JP2000126775A - Method and apparatus for electrolytic sterilization - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems of the stop of ions produced by electrolysis and to produce sterilizing metal ions stably and efficiently by supplying a larger amount of electric current intermittently between electrodes as compared with a case in which the current is supplied continuously for electrolysis when ions are produced in a raw solution in an electrolytic cell. SOLUTION: The inflow of raw water 31 is detected, and a direct current is supplied to a positive pole side terminal 23 and a negative pole side terminal 26. On the positive pole side, the current is passed to a positive pole side electrode 21 via a positive pole side conductive electrode 22, an anode reaction of the electrode 21 is generated, and ions produced by electrolysis elute from the electrode 21. In the opposite negative pole, it is passed from the terminal 26 to a negative pole side electrode 24 via a negative pole side conductive electrode 25, and a scale deposition reaction such as a hydrogen gas generation reaction of hydrogen ions in the raw water 31 progresses. Electrolyzed water 32 from a housing 40 contains electrolysis-produced ions generated on the positive pole side to make electrolytic water. The application and stop of electrolysis are repeated, and the electrolysis is stopped by a stop command by an amperage switch and others.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for sterilizing by electrolysis and an apparatus using the method.

[0002]

2. Description of the Related Art Conventionally, chlorine sterilization is most often used as a method for sterilizing water, as seen in disinfection in waterworks.
This chlorine sterilization acts on the cells at a low concentration and can be sterilized almost instantaneously, which is a very effective sterilization means.

However, since chlorine gradually decomposes in water, its bactericidal effect tends to be weakened. Therefore, the chlorine generation is generated at a high concentration by electrolysis of a saline solution, added to water, diluted to a required concentration, and used.
However, chlorine chemically reacts with organic matter in the water to produce toxic trihalomethane, in addition to more significant consumption. Chlorine is administered to a large amount of organic substances, such as middle water and landscape water, which contain more organic substances than tap water, to generate a large amount of trihalomethane.

[0004] For this reason, there is a method using sterilizing metal ions as another sterilizing method. Typical examples thereof include silver ions and copper ions contained in antibacterial materials. Since the bactericidal metal ion is more stable than chlorine, it has a sustained bactericidal effect and does not generate harmful substances such as trihalomethane.

[0005] Disinfection of germicidal metal ions is carried out by forcibly applying a DC power supply, whereby metal ions are eluted from the positive electrode according to Coulomb's law. The bactericidal metal ion concentration has the advantage that it can be easily controlled by the amount of water to be sterilized and the electric current. As an operation method, a cation such as a Ca ion or a K ion adheres to the negative electrode, and so-called adhesion of scale occurs.

As an example, FIG. 2 shows an example of reverse power operation in which current is switched for each use cycle to operate. One cycle is defined as one cycle from when the bactericidal metal ion is required until it becomes unnecessary. During one cycle, a predetermined current is applied to the germicidal metal to produce germicidal ion-containing water. Part 1
When the cycle is completed, the application of the current is stopped.
At the beginning of the next cycle, the opposite pole from the previous cycle is +
It is intended to be a pole. As another example, the power may be reversed after a predetermined number of cycles. This reverse voltage is often used in chlorine generating electrodes and other electrolysis methods.

[0007]

However, according to the prior art, the scale attached to the negative electrode is firmly fixed to the electrode with use and cannot be sufficiently removed, and the production capacity thereof gradually decreases. In addition, even after the completion of one cycle of electrolysis, since a voltage of several volts remains between the electrodes, the original ions of the scale component in the water gradually deposit on the electrode surface. Thus, there was a problem that the dissolution of the germicidal metal ions was gradually stopped due to the scale. As an example, when the application is performed in the operation pattern of FIG. 2 in FIG. 4, the Ag ion concentration of the germicidal metal ion gradually decreases and finally the metal ion concentration is not detected.

SUMMARY OF THE INVENTION The present invention has been made to solve the problem of stopping electrogenerated ions, and has as its object to provide a method and apparatus for stably and efficiently producing germicidal metal ions. .

