JPH1170000A - Apparatus for purifying sucrose syrup and regeneration of sucrose syrup purification apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sucrose syrup purification apparatus capable of carrying out stable desalting purification treatment. SOLUTION: This apparatus for the purification of sucrose syrup comprises a softening column 1 filled with a cation exchange resin 2 for passing a sucrose syrup, an anion column 3 filled with a strongly basic anion exchange resin 4 for passing a treated liquid passed through the softening column 1, and a mixed bed column 5 filled with a strongly basic anion exchange resin and a weakly acidic cation exchange resin for passing the treated liquid passed through the anion column 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a sucrose solution refining apparatus and a method for regenerating the apparatus. More specifically, the present invention relates to a sucrose liquid refining apparatus in which a softening tower, an anion tower, and a mixed bed tower are combined, and a method for regenerating the same.

[0002]

2. Description of the Related Art Conventionally, a sucrose solution has been purified by subjecting it to a decolorizing treatment by an activated carbon treatment, a bone char treatment and an ion exchange resin treatment, and then to a desalting treatment using an ion exchange resin. As a desalination purification system, a desalination purification system using an anion column using a strong basic anion exchange resin in OH form and a mixed bed tower of a strong basic anion exchange resin in OH form and a weakly acidic cation exchange resin in H form (JP-A-2-2-2954
No. 99) has been proposed. This system is a desalination and purification system that is superior in both throughput and decolorization rate as compared with the conventional desalination and purification systems such as the reverse method and the mixed bed method.

[0003]

Since sucrose decomposes when the pH of the sucrose solution becomes acidic, desalting and purification of the sucrose solution must be performed so that the pH of the sucrose solution does not become acidic. Therefore, in the above desalination system combining an anion column using a strong basic anion exchange resin of the OH form and a mixed bed tower of an anion exchange resin of the OH form and a weakly acidic cation exchange resin of the H form, the sucrose solution is first used. After making the pH of the sucrose solution alkaline by contacting with an anion exchange resin in the form of OH, the mixture is contacted with a mixed bed resin of a strongly basic anion exchange resin and a weakly acidic cation exchange resin to perform purification.

However, in this method, the sugar solution becomes alkaline upon contact with a strongly basic anion exchange resin in the OH form, so that when a sugar solution containing a relatively large amount of hardness components such as calcium and magnesium is treated, In these cases, these hardness components precipitate as hydroxides or carbonate compounds and precipitate inside the resin layer, blocking the exchange groups of the ion exchange resin and causing a decrease in desalination performance. There were problems such as rising. Even in the reverse method, the same problem occurs because the treatment is performed by first contacting with a strong basic anion exchange resin.

In order to remove the deposited hardness component,
Normally, the strongly basic anion exchange resin in the anion exchange tower is regenerated using an acid such as hot HCl at a rate of once every 5 to 50 cycles. However, a stable treatment is unlikely to be performed because a hardness component or the like is deposited inside the resin layer for each liquid passage.

An object of the present invention is to provide a sucrose solution purifying apparatus capable of performing a stable desalting and purifying treatment and an efficient regeneration method of the apparatus.

[0007]

Means for Solving the Problems As a result of diligent research conducted by the present inventors, the above problem has been solved by providing a softening tower in the previous stage in a conventional desalination purification apparatus combining an anion tower and a mixed bed tower. Was found to be solved, and the present invention was completed.

That is, the present invention provides a softening tower filled with a cation exchange resin through which a sucrose solution flows, and an anion column filled with a strongly basic anion exchange resin through which a processing solution passed through the softening tower is provided. A sucrose liquid purifying apparatus characterized by comprising a mixed bed tower filled with a strongly basic anion exchange resin and a weakly acidic cation exchange resin through which the processing solution passed through the anion tower is passed, and a weak acidity of the mixed bed tower. After the acidic regeneration waste liquid of the cation exchange resin is passed through the cation exchange resin in the softening tower, the alkaline regeneration waste liquid of the strong basic anion exchange resin in the mixed bed tower and / or the alkaline regeneration waste liquid of the strong basic anion exchange resin in the anion tower 2. The method of claim 1, wherein the sucrose solution is passed through a cation exchange resin in a softening tower. The neutral regeneration waste liquid obtained by mixing the alkaline regeneration waste liquid of the strong basic anion exchange resin in the column and / or the alkaline regeneration waste liquid of the strong basic anion exchange resin in the anion tower is passed to the cation exchange resin in the softening tower. A method for regenerating a sucrose solution refining apparatus according to claim 1, wherein

