Process for preparing glutamic acid crystallization

Abstract

The invention discloses a preparation method of glutamic acid. The method comprises filtering glutamic acid fermenting liquor via a ceramic membrane for removing thallus to obtain clear glutamic acid fermenting liquor, and performing gradient cooling and crystallizing in a crystallization tank by employing intermittent-continuous isoelectric point method while reducing the pH value of the fermenting liquor in the crystallization tank by adding sulfuric acid and employing shell and tube porous sprinkling method, wherein the feed liquor is continuously discharged to a lower stage tank using overflow on tank, and two thirds of the feed liquor of the lower stage crystallizing tank comes from an upper stage crystallization tank via overflow, and one third of the feed liquor of the lower stage crystallizing tank is added with concentrated solution. The glutamic acid crystal obtained by the preparation method has alpha type crystal.

Description

technical field [0001] The invention relates to a method for producing glutamic acid crystals. Specifically, the invention relates to a method for preparing glutamic acid crystals by isoelectric point crystallization when glutamic acid is produced by fermentation. Background technique [0002] Glutamic acid is mainly used in the production of monosodium glutamate. The most widely used method for the production of glutamic acid at home and abroad is the fermentation method. There are many techniques for extracting glutamic acid from the fermentation broth. The main methods are: isoelectric extraction of glutamic acid Amino acid, ion exchange method to extract glutamic acid, zinc salt method to extract glutamic acid, hydrochloride method to extract glutamic acid or electrodialysis method to extract glutamic acid, etc. [0003] Among them, the extraction of glutamic acid by the isoelectric method utilizes the following properties of glutamic acid: at the pH of the isoelectric p...

AI Technical Summary

Problems solved by technology

The specific extraction methods can be divided into intermittent isoelectric method and continuous isoelectric method. The advantage of intermittent isoelectric method is that the process is mature and the crystal particles are relatively uniform. The disadvantage is that it cannot be operated continuously and the efficiency is low; , each level of crystallization tank is set with a fixed isoelectric pH value, which is easy to control, but the disadvantage is that the particles are not uniform; in the link of reducing the pH value of the crystallization tank and adding sulfuric acid, the traditional process uses directly connecting the sulfuric acid pipeline to the crystallization tank. When sulfuric acid is added, partial supersaturation is prone to occur and β-type crystals are produced. β-type crystals are not easy to be centrifuged and dehydrated, and the bulk density is small, which brings certain difficulties to later packaging and transportation. Type formation

For example, the patent application CN88103158 of Tianjin Light Industry Design Institute, etc., the patent ZL96116404.2 of Wuxi Light Industry University and the patent ZL02109965.0 of Liu Shizhai all adopt continuous isoelectric crystallization to extract glutamic acid, but still fail to overcome the above defects

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