JP6265750B2 - Method and apparatus for purifying sucrose solution - Google Patents

Description

  The present invention relates to a purification method and a purification apparatus for a sucrose solution.

1. Purification of sucrose solution In the process of purifying sucrose at a refined sugar factory, the raw material sugar is dissolved in warm water, and then lime and carbonic acid are added to this to aggregate colloidal impurities into the fine crystals of calcium carbonate that are formed. Process. Subsequently, the sucrose solution after carbonation saturation treatment is subjected to decoloration treatment with bone charcoal or activated carbon after filtration, and after decoloration treatment with Cl-type anion exchange resin as final purification, it is crystallized into a product. In some factories, a sucrose crystal product or a liquid product is produced by performing a desalination treatment with an ion exchange resin in a sucrose purification process.

The ion exchange resin device for desalting sucrose solution includes (1) a single bed-single bed two-bed tower type device of reverse method, (2) mixed bed type device of mixed bed method, (3) A -A single-bed / mixed-bed two-bed tower type apparatus is known.
(1) In the reverse method two-bed tower type apparatus, the sucrose solution is treated with a single bed tower of OH type strongly basic anion exchange resin and then treated with a single bed tower of H type weak acid cation exchange resin. To desalinate.
(2) In the mixed bed type mixed bed apparatus, the sucrose solution is treated in a mixed bed tower in which an OH-type strongly basic anion exchange resin and an H-type weakly acidic cation exchange resin are mixed. Perform desalting.
(3) In the two-bed tower type apparatus of the A-MB method, the sucrose solution is treated with a single bed tower of OH type strong basic anion exchange resin, and then OH type strong basic anion exchange resin and H type weak The treatment is performed in a mixed bed column of acidic cation exchange resin (Patent Document 1).

However, in the purification apparatuses (1) to (3) above, the hardness component in the sucrose solution could not be sufficiently removed. Therefore, as shown below, a desalination apparatus in which a softening tower for removing hardness components is provided in the previous stage has been proposed.
(4) A desalination apparatus comprising a softening tower filled with a cation exchange resin and a two-bed tower type apparatus of the A-MB method disposed in the subsequent stage (Patent Document 2).

2. Regeneration of the sucrose solution purification device In addition, the regeneration of the ion exchange resin filled in the sucrose solution purification device involves passing an alkaline solution through a strongly basic anion exchange resin and passing an acid solution through a weakly acidic cation exchange resin. It is done by liquid. Regeneration of a mixed bed column packed with a strongly basic anion exchange resin and a weakly acidic cation exchange resin is carried out by separating the cation exchange resin and the anion exchange resin by their specific gravity difference, etc. Perform by replay. In Patent Document 3, first, an acid solution is introduced from the lower part of the tower, and the weakly acidic cation exchange resin and the weakly acidic cation exchange resin are separated simultaneously while fluidly regenerating the weakly acidic cation exchange resin in the tower. A way to do it is presented.

Japanese Patent No. 2785833 Japanese Patent Laid-Open No. 11-70000 Japanese Patent No. 3765653

1. Purification of sucrose solution The sucrose solution after carbonation saturation in the sucrose purification step contains a large amount of calcium ions (Ca ²⁺ ), carbonate ions (CO ₃ ²⁻ ), and bicarbonate ions (HCO ₃ ⁻ ). When such a sucrose solution is desalted using an OH-type strongly basic anion exchange resin, calcium ions are precipitated as carbonate (CaCO ₃ ) or hydroxide (Ca (OH) ₂ ), and the sucrose solution It causes degradation of quality and scaling to equipment. In particular, in the sucrose purification process that does not use bone charcoal having calcium adsorption ability, the calcium ion concentration in the sucrose solution becomes high, which is a problem.

  As a countermeasure against the above problems, as disclosed in Patent Document 2, there is a method of performing a softening treatment by disposing a softening tower for removing calcium ions in the previous stage of a desalting apparatus for a sucrose solution. is there. However, in these methods, in order to increase the number of softening towers, a total of three towers are required, and the initial introduction cost becomes high.

  In addition, sweet water is generated in the sucrose purification process. Sweet water is a low-concentration sucrose solution that is discharged from the desalinator during the initial flow when the sucrose solution is passed through a desalinator that has been previously filled with water, and the desalinator is washed after completion of purification. This represents a low-concentration sucrose solution discharged from the desalting apparatus. Generally, in order to increase the yield in the purification process, the sweet water is concentrated and then returned to the original process. Here, in the desalination apparatus which consists of three towers as mentioned above, the quantity of sweet water will increase by the part which the number of towers increased. Since concentration of sweet water requires energy and costs increase, it has been desired to reduce the amount of sweet water generated during the purification process.

2. Regeneration of the sucrose solution purification apparatus The apparatus described in Patent Document 3 discloses a method of separating two types of ion exchange resins in a mixed bed tower. However, there has been a demand for a method for efficiently regenerating a sucrose solution purification apparatus including a tower filled with an ion exchange resin for removing calcium ions. Moreover, since the refiner | purifier described in patent document 2 is comprised from three towers, the amount of drainage of a regenerated liquid tends to increase, and it was desired to reduce the amount of wastewater.