[0009]

According to the present invention, there is provided an apparatus provided so that a predetermined amount can be subjected to an electrolytic reaction and a predetermined concentration can be stably maintained. The electrode for performing the electrolytic reaction is provided on the back side of the electrode catalyst metal where the insoluble conductive material connected to the external electrode terminal performs the electrolytic reaction, and is connected. The game side is similarly configured. When the electrolysis reaction is required, the application is performed with a current higher than that at the time of the continuous energization, and the application and the stop are repeated several times until one cycle is completed. Preferably, both poles can be short-circuited during the stop to further increase stability. In addition, continuous energization means that electrolysis is not stopped during application as shown in FIG. 2, and is distinguished from repetition of application and stop of the present invention.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the electrolytic sterilization method and apparatus according to the present invention, the electrocatalyst electrode for performing an electrolytic reaction performs current application and current stop during one cycle, and the electrolysis reaction current is higher than in the case of continuous electrolysis. React with high current. The electrode is a chlorine producing electrode in the case of hypochlorite ion as a germicidal ion, and Ag, C in the case of germicidal metal ion.
Electrodes of u, Fe, Co, Zn, Sn, Zn and the like are effective.

[0011] The operation method is started by receiving an electrolysis start signal. At the plus electrode, which was the minus pole in the previous cycle, the attached scale component elutes and the electrode surface is cleaned, and the electrolytic production proceeds. Next, the electrolysis is temporarily stopped, and the electrolysis is repeated. While the electrolysis is stopped, the removal of some scale proceeds by the flow. In order to further enhance the scale removal effect, the electrodes may be short-circuited with the counter electrode while the current is stopped, or may be short-circuited between the end of one cycle and the next cycle. It is possible to prevent calcium ions, potassium ions, and the like, which are the source of scale components in the liquid, from being attracted to the electrode surface by the voltage remaining in the electrode and becoming a scale. By repeating the above, the electrode reaction always reacts stably, and the electrolytic operation can be performed for a long time.

In particular, when germicidal metal ions are eluted, the electrodes are gradually consumed as the germicidal metal ions are eluted. An insoluble conductive electrode such as a titanium plate is provided on the back side of the consumable electrode. Since they are connected so as to be short-circuited, the electrodes can be used until the end, and the electrodes can be used without waste until the end.

[0013]

The present invention will be described in more detail with reference to the following examples. FIG. 1 is a diagram showing a schematic configuration of an electrolysis apparatus 10 according to one embodiment of the present invention. The electrolytic device 10 of the present embodiment
The electrolytic reaction is caused by water flowing between the electrode 21 and the electrode 24. Hereinafter, the configuration of the electrolysis apparatus 10 will be described.

The electrolysis apparatus 10 comprises a connection port for pre-electrolysis water 31 and post-electrolysis water 32, and a housing 40 provided with a positive terminal 23 and a negative terminal 26. The pre-electrolysis water 31 may be clean water, middle water, or waste water. In addition, since the positive electrode terminal 23 and the negative electrode terminal 26 are switched and used during the electrolysis or every time the electrolysis under the predetermined conditions is completed, they are provisional positive and negative electrodes.
In the housing 40, a positive electrode 21 and a positive conductive electrode 22 provided so as to be short-circuited with the positive electrode 21 are provided. Similarly, a counter electrode is composed of a negative electrode 24 and a negative electrode 25. A gap is provided between the positive electrode 21 and the negative electrode 24 so as not to cause a short circuit. When the electrode is large, a spacer or the like may be interposed.

Next, the operation of the present apparatus will be described. The operation detects the inflow of the pre-electrolysis water 31 using a flow switch or the like, and supplies a direct current to the + terminal 23 and the − terminal 26. On the positive electrode side, a current flows through the positive electrode 21 via the positive electrode 22, an anodic reaction of the positive electrode 21 occurs, and electrolytically generated ions are eluted from the positive electrode 21. For example, if it is a chlorine generating electrode, hypochlorite ion,
In the case of a sterilizing metal electrode, Ag ions and Cu ions are used. In the counter electrode, a so-called scale such as a hydrogen gas generation reaction of hydrogen ions in the pre-electrolysis water 31 or a Ca ion or a K ion passes from the negative electrode terminal 26 through the negative electrode conductive electrode 25 to the negative electrode 24. The adhesion reaction proceeds. The post-electrolysis water 32 coming out of the housing 40 becomes electrolyzed water because it contains electro-generated ions generated on the positive electrode side.
The electrolysis operation conditions are, for example, an electrolysis application time of 10 seconds and a stop time of about 10 seconds.

