Process for preparing sugar by two-step method and device thereof

Abstract

The invention discloses a process for preparing sugar by a two-step method and a device thereof. The process comprises the following steps: adding water into crude sugar for dissolving to obtain crude syrup; feeding the crude syrup into a primary filter and a micro-filtration membrane in sequence for filtering to obtain filtrate; feeding the filtrate into a first ion exchange resin tower to obtain a first penetrating fluid, wherein the first ion exchange resin refers to macroporous strong-basicity anion exchange resin; feeding the first penetrating fluid into a second ion exchange resin tower to obtain a second penetrating fluid, wherein the second ion exchange resin refers to strong-acidity cation exchange resin, weak-acidity cation exchange resin or a mixing bed of anion and cation exchange resin; feeding the second penetrating fluid into an evaporator for concentrating to obtain sucrose concentrated liquor; and crystallizing, centrifuging and drying to obtain a sucrose finished product. The process disclosed by the invention can be used for producing high-purity refined sucrose in batch, wherein a pigment removal rate reaches 99.9%, a salt removal rate reaches 98%, and sucrose component of the product reaches 99.9% which reaches the standard of national senior sugar.

Description

[0001] technical field [0002] The invention relates to a process and device for two-step sugar production, belonging to the technical field of sugar production. [0003] Background technique [0004] The sugar production in most developed countries in the world adopts the "two-step" sugar production method. Most sugar factories produce raw sugar, which is then supplied to refineries to produce refined sugar. The "two-step method" sugar production means that the sugar material first uses a relatively simple process (lime method) to produce raw sugar (that is, rough sugar), and then dissolves it, and recrystallizes it after purification to produce white sugar. A kind of white granulated sugar with high index requirements, higher color value, lower color value, and fewer impurities), in decolorization and desalination, it needs to be treated by ion exchange and other aspects. The main advantage of the "two-step method" is that after secondary clarification to remove impur...

AI Technical Summary

Problems solved by technology

[0005] However, the existing production of refined sugar adopts the original process of lime precipitation and sulfur bleaching

This method has the following disadvantages: First, the plate and frame filter press is used, which is a relatively traditional, relatively low degree of automation, and labor-intensive equipment. Removing impurities such as colloids and tannins in the syrup will bring a large production load to the subsequent process sections; secondly, the use of lime precipitation technology will generate a large amount of residues, which will seriously pollute the environment. A new impurity --- ash is introduced into the process, resulting in lower product quality; third, the decolorization of this process is the use of sulfur fumigation, there will be sulfur residues in the product, which is harmful to human health, and the sugar bleached by sulfur dioxide will not be stored for a long time. Chromatography will occur after

With the further improvement of the country's food safety requirements, this method will be restricted in use; fourth, without using ion exchange desalination, the residual salt in the sugar solution cannot be removed, resulting in high ash content of the product, low quality or unqualified, Fourth, the traditional three-effect evaporator is used, which wastes a lot of energy. Compared with advanced technologies such as MVR, the energy consumption is higher

Fifth, the relevant process parameters have not been optimized, resulting in waste of energy

Images