JPH09122651A - Weakly acidic electrolytic acidic water for sterilization and disinfection of hemodialyzer and its supplying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electrolytic acidic water which decreases damage of an instrument and has little influence to environment used in the case where the inside of a pipeline for a dialyzate is sterilized by electrolyzing an electrolytic additive contg. a small amt. of sodium chloride and chloric acid in an electrolytic tank with platinum electrodes and diluting hypochlorous acid and chloric acid generated with water. SOLUTION: When a weakly acidic electrolytic acidic water is formed, an electrolytic tank 30 and a mixing tank 40 are arranged and in the electrolytic tank 30, both an anode 31 and a cathode 32 are constituted of plutinum and a membrane is excluded to react the components generated on both electrodes 31 and 32. The alkali component generated is neutralized thereby with chloric acid and it is chemically excluded. In addition, hypochlorous acid and chloric acid generated in the electrolytic tank 30 are transferred into a mixing tank 40, wherein they are diluted with water to take out it as a weakly acidic electrolytic acidic water. By utilizing the weakly acidic electrolytic acidic water like this, medical instruments, especially a hemodialysis apparatus can be sterilized and disinfected in a short time and damage of the instrument and influence to environment for waste water treatment can be decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electrolyzed acidic water used for medical equipment, particularly hemodialysis equipment, for sterilizing and disinfecting the inside of a dialysate pipe, and a supply device thereof.

[0002]

2. Description of the Related Art Hypochlorous acid is well known as a substance having a bleaching and bactericidal action. Therefore, conventionally, sodium chlorite (NaOCl), which is a salt of hypochlorous acid, has been used for sterilization and disinfection in the dialysate pipe of a hemodialysis machine. However, since this sodium hypochlorite is liable to react and dangerous, it is necessary for hospital staff who handle sodium hypochlorite to be careful, and it is known that the above-mentioned equipment has high metal corrosiveness. . Further, since the chlorine concentration in the waste liquid after sterilization is high, there is a problem that it has an adverse effect on the sewage purification tank.

On the other hand, in recent years, water having a certain activity is expressed as active water, and water having a specific function is particularly distinguished as functional water. The method of activating water is generally a method using electromagnetic energy, and the activation treatment includes various methods such as an electrolysis method and a high voltage treatment. Also, there is an increasing tendency to make ordinary tap water more functional, and in particular 0.0% to promote electrolysis.
Theoretical explanation has been made that 5% of salt is added and electrolyzed through a diaphragm, and acidic water obtained from the anode side functions as sterilizing water.

As described above, the anode side electrolyzed through the diaphragm contains chlorine and oxygen, and has a hydrogen ion concentration (pH) of 2.
Water obtained as a solution of 7 or less has a redox potential (ORP: o
xidation reduction potential) With a potential of 1,100 mV or more, the potential is far higher than 900 mV, which is considered to be the limit of the living sphere of microorganisms, and a situation in which an oxidation reaction is likely to occur is created, and the action of chlorine-containing compounds causes a fast-acting effect. Shows strong bactericidal activity. To be precise, this functional water is called “strongly acidic electrolysis-produced aqueous solution”, but it is generally referred to as “electrolyzed acidic water”, “electrolytically oxidized water”, etc. It is referred to as "electrolytic acidic water". Then, as described above, the strongly acidic electrolyzed acidic water has recently come to be used as a substitute for the sodium hypochlorite for sterilization of medical equipment such as a hemodialysis machine.

Here, a method of producing the strongly acidic electrolyzed acidic water and its principle will be described with reference to the drawings. FIG. 13 shows a schematic structure of an apparatus for generating strongly acidic electrolyzed acidic water, which is composed of a mixing tank 20 and an electrolytic tank 10. Then, in the electrolytic cell 10, platinum (Pt) is used as an electrode material for the anode 2 and the cathode 3, and the acidic component produced at the anode 2 and the alkaline component produced at the cathode 3 are physically mixed so as not to mix with each other. In order to exclude it, the diaphragm 1 is provided at the center of the electrolytic cell 10. In such a structure, first, water and sodium chloride (NaCl) as an electrolysis additive are introduced into the mixing tank 20 and mixed, and the mixed saline solution is mixed in the electrolytic tank 10.
And is electrolyzed by applying a voltage between the anode 2 and the cathode 3.

The reaction occurring at the anode 2 and the cathode 3 at this time will be described with reference to FIGS. 8, 9 and 10. FIG. 8 is a diagram showing the reaction taking place at the anode 2 step by step. First, chlorine ion (Cl ⁻ ) and hydroxide ion (OH
^-) respectively electrons anode (e ^-) to release each chlorine radical (· Cl) and hydroxyl radicals (· OH)
become. Each reaction is represented by the following chemical formulas 1 and 2.

[Chemical 1] Cl ⁻ → · Cl + e ⁻

[Chemical Formula 2] OH ⁻ → · OH + e ⁻

The chlorine radical (.Cl) and the hydroxyl radical (.OH) are combined to generate hypochlorous acid (HOCl). The reaction at this time is represented by Chemical Formula 3.

[Chemical Formula 3] -Cl + -OH-> HOCl Therefore, the above Chemical Formulas 1 to 3 can be summarized as the following Chemical Formula 4.

Embedded image Cl ⁻ + OH ⁻ → HOCl + 2e ⁻

[0008] Next, FIG. 9 is the same, a diagram showing stepwise the secondary reactions at the anode 2, adsorbed chloride ions to the anode 2 (Cl ^-) is chlorine emit electrons to anode Gas (C
l ₂ ), which can be expressed as

Embedded image 2Cl ⁻ → Cl ₂ + 2e ⁻ And chlorine gas (Cl ₂ ) rapidly reacts with water molecules (H ₂ O), and as shown in the following chemical formula 6, hypochlorous acid (HOCl) ) And chloric acid (HCl).

