for steam boilers dependence on

[0003] In view of these problems, the publication number is CN103203116A Chinese Invention Patent Application Publication Specification discloses a mechanical vapor recompression continuous evaporation crystallization system and method to solve the above problems, the mechanical vapor recompression continuous evaporation crystallization system uses two mechanical vapor compression machine, and the two compressors supply heat to the evaporator and the crystallizer respectively, and also recover the sensible heat of the cooling water for preheating, but the continuous evaporation and crystallization system uses two mechanical steam compressors, purchased The equipment cost of two mechanical steam compressors is very high, and there is no reasonable structure to preheat the material to the bubble point temperature, so the energy consumption of starting the two compressors is also high, and the structure is complicated, resulting in unsatisfactory energy saving effect , the ratio of input cost and saved income is still unreasonable, which also makes it difficult to promote the MVR continuous evaporation crystallization system in my country

[0004] Secondly, the process of the existing MVR continuous evaporation crystallization system is not only immature, but also due to the complexity of the MVR continuous evaporation crystallization system, it is often subject to various disturbances and lacks adaptive feedback control. Once the parameters are unstable, it will easily lead to Poor crystallization or low crystallization efficiency is also a factor that increases actual energy consumption

[0005] In addition to energy saving, the existing MVR continuous evaporative crystallization system rarely considers the recycling of waterways, resulting in the continuous production process of the existing MVR continuous evaporative crystallization system. Heat energy, prevent cooling water pollution, and need a lot of new steam to fill in, wasting water resources

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