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIG. 1, an apparatus for purifying a sucrose solution according to claim 1 of the present invention comprises an anion column 3 filled with a strongly basic anion exchange resin 4, a strongly basic anion exchange resin and a weakly basic anion exchange resin. A softening tower 1 filled with a cation exchange resin 2 is provided at the front stage of an apparatus including a mixed bed tower 5 filled with a mixed resin 6 of an acidic cation exchange resin. The cation exchange resin to be filled in the softening tower is not particularly limited as long as it can adsorb the hardness component in the sucrose solution, and a strongly acidic or weakly acidic cation exchange resin can be used. It is preferable because it has excellent performance of removing hardness components such as magnesium and magnesium. As the ionic form of the cation exchange resin, a sodium form is generally used, but a potassium form can also be used.

In order to purify a sucrose solution using the sucrose solution purifying apparatus of the present invention, a stock solution of a raw material sucrose solution is passed through the upper part of a softening tower 1 and, for example, a layer of a cation exchange resin 2 in a sodium form. , Hardness components such as calcium ions and magnesium ions in the stock solution are ion-exchanged and replaced with sodium ions. As a result, the sucrose solution after the softening treatment contains sodium salts such as NaCl and NaSO _4. Will be. The processing liquid flowing out from the lower part of the softening tower 1 is
The liquid flows through the upper part of the anion tower 3, passes through four layers of the strongly basic anion exchange resin in the OH form, is decolorized and deanionized, and flows out from the lower part. Hardness components such as calcium ions and magnesium ions in the undiluted solution are adsorbed and removed by the cation exchange resin 2 of the softening tower 1 in the former stage, so that the hardness components precipitate on the strongly basic anion exchange resin 4 of the anion tower 3. No accumulation. Anions such as Cl ions and SO ₄ ions contained in the sucrose solution after the softening treatment are replaced with OH ions by the OH type strong basic anion exchange resin 4 in the anion tower 3. The sucrose solution contains mainly NaOH. The treatment liquid flowing out from the lower part of the anion tower 3 is passed through the upper part of the mixed bed tower 5 and passes through six layers of a mixed resin layer of an OH type strongly basic anion exchange resin and an H type weakly acidic cation exchange resin. It is decolorized and desalted and flows out from the lower part of the mixed bed tower 5 as a purified sucrose solution. In the mixed bed tower 5, Na ions contained in the sucrose solution after the treatment with the anion tower 3, and cations such as calcium ions and magnesium ions tracely remaining in the sucrose solution are weakly acidic cation exchange resins. And a small amount of Cl and S remaining in the sucrose solution
Anions such as O ₄ ions are adsorbed and removed by the strongly basic anion exchange resin.

In the sucrose liquid purifying apparatus according to the first aspect of the present invention, the softening treatment is performed before the desalting treatment, whereby the hard component such as calcium and magnesium is deposited on the strong basic anion exchange resin in the anion tower. Accumulation can be prevented, and a decrease in desalination performance due to blocking of the exchange group of the strong basic anion exchange resin and an increase in pressure difference in the resin tower can be prevented.

The regeneration treatment of the sucrose solution purifying apparatus according to the first aspect of the present invention is performed after first separating the strongly basic anion exchange resin and the weakly acidic cation exchange resin in the mixed bed column by a difference in specific gravity.