Embedded image Cl ₂ + H ₂ O → HOCl + HCl The above chemical formulas 5 and 6 can be summarized as the following chemical formula 7.

Embedded image 2Cl ⁻ + H ₂ O → HOCl + HCl + 2e ⁻

[0009] That is, from the formula 4 and formula 7, the chlorine ions can emit, undergoing an oxidation reaction comprising a hypochlorite (HOCl) and chlorate (HCl) (Cl ^{- -)} electrons (e) I understand. Also, since chlorine gas (Cl ₂ ) is generated, the device needs to be degassed to discharge this gas.

On the contrary, at the cathode 3, as shown in FIG. 10, first, sodium ions (Na ⁺ ) are adsorbed on the cathode 3 to generate electrons (e
^- ) And becomes sodium metal (Na). This reaction is represented by Chemical formula 8.

[Image Omitted] Na ⁺ + e ⁻ → Na Sodium metal (Na) thus produced rapidly reacts violently with water molecules (H ₂ O) to produce hydrogen gas (H ₂ ) and Becomes sodium hydroxide (NaOH).

Embedded image 2Na + 2H ₂ O → H ₂ + 2NaOH

At this time, sodium hydroxide (NaOH) is
Chemical formula 9 is represented as chemical formula 10 because it is ionized in an aqueous solution.

Embedded image 2Na + 2H ₂ O → H ₂ + 2Na ⁺ + 2OH ^{− The} above Chemical Formulas 8 and 10 are summarized as Chemical Formula 11 below.

Embedded image 2H ₂ O + 2e ⁻ → H ₂ + 2OH ^{− From} this result, it is as if the water molecule (H ₂ O) was a direct electron (e ⁻ ).
To receive hydrogen gas (H ₂ ) and hydroxide ions (O
H ^-) and the reducing reaction can be seen of it is seen as happening is. The alkaline water obtained from the cathode 3 functions similarly to soapy water.

[0012]

The bactericidal effect of the strongly acidic electrolyzed acidic water produced on the anode 2 side of the apparatus shown in FIG. 13 can be killed by general bacteria within a short time of 15 to 30 seconds. It is clear that there is. However, the most important thing to note when using this strongly acidic electrolyzed acidic water in daily clinical practice is that its bactericidal effect is rapidly lost due to the presence of organic substances such as blood. Here, one example is shown. For example, at a temperature of 24 ° C, pH
2.4, ORP 1125 mV, 200 ml of strongly acidic electrolyzed water with residual chlorine 25 ppm, human serum (total protein 5.
48 g / dl, albumin 57.2%) was added to 50 μl of human serum alone under the same conditions as above.
How the above pH, ORP, viable cell count and residual chlorine change with time to 0 μl will be described with reference to FIGS. 11 and 12.

Under each of the above conditions, first, MRSA
(Methicillin Resistant Staphylococcus Aureus) bacterial solution was added at 5 × 10 ⁵ CFU / ml, and the residual chlorine was hypochlorite ion (OCl ⁻ ), hypochlorous acid (HOC).
l), chlorine gas (Cl ₂ ) and other chlorine compounds are included. Then, FIG. 11 and FIG. 12 are graphs showing changes with time when 200 μl of human serum was added under the above conditions.

First, when 50 μl of the above-mentioned human serum was added, the pH was adjusted to pH 2.4 and ORP 11 after 15 seconds.
Although it was almost unchanged at 13 mV, the residual chlorine was 1
A drastic decrease of 0 ppm was observed, and the results were observed over time. As a result, the pH did not change to 2.4 even after 2 minutes. And the ORP was slightly lowered to 1104 mV, the residual chlorine remained at a low value of 10 ppm, and
The initially added MRSA was completely killed within 15 seconds.

However, when the human serum alone was increased to 200 μl under the same conditions as above, as shown in FIGS. 11 and 12, the pH shown in the graph a showed no change over time. However, O shown in graph b
RP slowly decreases with time and becomes 108 after 15 seconds.
It becomes 3 mV. The residual chlorine shown in the graph c also became 2 ppm after 15 seconds, and the viable cell count shown in the graph d was 5 × 10 ³ CFU / ml. After that, the decrease in the number of bacteria was slow, and even after 2 minutes, 4 × 10 ² CFU /
A viable cell count of ml was observed.

From these experimental results, the pH does not serve as an index of the bactericidal effect, and the oxidation-reduction potential almost correlates with residual chlorine. Therefore, although it can serve as an index to some extent, the essence of the bactericidal effect is hypochlorite. It can be seen that the amount of acid is strongly affected. And strong acidic electrolyzed acidic water 200 ml
Even if a very small amount of serum is added, the bactericidal effect is drastically reduced, and the limit is 0.
It has been confirmed that the organic matter has a concentration of 1%.

Chloride ions contained in the strongly acidic electrolyzed acidic water do not deactivate because they have no activity.
Also, it is not deactivated by exposure to oxygen in the air. That is, there is a large amount of oxygen in the electrolyzed acidic water, and there is a high possibility that oxygen will be released from the liquid into the air. Then, hypochlorous acid, which is the main component of the bactericidal effect, is easily reduced by ultraviolet rays and decomposes to lower the redox potential. Because of this unstable chemical substance, when storing strong acidic electrolyzed acidic water at room temperature, it is a principle to store it in a light-tight sealed container. The limit is 60 days, and only a sealed container can be opened within 15 days. In the case of a container, it is considered that it is desirable to use 32 hours as a guide, and it is necessary to use fresh one as soon as possible after production.