  The present invention has been made in view of the above problems, and firstly, the purification apparatus is constituted from two towers, and calcium ions and the like are removed in the first tower, thereby suppressing the precipitation of calcium and the like in the apparatus. Thus, the object is to obtain a high-purity sucrose solution while preventing scaling. Moreover, it aims at reducing cost while reducing the amount of sweet water and the amount of drainage.

  Secondly, the purpose is to reduce the amount of drainage of the regenerated liquid when regenerating the purification apparatus.

One embodiment is:
A first column packed with OH-type strongly basic anion exchange resin and Na-type or K-type cation exchange resin;
In the second tower arranged after the first tower and mixed and packed with OH type strong basic anion exchange resin and H type weak acid cation exchange resin,
Pass the sucrose solution in this order ,
The method for purifying a sucrose solution, wherein the first column is a mixed bed column in which the OH type strong basic anion exchange resin and the Na type or K type cation exchange resin are mixed and packed. About.

Other embodiments are:
A first column packed with OH-type strongly basic anion exchange resin and Na-type or K-type cation exchange resin;
A second tower disposed after the first tower and filled with an OH-type strongly basic anion exchange resin and an H-type weakly acidic cation exchange resin;
Have
The apparatus for purifying a sucrose solution, wherein the first column is a mixed bed column in which the OH type strong basic anion exchange resin and the Na type or K type cation exchange resin are mixed and packed. About.

  First, a purification apparatus is configured from two towers, and calcium ions and the like are removed in the first tower, so that precipitation of calcium and the like in the apparatus is suppressed to prevent scaling and a high-purity sucrose solution is obtained. be able to. In addition, the amount of sweet water and the amount of drainage can be reduced and the cost can be reduced.

  Secondly, when the refining apparatus is regenerated, the amount of drainage of the regenerated liquid can be reduced.

It is a schematic diagram showing the refiner | purifier of the sucrose solution of one Embodiment. It is a schematic diagram showing the refinement | purification apparatus of the sucrose solution of one reference form. It is a schematic diagram showing the purification method of the sucrose solution of one Embodiment. It is a schematic diagram showing the regeneration method of the refiner | purifier of the sucrose solution of one Embodiment. It is a figure showing the electrical conductivity of the sucrose solution of Example 1 and Comparative Examples 1 and 2. It is a figure showing pH of the sucrose solution of Example 1 and Comparative Examples 1 and 2. It is a figure showing the color value of the sucrose solution of Example 1 and Comparative Examples 1 and 2. It is a figure showing the light absorbency in 720 nm of the sucrose solution of Example 1 and Comparative Examples 1 and 2.

  Below, this invention is demonstrated based on embodiment. The following embodiment is an example of the present invention, and the present invention is not limited to the following embodiment.

(Sucrose solution purification equipment)
1 and 2 are schematic diagrams showing a sucrose solution purification apparatus. In the purification apparatus of FIG. 1, the first column 2 is a mixed bed column in which OH type strong basic anion exchange resin and Na type or K type cation exchange resin are mixed and packed, and the second column 4 is OH type strong basic anion exchange. It is a mixed bed tower in which an ion exchange resin and an H-type weakly acidic cation exchange resin are mixed and packed. In the refining apparatus of FIG. 2, the first column 2 has a multi-layered bed column in which an Na-type or K-type cation exchange resin 2a is arranged in the upper stage, and an OH type strongly basic anion exchange resin 2b is arranged in the lower stage. The column 4 is a mixed bed column of OH type strong basic anion exchange resin and H type weak acid cation exchange resin.

As shown in FIGS. 1 and 2, the first tower may be a mixed bed tower or a multi-layer bed tower. However, since the purity of the sucrose solution can be increased , the mixed bed tower is used in the present invention. Used . For reference, as shown in FIG. 2, when the first column is a multi-layered column, the upper (upstream) Na-type or K-type cation exchange resin and the lower (downstream) OH strong It is preferable to arrange a basic anion exchange resin. By arranging the ion exchange resin as shown in FIG. 2, it is possible to prevent the sucrose solution from becoming a high alkali (high pH) state upstream of the first tower, and to remove calcium ions and the like. Scaling can be prevented by suppressing the precipitation of calcium carbonate or the like in the refiner.

In the purification apparatus shown in FIGS. 1 and 2, the sucrose solution is softened (removal of calcium ions, etc.), anions are removed, and decolorized in the first tower 2. That is, a cation (calcium ion (Ca ²⁺ ) or the like) in the sucrose solution by the Na-type or K-type cation exchange resin of the first tower 2, and an anion in the sucrose solution by the OH-type strongly basic anion exchange resin ( Carbonate ions (CO ₃ ²⁻ ), hydrogen carbonate ions (HCO ₃ ⁻ ) and the like are adsorbed. Further, the dye in the sucrose solution is adsorbed by these ion exchange resins. For this reason, precipitation of calcium etc. in a refiner | purifier can be suppressed and scaling can be prevented. Accordingly, it is possible to obtain a high-purity sucrose solution by suppressing the desalting ability of the purification apparatus from being reduced by precipitation or scaling of calcium or the like. Further, conventionally, since a single tower for softening the sucrose solution was provided, it was necessary to provide a purification apparatus consisting of a total of three towers, whereas in this embodiment, the sucrose solution was composed of two towers. Can be purified (desalted and decolorized). Therefore, the space for installing the apparatus can be reduced, and the amount of sweet water and the amount of drainage generated in the refining process can be reduced, thereby reducing the cost.