As shown in FIG. 2, an acid regenerant such as an aqueous hydrochloric acid solution is first passed through the mixed bed tower 5 from the top of the mixed bed tower 5 after separation.
The regenerated waste liquid is discharged from the lower part, and is passed through the upper layer of the strongly basic anion exchange resin 7 and the lower layer of the weakly acidic cation exchange resin 8 in a lump. By the simultaneous passage of the acid regenerant, the weakly acidic cation exchange resin 8 in the mixed bed tower 5 is regenerated (formed into an H form), and the strongly basic anion exchange resin 7 is regenerated. The acidic regeneration waste liquid discharged from the mixed bed tower 5 is passed through the upper part of the anion tower 3 to carry out regenerating treatment of the strong basic anion exchange resin 4 in the anion tower 3. The acidic regeneration waste liquid discharged from the anion tower 3 is passed through the upper part of the softening tower 1 as a medicine. Thereby, a part of the cation exchange resin 2 of the softening tower 1 becomes the Na type, and the others become the H type. That is, when, for example, an aqueous hydrochloric acid solution was used as the acid regenerating agent, NaCl derived from Na desorbed from the weakly acidic cation exchange resin 8 of the mixed bed tower with hydrochloric acid in the acidic regeneration waste liquid was not used for the regeneration. Since it contains only excess hydrochloric acid and contains only a very small amount of other impurity ions such as Ca, when this is passed through the softening tower 1, a part of the cation exchange resin 2 becomes Na
Shape, others become H shape.

[0014] In the mixed bed tower 5 using the acid regenerating agent, the batch medicine is passed through the batch without separating the mixed resin of the strongly basic anion exchange resin and the weakly acidic cation exchange resin. May be separated by specific gravity to regenerate a strongly basic anion exchange resin described later.

Next, as shown in FIG. 3 (a), an alkaline regenerant such as an aqueous NaOH solution is passed through the upper part of the mixed bed tower 5, and water is simultaneously introduced from the lower part of the mixed bed tower 5 so that the waste liquid is recycled. The strongly basic anion exchange resin 7 in the mixed bed tower 5 is regenerated (OH form) by discharging from a collector (not shown) provided substantially in the middle of the ion exchange resin layer.

The alkaline regeneration waste liquid discharged from the mixed-bed column 5 is passed through the upper part of the softening column 1 to regenerate the H-type cation exchange resin in the cation exchange resin 2 into the Na type.

When the alkaline regeneration waste liquid is directly passed through the softening tower 1 without passing through the acidic regeneration waste liquid discharged from the mixed bed tower 5, calcium adsorbed on the cation exchange resin 2 in the softening tower 1 It is not preferable because ions and magnesium ions precipitate as hydroxides.

Further, as shown in FIG. 3 (b), an alkali regenerant is passed through the upper part of the anion tower 3 to regenerate (OH form) the strongly basic anion exchange resin 4. Usually, the amount of sodium necessary for the regeneration of the cation exchange resin 2 of the softening tower 1 is sufficiently contained in the alkaline regeneration waste liquid discharged during the regeneration of the strongly basic anion exchange resin 7 of the mixed bed tower 5, If the amount is insufficient, the alkaline regeneration waste liquid discharged from the anion tower 3 may be passed through the upper part of the softening tower 1 as a chemical.

In another embodiment of the regeneration method, when the acid regenerant is passed through the mixed bed tower 5, the strongly basic anion exchange resin and the weakly acidic cation exchange resin are separated by utilizing the specific gravity difference. The acid regenerating agent may be introduced from the lower part of the mixed bed tower 5, and the acid regenerating agent may be passed through the lower layer of the weakly acidic cation exchange resin 8 in the upward flow, and the acid regenerating waste liquid may be discharged from the collector.
In this case, at the same time, water is introduced from the upper part of the mixed bed tower 5, and the water is caused to flow downward through the upper layer of the strongly basic anion exchange resin 7 and discharged from the collector. However, in view of the ability to regenerate the strongly basic anion exchange resin, the above-mentioned regeneration method in which the acid regenerant is passed through at once is preferable.

The acid regeneration waste liquid discharged from the mixed bed tower 5 may be directly introduced into the softening tower 1 without being introduced into the anion tower 3. However, the method shown in FIG. 2 is preferable in that the regeneration treatment of the strongly basic anion exchange resin in the anion tower 3 can be performed.