Since strongly acidic electrolyzed acidic water produces chlorine gas as described above, it is necessary to take measures to safely disperse the gas at the production site and storage tank. Particularly, in the air above the storage tank, about 10
It should be used in mind that there is chlorine gas close to 0 ppm, and chlorine gas concentration of about 10 ppm is detected even near the bottom of the hand washing sink used in the spraying method.
In addition, it has a strong corrosive effect on metals and may destroy building facilities, so careful consideration must be given to disposal. When discarding a large amount, it is necessary to take measures such as mixing and discarding alkaline water produced at the same time in the production process or adding ascorbic acid to suppress the generation of chlorine gas before discarding.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to sterilize and disinfect medical equipment, in particular, hemodialysis equipment in a short time, which is safe for patients and staff. The present invention is to provide electrolytic acid water and a supply device therefor, which are less likely to be damaged and which have less impact on the wastewater treatment environment.

[0020]

The present invention relates to electrolytic acid water for sterilization and disinfection, and the above object of the present invention is to electrolyze an electrolytic additive solution containing a small amount of salt and chloric acid in an electrolytic cell whose electrodes are platinum. , By diluting the produced hypochlorous acid and chloric acid with water. Further, the electrolytic acidic water generator of the present invention, an electrolytic additive solution tank for storing an electrolytic additive solution containing salt and chloric acid, and an electrolytic tank for electrolyzing the electrolytic additive solution sent from the electrolytic additive solution tank. , A mixing tank for diluting water with hypochlorous acid and chloric acid obtained in the electrolytic cell, and a pH meter for checking produced water, a storage tank and a supply pump. .

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, water for sterilizing and disinfecting medical equipment, particularly hemodialysis equipment, has a pH of 5.0 to 5.5 with respect to the above electrolyzed acidic water exhibiting strong acidity.
Residual chlorine concentration 20 ppm or more, ORP 800-1,0
It is a weakly acidic electrolyzed acidic water exhibiting 50 mV. This is shown in Figure 7.
As is clear from the graph of the abundance ratio of free available chlorine with respect to each pH, a pH of 5 with the highest abundance ratio of hypochlorous acid was generated by electrolysis, and sodium hypochlorite was diluted to 200 ppm. It is devised so that the same or more bactericidal effect as in the case of the above can be obtained and residual chlorine can be effectively used.

The method for producing weakly acidic electrolyzed acidic water of the present invention will be described with reference to FIG. FIG. 1 is a schematic view of an apparatus for producing weakly acidic electrolyzed acidic water, which includes an electrolyzer 30 and a mixing tank 4
0. Further, in the electrolytic cell 30, the electrodes are made of platinum (Pt) for both the anode 31 and the cathode 32, similarly to the above-described conventional apparatus for producing strongly acidic electrolyzed acidic water.
Then, in the conventional strongly acidic water generator, a diaphragm is provided at the center of the electrolytic cell so that the acidic component produced at the anode and the alkaline component produced at the cathode do not mix,
The weakly acidic electrolyzed acidic water producing electrolytic cell of the present invention is not provided with a diaphragm in order to react the components generated at the anode 31 and the cathode 32. In other words, in weakly acidic electrolyzed water, an alkaline component (NaOH) is neutralized with chloric acid (HCl) to be chemically eliminated.

Here, the principle of producing the weakly acidic electrolyzed acidic water shows a reaction similar to the electrolysis of the strongly acidic electrolyzed acidic water as shown in FIGS. 8, 9 and 10. In other words, when water (H ₂ O) containing a small amount of salt (NaCl) and chloric acid (HCl) is electrolyzed as an electrolytic additive, the anode 3 of the electrolytic cell 30 is electrolyzed.
On the 1st side, first, as shown in the above chemical formula 1, the chlorine ion (Cl ⁻ ) is deprived of an electron by the electrode and becomes a highly reactive chlorine radical (· Cl). And this chlorine radical (・
Cl) reacts with each other to form chlorine gas (Cl ₂ ) as shown in Chemical formula 5 above. Further, this chlorine gas (Cl ₂ ) reacts with water (H ₂ O) as shown in the above chemical formula 6 to cause hypochlorous acid.
(HOCl) and chloric acid (HCl) are produced.

On the other hand, on the cathode 32 side of the electrolytic cell 30,
As shown in the above chemical formula 8, sodium ion (Na ⁺ ) receives an electron at the electrode and becomes highly reactive metallic sodium (Na). Then, this metallic sodium reacts with water (H ₂ O) to become hydrogen gas (H ₂ ) and sodium hydroxide (NaOH) as shown in Chemical formula 9 above. However, in this apparatus for generating weakly acidic electrolyzed acidic water, since there is no diaphragm provided in the apparatus for generating strongly acidic electrolyzed acidic water as described above, the chloric acid (HCl) generated on the anode 31 side is Sodium hydroxide (NaOH) generated on the cathode 32 side undergoes a neutralization reaction,
(H ₂ O) and common salt (NaCl). Then, the electrolytic bath 30
The hypochlorous acid (HOCl) and the chloric acid (HCl) produced in step 1 are sent to the mixing tank 40 where they are diluted with water and taken out as weakly acidic electrolyzed acidic water.

[0025]

EXAMPLES Next, a weak acidic electrolyzed acidic water producing and supplying apparatus according to the present invention will be described in detail with reference to specific examples. FIG.
(A) is a front view of a supply device for generating weakly acidic electrolyzed acidic water,
(B) and (C) are side views, and (D) are plan views. This production and supply device is composed of a pump motor / valve control unit 4, an electric unit 5, an electrolysis unit 6, a storage tank 7 and a weakly acidic water supply pump 8, and an electrolysis additive liquid tank 9 is separately arranged. . FIG. 3 is a diagram showing a series of flows of water and produced water in the above apparatus, corresponding to FIG. 2. First, the electrolysis additive liquid tank 9 is sent via the pump motor / valve control unit 4 and the electric unit 5. The generated salt and chloric acid are electrolyzed together with the RO water in the electrolysis unit 6, and the generated hypochlorous acid and chloric acid are sent to the storage tank 7. The generated water stored in the storage tank 7 is sent via the supply pump 8 to the multi-person hemodialysis system 12 connected to the generator via the motor valve 11A. The produced water sent to the multi-user hemodialysis system sterilizes the system and the piping and bedside monitor located further ahead. The electric unit 5 is for controlling the series of flows described above.