  Furthermore, the sucrose solution contains anionic impurities such as amino acids, organic acids, and polysaccharides in addition to pigments and inorganic ions. These anionic impurities may form complexes with cations such as calcium ions. Even if the sucrose solution containing this complex is passed through a purification apparatus having a single column for softening and a single column filled with an anion exchange resin, calcium ions and the like do not dissociate from the complex. In this tower, calcium ions and the like cannot be removed. In contrast, in the purification apparatus of the present embodiment, the first column 2 is filled with both OH-type strongly basic anion exchange resin and Na-type or K-type cation exchange resin. . For this reason, since anion impurities are adsorbed on the OH-type strongly basic anion exchange resin, calcium ions and the like in the complex are liberated. The liberated calcium ions and the like are adsorbed on the Na-type or K-type cation exchange resin. Therefore, even when the sucrose solution contains anionic impurities, it can be effectively removed in the first tower 2 and the sucrose solution can be made highly pure.

Further, the H-type weakly acidic cation exchange resin in the second column 4 adsorbs sodium ions (Na ⁺ ) or potassium ions (K ⁺ ) that have been desorbed by adsorption of calcium ions (Ca ²⁺ ) or the like in the first column 2. Then, carbonate ions (CO ₃ ²⁻ ), hydrogen carbonate ions (HCO ₃ ⁻ ), etc. that could not be removed by the first tower 2 with the OH type strongly basic anion exchange resin are adsorbed. Further, the sucrose solution can be decolorized in the second tower 4.

  The type of the OH type strong basic anion exchange resin charged in the first tower 2 and the second tower 4 is not particularly limited, but the first tower 2 includes an acrylic OH type strong basic anion exchange resin, the second tower. 4 is preferably filled with a styrenic OH type strongly basic anion exchange resin. Usually, the sucrose solution contains a dye, but the acrylic OH-type strongly basic anion exchange resin has a characteristic that the affinity with the dye is low and the adsorptive power with the dye is weak. On the other hand, the styrenic OH type strongly basic anion exchange resin has a high affinity with a dye and a strong adsorbing power with the dye. Here, the pigments contained in the sucrose solution exist from those having a high adsorption power to the ion exchange resin to those having a low adsorption power.

  Accordingly, the acrylic OH-type strongly basic anion exchange resin mainly absorbs a dye having a high adsorbing power with the ion exchange resin. Since the acrylic OH type strongly basic anion exchange resin originally has a weak adsorption power with the dye, the dye adsorbed on the ion exchange resin can be easily detached from the ion exchange resin by the regenerant. As a result, the acrylic OH type strongly basic anion exchange resin can be regenerated and used without deteriorating.

  In addition, as described above, the first tower 2 mainly absorbs a dye having a high adsorbing power with the ion exchange resin. Therefore, the remaining in the sucrose solution after passing through the first tower 2 is mainly It becomes a dye having a low adsorption power with the ion exchange resin. For this reason, the styrenic OH type strongly basic anion exchange resin in the second column 4 mainly adsorbs a dye having a low adsorption power with the ion exchange resin. Therefore, even a dye adsorbed on a styrene-based OH type strongly basic anion exchange resin having a high adsorbing power with the dye can be easily detached by the regenerant. As a result, the styrenic OH type strongly basic anion exchange resin can be regenerated and used without deteriorating.

  As described above, the first column 2 is filled with acrylic OH type strongly basic anion exchange resin, and the second column 4 is filled with styrene type OH type strongly basic anion exchange resin. The sucrose solution can be desalted with high capacity without deteriorating the resin by decolorization (dye adsorption).

  Examples of the acrylic OH type strongly basic anion exchange resin charged in the first tower 2 include Amberlite (registered trademark, hereinafter the same) IRA958, IRA458 (manufactured by Dow Chemical Co., Ltd.), PUROLITE (registered trademark, hereinafter, the same). ) A860, A850 (manufactured by Purolite) and the like. Of the acrylic OH type strongly basic anion exchange resins, the gel type resin is particularly advantageous because it has a large exchange capacity and increases the amount of sucrose solution that can be processed. Examples of the gel-type acrylic strongly basic anion exchange resin include Amberlite IRA458 (manufactured by Dow Chemical Co.) and PUROLITE A850 (manufactured by Purolite).

