JPS62262787A - Reverse contamination preventive device - Google Patents

Abstract

PURPOSE:To surely sterilize the inside of a water conduit from an apparatus for producing sterile water up to a faucet and to prevent reverse contamination by disinfecting the inside of the water conduit from the apparatus for producing the sterile water up to the faucet by the hypohalogenate generated by an electrolysis of an aq. inorg. halide soln. CONSTITUTION:This device consists of a device 2 for supplying an inorg. halide, an electrolyzing device 3 and a stop valve 4 provided to an intake. The sterile water obtd. by passing the raw water into the apparatus 1 for producing the sterile water is stored into an electrolyzing chamber of the electrolyzing device 3 by closing the valve 4 and thereafter, the inorg. halide such as sodium chloride is supplied from the device 2 into the electrolyzing chamber. Electricity is then supplied to the electrolyzing device to cause the electrolysis, by which the hypohalogenate is generated and the inside of the electrolyzing chamber and the water conduit is sterilized. As a result, the inside of the water conduit from the apparatus 1 up to the faucet is surely sterilized and the reverse contamination is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a back contamination prevention device such as a sterile water supply device. More specifically, the present invention relates to a reverse contamination prevention device that can disinfect the inside of a water conduit from a sterile water production device to a faucet with hypohalite generated by electrolyzing an inorganic halide aqueous solution.

[Conventional technology and its problems] Sterile water that does not contain impurities such as particulates and microorganisms such as bacteria is essential for medical institutions such as hospitals, medical product manufacturers, and food manufacturers. As is well known. ′ In recent years, filtration membranes that can remove microorganisms such as bacteria have been developed.
A sterile water production device that can produce sterile water relatively easily and has high reliability has been put into practical use.

However, the inside of the water conduit pipe leading to the sterile water production device and the water outlet can be contaminated by microorganisms such as bacteria floating in the air, and preventing contamination caused by such microorganisms has long been an issue.

Conventionally, as a method to prevent contamination of sterile water production equipment and the water pipes leading to the water outlet by microorganisms,
Mainly, the following four methods have been proposed.

(1) No] At the same time as the flow of sterile water from the water production equipment stops, the heater installed in the water pipe is energized, heating the water inside the water pipe and releasing it to the outside as steam, creating a path for bacteria to enter. By drying the inside of the water pipe, we prevent the growth of bacteria, and we also turn off the heater after a predetermined time has passed using a timer to prevent the inside of the water pipe from becoming negative pressure as the temperature inside the pipe falls. A heating sterilization method that seals the check valve installed at the water outlet using its own weight and external pressure to prevent bacteria from entering.

(2) A valve made of a cylindrical silicone rubber tube with an slanted circular rib integrally molded on the inside, which has an elasticity that functions to isolate it from the outside by pressing the rib from one or both directions. Elastic pinch valve method using a pinch valve.

(3) A silver vapor deposit filling method in which the faucet is filled with silver vapor deposit and the sterilizing effect of silver ions is used to prevent bacteria from entering through the faucet.

(4) Disinfection method using disinfectants such as sodium hypochlorite water.

However, in order to adopt the above (1) heat sterilization method, a complicated and large-scale device is required, which increases the cost.Also, since each part of the device is complicated, it may become contaminated with bacteria. and its disinfection is extremely difficult. Furthermore, if used for a long period of time, the check valve may become inoperable, resulting in a decrease in functionality and, ultimately, a problem in its reliability.

In the above (2) pinch valve method, the silicone rubber tube and other parts used do not have sterilization capabilities, so once bacteria enters the inside of the device, the inside of the device becomes contaminated. There's a problem.

If the above (3) silver deposit filling method is adopted, organic substances may adhere to the silver surface, reducing its bactericidal efficacy, and if a large amount of silver is eluted, drinking a large amount may cause allergies such as silver poisoning. May cause problems. Furthermore, since the bactericidal effect of silver ions is only on the faucet, the reliability of the bactericidal effect cannot be said to be high.