The overall size of the device is 900 (W) ×
It is 450 (D) x 1,165 (H) and the operating weight is 160
Kg, power supply AC100V × 800W, 50 / 60Hz
Use Further, the production capacity is 1000 liters / hr, the supply pump 8 is a magnet type, and the capacity of each tank is 100 liters of the produced water tank and 20 liters of the electrolytic additive solution tank. The raw water is RO
Water (1.5-2.5 Kgf / cm ² ) is used. By using this generator, pH of 5.0-
5.5, residual chlorine concentration 50-80 ppm and ORP 8
The product water of 00-1000 mV was obtained.

Here, the weakly acidic electrolyzed acidic water obtained as described above is compared with the strongly acidic electrolyzed acidic water. First, FIG. 4 and FIG. 5 are compared with each other by showing the effect of organic substances on the bactericidal activity of strongly acidic electrolyzed acidic water and weakly acidic electrolyzed acidic water. In FIG. 4, 200 ml of strongly acidic electrolyzed acidic water was used at a temperature of 24.
Serum was 100 μm under conditions of 6 ° C., pH 2.39, ORP 1122 mV, and residual chlorine concentration of 25 ppm.
l, 200 μl, 500 μl and 1000 μl,
Viable cell count of each bacterium after a certain period of time (unit: CFU / ml)
Is shown. On the other hand, FIG. 5 shows 200 m of weakly acidic electrolyzed acidic water.
1 at a temperature of 24.6 ° C., pH 5.55, ORP 890
Under the conditions of mV and residual chlorine concentration of 80 ppm, 1000 μl, 2000 μl and 5000 μl of serum were added, and the viable cell count of each bacterium after a certain period of time (unit: CFU / m
1) is shown.

Also in the deactivation test with organic matter, the bactericidal effect disappeared at a concentration of 0.1% or more in the above strongly acidic electrolyzed acidic water, as is clear from FIGS. 4 and 5. In addition, weakly acidic electrolyzed acidic water is about 10 times 1%
Even the organic substances in are not deactivated. That is, it is clear that the organic matter is not easily inactivated. In addition, the amount of residual chlorine is large even in the deactivation test by storage at room temperature, and the effect is long-lasting and stable. In particular, the concentration of chlorine gas generated in the gas stored in the upper part of the storage container is about 100 ppm in the case of strongly acidic electrolyzed acidic water, whereas it is about 1 ppm in weakly acidic electrolyzed acidic water. It can be seen that chlorine is less likely to volatilize.

The metal corrosive action is also less corrosive than the strongly acidic electrolytic acidic water. That is, in the case of weak acidity, the corrosion potential is about 470 mV to 600 mV, and about 800 for the sodium hypochlorite (concentration 200 ppm).
It becomes mV, and the former has a lower corrosion potential. Therefore, for example, corrosion resistant stainless steel (SUS-316) will not corrode at normal operating temperatures. In these metal corrosivity experiments, it was found that the corrosive action became weaker in the order of sodium hypochlorite, strongly acidic electrolyzed acidic water, and weakly acidic electrolyzed acidic water. FIG. 6 shows a comparison result of the strongly acidic electrolyzed acidic water and the weakly acidic electrolyzed acidic water.

[0030]

EFFECTS OF THE INVENTION When the above weakly acidic electrolyzed acidic water is used for sterilizing and disinfecting a hemodialyzer for a single person and for a large number of people, it causes the disappearance of viable bacteria within 5 minutes, and with conventional sodium hypochlorite. It takes 60 minutes, but 20 minutes of sterilization can sufficiently achieve the purpose. In addition, in the washing time required until the residual chlorine concentration becomes 0, it took 50 minutes to perform post-washing with conventional sodium hypochlorite, but with post-washing using weakly acidic electrolytic acidic water. It is possible to greatly shorten the. And the sterilization ability was almost the same as the conventional 500-600 ppm sodium hypochlorite (pH 8.5-9.0). Further, even with respect to the effect on the wastewater septic tank, the chlorine concentration of the waste liquid in the disinfection process is low when the above-mentioned weak acidic electrolyzed acidic water is used, and the safety is higher due to the components of the electrolytically added liquid and the produced water, and their residual properties. It is a thing.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus for producing and supplying weakly acidic electrolyzed acidic water of the present invention.

FIG. 2 is a diagram showing an example of a weakly acidic electrolyzed acidic water generator, (A) is a front view, (B) is a left side view, (C) is a right side view, and (D) is a plan view. .

FIG. 3 is a diagram showing a series of flows of water and produced water in an apparatus for producing weakly acidic electrolyzed acidic water.

FIG. 4 is a diagram showing the influence of organic substances on the bactericidal activity of strongly acidic electrolyzed acidic water.

FIG. 5 is a diagram showing the influence of organic substances on the bactericidal activity of weakly acidic electrolyzed acidic water.

FIG. 6 is a diagram showing a comparison result of strongly acidic electrolyzed acidic water and weakly acidic electrolyzed acidic water.

FIG. 7 is a graph showing a graph of the abundance ratio of free available chlorine with respect to pH.

FIG. 8 is a schematic diagram showing stepwise a reaction occurring at the anode.

FIG. 9 is a schematic diagram showing stepwise secondary reactions at the anode.

FIG. 10 is a schematic view showing the reaction taking place at the cathode stepwise.

FIG. 11 is a view showing a strong acid electrolyzed acidic water sterilizing effect on serum.

FIG. 12 is a view showing the effect of sterilizing strongly acidic electrolyzed acidic water on serum.

FIG. 13 is a schematic view of a conventional device for producing strongly acidic electrolyzed acidic water.