  The Na-type or K-type cation exchange resin charged in the first tower 2 may be a strong acid cation exchange resin or a weak acid cation exchange resin. Examples of Na-type strongly acidic cation exchange resins include Amberlite IR120B Na, IR124 Na, 200CT Na, 252 Na (manufactured by Dow Chemical Company), Diaion (registered trademark, hereinafter the same) SK1B, PK216 (manufactured by Mitsubishi Chemical Corporation) ), PUROLITE C100E (manufactured by Purolite). Alternatively, a known H-type strongly acidic cation exchange resin converted into a Na-type or K-type strongly acidic cation exchange resin by regenerating with a regenerating agent such as NaOH or KOH may be used. Similarly, a known H-type weakly acidic cation exchange resin converted into a Na-type or K-type weakly acidic cation exchange resin by regenerating with a regenerating agent such as NaOH or KOH may be used.

  Examples of the styrenic strongly basic anion exchange resin charged in the second column 4 include Amberlite IRA900, IRA402, IRA402BL (Dow Chemical), PUROLITE A500S (Purolite), Diaion SA10A, PA308 (Mitsubishi). Chemicals).

  Moreover, as weakly acidic cation exchange resin used for the 2nd tower 4, for example, Amberlite IRC76, Dowex (registered trademark, hereinafter the same) MAC-3 (manufactured by Dow Chemical Co.), PUROLITE C115E (manufactured by Purolite) And Diaion WK10, WK11 (manufactured by Mitsubishi Chemical Corporation), and the like.

(Purification method of sucrose solution)
FIG. 3 is a schematic diagram showing a method for purifying a sucrose solution using the purification apparatus of FIG. In this purification method, the sucrose solution is passed through in the direction of the arrow in the figure, the sucrose solution is first passed through the first tower 2, and the sucrose solution after passing through the first tower 2 is passed through the second tower 2. 4 is passed through. In the Na-type or K-type cation exchange resin of the first tower 2, a cation (calcium ion Ca ²⁺ or the like) in the sucrose solution, and in the OH type strongly basic anion exchange resin, an anion (carbonate ion (CO ₃ ²⁻ ) And hydrogen carbonate ions (HCO ₃ ⁻ ) and the like. Moreover, the dye in a sucrose solution can be adsorbed by these ion exchange resins. Accordingly, the precipitation of calcium or the like in the first column 2 is suppressed to prevent scaling in the purification apparatus, and the decrease in the demineralization ability of the first column 2 is thereby suppressed, thereby desalting and decolorization. A high-purity sucrose solution can be obtained. Moreover, compared with the conventional refiner | purifier, while being able to reduce the space which installs an apparatus, the quantity of the sweet water and drainage amount which arise in a refinement | purification process can be reduced, and cost can be reduced. Further, when a complex such as anion impurities and calcium ions is contained in the sucrose solution, by passing the sucrose solution through the first tower 2, an OH-type strongly basic anion is obtained from the complex. Since anion impurities are adsorbed on the exchange resin, calcium ions and the like are liberated. Since the liberated calcium ions and the like are adsorbed on the Na-type or K-type strongly acidic cation exchange resin, the complex can be effectively removed in the first column 2 and the sucrose solution can be made highly pure.

In addition, in the H-type weakly acidic cation exchange resin of the second column 4, sodium ions (Na ⁺ ) or potassium ions (K ⁺ ) desorbed by adsorption of calcium ions (Ca ²⁺ ) and the like in the first column 2 are ^removed. The OH-type strongly basic anion exchange resin removes carbonate ions (CO ₃ ²⁻ ), bicarbonate ions (HCO ₃ ⁻ ), etc. remaining in the sucrose solution even after passing through the first column 2. . Further, the sucrose solution can be decolorized in the second tower 4.

  The sucrose solution used for purification is not particularly limited, but is a filtrate obtained after carbonation saturation treatment and filtration treatment, a solution obtained by further performing activated carbon treatment after the filtration treatment, or a solution from which impurities have been removed by other treatment. Preferably there is. These sucrose solutions contain a large amount of impurities such as calcium ions and magnesium ions. Therefore, a high-purity sucrose solution can be obtained by purifying these sucrose solutions with the purification apparatus of this embodiment. The sucrose solution before passing through the first tower 2 preferably has a sum of calcium ion and magnesium ion concentrations of 0.001 mol / L or more, more preferably 0.002 mol / L or more. preferable. In the present embodiment, even a sucrose solution containing high concentrations of calcium ions and magnesium ions as described above, these ions are effectively removed in the first tower 2 to obtain a high-purity sucrose solution. be able to.

(Regeneration method of sucrose solution purification equipment)
4A to 4D are schematic views showing a method for regenerating the purification apparatus of FIG. By refinement of the sucrose solution, Na ions (Na ⁺ ) or K ions (K ⁺ ) are desorbed from the Na-type or K-type cation exchange resin in the first tower 2, mainly calcium ions (Ca ²⁺ ), etc. Adsorbs. Hydroxide ions (OH ⁻ ) are desorbed from the OH type strongly basic anion exchange resin in the first tower 2, and mainly carbonate ions (CO ₃ ²⁻ ), bicarbonate ions (HCO ₃ ⁻ ) and chloride. Object ions (Cl ⁻ ) and the like are adsorbed. In addition, hydrogen ions (H ⁺ ) and hydroxide ions (OH ⁻ ) are desorbed from the H-type weakly acidic cation exchange resin and the OH-type strongly basic anion exchange resin in the second column 4 respectively. Na ions (Na ⁺ ) or K ions (K ⁺ ), carbonate ions (CO ₃ ²⁻ ), and bicarbonate ions (HCO ₃ ⁻ ) are adsorbed on the surface. That is, after purification of the sucrose solution, OH-type strongly basic anion exchange resin in the first column 2 is mainly CO 3 ^_2-- strong basic anion exchange resin, HCO 3 _- ^- strong basic anion exchange resin And Cl ⁻ -strongly basic anion exchange resin, and Na-type or K-type cation exchange resin is mainly Ca ²⁺ -cation exchange resin or the like. Further, after purification, the H-form weakly acidic cation exchange resin in the second column 4 mainly becomes Na ⁺ -weakly acidic cation exchange resin or K ⁺ -weakly acidic cation exchange resin, and the OH-type strongly basic anion. exchange resin is mainly CO 3 ^_2-- has a strong basic anion exchange resin _- strong basic anion exchange resin and HCO 3 ^-.