In addition, if the disinfection method using a disinfectant (4) above is adopted, sodium hypochlorite is a chemically unstable compound, so it is not suitable for long-term storage and is corrosive.
The problem is that it takes time and effort to disinfect, and it is extremely difficult to handle.

The inventors of the present invention have conducted extensive research to solve the problems of the conventional technology as described above, and as a result, they have been able to sterilize the inside of the water conduit from the sterile water production device to the faucet extremely efficiently and reliably. The present inventors have discovered a reverse contamination prevention device that has a simple structure, low manufacturing cost, and is easy to handle, and have completed the present invention.

[Means for solving the problem] That is, the present invention consists of an inorganic halide supply device, an electrolyzer, and a water stop valve provided at the water intake port, and it is possible to eliminate the problem by passing raw water into the sterile water production device. After the water stop valve is closed and the sterile water is stored in the electrolytic chamber of the electrolytic device, inorganic halide is supplied from the inorganic halide supply device into the electrolytic chamber and is electrolyzed to form the electrolytic chamber and the water pipe. The present invention relates to a back contamination prevention device configured to sterilize.

[Function] The back pollution prevention device of the present invention is comprised of a halide supply device, an electrolysis device, and a water stop valve provided at the water intake. If the inside of the water pipe filled with sterile water remains as it is, there is a possibility of secondary contamination due to microorganisms entering from the water intake.

In the reverse contamination prevention device of the present invention, in order to prevent this secondary contamination, the water stop valve provided at the water intake is closed to store sterile water in the electrolytic chamber, and then inorganic halide is supplied into this stored water. After injecting the inorganic halide from the device,
Electricity is applied to the electrolyzer, and the stored water containing the halide aqueous solution is electrolyzed. When stored water is electrolyzed, the halogen ions contained in the stored water become halogen molecules through anodic oxidation, and these halogen molecules further react with hydroxide to produce hypohalite.

When sodium chloride, for example, is used as the inorganic halide, the reaction formula for this series of reactions is as follows.

NaCI + H20-+ NaOH+ -H2↑+7
CI2 ↑CI! 2 +2NaOH−+NaCf0
+NaC1+) 120 Sodium hypochlorite thus produced is effective against viruses, general non-spore bacteria, acid-fast bacteria,
It is effective against most microorganisms such as bacterial spores, filamentous fungi, algae, and protozoa, and usually has the ability to complete sterilization in a short time at a concentration of about 10 ppm.

This sodium hypochlorite sterilizes the water stored in the electrolysis chamber and also sterilizes the inside of the water pipe.

Next, by opening the water stop valve and allowing the water containing sodium hypochlorite in the electrolyzer to flow out, the interior of the water conduit from the water stop valve to the faucet can also be sterilized.

[Example] One embodiment of the present invention will be described based on FIG.

In FIG. 1, (1) is a sterile water production device, (2) is an inorganic halide supply device, (3) is an electrolysis device, (4) is a water stop valve, and (6) is a water intake port.

Raw water is supplied into the sterile water production device (1) by opening the water stop valve (4), where sterile water is produced.

Examples of sterile water production equipment (1) include commonly used distilled water production equipment, pure water production equipment, ultraviolet sterilization equipment, ultrafiltration equipment, reverse osmosis equipment, heat sterilization equipment, etc., but not only these. It is possible to use Modineal, which is made of a polyethylene porous hollow fiber membrane having ultrafine pores of 1 μm vertically and 0.1 μm horizontally on the surface of the hollow fiber fibers, such as Stellaboar (registered trademark, manufactured by Mitsubishi Rayon). can.

The sterile water produced by the sterile water production device (1) is sent into the electrolysis chamber of the electrolyzer (3) by opening the water stop valve (4) provided at the water intake; The water conduit pipe between the manufacturing equipment (1) and the electrolytic chamber is equipped with water pipes to prevent changes in the concentration of the inorganic halide aqueous solution in the electrolytic chamber and to limit the range of the solution to be electrolyzed. A valve (5) may also be provided. Inorganic halide is supplied to the sterile water introduced into the electrolytic chamber from the inorganic halide supply device (2) with the water stop valve (4) closed.