[Explanation of symbols]

1 Diaphragm 2, 31 Anode 3, 32 Cathode 4 Pump Motor / Valve Control Unit 5 Electric Unit 6 Electrolysis Unit 7 Storage Tank 8 Weak Acidic Water Supply Pump 9 Electrolysis Additive Tank 10, 30 Electrolysis Tank 11 Motor Valve 12 Single Or Multi-user hemodialysis system 20, 40 mixing tank

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 7, 1995

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

Title: Hemodialysis device Weakly acidic electrolyzed acidic water for sterilization and its supply device

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electrolyzed acidic water used for medical equipment, particularly hemodialysis equipment, for sterilizing and disinfecting the inside of a dialysate pipe, and a supply device thereof.

[0002]

2. Description of the Related Art Hypochlorous acid is well known as a substance having a bleaching and bactericidal action. Therefore, conventionally, sodium hypochlorite (NaOCl), which is a salt of hypochlorous acid, has been used for sterilization and disinfection in the dialysate pipe of a hemodialysis apparatus. However, since this sodium hypochlorite is liable to react and dangerous, it is necessary for hospital staff who handle sodium hypochlorite to be careful, and it is known that the above-mentioned equipment has high metal corrosiveness. . Further, since the chlorine concentration in the waste liquid after sterilization is high, there is a problem that it has an adverse effect on the sewage purification tank.

On the other hand, in recent years, water having a certain activity is expressed as active water, and water having a specific function is particularly distinguished as functional water. The method of activating water is generally a method using electromagnetic energy, and the activation treatment includes various methods such as an electrolysis method and a high voltage treatment. Also, there is an increasing tendency to make ordinary tap water more functional, and in particular 0.0% to promote electrolysis.
Theoretical explanation has been made that 5% of salt is added and electrolyzed through a diaphragm, and acidic water obtained from the anode side functions as sterilizing water.

As described above, the anode side electrolyzed through the diaphragm contains chlorine and oxygen, and has a hydrogen ion concentration (pH) of 2.
Water obtained as a solution of 7 or less has a redox potential (OR
P: oxidation reduction pot
above 100 mV, the potential is far higher than 900 mV, which is considered to be the limit of the living sphere of microorganisms, and the oxidative reaction is likely to occur. Show power. To be precise, this functional water is called "strongly acidic electrolysis-produced aqueous solution", but it is generally treated as "electrolytic acid water", "electrolytic oxidation water", etc.,
In the present specification, it is referred to as "electrolytic acidic water". Then, as described above, the strongly acidic electrolyzed acidic water has recently come to be used as a substitute for the sodium hypochlorite for sterilization of medical equipment such as a hemodialysis machine.

Here, a method of producing the strongly acidic electrolyzed acidic water and its principle will be described with reference to the drawings. FIG. 13 shows a schematic structure of an apparatus for generating strongly acidic electrolyzed acidic water, which is composed of a mixing tank 20 and an electrolytic tank 10. In the electrolytic cell 10, platinum (Pt) is used as an electrode material for the anode 2 and the cathode 3, and the acidic component produced at the anode 2 and the alkaline component produced at the cathode 3 are physically mixed so as not to mix with each other. In order to exclude it, the diaphragm 1 is provided at the center of the electrolytic cell 10. In such a configuration, first, water and salt (Na
Cl) is introduced and mixed, and the mixed saline is sent to the electrolytic bath 10 and electrolyzed by applying a voltage between the anode 2 and the cathode 3.

The reaction occurring at the anode 2 and the cathode 3 at this time will be described with reference to FIGS. 8, 9 and 10. FIG. 8 is a diagram showing the reaction taking place at the anode 2 step by step. First, chlorine ions (Cl ⁻ ) and hydroxide ions (OH ⁻ ) respectively emit electrons (e ⁻ ) to the anode, respectively. It becomes chlorine radical (.Cl) and hydroxyl radical (.OH). Each reaction is represented by the following chemical formulas 1 and 2.

Embedded image

Embedded image

The chlorine radical (.Cl) and the hydroxyl radical (.OH) are combined to form hypochlorous acid (HO).
Cl) is produced. The reaction at this time is represented by Chemical Formula 3.

Embedded image Therefore, the above Chemical Formulas 1 to 3 can be summarized as Chemical Formula 4 below.

Embedded image

Next, FIG. 9 is a diagram showing the secondary reaction at the anode 2 stepwise as in the above. Chlorine ions (Cl ⁻ ) adsorbed on the anode 2 release electrons to the anode to cause chlorine. Gas (C
l ₂ ), which can be expressed as Chemical formula 5.

Embedded image Then, chlorine gas (Cl ₂ ) promptly becomes a water molecule (H
₂ O) to produce hypochlorous acid (HOCl) and hydrochloric acid (HCl) as shown in the following chemical formula 6.

[Chemical 6] The above chemical formulas 5 and 6 are summarized as the following chemical formula 7.

Embedded image

That is, from the above chemical formulas 4 and 7, chlorine ions (Cl ⁻ ) release electrons (e ⁻ ) and hypochlorite (HO ⁻ )
It can be seen that an oxidation reaction of Cl) and hydrochloric acid (HCl) has occurred. Further, since chlorine gas (Cl ₂ ) is generated, the apparatus needs to be degassed to discharge this gas.

On the contrary, at the cathode 3, as shown in FIG. 10, first, sodium ions (Na ⁺ ) are adsorbed on the cathode 3 to receive electrons (e ⁻ ) and become sodium metal (Na).
This reaction is represented by Chemical formula 8.

Embedded image The sodium metal (Na) thus produced rapidly reacts violently with water molecules (H ₂ O) as shown in Chemical formula 9 to produce hydrogen gas (H ₂ ) and sodium hydroxide (NaO).
H)

Embedded image

At this time, sodium hydroxide (NaO
Since H) is ionized in an aqueous solution, Chemical formula 9 is represented as Chemical formula 10.

