Continuous anti-solvent-out crystallization membrane crystallization method of erythritol

Abstract

The invention relates to a continuous anti-solvent-out crystallization membrane crystallization method of erythritol. By the characteristic that water has higher permeation rate than a solvent-out agent in a hollow tubular pervaporation permeable membrane, concentration ratio of a solvent-out agent to water in erythritol crystallization mother liquor is gradually increased such that the crystallization mother liquor is oversaturated to solvent out crystals. Thus, the process is also called an anti-solvent-out crystallization process. The use amount of the required solvent-out agent can be less than the use amount in a conventional solvent-out process, and local high oversaturation and overnucleation existing when a solvent-out agent is directly added into crystallization mother liquor can be effectively avoided. In comparison with traditional evaporation and concentration and cooling crystallization process, the invention also can relieve defects such as large magma suspension density and the like. In addition, full continuous production of the erythritol anti-solvent-out crystallization process is also realized, and the solvent-out agent can be recycled. The method of the invention has the following advantages: production cost is reduced; emission of ''three wastes (waste gas, waste water and industrial residue)'' is reduced; and energy is saved.

Description

technical field [0001] The invention belongs to the technical field of production of polysaccharide alcohols, and in particular relates to a method for crystallizing erythritol through continuous reverse elution membranes. Background technique [0002] Erythritol is a natural sugar and functional sweetener. It is widely used in the development of low-calorie health food, functional food or beverage for people with diabetes and glucose discomfort, and children's special tooth cleaning products. The market prospect is very promising. [0003] The industrial production of erythritol mainly adopts the fermentation method. After the fermentation liquid is purified, it is first evaporated and concentrated, and then cooled and crystallized to obtain erythritol crystals. Due to the low concentration of erythritol in the fermented liquid, the operating temperature is higher during normal pressure evaporation and concentration, the evaporation of water is larger, and the energy consum...

AI Technical Summary

Problems solved by technology

Although the above-mentioned disclosed erythritol dissolution and crystallization method (CN 102992957A) is much lower than the traditional erythritol evaporation crystallization energy consumption, strictly speaking, the method is a batch operation, and when the dissolution agent is directly added to the When in the crystallization mother liquor, the local supersaturation at the adding point of the dissolving agent is very large, and the secondary nucleation phenomenon is serious

In addition, in the erythritol dissolution and crystallization method (CN 102992957A) disclosed above, the dissolution agent does not realize the recovery cycle, and the dissolution agent consumes a lot

Images