In the regeneration method of the present embodiment, first, as shown in FIG. 4A, the first regeneration solution for the H-type weakly acidic cation exchange resin is passed through the second column 4. At this time, the first regenerating liquid flows from the bottom of the second tower 4 toward the top. Thereby, the strongly basic anion exchange resin and the weakly acidic cation exchange resin in the second column 4 flow and are separated by the difference in specific gravity of these ion exchange resins. In the present embodiment, a strong basic anion exchange resin 4a is arranged at the upper part and a weak acidic cation exchange resin 4b is arranged at the lower part in the second tower 4 by the separation. Moreover, Na ion (Na ⁺ ) or K ion (K ⁺ ) is desorbed and regenerated from the weakly acidic cation exchange resin in the second column 4 by the first regeneration solution, and the H-type weakly acidic cation exchange resin is regenerated. It becomes.

Next, the first regenerated liquid is recovered from the top of the second tower 4 and passed from the top of the first tower 2 toward the bottom. At this time, since the first regenerating liquid flows from the bottom to the top of the second column 4, it is not necessary to flow a solution such as water so as to be countercurrent to the first regenerating liquid. Therefore, it can be recovered from the second column 4 without reducing the concentration of the first regenerated solution with water or the like. By passing the first regeneration solution through the first column 2, calcium ions (Ca ²⁺ ) and the like adsorbed on the cation exchange resin in the first column 2 are desorbed, and instead hydrogen ions (H ⁺ ) Is adsorbed to form an H-type cation exchange resin.
The first regeneration solution is not particularly limited as long as it is an acid solution, and is preferably an aqueous hydrochloric acid solution. The hydrochloric acid concentration in the aqueous hydrochloric acid solution is not particularly limited as long as it does not degrade the ion exchange resin, but is preferably 0.05 to 2.0 N, more preferably 0.1 to 1.0 N. As described above, when an aqueous hydrochloric acid solution is used as the first regeneration liquid, carbonate ions (CO ₃ ²⁻ ) and hydrogen carbonate ions (HCO ₃ ⁻ ) are passed through the second tower 4 after passing the first regeneration liquid. ) Are adsorbed by chloride ions (Cl ⁻ ) by desorbing carbonate ions (CO ₃ ²⁻ ) and bicarbonate ions (HCO ₃ ⁻ ) from the strongly basic anion exchange resin in the second tower 4. , Cl ⁻ -strongly basic anion exchange resin. Similarly, after passing the first regenerating solution into the first column 2, the strongly basic anion in which carbonate ions (CO ₃ ²⁻ ) and bicarbonate ions (HCO ₃ ⁻ ) in the first column 2 are adsorbed. The ion exchange resin becomes a Cl ⁻ -strongly basic anion exchange resin.

  Further, in the above process, the strongly basic anion exchange resin in the first column 2 and the second column 4 is regenerated. That is, this regeneration removes impurities (such as dyes) adsorbed on the base structure of the strongly basic anion exchange resin.

Next, as shown in FIG. 4B, a second regeneration solution for OH type strongly basic anion exchange resin containing sodium ions or potassium ions is passed from the top of the second column 4 and second Water is passed from the bottom of the tower 4. By making this water counter-current with the second regeneration solution, the second regeneration solution reaches the H-type weakly acidic cation exchange resin separated at the lower part in the second column 4 and the H-type weakness is reached. It is possible to prevent the ionic form of the acidic cation exchange resin from being converted to the Na form or the K form. By passing the second regeneration solution through the second column 4, chloride ions (Cl ⁻ ) are desorbed from the strongly basic anion exchange resin in the second column 4, and instead hydroxide ions ( OH ⁻ ) is adsorbed to obtain an OH-type strongly basic anion exchange resin.