Embedded image The above chemical formulas 8 and 10 are summarized as the following chemical formula 11.

Embedded image From this result, it seems as if the water molecule (H ₂ O) directly receives the electron (e ⁻ ) and becomes hydrogen gas (H ₂ ) and hydroxide ion (OH ⁻ ) to cause the reduction reaction. I understand. The alkaline water obtained from the cathode 3 functions similarly to soapy water.

[0012]

The bactericidal effect of the strongly acidic electrolyzed acidic water produced on the anode 2 side of the apparatus shown in FIG. 13 can be killed by general bacteria within a short time of 15 to 30 seconds. It is clear that there is. However, the most important thing to note when using this strongly acidic electrolyzed acidic water in daily clinical practice is that its bactericidal effect is rapidly lost due to the presence of organic substances such as blood. Here, one example is shown. For example, at a temperature of 24 ° C, pH
2.4, ORP 1125 mV, 200 ml of strongly acidic electrolyzed water with residual chlorine 25 ppm, human serum (total protein 5.
48 g / dl, albumin 57.2%) was added to 50 μl of human serum alone under the same conditions as above.
How the above pH, ORP, viable cell count and residual chlorine change with time to 0 μl will be described with reference to FIGS. 11 and 12.

Under each of the above conditions, first, MRSA
(Methicillin Resistant St
aphylococcus Aureus) 5 ×
10 ⁵ CFU / ml was added, and the residual chlorine was hypochlorite ion (OCl ⁻ ) or hypochlorous acid (HO).
Cl), chlorine gas (Cl ₂ ) and other chlorine compounds are all included. Then, FIG. 11 and FIG. 12 are graphs showing changes with time when 200 μl of human serum was added under the above conditions.

First, when 50 μl of the above-mentioned human serum was added, the pH was adjusted to pH 2.4 and ORP 11 after 15 seconds.
Although it was almost unchanged at 13 mV, the residual chlorine was 1
A drastic decrease of 0 ppm was observed, and the results were observed over time. As a result, the pH did not change to 2.4 even after 2 minutes. And the ORP was slightly lowered to 1104 mV, the residual chlorine remained at a low value of 10 ppm, and
The initially added MRSA was completely killed within 15 seconds.

However, when the human serum alone was increased to 200 μl under the same conditions as above, as shown in FIGS. 11 and 12, the pH shown in the graph a showed no change over time. However, O shown in graph b
RP slowly decreases with time and becomes 108 after 15 seconds.
It becomes 3 mV. The residual chlorine shown in the graph c also became 2 ppm after 15 seconds, and the viable cell count shown in the graph d was 5 × 10 ³ CFU / ml. After that, the decrease in the number of bacteria was slow, and even after 2 minutes, 4 × 10 ² CFU /
A viable cell count of ml was observed.

From these experimental results, the pH does not serve as an index of the bactericidal effect, and the oxidation-reduction potential almost correlates with residual chlorine. Therefore, although it can serve as an index to some extent, the essence of the bactericidal effect is hypochlorite. It can be seen that the amount of acid is strongly affected. And strong acidic electrolyzed acidic water 200 ml
Even if a very small amount of serum is added, the bactericidal effect is drastically reduced, and the limit is 0.
It has been confirmed that the organic matter has a concentration of 1%.

Chloride ions contained in the strongly acidic electrolyzed acidic water do not deactivate because they have no activity.
Also, it is not deactivated by exposure to oxygen in the air. That is, there is a large amount of oxygen in the electrolyzed acidic water, and there is a high possibility that oxygen will be released from the liquid into the air. Then, hypochlorous acid, which is the main component of the bactericidal effect, is easily reduced by ultraviolet rays and decomposes to lower the redox potential. Because of this unstable chemical substance, when storing strong acidic electrolyzed acidic water at room temperature, it is a principle to store it in a light-tight sealed container. The limit is 60 days, and only a sealed container can be opened within 15 days. In the case of a container, it is considered that it is desirable to use 32 hours as a guide, and it is necessary to use fresh one as soon as possible after production.

Since strongly acidic electrolyzed acidic water produces chlorine gas as described above, it is necessary to take measures to safely disperse the gas at the production site and storage tank. Particularly, in the air above the storage tank, about 10
It should be used in mind that there is chlorine gas close to 0 ppm, and chlorine gas concentration of about 10 ppm is detected even near the bottom of the hand washing sink used in the spraying method.
In addition, it has a strong corrosive effect on metals and may destroy building facilities, so careful consideration must be given to disposal. When discarding a large amount, it is necessary to take measures such as mixing and discarding alkaline water produced at the same time in the production process or adding ascorbic acid to suppress the generation of chlorine gas before discarding.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to sterilize and disinfect medical equipment, in particular, hemodialysis equipment in a short time, which is safe for patients and staff. The present invention is to provide electrolytic acid water and a supply device therefor, which are less likely to be damaged and which have less impact on the wastewater treatment environment.

[0020]

The present invention SUMMARY OF] relates sterilizing electrolytic acid water, the object of the present invention, the electrolyte additive solution containing a small amount of sodium chloride and hydrochloric acid, electrolytic reactor with by electrolysis, were generated following This is accomplished by diluting chlorous acid and hydrochloric acid with water. Further, the electrolytic water generator of the present invention is
An electrolytic additive solution tank for storing an electrolytic additive solution containing hydrochloric acid , an electrolytic bath for electrolyzing the electrolytic additive solution sent from the electrolytic additive solution tank, and hypochlorous acid and hydrochloric acid obtained in the electrolytic bath. It is achieved by comprising a mixing tank for mixing and diluting with water, and a pH meter for checking produced water, a storage tank and a supply pump.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, water for sterilizing and disinfecting medical equipment, particularly hemodialysis equipment, has a pH of 5.0 to 5.5 with respect to the above electrolyzed acidic water exhibiting strong acidity.
Residual chlorine concentration 20 ppm or more, ORP 800-1,0
It is a weakly acidic electrolyzed acidic water exhibiting 50 mV. This is shown in Figure 7.
As is clear from the graph of the abundance ratio of free available chlorine with respect to each pH, a pH of 5 with the highest abundance ratio of hypochlorous acid was generated by electrolysis, and sodium hypochlorite was diluted to 200 ppm. It is devised so that the same or more bactericidal effect as in the case of the above can be obtained and residual chlorine can be effectively used.

