JP2014188516A - Slightly acidic electrolytic water generation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide, in acknowledgment of the fact that a method for manufacturing slightly acidic electrolytic water endowed with a bactericidal activity by electrolyzing hydrochloric acid entails a pH loss due to a generated chlorine content, above all an abnormally low pH in the case of soft water, a slightly acidic electrolytic water production technique affording a high utility convenience and not yielding an abnormally low pH even in a case where a body of diluted water having a low hardness is used.SOLUTION: The problem is solved by using a dilute hydrochloric acid having been diluted with a body of mineral content-containing water such as deep oceanic water, mineral water, etc.

Description

The present invention relates to a method for producing slightly acidic electrolyzed water having sterilizing power by electrolyzing hydrochloric acid and diluting an electrolysis solution with water.

A conventional method for producing slightly acidic electrolyzed water having sterilizing power by electrolyzing hydrochloric acid is to electrolyze hydrochloric acid containing no salt (Japanese Patent Application No. 8-309920).

In this method, only hydrochloric acid is electrolyzed in a non-diaphragm electrolytic cell, and a reaction such as 2Cl ⁻ → Cl ₂ + 2e ^{− on} the anode and 2H ⁺ + 2e ⁻ → H _{2 on} the cathode occurs.
That is, chlorine and hydrogen are generated. Hydrogen escapes into the air as it is, but chlorine immediately reacts with water as Cl ₂ + H ₂ O → HOCl + HCl to produce hypochlorous acid and hydrochloric acid in the same mole as chlorine. This hypochlorous acid is the main sterilizing agent, but hydrochloric acid generated at the same time lowers the pH of the solution.

In the conventional method for producing slightly acidic electrolyzed water having sterilizing power by electrolyzing hydrochloric acid as described above, the pH is lowered by the generated hydrochloric acid, but a sufficient amount of hardness components (calcium and If a magnesium mineral is contained, it is neutralized by this and an abnormal drop in pH is prevented. Therefore, in the case of dilution water that does not contain a sufficient amount of hardness component, so-called soft water, the pH becomes abnormally low without being neutralized.

Slightly acidic electrolyzed water of a certain standard is designated as a food additive sterilizer by the Ministry of Health, Labor and Welfare, but its pH range is 5 or more and 6.5 or less. Depending on the hardness of the water, there is a possibility that it may fall outside of this standard, in which case it cannot be used for food, which is inconvenient for the user.

Therefore, the problem to be solved by the present invention is to provide a technique for producing slightly acidic electrolyzed water that is highly convenient for use without causing abnormally low pH even when diluted water with low hardness is used. .

In order to solve the above problems, the present invention uses water containing minerals as water for diluting hydrochloric acid.

The effects brought about by this are as follows. That is, in the hydrochloric acid diluted with water containing minerals, almost all of the contained hardness components and salt are present as ions. When this is electrolyzed, Ca (OH) ₂ , Ba (OH) ₂ , Mg (OH) ₂ , NaOH, KOH, etc. produced at the anode are all alkali, neutralize with a part of hydrochloric acid, and have a buffering effect. To do. This prevents an abnormal drop in pH.

Therefore, the first aspect of the present invention is a method for diluting an electrolysis solution obtained by electrolyzing hydrochloric acid in a non-diaphragm electrolyzer with water to produce a slightly acidic electrolyzed water having sterilizing power. It was decided to be diluted with water containing minerals. The concentration of hydrochloric acid after dilution is highly convenient in terms of handling because the effect of minerals contained in the diluted water is sufficiently exerted, and 9% or less, which is not subject to legal regulations as a deleterious substance. On the other hand, the lower limit concentration is preferably 1.0% or more in view of electrolysis efficiency.
As mineral-containing water, any water containing minerals other than soft water, distilled water or ultrafiltered water can be used. However, when preparing slightly acidic hypochlorous acid water, which is a food additive, water suitable for drinking. Is used.

In the second aspect of the present invention, the mineral-containing water is water containing an alkali metal, an alkaline earth metal, or both. This is because alkali metals and alkaline earth metals are known as metals that generate alkali at the cathode by electrolysis, and as such metals, magnesium, calcium, barium, sodium, potassium, lithium, etc. are known, The same effect can be obtained regardless of whether they are contained alone or in a plurality of kinds.

In the third aspect of the present invention, the mineral-containing water is water containing 0.1 ppm or more and 200 ppm or less, more preferably 1 ppm or more and 100 ppm or less, or 10 ppm or more and 300 ppm or less. More preferably, it is water having a total hardness of 100 ppm or more and 300 ppm or less, or water containing the above-mentioned concentration of sodium ions and having the above hardness. Examples of such water include tap water and salt-containing mineral spring water using the groundwater of beaches and islands. Also, general tap water can be used if it has similar components.

In the fourth aspect of the present invention, the mineral-containing water is deep ocean water. Deep sea water is water from which salt and minerals in seawater collected from a certain depth of sea are removed, and contains many kinds of minerals. Of course, it also contains various alkali metals and alkaline earth metals that become alkaline components by electrolysis, and exhibits neutralizing action of hydrochloric acid generated after electrolysis.

In the method of electrolyzing hydrochloric acid or diluting the electrolyzed solution obtained by electrolyzing hydrochloric acid with water to produce a slightly acidic electrolyzed water having sterilizing power, hydrochloric acid produced by electrolysis is generated. It acts to lower the pH of the slightly acidic electrolyzed water. In that case, when the water for diluting hydrochloric acid or the water for diluting the electrolysis solution is so-called soft water having a low hardness, the pH may be abnormally low. When slightly acidic electrolyzed water is used as a food additive, it is below the pH standard set by the Ministry of Health, Labor and Welfare, which is very inconvenient, but the problem is caused by using mineral-containing water as water to dilute hydrochloric acid. Avoided. In particular, water containing an alkali metal or alkaline earth metal as a mineral component is highly effective.

