JPS6329993B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improvement in a method for regenerating resin used for removing bitterness or reducing acidity from citrus fruit juice. Conventionally, methods for recycling these resins generally involve the following steps. For example, in the case of synthetic adsorption resin for bitterness removal treatment, liquid passing → liquid extrusion → water removal →
Air stirring → water backwashing → water removal → air stirring → water backwashing → settling → caustic soda (chemical) injection → extrusion → water removal → hydrochloric acid solution (neutralization treatment) → air stirring → water removal → water backwashing → washing → water removal → Fruit juice liquid tension → liquid passage. However, the raw fruit juice contains pipes and viscous substances that get entangled with the resin during liquid passage and cause pressure loss, so it cannot be restored by simply backwashing with water, which is the usual method for regenerating ion exchange equipment. Even if the above-described steps of air agitation and water backwashing are repeated twice, the tangles of the resin cannot be easily loosened, and matted balls tend to form. When mud balls occur in the resin layer, the flow of the chemical solution becomes uneven, leading to insufficient regeneration and deterioration of performance. In the case of a purification apparatus in which a bitterening tower and an acid reducing tower are separately connected in series, this tendency becomes noticeable during resin regeneration in the first tower. The present invention completely loosens the tangles of the resin caused by the above-mentioned liquid passage when regenerating the purified resin of citrus fruit juice, restores a homogeneous resin layer, and improves the regeneration efficiency by injection and extrusion of chemical solutions. The purpose is to provide a reproduction method. That is, the regeneration method of the present invention is a method for regenerating a resin used for the bitterness removal treatment of citrus fruit juice using a synthetic adsorption resin or the acid reduction treatment using an anion exchange device, in which the resin is injected with chemicals into the resin before the treatment step by extrusion. The method is characterized in that after the resin is infiltrated into a caustic soda solution, air agitation and water backwashing are performed. The present invention takes advantage of the fact that pipes and viscous substances contained in citrus fruit juice that cause resin entanglement are relatively easily dissolved in a caustic soda solution. Before air agitation, approximately 3 to 10% NaOH is injected to about 100 mm above the surface of the resin layer to infiltrate it, and then air agitation and backwashing with water will loosen the resin and eliminate contamination. It can also be quickly washed to create a homogeneous resin layer. After that, when air agitation and water backwashing are repeated again, the clarification becomes much faster than when NaOH infiltration is not performed, and the resin layer becomes homogeneous, allowing regeneration operations beyond chemical injection to be performed smoothly. . Examples are shown below. Examples The regeneration of synthetic adsorption resins obtained by removing bitterness from fruit juice stock solutions was carried out in Examples using the method of the present invention and Comparative Examples using the conventional method described above. The bitterness removal tower used was one with a tower diameter of 200 mm and a height of 700 mm, and the inside of this tower was filled with synthetic adsorption resin to a height of 350 mm. The results were as shown in the table below.

【table】

[Table] In the case of the embodiment of the present invention, the resin layer is deposited evenly, so the following steps: chemical injection → extrusion → water removal → hydrochloric acid solution → air stirring → water removal → water backwashing → washing → water removal. While the regeneration operation was able to be carried out smoothly and efficiently, in the comparative example, that is, when the normal conventional method was used, some lumps remained at the bottom of the resin, and this caused difficulty in applying the chemical solution in the following regeneration process. This resulted in uneven flow and insufficient regeneration. Examples of the effects of the present invention as described above are as follows. ○B Stable regeneration can be achieved by uniform chemical injection. ○B The amount of backwash water used for pre-regeneration treatment can be saved by approximately 30%. ○C The pre-added caustic soda can be used for chemical injection, so there is no need to increase the amount of chemicals and there is almost no increase in equipment costs. ○D By reducing the amount of backwash water, the regeneration time can be slightly shortened.

Claims (1)

[Claims] 1. In a method for regenerating a resin used for de-bitterness treatment of citrus fruit juice with a synthetic adsorption resin or acid reduction treatment with an anion exchange resin, the resin is treated with a caustic soda solution before the treatment step of injecting chemicals into the resin and extrusion. A method for regenerating citrus fruit juice purification resin, which comprises infiltrating it into a liquid, followed by air agitation and water backwashing.