The method for producing weakly acidic electrolyzed acidic water of the present invention will be described with reference to FIG. FIG. 1 is a schematic view of an apparatus for producing weakly acidic electrolyzed acidic water, which includes an electrolyzer 30 and a mixing tank 4
0. In addition, in the electrolytic cell 30, both the anode 31 and the cathode 32 are made of platinum (Pt) as electrodes, as in the above-described conventional apparatus for producing strongly acidic electrolyzed acidic water. In the conventional strongly acidic water generator, a diaphragm is provided at the center of the electrolytic cell so that the acidic component produced at the anode and the alkaline component produced at the cathode are not mixed, but the weakness of the present invention is weak. Acid electrolysis In the electrolysis tank for producing acidic water, the anode 3
No diaphragm is provided to react the components generated at 1 and the cathode 32. That is, in weakly acidic electrolyzed water, the alkaline component (NaOH) is neutralized with hydrochloric acid (HCl) to be chemically eliminated.

Here, the principle of producing the weakly acidic electrolyzed acidic water shows a reaction similar to the electrolysis of the strongly acidic electrolyzed acidic water as shown in FIGS. 8, 9 and 10. In other words, salt (NaCl) and hydrochloric acid (HC
When water (H ₂ O) containing a small amount of 1) is electrolyzed, chlorine ions (Cl ⁻ ) are first deprived of electrons at the electrodes on the anode 31 side of the electrolytic cell 30, as shown in Chemical Formula 1 above. It becomes highly reactive chlorine radical (.Cl). Then, the chlorine radicals (.Cl) react with each other to become chlorine gas (Cl ₂ ) as shown in Chemical formula 5 above. Further, this chlorine gas (Cl ₂ ) is converted into water (H ₂
O) to react with hypochlorous acid (HOCl) and hydrochloric acid (HC
l) is generated.

On the other hand, on the cathode 32 side of the electrolytic cell 30,
Sodium ion (Na ⁺ ) as represented by the above chemical formula 8
Receives electrons at the electrode and has high reactivity with metallic sodium (N
a). Then, this metallic sodium reacts with water (H ₂ O) to express hydrogen gas (H
₂ ) and sodium hydroxide (NaOH). However, in this apparatus for generating weakly acidic electrolyzed acidic water, since there is no diaphragm provided in the apparatus for generating strongly acidic electrolyzed acidic water as described above, the hydrochloric acid (HC
l) and sodium hydroxide (NaOH) generated on the cathode 32 side undergo a neutralization reaction to become water (H ₂ O) and salt (NaCl). Then, the hypochlorous acid (HOCl) and hydrochloric acid (HCl) produced in the electrolytic bath 30 are sent to the mixing bath 40 where they are diluted with water and taken out as weakly acidic electrolyzed acidic water.

[0025]

EXAMPLES Next, a weak acidic electrolyzed acidic water producing and supplying apparatus according to the present invention will be described in detail with reference to specific examples. FIG.
(A) is a front view of a supply device for generating weakly acidic electrolyzed acidic water,
(B) and (C) are side views, and (D) are plan views. This production and supply device is composed of a pump motor / valve control unit 4, an electric unit 5, an electrolysis unit 6, a storage tank 7 and a weakly acidic water supply pump 8, and an electrolysis additive liquid tank 9 is separately arranged. . FIG. 3 is a diagram showing a series of flows of water and produced water in the above apparatus, corresponding to FIG. 2. First, the electrolysis additive liquid tank 9 is sent via the pump motor / valve control unit 4 and the electric unit 5. The generated salt and hydrochloric acid are electrolyzed with the RO water in the electrolysis unit 6, and the generated hypochlorous acid and hydrochloric acid are sent to the storage tank 7.
The generated water stored in the storage tank 7 is sent via the supply pump 8 to the multi-person hemodialysis system 12 connected to the generator via the motor valve 11A. The produced water sent to the multi-user hemodialysis system is
Furthermore, sterilize the piping and bedside monitor located further ahead. The electric unit 5 is for controlling the series of flows described above.

The size of the entire apparatus is 900 (W)
× 450 (D) × 1,165 (H), operating weight is 160kg, power source is AC100V × 800W, 50/6
Use 0 Hz. The production capacity is 1000 liters /
Hr, the supply pump 8 uses a magnet type, and the capacity of each tank is 100 liters of the produced water tank,
The electrolytic solution tank is 20 liters. RO water (1.5 to 2.5 kgf / cm ² ) is used as raw water. By using this generator, pH
5.0-5.5, residual chlorine concentration 50-80 ppm and O
RP 800-1000 mV of produced water was obtained.

Here, the weakly acidic electrolyzed acidic water obtained as described above is compared with the strongly acidic electrolyzed acidic water. First, FIG. 4 and FIG. 5 are compared with each other by showing the effect of organic substances on the bactericidal activity of strongly acidic electrolyzed acidic water and weakly acidic electrolyzed acidic water. In FIG. 4, 200 ml of strongly acidic electrolyzed acidic water was used at a temperature of 24.
Serum was 100 μm under conditions of 6 ° C., pH 2.39, ORP 1122 mV, and residual chlorine concentration of 25 ppm.
l, 200 μl, 500 μl and 1000 μl,
Viable cell count of each bacterium after a certain period of time (unit: CFU / ml)
Is shown. On the other hand, FIG. 5 shows 200 m of weakly acidic electrolyzed acidic water.
1 at a temperature of 24.6 ° C., pH 5.55, ORP 890
Under the conditions of mV and residual chlorine concentration of 80 ppm, 1000 μl, 2000 μl and 5000 μl of serum were added, and the viable cell count of each bacterium after a certain period of time (unit: CFU / m
1) is shown.