As the inorganic halide supply device (2), for example, the second
An inorganic halide aqueous solution supply device having a structure as shown in the figure can be used.

That is, the bellows-type inorganic halide aqueous solution container, which is stably installed by the container stabilizing rod (21), is installed in the main body of the inorganic halide aqueous solution supply device, and the inorganic halide aqueous solution supply feed handle (to) is attached to the inorganic halide aqueous solution supply device. By turning the feed screw, the presser plate (■) moves a certain distance. This operation causes the inorganic halide aqueous solution container n
A certain amount of the inorganic halide aqueous solution is injected into the electrolytic chamber (31). In addition, in order to prevent the solution in the electrolytic chamber (31) from flowing back into the inorganic halide aqueous solution container and changing the concentration of the inorganic halide aqueous solution in the inorganic halide aqueous solution container, the electrolytic chamber (3 ) and the inorganic halide aqueous solution container may be provided with a check valve (241).

As the inorganic halide aqueous solution container, plastic containers having various shapes other than the bellows shape can be used. For example, a polyethylene bottle that can be compressed can be used, but in this case, an air valve is provided to ensure that the container returns to its original shape after supplying the inorganic halide aqueous solution. is preferable. Also, using a container with a syringe-like mechanism,
A method may be adopted in which a fixed amount of the inorganic halide aqueous solution is injected by pushing a piston a fixed length.

The concentration and amount of the inorganic halide aqueous solution to be injected into the electrolytic device (3) are determined in the electrolytic chamber (31) in the electrolytic device (3).
), it cannot be determined generally, but the concentration is usually about 0.1 to about 3.0 ml for about 10 to 40 ml of sterile water in the electrolytic chamber and water pipes.
Approximately 0.1 to 5.0 ml of 0% inorganic halide aqueous solution
Used by injection.

In the present invention, the aqueous inorganic halide solutions used include NaCJ1KC#, Ll(J, NIC1s,
NH4C1, CaCl! An aqueous solution of inorganic chloride that generates chloride ions by electrolysis such as 2, Nal
, aqueous solutions of inorganic iodides such as Kl, NaBr, KB
Examples include aqueous solutions of inorganic bromides such as NaC.
1 is preferably used.

Moreover, in the present invention, in addition to the method of injecting an inorganic halide aqueous solution into the electrolytic chamber (31) as described above,
For example, it is also possible to adopt a method of supplying a predetermined amount to the electrolytic chamber (31) using an inorganic halide exhibiting sustained release properties such as tablets or capsules formed into pellets. As the above-mentioned tablets, sustained-release tablets may be used in which the ingredients are coated with a hydrogel or the like so that the ingredients are gradually dissolved. As the hydrogel, a crosslinked 2-hydroxyethyl methacrylate polymer or copolymer is preferably used.

Alternatively, a system may be used in which sustained-release tablets are set near the electrodes and the tablets are replaced periodically depending on the lifespan of the tablets.

The inorganic halide supplied to the electrolytic chamber (31) is mixed with sterile water in the electrolytic device (3) and then electrolyzed by applying electricity to the electrodes. As for (3), for example, an apparatus having a configuration as shown in FIG. 3 can be used.

In Figure 3, two electrodes, namely an anode (32) and a cathode (33), are provided at the bottom of the electrolytic chamber (3■), and the electrolysis is carried out by applying direct current from a power source (34). .

The electrodes used for the anode (32) and cathode (33) are usually platinum electrodes, which do not undergo corrosion or other changes even when immersed in water for a long period of time, or metals such as copper and nickel, or metals such as synthetic resins. Electrodes plated or vapor-deposited with platinum or the like are used, and in order to make these electrodes easily replaceable, a cap (35) is provided with an electrode using a screw as shown in Figure 3. It may be possible to fix it.

The power source (34) is usually household AC electricity (100V
) can be transformed into direct current using a transformer, or batteries such as dry cells can be used. Further, a timer may be installed between the power source (34) and the electrodes to ensure that the power is turned on at a predetermined time.