As shown in FIG. 4B, the second regenerated solution and water passed through the second column 4 as described above are separated from each other as OH-type strongly basic anion exchange resin and H-type weakly acidic cation. Collect with an intermediate collector located at the boundary of the exchange resin. Next, the second regenerated liquid and water that have passed through the second tower 4 are passed from the top of the first tower 2 toward the bottom. Thus, strongly basic anion exchange resin in the first column 2 is rough play, a part of the chloride ion (Cl ^-) was desorbed, hydroxide ions instead - adsorb ^(OH) OH type strongly basic anion exchange resin. At the same time, the hydrogen ions (H ⁺ ) of the H-type cation exchange resin in the first column 2 are desorbed, and sodium ions (Na ⁺ ) or potassium ions (K ⁺ ) are adsorbed instead. Na-type or K-type cation exchange resin. The second regenerating solution is not particularly limited as long as it is an alkaline solution containing sodium ions or potassium ions, preferably a sodium hydroxide aqueous solution or a potassium hydroxide aqueous solution, more preferably a sodium hydroxide aqueous solution. Is good. Although the sodium hydroxide density | concentration in sodium hydroxide aqueous solution will not be specifically limited if it does not degrade an ion exchange resin, 0.05-3.0 normal is preferable and 0.5-2.0 normal is more preferable.

Next, as shown in FIG. 4C, a third regeneration solution for OH type strongly basic anion exchange resin is passed from the top to the bottom of the first column 2. Thereby, carbonate ions (CO ₃ ²⁻ ), hydrogen carbonate ions (HCO ₃ ⁻ ), and chloride ions (Cl ⁻ ) adsorbed on a part of the strongly basic anion exchange resin in the first column 2. Is removed, and instead hydroxide ions (OH ⁻ ) are adsorbed to form an OH-type strongly basic anion exchange resin. The third regenerating solution is not particularly limited as long as it is an alkaline solution, but preferably the same as the second regenerating solution.

  Next, as shown in FIG. 4D, compressed air is allowed to flow from the bottom of the second column 4 into the second column 4, and the OH type strong basic anion exchange resin and the H type separated and arranged in the second column 4. A weakly acidic cation exchange resin is flowed and mixed. Thus, in the second tower 4 after the inflow of compressed air is completed, the OH-type strongly basic anion exchange resin and the H-type weakly acidic cation exchange resin are mixed and packed, and the second tower 4 becomes a mixed bed.

  In the above regeneration method, it is not necessary to flow a solution such as water in the step of FIG. 4A. In addition, the amount of regenerated liquid can be reduced as compared with the case of regenerating a conventional three-column purification apparatus.

  After passing the regenerated liquid through each tower, water is passed through each tower, and the regenerated liquid remaining in each tower is pushed out and discharged out of the tower. Moreover, after the process of FIG. 4D, water may be passed through each tower to wash the ion exchange resin in the tower. Since the purification apparatus of this embodiment consists of two towers, the amount of water used in the above process can also be reduced compared to a purification apparatus consisting of three towers. In the above embodiment, the process of FIG. 4D is performed after the process of FIG. 4C. However, the process of FIG. 4C may be performed after the process of FIG. 4D, or the processes of FIGS. 4C and 4D may be performed simultaneously. good.

Example 1
As the sucrose solution, a solution obtained by subjecting the filtrate after carbonation saturation treatment and filtration treatment to activated carbon treatment (Brix sugar content 55%, conductivity 250 μS / cm, color value 80 ICUMSA, Abs720 0.002 (100 mm cell) Measurement)). This sucrose solution was passed through the purification apparatus of FIG. 1 in the order of the first column 2 and the second column 4 at 50 ° C. and 300 mL / h. Then, the conductivity, pH, color value, and turbidity (absorbance at 720 nm) of the sucrose solution at the outlet of the second tower 4 were monitored. For the first column 2 and the second column 4, ion exchange resins shown in Table 1 below were used.

  Next, 500 mL of a 0.5 N aqueous hydrochloric acid solution (first regeneration solution) was passed from the bottom of the second column 4 toward the top at 800 mL / h. As a result, Amberlite IRC76 and 402BL were flowed in the second tower 4 to separate the Amberlite IRA402BL in the upper part of the second tower 4 and the Amberlite IRC76 in the lower part. Thereafter, the waste liquid (first regenerated liquid) discharged from the top of the second tower 4 was passed from the top of the first tower 2 toward the bottom. Subsequently, 300 mL of pure water was allowed to flow into the second tower 4 at the same flow rate, and the aqueous hydrochloric acid solution in the tower was extruded. Subsequently, 800 mL of pure water was poured into the second tower 4 to wash the ion exchange resin in the tower.

  Next, 150 mL of 2N aqueous sodium hydroxide solution (second regeneration solution) is flowed from the top of the second column 4 at 400 mL / h, and at the same time, pure water is flowed from the bottom of the second column 4 at 400 mL / h. Washed away. The waste liquid (second regenerated liquid and pure water) extracted from the intermediate collector located at the boundary between Amberlite IRA402BL and Amberlite IRC76 was passed through the first tower 2. Thereafter, 200 mL of pure water was passed through the top and bottom of the second column 4 at 400 mL / h, and sodium hydroxide remaining in the second column 4 was extruded. Next, 1200 mL of pure water was allowed to flow from the top of the second column 4 at a flow rate of 800 mL / h and discharged from the bottom of the second column 4. Thereafter, compressed air was introduced from the bottom of the second tower 4, and Amberlite IRA402BL and Amberlite IRC76 were mixed to form a mixed bed again.