First, FIG. 1 shows a method of electrolyzing the prepared diluted hydrochloric acid while sequentially diluting hydrochloric acid with water, and diluting the electrolyzed solution with water to produce slightly acidic electrolyzed water. In this method, hydrochloric acid diluted in advance with mineral-containing water is stored in the hydrochloric acid tank 3 and branched from the raw water pipe 1 by a metering pump 9 disposed on the hydrochloric acid supply pipe 4 in the hydrochloric acid diluted water pipe 2. Hydrochloric acid is quantitatively mixed with dilution water and supplied to the diaphragm membrane electrolytic cell 5. The diaphragm electrolyzer is supplied with a constant direct current from a direct current power source (not shown) to perform electrolysis. The electrolytic solution is injected and diluted into the raw water through the electrolytic solution discharge pipe 6 and discharged from the slightly acidic electrolytic water outlet 7. In this case, the hydrochloric acid stored in the hydrochloric acid tank is optimally prepared by diluting hydrochloric acid such as 35% in advance to a concentration of 1 to 9% with mineral-containing water. Dilution water has an overall hardness exceeding 100 ppm, and sodium is optimally 1 ppm or more. Groundwater, tap water, mineral spring water, deep ocean water, etc. with similar components can be used optimally. As for each flow rate ratio, with respect to the raw water 1000, the amount of branched dilution water is 0.5 to 5 and hydrochloric acid 0.1 to 1. The current value is 25 to 50 A in terms of a single tank.

By this method, an electrolysis test was performed using tap water having a hardness of 30 mg / L as raw water to confirm the effectiveness of the method. The production amount used was a slightly acidic electrolyzed water generator AP-5000 manufactured by Hokuetsu Co., Ltd. with a volume of 5000 L per hour. The raw water flow rate was 5000 L / h, the hydrochloric acid dilution water flow rate was 500 ml / h, and hydrochloric acid was diluted to 9% with deep ocean water and supplied at 240 ml / h. The electrolytic current value was 180A. As a result, slightly acidic electrolyzed water having an effective chlorine concentration of 18 ppm and a pH of 5.7 was obtained.

Next, FIG. 2 is a flow diagram of a method for preparing slightly acidic electrolyzed water by electrolyzing only hydrochloric acid diluted in advance with mineral-containing water and diluting the electrolyte with diluted water. In this method, the hydrochloric acid stored in the hydrochloric acid tank is optimally prepared by previously diluting hydrochloric acid such as 35% to a concentration of about 1 to 9% with mineral-containing water. The optimum component of the diluted water of hydrochloric acid is the same as in the previous method. As for each flow rate ratio, the amount of hydrochloric acid is 0.3 to 3 with respect to 1000 of raw water. The current value is 25 to 50 A in terms of a single tank.

By this method, an electrolysis test was performed using Apia 60 manufactured by Hokuetsu, and the effectiveness of the method was confirmed. The amount produced was 60 L per hour, the raw water flow rate was 60 L / h, and hydrochloric acid was supplied at 30 ml / h diluted to 3% with groundwater with a total hardness of 150 mg / L. When the raw water had a total hardness of 60 mg / L, slightly acidic electrolyzed water having an effective chlorine concentration of 19 ppm and a pH of 5.5 was continuously obtained, and it was confirmed that this method was effective.

FIG. 3 shows a method in which hydrochloric acid previously diluted with a mineral-containing solution is mixed and diluted to the total amount of raw water, electrolyzed, and the electrolyzed solution is used as it is as slightly acidic electrolyzed water. In this method, the hydrochloric acid stored in the hydrochloric acid tank is optimally prepared by previously diluting hydrochloric acid such as 35% to a concentration of about 1 to 9% with mineral-containing water. As for each flow rate ratio, the amount of hydrochloric acid is 0.3 to 3 with respect to 1000 of raw water. The current value is 25 to 50 A in terms of a single tank.

Flow diagram for further diluting hydrochloric acid previously diluted with mineral-containing water, diluting the electrolysis solution with raw water, and preparing slightly acidic electrolyzed water Flow diagram of preparing slightly acidic electrolyzed water by electrolyzing hydrochloric acid diluted in advance with mineral-containing water and diluting the electrolyzed solution with raw water Flow diagram of preparing slightly acidic electrolyzed water by diluting hydrochloric acid diluted with mineral-containing water in advance with the total amount of diluted water and then electrolyzing it

1. Raw water piping Hydrochloric acid diluted water branch 2. Hydrochloric acid tank 4. 4. Hydrochloric acid supply pipe Electrolytic cell 6. 6. Electrolyte discharge pipe Slightly acidic electrolyzed water outlet 8. 8. Raw water flow control valve Hydrochloric acid pump 10. Hydrochloric acid diluted water flow control valve

Claims (2)

In a method of diluting an electrolysis solution obtained by electrolyzing hydrochloric acid in a non-diaphragm electrolyzer with water to produce a slightly acidic electrolyzed water having bactericidal power, hydrochloric acid was diluted with mineral-containing water and prepared. Method for producing slightly acidic electrolyzed water The mineral-containing water is deep ocean water, and has a total hardness of 0.1 ppm or more and 200 ppm or less, more preferably 1 ppm or more and 50 ppm or less, or 10 ppm or more and 300 ppm or less, more preferably 50 ppm or more and 300 ppm or less. Of slightly acidic electrolyzed water characterized by