The voltage and current of electricity applied to the anode (32) and the cathode (33), as well as the duration of the electricity, are determined in the electrolytic chamber (31).
Although it cannot be determined unconditionally because it varies depending on the type, concentration, and amount of the inorganic halide aqueous solution in the electrolytic chamber (31), for example, when NaCJ is used as the inorganic halide, the effective The chlorine concentration is adjusted to 0.5 to 500 ppm, and particularly to about 10 ppm or more in order to sterilize microorganisms such as mold.

Further, the electrolysis time using the sodium chloride aqueous solution varies depending on the concentration of the sodium chloride aqueous solution, the amount of supply, the amount of current, etc., but is preferably 10 to 120 minutes.

In addition, when the sterile water conduit pipe (3B) is installed above the electrode, the gas generated from the electrode rises to the lower end of the sterile water production device (1), and the generated gas causes hypohalite Since the contained water and sterile water are stirred, it is preferable to have such a structure.

The stirring effect of such a gas becomes much greater when the electrolytic voltage is high. Therefore, if the sodium hypochlorite concentration at the upper end of the water conduit pipe is to be increased and the sterilizing ability of this portion is to be enhanced, the sodium chloride concentration in the electrolytic chamber may be lowered and/or the electrolytic current may be increased.

The above-mentioned energization is usually carried out when sterile water is allowed to remain in the electrolytic chamber and the water pipe for a long time, such as at night, and does not need to be carried out during use because bacteria will not grow in the water pipe.

It is usually preferable to use an electromagnetic valve as the water stop valve (4), but if an elastic pinch valve is used, for example, as described in JP-A No. 57-9386, intrusion of microorganisms from the outside can be prevented. This is particularly desirable. The water stop valve (4) is used when injecting an aqueous inorganic halide solution into the electrolysis chamber (31) from the inorganic halide supply device (2) and when injecting a mixed solution of the injected aqueous inorganic halide solution and sterile water. Closed when disassembling as well as when sterile water is not used.

After the electrolysis is completed, when the water stop valve (4) is opened without supplying sterile water from the sterile water production device, the sterile water containing hypohalite stored in the electrolytic chamber (31) is released. Since the inside of the water pipe and the faucet are cleaned, bacteria adhering to the water pipe are sterilized. After releasing an appropriate amount of hypohalite-containing water, the water stop valve (4) is closed. It is also possible to open the water stop valve for a short time to allow the chlorine-containing water to flow out and close the water stop valve, and to hold the chlorine-containing water for a certain period of time before opening the water stop valve (4) after electrolysis is completed.

The reverse contamination prevention device of the present invention configured as described above sterilizes the inside of the water conduit from the sterile water production device to the faucet by going through the flow chart of the sterilization process as shown in FIG. 4 or 5. , back contamination is prevented.

That is, in FIG. 4, an inorganic halide is supplied from an inorganic halide supply device to an electrolytic chamber of an electrolytic device,
Next, the inorganic halide aqueous solution is electrolyzed. After the electrolysis is completed, the water stop valve is opened for several seconds to several tens of seconds, and after the high concentration hypohalite-containing water flows out from the water intake port, the water stop valve is closed.

Further, in FIG. 5, an inorganic halide is supplied from an inorganic halide supply device to an electrolytic chamber of an electrolytic device, and then the inorganic halide aqueous solution is subjected to M gas decomposition. After electrolysis, the hypohalite-containing water obtained is held for 10 to 60 minutes, then the water stop valve is opened for several seconds to several tens of seconds, and the highly concentrated hypohalite-containing water is discharged from the water intake. After draining, the water stop valve is closed.

If the reverse contamination prevention device is not used for a long time, such as at night, store chlorine-containing water as shown in Figure 6, and open the water stop valve a little before 9 o'clock to turn off the water. After draining water containing a high concentration of hypohalite from the water intake,
Preferably, the water stop valve is closed.

Next, the present invention will be explained in more detail based on experimental examples and examples, but the present invention is not limited only to these experimental examples and examples.

Experimental Examples 1 to 6 Open the water stop valve, inject tap water into the sterile water production device to produce sterile water, and send it to the electrolytic chamber with an internal capacity of 30 m1, then close the solenoid valve and fill the electrolytic chamber with sterile water. was stored.