In the method shown in FIGS. 3A and 3B, in order to make the cation exchange resin 2 of the softening tower 1 almost completely into Na form, the strong basic anion exchange resin 7 of the mixed bed tower 5 is used. An example in which an alkaline regeneration waste liquid and an alkaline regeneration waste liquid of the strongly basic anion exchange resin 4 of the anion tower 3 are used has been described. However, in the case where the cation exchange resin 2 of the softening tower 1 can be sufficiently made into the Na form by only one of them, Either one of the alkaline regeneration waste liquids may be used.

The acidic regeneration waste liquid discharged from the mixed bed tower 5 or the acidic regeneration waste liquid discharged by further passing the acidic regeneration waste liquid to the anion tower 3 is exchanged with the strongly basic anion exchange liquid in the mixed bed tower 5. The neutralized waste liquid obtained by mixing and / or neutralizing the alkaline regeneration waste liquid of the resin 7 and / or the alkaline regeneration waste liquid of the anion tower 3 is used.
May be used for the regeneration of the cation exchange resin 2.

Of course, the cation exchange resin 2 of the softening tower 1
Is replaced with a new regenerant (for example, aqueous sodium chloride solution)
May be used, but the chemical cost increases.

[0024]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to the examples.

Example 1 A raw sugar solution shown in Table 1 was treated with a strongly acidic cation exchange resin ("Amberlite IR-12" manufactured by Rohm and Haas Company).
OB ”) Softening column (softening tower) packed with 20 ml
And a strongly basic anion exchange resin (“Amberlite IRA-402BL” manufactured by Rohm and Haas) 4
An anion column (anion tower) filled with 0 ml and a strongly basic anion exchange resin (manufactured by Rohm and Haas Company,
"Amberlite IRA-402BL") and 40 ml of a weakly acidic cation exchange resin (manufactured by Rohm and Haas Company,
Using a mixed-bed column (mixed-bed column) filled with 20 ml of “Amberlite IRC-76”, the liquid passing temperature was 5%.
The liquid was passed through the operation of treating 2000 ml at 0 ° C. and a flow rate of 200 ml / h as one cycle.

In the regeneration treatment, a strongly basic anion exchange resin and a weakly acidic cation exchange resin in a mixed-bed column are first separated by utilizing a difference in specific gravity, and then 1N-H
Cl (160 ml) was passed through a mixed-bed column to regenerate a strongly basic anion exchange resin and regenerate a weakly acidic cation exchange resin. The acidic regeneration waste liquid was passed through a strongly basic anion exchange resin of an anion column to regenerate, and then passed through a strongly acidic cation exchange resin of a softening column.

Thereafter, 1N-NaOH (80 ml) was passed through the strongly basic anion exchange resin in the mixed bed type column to regenerate the strongly basic anion exchange resin, and the alkaline regenerated waste liquid was subjected to strong acidity in the softening column. The drug was passed through the cation exchange resin. Thereafter, the strongly basic anion exchange resin and the weakly acidic cation exchange resin in the mixed bed column were mixed so as to be uniform. Also, 1N-NaOH (80 ml) was added to the strongly basic anion exchange resin in the anion column after passing the acidic regeneration waste liquid.
The solution was regenerated by passing the solution through, and the alkaline regenerated waste liquid was passed through the strongly acidic cation exchange resin of the softening column.

By the above-described method, the operation of sucrose solution purification treatment-regeneration was repeated. Table 1 shows the properties of the softened sucrose solution at the fifth cycle.

[0029]

[Table 1]

As is evident from the results shown in Table 1, by performing the treatment with the sucrose solution purifying apparatus of the present invention, the hardness component can be removed in advance in the softening tower at the preceding stage, and the strength in the anion tower can be reduced. Since the hardness component in the sucrose solution does not precipitate and accumulate on the basic anion exchange resin, clogging due to the precipitation of the hardness component in the anion tower is eliminated, and the desorption of the dye and the ion exchange treatment are facilitated. As a result, stable processing performance can be obtained compared with the conventional processing system.

Further, it can be seen that the cation exchange resin of the softening tower can be sufficiently regenerated by the regeneration method of the present invention.