  Next, 100 mL of a 1N aqueous sodium hydroxide solution (third regeneration solution) was passed through the top of the first column 2 at 400 mL / h and discharged from the bottom of the first column 2. Next, after 200 mL of pure water is flowed into the first tower 2 at the same flow rate to extrude sodium hydroxide in the first tower 2, 1200 mL of pure water is flowed into the first tower 2 at 800 mL / h, and the final washing is performed. Carried out.

  The purification of the sucrose solution and the regeneration of the purification apparatus were repeated three times as one cycle. The types of ion exchange resins used in the first column 2 and the second column 4 are shown in Table 1, and the results of the third cycle are shown in FIGS.

(Example 2)
As the sucrose solution, a solution obtained by subjecting the filtrate after carbonic acid saturation treatment and filtration treatment to activated carbon treatment (Brix sugar content 55%, conductivity 300 μS / cm, color value 725 ICUMSA) was used. This sucrose solution was passed through the purification apparatus of FIG. 1 in the same manner as in Example 1 at a total volume of 3.6 L at 50 ° C. and 300 mL / h. The whole amount of the sucrose solution after the purification treatment was recovered, and the conductivity, pH, and color value were measured. Next, the purification apparatus of FIG. 1 was regenerated in the same manner as in Example 1. The purification of the sucrose solution and the regeneration of the purification apparatus were repeated 20 times as one cycle. Table 2 shows the types of ion exchange resins used in the first column 2 and the second column 4, and Table 3 shows the results of the 1st cycle, 10th cycle, and 20th cycle. Table 4 shows the measurement results of the exchange capacity of each ion exchange resin before and after use (new and after 20 cycles).

(Example 3)
The sucrose was prepared in the same manner as in Example 2 except that the acrylic strongly basic anion exchange resin (Amberlite IRA458) shown in Table 2 was used as the strongly basic anion exchange resin in the first tower 2 of FIG. Purification of the solution and regeneration of the purification apparatus were performed. The ion exchange resins used in the first column 2 and the second column 4 are shown in Table 2, and the results of the 1st cycle, 10th cycle, and 20th cycle are shown in Table 5. Table 6 shows the measurement results of the exchange capacity of each ion exchange resin before and after use (new product and after 20 cycles).

(Comparative Example 1)
As shown in Table 1, the sucrose solution was purified in the same manner as in Example 1 except that Na-type cation exchange resin (Amberlite IR120B) was not used in the first column 2 of FIG. .

The regeneration of the ion exchange resin in the first column 2 and the second column 4 was performed separately.
The regeneration of the ion exchange resin in the second tower 4 was performed as follows. 500 mL of 0.5 N hydrochloric acid aqueous solution was passed through the bottom of the second column 4 at 800 mL / h. As a result, Amberlite IRC76 and IRA402BL were flowed in the second tower 4 to separate Amberlite IRA402BL in the upper part of the second tower 4 and Amberlite IRC76 in the lower part. Subsequently, 300 mL of pure water was allowed to flow into the second column 4 at the same flow rate, and hydrochloric acid in the column was extruded. Subsequently, 800 mL of pure water was poured into the second tower 4 to wash the ion exchange resin in the tower.

  Next, 150 mL of 1N sodium hydroxide aqueous solution was flowed from the top of the second column 4 at 400 mL / h, and at the same time, pure water was flowed from the bottom of the second column 4 at 400 mL / h. Waste liquid was discharged from an intermediate collector located at the boundary between Amberlite IRA402BL and Amberlite IRC76. Thereafter, 200 mL of pure water was passed through the top and bottom of the second column 4 at 400 mL / h, and sodium hydroxide remaining in the second column 4 was extruded. Next, 1200 mL of pure water was allowed to flow from the top of the second column 4 at a flow rate of 800 mL / h and was discharged from the bottom of the second column 4. Thereafter, compressed air was introduced from the bottom of the second tower 4, and Amberlite IRA402BL and Amberlite IRC76 were mixed to form a mixed bed again.

  The regeneration of the ion exchange resin in the first tower 2 was performed as follows. From the top of the first column 2, 300 mL of a 1N aqueous sodium hydroxide solution was passed at 400 mL / h and discharged from the bottom of the first column 2. Next, after 200 mL of pure water is flowed into the first tower 2 at the same flow rate to extrude sodium hydroxide in the first tower 2, 1200 mL of pure water is flowed into the first tower 2 at 800 mL / h, and the final washing is performed. Carried out.

  The purification of the sucrose solution and the regeneration of the purification apparatus were repeated three times as one cycle. The types of ion exchange resins used in the first column 2 and the second column 4 are shown in Table 1, and the results of the third cycle are shown in FIGS.

(Comparative Example 2)
As shown in Table 1, the Na-type cation exchange resin (Amberlite IR120B) is not used in the first column 2 of FIG. A softening tower filled with light IR120B) was provided. Except for this, the sucrose solution was purified in the same manner as in Example 1.

