Continuous evaporative crystallizer and evaporation system for light-weight solids

Abstract

The invention relates to a continuous evaporative crystallizer and an evaporation system for light-weight solids. The continuous evaporative crystallizer includes a tank body; a material inlet is disposed on the middle of the tank body; a vapor outlet is arranged on the upper end of the tank body; a liquid outlet is disposed on the lower end of the tank body; a mist eliminator is located in the tank body; an inclined separation board and a horn-shaped expanding mouth are disposed in the middle part of the tank body; the upper end of the inclined separation board is sealed and the lower end is opened, wherein the horn-shaped expanding mouth is located below the inclined separation board with a larger mouth upward and a smaller mouth downward; a crystal slurry extraction pipe is disposed at one end inside the tank body and is connected to the smaller mouth of the horn-shaped expanding mouth. Compared with the prior art, the continuous evaporative crystallizer can extract crystal slurry from above a solution. The continuous evaporative crystallizer is suitable for continuous stable industrial evaporative crystallization of light-weight solids, such as calcium propionate, of which the density is less than a liquid, and can ensure that the two processes, solution heating and water evaporation, are separated at spatial positions.

Description

technical field [0001] The invention relates to an evaporative crystallization device, in particular to a continuous evaporative crystallizer and an evaporator system for light solids whose density is lower than that of liquid. Background technique [0002] The crystallization process is an important operation unit in the chemical process and an important link in the production of chemical products. It is also widely used in other industrial sectors. The density of the solid product is usually greater than the solution density, so the continuous crystallization device commonly used in industry at present such as Oslo crystallizer, DTB crystallizer all is to extract the crystal slurry from the bottom of the crystallization vessel, and then obtains the solid product through filtration and / or drying process ( Ye Tielin, "Chemical Crystallization Process Principles and Applications", Chemical Industry Press, 2006). [0003] Calcium propionate is an important food additive, wide...

AI Technical Summary

Problems solved by technology

Propionic acid reacts with calcium carbonate or calcium hydroxide in the water phase to obtain an aqueous solution of calcium propionate. Since the density of calcium propionate is smaller than that of the solution, it is generally evaporated by intermittent partition heating after the reaction produces calcium propionate. Most of the water is concentrated crystal slurry (US P4700000, 1987; Jia Zhenyu et al. Guangdong Chemical Industry, 1999, No. 2, page 93), which cannot realize large-scale continuous stable production

Chen Guangyu and others passed the calcium propionate solution into the falling film evaporation device to concentrate (Packaging and Machinery, Issue 3, 2015, page 97), which can realize the continuous process, but the solution heating and water evaporation are carried out at the same time, which will cause the solid calcium propionate to be heated. a large amount of deposition on the surface

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