Also in the deactivation test with organic matter, the bactericidal effect disappeared at a concentration of 0.1% or more in the above strongly acidic electrolyzed acidic water, as is clear from FIGS. 4 and 5. In addition, weakly acidic electrolyzed acidic water is about 10 times 1%
Even the organic substances in are not deactivated. That is, it is clear that the organic matter is not easily inactivated. In addition, the amount of residual chlorine is large even in the deactivation test by storage at room temperature, and the effect is long-lasting and stable. In particular, the concentration of chlorine gas generated in the gas stored in the upper part of the storage container is about 100 ppm in the case of strongly acidic electrolyzed acidic water, whereas it is about 1 ppm in weakly acidic electrolyzed acidic water. It can be seen that chlorine is less likely to volatilize.

The metal corrosive action is also less corrosive than the strongly acidic electrolytic acidic water. That is, in the case of weak acidity, the corrosion potential is about 470 mV to 600 mV, and about 800 for the sodium hypochlorite (concentration 200 ppm).
It becomes mV, and the former has a lower corrosion potential. Therefore, for example, corrosion resistant stainless steel (SUS-316) will not corrode at normal operating temperatures. In these metal corrosivity experiments, it was found that the corrosive action became weaker in the order of sodium hypochlorite, strongly acidic electrolyzed acidic water, and weakly acidic electrolyzed acidic water. FIG. 6 shows a comparison result of the strongly acidic electrolyzed acidic water and the weakly acidic electrolyzed acidic water.

[0030]

EFFECTS OF THE INVENTION When the above weakly acidic electrolyzed acidic water is used for sterilizing and disinfecting a hemodialyzer for a single person and for a large number of people, it causes the disappearance of viable bacteria within 5 minutes, and with conventional sodium hypochlorite. It takes 60 minutes, but 20 minutes of sterilization can sufficiently achieve the purpose. In addition, in the washing time required until the residual chlorine concentration becomes 0, it took 50 minutes to perform post-washing with conventional sodium hypochlorite, but with post-washing using weakly acidic electrolytic acidic water. It is possible to greatly shorten the. And the sterilization ability was almost the same as the conventional 500-600 ppm sodium hypochlorite (pH 8.5-9.0). Further, even with respect to the effect on the wastewater septic tank, the chlorine concentration of the waste liquid in the disinfection process is low when the above-mentioned weak acidic electrolyzed acidic water is used, and the safety is higher due to the components of the electrolytically added liquid and the produced water, and their residual properties. It is a thing.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus for producing and supplying weakly acidic electrolyzed acidic water of the present invention.

FIG. 2 is a diagram showing an example of a weakly acidic electrolyzed acidic water generator, (A) is a front view, (B) is a left side view, (C) is a right side view, and (D) is a plan view. .

FIG. 3 is a diagram showing a series of flows of water and produced water in an apparatus for producing weakly acidic electrolyzed acidic water.

FIG. 4 is a diagram showing the influence of organic substances on the bactericidal activity of strongly acidic electrolyzed acidic water.

FIG. 5 is a diagram showing the influence of organic substances on the bactericidal activity of weakly acidic electrolyzed acidic water.

FIG. 6 is a diagram showing a comparison result of strongly acidic electrolyzed acidic water and weakly acidic electrolyzed acidic water.

FIG. 7 is a graph showing a graph of the abundance ratio of free available chlorine with respect to pH.

FIG. 8 is a schematic diagram showing stepwise a reaction occurring at the anode.

FIG. 9 is a schematic diagram showing stepwise secondary reactions at the anode.

FIG. 10 is a schematic view showing the reaction taking place at the cathode stepwise.

FIG. 11 is a view showing a strong acid electrolyzed acidic water sterilizing effect on serum.

FIG. 12 is a view showing the effect of sterilizing strongly acidic electrolyzed acidic water on serum.

FIG. 13 is a schematic view of a conventional device for producing strongly acidic electrolyzed acidic water.

[Explanation of reference numerals] 1 diaphragm 2, 31 anode 3, 32 cathode 4 pump motor / valve control unit 5 electric unit 6 electrolysis unit 7 storage tank 8 weakly acidic water supply pump 9 electrolysis additive tank 10, 30 electrolysis tank 11 motor Valve 12 Single or multi-person hemodialysis system 20, 40 Mixing tank

Claims (4)

[Claims] 1. An electrolytic additive solution containing a small amount of sodium chloride and chloric acid is electrolyzed in an electrolytic cell having an electrode of platinum, and the produced hypochlorous acid and chloric acid are diluted with water. Weakly acidic electrolyzed acidic water for sterilization. 2. The pH of the electrolytic acid water for sterilization is pH
The weakly acidic electrolyzed acidic water for sterilization according to claim 1, which is weakly acidic having a residual chlorine concentration of 5.0 ppm to 5.5 ppm, a redox potential of 800 to 1,050 mV. 3. A method of using the weakly acidic electrolyzed acidic water produced in claim 1 for sterilizing and disinfecting a hemodialysis apparatus for a single person and for a large number of people. 4. An electrolytic additive solution tank for storing an electrolytic additive solution containing salt and chloric acid, an electrolytic cell for electrolyzing the electrolytic additive solution sent from the electrolytic additive solution tank, and an electrolytic cell obtained by the electrolytic cell. Electrolysis unit equipped with a mixing tank for diluting hypochlorous acid and chloric acid with water, a tank for storing high-quality generated water whose pH is controlled by the generated water, and a pump for feeding the same An apparatus for producing weakly acidic electrolyzed acidic water, comprising: