A kind of phosphorous acid crystallization method

Abstract

The invention discloses a phosphorous acid crystallization method, particularly an energy-storage crystallization method of phosphorous acid in the production process. The method is characterized by sequentially comprising the following steps: preparing a phosphorous acid liquid; concentrating the phosphorous acid liquid; adding ordinary water into the concentrated phosphorous acid liquid, and regulating the 100-DEG C density to 1.155; putting the phosphorous acid liquid with the 100-DEG C density of 1.155 into a jacket-bearing enamel reaction kettle, and introducing cooling water into the jacket while stirring so as to enter the phosphorous acid liquid crystallization process; and putting 1 / 4 of the material in the reaction kettle into a centrifugal drier to perform drying, and meanwhile, quickly adding the phosphorous acid liquid with the 100-DEG C density of 1.155 into the rest 3 / 4 material in the reaction kettle, thereby completing the cyclic-cooling crystallization process. The method can shorten the phosphorous acid crystallization time and greatly enhance the production efficiency.

Description

technical field [0001] The invention relates to a crystal forming method. Specifically, it is an energy storage crystallization method of phosphorous acid in the production process. Background technique [0002] It is known in the chemical industry that phosphorous acid is a solid, and it must be cooled and crystallized to obtain qualified crystals before it can be used. The traditional phosphorous acid crystallization method is to put the hot phosphorous acid liquid that has been deacidified and adjusted to a specific gravity into an enamel mold with a jacket, and while stirring, fill the jacket with cooling water for cooling and crystallization. When the liquid temperature in the enamel reaction tank drops to about 60 degrees, crystallization begins to precipitate. Due to the large amount of heat generated when the phosphorous acid crystals are precipitated, the temperature rises rapidly to about 70 degrees, and the temperature difference with the wall of the enamel is a...

AI Technical Summary

Problems solved by technology

Due to the large amount of heat generated when the phosphorous acid crystals are precipitated, the temperature rises rapidly to about 70 degrees, and the temperature difference with the wall of the enamel is about 30 degrees, which leads to a large amount of crystallization on the wall of the kettle, thus forming a thickness of 2 ~ 2 on the inner wall of the enamel reaction kettle. The crystalline layer with different thickness between 10 cm makes the temperature conductivity of the reactor very poor, thus greatly prolonging the crystallization time

Moreover, after the crystallization is completed, the centrifugal dehydration process is carried out. After the materials in the reactor are exhausted, the above process is repeated, which makes the production efficiency low.