Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for preparing anhydrous citric acid crystal

A technology of citric acid and crystals, which is applied in the field of preparing anhydrous citric acid crystals, can solve the problems of low impurity content, low product quality of anhydrous citric acid crystals, low moisture content, etc., achieve low impurity content, improve the first pass rate, Uniform particle size effect

Active Publication Date: 2014-12-03
COFCO BIOTECHNOLOGY CO LTD
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome the defects of low quality anhydrous citric acid crystals obtained by existing methods, and to provide a crystal that can efficiently obtain uniform particle size, low impurity content, high bulk density and low moisture content that is not easy to agglomerate The method for the preparation of product anhydrous citric acid crystals

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0011] The method for preparing anhydrous citric acid crystals provided by the present invention comprises carrying out concentrated crystallization of citric acid feed liquid, wherein, when the crystal content in the feed liquid reaches 20-40% by weight (preferably 25-35% by weight), the concentrated The crystal slurry liquid obtained by crystallization is classified, and the classification conditions are controlled so that crystals with a particle size of less than 600 μm are separated from the crystal slurry liquid, and part or all of the crystal slurry liquid obtained by classification containing crystals with a particle size of less than 600 μm is returned to the citric acid feed Liquids are mixed together for concentrated crystallization.

[0012] According to the present invention, the conditions of the concentrated crystallization can be the conditions routinely used in the art. Preferably, the conditions of the concentrated crystallization make the particle size of the...

Embodiment 1

[0022] The continuous injection of the citric acid feed solution with a citric acid content of 60% by weight into an effective volume of 20m 3 In the crystallizer, carry out concentrated crystallization at 60 ℃, when the crystal content in the feed liquid reaches 35% by weight, control the feed rate of the citric acid feed liquid and the discharge speed of the crystal slurry liquid that the concentrated crystallization obtains to make the feed liquid The crystal content of the crystal is kept constant, and the crystal slurry obtained by concentrated crystallization (the particle size of the crystal contained is not more than 850 μm) is passed into the hydrocyclone for classification, and the feeding pressure is controlled to be 0.4MPa, and the feeding speed is 3m 3 / h, so that the crystals with a particle size of less than 600 μm are separated from the crystal slurry, and the obtained crystal slurry containing crystals with a particle size of less than 600 μm is returned to the...

Embodiment 2

[0025] The continuous injection of the citric acid feed solution with a citric acid content of 55% by weight into an effective volume of 20m 3 In the crystallizer, carry out concentrated crystallization at 60 ℃, when the crystal content in the feed liquid reaches 30% by weight, control the feed rate of the citric acid feed liquid and the discharge speed of the crystal slurry liquid that the concentrated crystallization obtains to make the feed liquid The crystal content of the crystal is kept constant, and the crystal slurry obtained by concentrated crystallization (the particle size of the crystal contained is not more than 850 μm) is passed into the hydrocyclone for classification, and the feeding pressure is controlled to be 0.2MPa, and the feeding speed is 10m 3 / h, so that the crystals with a particle size of less than 600 μm are separated from the crystal slurry, and the obtained crystal slurry containing crystals with a particle size of less than 600 μm is returned to th...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
particle diameteraaaaaaaaaa
particle diameteraaaaaaaaaa
densityaaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for preparing an anhydrous citric acid crystal. The comprises the following steps: concentrating and crystalizing citric acid liquor, grading the concentrated and crystallized crystal slurry when the content of crystals in the liquor is up to 20-40wt%, controlling the grading conditions so as to separate crystals, with the particle size of less than 600mu m, from the crystal slurry, and returning partially or entirely graded crystal slurry, containing crystals with the particle size of less than 600mu m, and mixing crystal slurry together with citric acid liquor for concentration and crystallization. Through the technical scheme, the anhydrous citric acid crystal which is uniform in particle size, low in the content of impurities, high in piling density, low in moisture content and difficult to cake can be obtained. Furthermore, the method can improve the first-pass yield of citric acid products, the obtained crystal product is not required for a sieving step, therefore, the production efficiency of the anhydrous citric acid crystals can be improved.

Description

technical field [0001] The invention relates to a method for preparing anhydrous citric acid crystals. Background technique [0002] At present, the continuous production method of anhydrous citric acid crystal products in industry includes: firstly, the citric acid fermented liquid is separated from solid and liquid to obtain citric acid clear liquid; , the acid hydrolysis product is decolorized, the decolorized solution is heated and concentrated, and the obtained concentrated citric acid feed liquid is continuously injected into the crystallizer, when the crystal content accounts for 46-60% by weight of the total weight of the mixture of citric acid solution and solid , start to continuously and quantitatively discharge the crystal slurry containing anhydrous citric acid crystals, keep the system running continuously, then directly centrifuge the crystallized crystal slurry, and dry to obtain anhydrous citric acid crystal products. [0003] The disadvantage of the above-...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C07C59/265C07C51/43
CPCC07C51/43C07C59/265
Inventor 罗虎熊结青许贵珍高志林陶俊
Owner COFCO BIOTECHNOLOGY CO LTD