  The regeneration of the ion exchange resin in the first column 2 and the second column 4 was performed in the same manner as in Comparative Example 1. Amberlite IR120B in the first-stage softening tower was regenerated as follows. First, 100 mL of a 10 mass% NaCl aqueous solution was passed through the top of the softening tower at 200 mL / h and discharged from the bottom. Thereafter, 50 mL of pure water was flowed into the softening tower at the same flow rate, and 400 mL of pure water was passed through the softening tower at 400 mL / h to wash Amberlite IR120B.

  The purification of the sucrose solution and the regeneration of the purification apparatus were repeated three times as one cycle. The types of ion exchange resins used in the first column 2 and the second column 4 are shown in Table 1, and the results of the third cycle are shown in FIGS.

  From the results of FIGS. 5 to 8, it can be seen that the conductivity, color value, and absorbance at 720 nm are greatly reduced in Example 1 as compared with Comparative Example 1. From the results of Example 1 and Comparative Example 2, the two-column purification apparatus (Example 1) achieved the same conductivity, color value, and absorbance at 720 nm as the three-column purification apparatus (Comparative Example 2). I understand that I can do it. Furthermore, the amount of sweet water having a Brix sugar content of 2 to 30% generated in the purification process was 450 mL in Comparative Example 2 whereas it was 360 mL in Example 1, and the amount of sweet water was reduced by 20%. We were able to.

  Further, from the results of Tables 3 and 5, it can be seen that in Examples 2 and 3, the pH of the sucrose solution hardly changed even after 20 cycles, and a sucrose solution having low conductivity and color value was obtained. Although the color value slightly increases as the number of cycles increases, the increase in color value is smaller in Example 3 than in Example 2, and the acrylic anion exchange resin is used in the first column. It can be seen that the rate of deterioration of the ion exchange resin becomes moderate.

  From the results in Tables 4 and 6, when an acrylic anion exchange resin (Amberlite IRA458) was used in the first tower of Example 3, the acrylic anion exchange resin in the first tower was converted to a dye or the like. Since it is hard to be contaminated, it can be seen that a decrease in the total exchange capacity after use can be significantly suppressed as compared with the styrene-based anion exchange resin (Amberlite IRA402BL) in the first column in Example 2. Furthermore, for the styrene anion exchange resin (Amberlite IRA402BL) in the second tower, Example 3 using an acrylic anion exchange resin in the first tower used a styrene anion exchange resin in the first tower. It turns out that the fall of the total exchange capacity | capacitance after use can be suppressed compared with Example 2. FIG.

2 First column 2a Na-type or K-type cation exchange resin 2b OH type strongly basic anion exchange resin 4 Second column 4a Strongly basic anion exchange resin 4b Weakly acidic cation exchange resin

Claims (8)

A first column packed with OH-type strongly basic anion exchange resin and Na-type or K-type cation exchange resin;
In the second tower arranged after the first tower and mixed and packed with OH type strong basic anion exchange resin and H type weak acid cation exchange resin,
Pass the sucrose solution in this order ,
The method for purifying a sucrose solution, wherein the first column is a mixed bed column in which the OH type strong basic anion exchange resin and the Na type or K type cation exchange resin are mixed and packed. . The OH type strong basic anion exchange resin packed in the first tower is an acrylic OH type strong basic anion exchange resin,
The method for purifying a sucrose solution according to claim 1 , wherein the OH-type strongly basic anion exchange resin packed in the second tower is a styrene-type OH-type strongly basic anion exchange resin. The method for purifying a sucrose solution according to claim 1 or 2 , wherein the sucrose solution before passing through the first tower has a sum of calcium ions and magnesium ions of 0.001 mol / L or more. . After passing the sucrose solution through the first and second towers,
Passing the first regeneration solution for the H-type weakly acidic cation exchange resin through the second column;
Passing the first regenerated liquid after passing through the second tower through the first tower;
Passing a second regeneration solution for OH type strongly basic anion exchange resin containing sodium ions or potassium ions into the second column;
Passing the second regenerated solution after passing through the second column through the first column;
The method for purifying a sucrose solution according to any one of claims 1 to 3 , wherein the sucrose solution is contained in this order. In the step of passing the first regenerating liquid into the second tower,
Claims wherein in the second column was passed through a first regenerant, characterized in that to separate from each other by a strongly basic anion exchange resins and weakly acidic cation exchange resin to flow in the second the column Item 5. A method for purifying a sucrose solution according to Item 4 . The method for purifying a sucrose solution according to claim 4 or 5 , further comprising a step of passing a third regenerating solution for OH type strongly basic anion exchange resin through the first column. . A first column packed with OH-type strongly basic anion exchange resin and Na-type or K-type cation exchange resin;
A second tower disposed after the first tower and filled with an OH-type strongly basic anion exchange resin and an H-type weakly acidic cation exchange resin;
Have
The apparatus for purifying a sucrose solution, wherein the first column is a mixed bed column in which the OH type strong basic anion exchange resin and the Na type or K type cation exchange resin are mixed and packed. . The OH type strong basic anion exchange resin packed in the first tower is an acrylic OH type strong basic anion exchange resin,
8. The apparatus for purifying a sucrose solution according to claim 7 , wherein the OH type strongly basic anion exchange resin packed in the second tower is a styrene type OH type strongly basic anion exchange resin.