Comparative Example 1 A raw sugar solution shown in Table 1 was prepared by using a strongly basic anion exchange resin ("Amberlite IRA-" manufactured by Rohm and Haas Company).
402BL ") an anion column packed with 40 ml;
Strongly basic anion exchange resin (Rohm and Haas, "Amberlite IRA-402BL") 40 m
and a weakly acidic cation exchange resin (“Amberlite IRC-76”, manufactured by Rohm and Haas Co., Ltd.), and a mixed-bed column filled with the mixture.
The liquid was passed while the operation of treating 2000 ml at a flow rate of 200 ml / h at a temperature of 1 ° C. was defined as one cycle.

In the regeneration treatment, first, a strongly basic anion exchange resin and a weakly acidic cation exchange resin in a mixed bed type column are separated by utilizing a specific gravity difference, and then 1N-H
Cl (160 ml) was passed through the mixed bed column to regenerate the basic anion exchange resin and regenerate the weakly acidic cation exchange resin.

Thereafter, 1N-NaOH (80 ml) was passed through the strongly basic anion exchange resin in the mixed bed type column to regenerate the strongly basic anion exchange resin. Thereafter, the strongly basic anion exchange resin and the weakly acidic cation exchange resin in the mixed bed column were mixed so as to be uniform. Similarly, 1N-NaOH (8
0 ml).

The procedure of the sucrose solution purification treatment-regeneration treatment was repeated by the above method. In the third cycle, a hard component was deposited on the strongly basic anion exchange resin in the anion column so as to be visually confirmed.

[0036]

According to the apparatus for purifying sucrose solution of the present invention, it is possible to stably purify a sucrose solution without depositing a hard component on the strongly basic anion exchange resin of the anion tower. Further, according to the regeneration method of the present invention, the cation exchange resin of the softening tower can be regenerated by using the regeneration waste liquid of the mixed bed tower, so that the cation exchange resin is regenerated using, for example, a new salt solution. As compared with the above, the cost of the regenerated chemical can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a sucrose solution purifying apparatus of the present invention.

FIG. 2 is a flowchart showing a regeneration method using an acid regenerant in the regeneration method of the present invention.

FIG. 3 is a flow chart showing a regeneration method using an alkali regenerant among the regeneration methods of the present invention, wherein (a) shows regeneration of a strongly basic anion exchange resin in a mixed-bed column and regeneration of a cation exchange resin in a softening column. In the flow chart shown, (b) is a flow chart showing regeneration of a strongly basic anion exchange resin in an anion tower and regeneration of a cation exchange resin in a softening tower.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Softening tower 2 Cation exchange resin 3 Anion tower 4 Strongly basic anion exchange resin 5 Mixed bed tower 6 Mixed resin of strongly basic anion exchange resin and weakly acidic cation exchange resin 7 Strongly basic anion exchange resin 8 Weakly acidic cation exchange resin

Claims (3)

[Claims] 1. A softening tower filled with a cation exchange resin through which a sucrose solution flows, an anion tower filled with a strong basic anion exchange resin through which a processing solution passed through the softening tower passes, and an anion tower passing through the anion tower A sucrose liquid refining apparatus, comprising: a mixed bed tower filled with a strongly basic anion exchange resin and a weakly acidic cation exchange resin through which the treated liquid passes. 2. An acidic regeneration effluent of a weakly acidic cation exchange resin in a mixed bed tower is passed through a cation exchange resin in a softening tower, and then an alkaline regeneration waste liquor and / or anion tower of a strongly basic anion exchange resin in a mixed bed tower. 2. The method for regenerating an apparatus for purifying a sucrose solution according to claim 1, wherein the alkaline regenerated waste liquid of the strongly basic anion exchange resin is passed through a cation exchange resin in a softening tower. 3. An acidic regeneration waste liquid of a weakly acidic cation exchange resin in a mixed bed tower, an alkaline regeneration waste liquid of a strongly basic anion exchange resin in a mixed bed tower and / or an alkaline regeneration waste liquid of a strongly basic anion exchange resin in an anion tower. 2. The method for regenerating a sucrose liquid purifying apparatus according to claim 1, wherein a neutral regeneration waste liquid obtained by mixing the sucrose solution is passed through a cation exchange resin in a softening tower.