Next, an aqueous sodium chloride solution was injected into the electrolytic chamber under the conditions shown in Table 1, electricity was applied to the two electrodes, and the chlorine concentration in the electrolytic chamber was measured after 60 minutes had elapsed. The results are also listed in Table 1.

[Margins below] Example 1 0.5 ml of the inoculum solution cultured by the method detailed below was inoculated into 30 ml of sterile water in the pipe, and the number of inoculated bacteria was added to the electrolytic chamber using a syringe (for 1 ml). 105-106
cells/ml. Next, 0.5 ml of an aqueous sodium chloride solution having a concentration of 10% was injected into the electrolytic chamber using an inorganic halide supply device, and a DC current of LOmA was applied to the two electrodes to perform electrolysis for 60 minutes.

After electrolysis, after draining the water containing sodium hypochlorite, sterile water was passed through a sterile water production device (Stella Boar, manufactured by Mitsubishi Rayon ■), sampled from the faucet, A sterility test was conducted based on "Test method 37. Sterility test method". Judgments were made by culturing at 30°C for 7 days for bacterial tests and 10 days at 20°C for fungal tests. The results are shown in Table 2.

The inoculum was prepared using the following method.

(Preparation of inoculated bacteria) Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger were used as inoculated bacteria.Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa were cultured at 35°C for 24 hours and then incubated for 3 consecutive days. For Candida albicans, after culturing at 25°C for 48 hours, two
Aspergillus niger was cultured at 25°C for one week.

For Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans, a bacterial solution with a bacterial count of 108 cells/ml was prepared after washing with sterile physiological saline three times in a centrifuge at 3000 rpm for 10 minutes.

Also, for Aspergillus niger, 0.05%
A spore suspension was prepared using sterile physiological saline containing polysorbate 80, and centrifuged at 300 rpm 1.
After washing 3 times for 0 minutes, resuspend using sterile physiological saline.
A bacterial solution of 107 cells/ml [blank below] As can be seen from the above results, secondary contamination between the outlet side of the sterile water production device and the faucet is completely prevented by the back contamination prevention device of the present invention. This means that you can always get sterile water from the faucet.

[Effects of the Invention] As described above, according to the back contamination prevention device of the present invention, the inside of the water conduit from the sterile water production device to the faucet can be reliably sterilized and back contamination can be prevented. It is simple and extremely easy to handle.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is an explanatory diagram of the back pollution prevention device of the present invention, FIG. 2 is a schematic explanatory diagram of the inorganic halide supply device, FIG. 3 is a schematic explanatory diagram of the electrolytic device, and FIG. Figures 5 and 6 show flowcharts of the sterilization process. (Main symbols on the drawings) (2), Inorganic halide supply device (3): Electrolytic device (4); Water burial patent applicant Tomey Sangyo Co., Ltd. and one other person

Claims (1)

[Claims] 1. Consisting of an inorganic halide supply device, an electrolytic device, and a water stop valve installed at a water intake port, the sterile water produced by passing raw water through the sterile water production device is water-stopped. After the valve is closed and water is stored in the electrolytic chamber of the electrolytic device, an inorganic halide is supplied from an inorganic halide supply device into the electrolytic chamber and electrolyzed, thereby sterilizing the electrolytic chamber and the water pipe. Back pollution prevention device. 2. The back pollution prevention device according to claim 1, wherein the water stop valve is an elastic pinch valve. 3. The back pollution prevention device according to claim 1, wherein the water stop valve is configured to be opened for a certain period of time after electrolysis is completed. 4. The back contamination prevention device according to claim 1, wherein the inorganic halide supply device is configured to supply a fixed amount of inorganic halide. 5. The back contamination prevention device according to claim 1, wherein the inorganic halide is sodium chloride. 6. The reverse contamination prevention device according to claim 1, wherein the inorganic halide exhibits sustained release properties in water. 7. The back contamination prevention device according to claim 1, wherein the inorganic halide is an aqueous solution.