CN110846443A

CN110846443A - Method for optimizing crystallization by back extraction of acesulfame-K syrup

Info

Publication number: CN110846443A
Application number: CN201911123210.9A
Authority: CN
Inventors: 沈孝峰; 石剑; 刘刚
Original assignee: Anhui Jinhe Industrial Co Ltd
Current assignee: Anhui Jinhe Industrial Co Ltd
Priority date: 2019-11-16
Filing date: 2019-11-16
Publication date: 2020-02-28

Abstract

The invention relates to an acesulfame sugar water back extraction crystallization method, which is characterized by comprising the following steps: (1) fully mixing sugar water produced in a neutralization section with dichloromethane according to the volume ratio of 8-10:1, and then separating; (2) the heavy phase enters a rectification system for recovery, the light phase is thermally treated to evaporate dichloromethane, and the dichloromethane enters the rectification system for recovery, wherein the thermal treatment temperature is 60-80 ℃; (3) concentrating the sugar water after heat treatment by MVR, and preparing crude sugar by freezing, crystallizing and centrifuging; (4) mixing the crude sugar, water and active carbon according to the mass ratio of 3:1:0.02, heating to 82-95 ℃, thermally dissolving and decoloring, filtering, freezing, crystallizing, centrifuging and drying to obtain the finished product. The invention has the advantages that: the recrystallization step is reduced, the process is simple and smooth, the investment is low, the production efficiency is high, and the crystallization production stability is high; the steam consumption is reduced, the refrigeration load is reduced, the power consumption is reduced, and the energy is saved; through reasonable proportioning of materials, the impurity content in the finished product can be effectively reduced.

Description

Method for optimizing crystallization by back extraction of acesulfame-K syrup

Technical Field

The invention belongs to the technical field of acesulfame potassium production, and relates to a method for optimizing crystallization by back extraction of acesulfame potassium syrup.

Background

The crystallization process in the prior acesulfame potassium production is shown in figure 2, sugar water is preheated, concentrated by MVR, concentrated liquid is frozen and centrifuged to prepare crude sugar, the crude sugar is added with water for hot dissolution, frozen, crystallized and centrifuged again to prepare recombinant sugar, the recombinant sugar is added with active carbon and water for hot dissolution again, mixed, decolored and filtered, and frozen, crystallized and centrifuged for the third time to prepare finished sugar, and the like; the production is intermittent, the utilization rate of the device is low, the impurity content in the finished product is high, the product quality fluctuates, and the product quality is not high.

Disclosure of Invention

The invention aims to provide a method for back extraction and crystallization of acesulfame sugar water, aiming at overcoming the defects in the prior art.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

the method for back extraction and crystallization of acesulfame-K syrup is characterized by comprising the following steps:

(1) putting sugar water (specific gravity 1.07-1.10) produced in the previous working section (neutralization working section) and dichloromethane (specific gravity 1.33) into a mixer according to the volume ratio of 8-10:1, fully and circularly mixing, and separating by a layering tank;

(2) the separated heavy phase (dichloromethane) enters a rectification system to recover dichloromethane, the separated light phase (sugar water) is subjected to heat treatment to evaporate residual dichloromethane (boiling point 39.8 ℃), and the dichloromethane enters the rectification system to be recovered, wherein the heat treatment temperature is 60-80 ℃;

(3) concentrating the heat-treated sugar water by MVR, freezing the concentrated solution (less than or equal to 15 ℃) to crystallize, and centrifuging to obtain crude sugar;

(4) mixing the crude sugar, water and active carbon according to the mass ratio of 3:1:0.02, heating to 82-95 ℃, performing thermal dissolution and decoloration to obtain saturated solution, filtering the saturated solution, performing freezing (less than or equal to 15 ℃) to crystallize, centrifuging and drying to obtain the finished acesulfame potassium.

The invention has the advantages that:

1. compared with the prior art, the method adopts a back extraction optimization crystallization method, has less recrystallization steps, reduces the operation complexity, greatly improves the production efficiency and saves energy; 2. the crystallization production stability is improved, the steam consumption is reduced, the refrigeration load is reduced, the power consumption is reduced, the steam is saved by 1.5 tons/ton sugar through long-term operation and calculation, and the power load is reduced by 150 degrees electricity/ton sugar; the cost is reduced, 330 yuan/ton of sugar is reduced, and the product competitiveness is enhanced; 3. the method has simple and smooth process and less investment; the crystallization process is shortened (three-step crystallization is changed into two-step crystallization), personnel are reduced (1 person/4 shifts are not needed at present), and the reaction efficiency of the whole production process is optimized; 4, the impurity content in the finished product can be effectively reduced by reasonably proportioning the materials, the organic impurities (by-products of the sulfonation reaction in the previous working section) are reduced to 8-12ppm from about 18ppm in the old process, and the product quality is improved.

Drawings

FIG. 1 is a flow chart of a method for back extraction crystallization of acesulfame potassium sugar water;

FIG. 2 is a flow chart of a crystallization process in the production of acesulfame potassium in the prior art.

Detailed Description

According to the figure 1, the method for the acesulfame sugar water back extraction crystallization comprises the following specific implementation steps:

example 1

(1) Respectively pumping sugar water (specific gravity of 1.07-1.10) and dichloromethane (recovered and rectified dichloromethane or raw material, specific gravity of 1.33) from a neutralization section into a mixer at 10L/h and 1L/h, fully and circularly mixing for 30min, standing for 10min through a layering tank, and separating;

(2) the separated heavy phase (dichloromethane) enters a rectification system to recover dichloromethane, the separated light phase (sugar water) is heated at 70 ℃ for 30min to evaporate dichloromethane (700L-1200L), and the dichloromethane enters the rectification system to be recovered for standby;

(3) concentrating the sugar water after heat treatment in the step (2) by MVR, freezing the concentrated solution (80-90 ℃) by frozen saline (less than or equal to-8 ℃) to below 15 ℃, crystallizing for 30min, and centrifuging for 5min at 1500r/min to obtain crude sugar;

(4) mixing 3000Kg of crude sugar, 1000Kg of water and 20Kg of active carbon, heating to 82-95 ℃ for thermal dissolution and decoloration to obtain saturated solution, filtering the saturated solution to remove the active carbon, freezing (less than or equal to 15 ℃) for crystallization for 30min, centrifuging at 1500r/min for 5min, and drying at 90-130 ℃ for 10min to obtain the finished acesulfame potassium.

Claims

1. The method for back extraction and crystallization of acesulfame-K syrup is characterized by comprising the following steps:

(1) putting sugar water produced in the previous neutralization section and dichloromethane into a mixer according to the volume ratio of 8-10:1, fully and circularly mixing, and separating by a layering tank;

(2) the separated heavy phase enters a rectification system to recover dichloromethane, the separated light phase is subjected to heat treatment to evaporate residual dichloromethane, and the dichloromethane enters the rectification system to be recovered, wherein the heat treatment temperature is 60-80 ℃;

(3) concentrating the thermally treated sugar water by MVR, and performing freeze crystallization and centrifugation on the concentrated solution to obtain crude sugar;

(4) mixing the crude sugar, water and active carbon according to the mass ratio of 3:1:0.02, heating to 82-95 ℃, performing thermal dissolution and decoloration to obtain saturated solution, filtering the saturated solution, performing freeze crystallization, centrifuging and drying to obtain the finished acesulfame potassium.