If the time is too short, the generation efficiency of the electrolytically produced ions decreases. During electrolysis, repeat the process,
The electrolysis is stopped when a stop command is received by a flow switch or the like. During the stop, the + station and the − station may be short-circuited and discharged. When the start signal is detected again by the flow switch or the like after the completion of the above-described one cycle, + and-are applied to the opposite pole to the previous one. The application conditions at that time are the same as in the above case.

-The scale adhesion reaction proceeds on the electrode side, but the scale growth is temporarily stopped by stopping the electrolysis on the way, and the scale is separated by the flow. When the applied time is, for example, 10 seconds for the electrolysis time and 10 seconds for the stop time, the current flows about twice as much as in the case of continuous application. In particular, in the case of germicidal metal ions, the flowing current is as small as several tens of mA, and it is preferable to flow a strong current because the reverse voltage alone does not cause separation.

FIG. 5 shows the daily change of the bactericidal metal ion (Ag ion) concentration when the operation of the present invention is added. In this case, the electrolysis time is 10 seconds, the stop time is 10 seconds, and one cycle is 60 seconds. On the other hand, FIG. 4 shows the daily change of the bactericidal metal ion (Ag ion) concentration when the conventional operation is performed. Clearly, the conventional reverse voltage of FIG.
The ion concentration gradually decreased, and after about 50 days, the Ag ion concentration was no longer detected. However, in the present invention shown in FIG. 5, the Ag ion concentration was maintained from the beginning.

In the case of a sterilizing metal electrode, the positive electrode 21 is consumed and becomes thinner with use. Although the thinning does not uniformly consume the entire electrode surface, the sterilizing ions continue to elute even when the positive electrode 21 is divided by the conductive electrode. Here, the positive electrode side is described, but as described above, the electrolysis conditions may be used by switching the polarity. Further, although the electrode is described as using the same material on both the positive electrode side and the negative electrode side, only one electrode may be used as an electrogenerated electrode and the other electrode may be an electrode which does not participate in the reaction. Further, the electrode may be a material hybrid.

[0020]

As described above, according to the present invention, it is possible to solve the problem that the electroformed ions are stopped, stably produce germicidal metal ions, and use the germicidal electrode efficiently to the end. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of an electrolytic sterilization apparatus according to the present invention.

FIG. 2 is a diagram of an example showing a time change of a conventional current application condition.

FIG. 3 is a diagram showing an example of a time change of a current application condition in the present invention.

FIG. 4 is a diagram showing a change in Ag ion concentration when a conventional current is applied.

FIG. 5 is a diagram showing a change in Ag ion concentration when a current is applied in the present invention.

[Explanation of symbols]

10 electrolyzer 21 ... + electrode side electrode, 22 ... + electrode side conductive electrode, 23 ... +
Pole side electrode terminal 24 ...- Pole side electrode, 25 ...- Pole side conductive electrode, 26 ...-
Pole side terminal 31: Water before electrolysis, 32: Water after electrolysis 40: Housing

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C02F 1/50 540 C02F 1/50 540B 560 560F

Claims (7)

[Claims] In an electrolytic sterilization method for generating and sterilizing ions in a liquid to be treated by electrolysis, the method comprises the steps of: providing at least one electrode for generating the ions; and providing at least one pair of electrodes in an electrolytic cell. When the ions are generated in the liquid to be treated in the tank by electrolysis, a step of repeatedly applying and stopping between the electrodes and applying a larger current than in the case of performing electrolysis by continuous energization is performed. Electrolytic sterilization method. 2. The electrolytic sterilization method according to claim 1, wherein, in the step of repeatedly applying and stopping the application, the electrodes are short-circuited while the application is stopped. 3. The electrolytic sterilization method according to claim 3, wherein the electrode comprises a chlorine generating electrode. 4. The electrolytic sterilization method according to claim 3, wherein the electrode comprises an electrode for generating a bactericidal metal ion. 5. The electrolytic sterilization method according to claim 5, wherein the germicidal metal ion is a silver ion. 6. An electrolytic sterilizer using the electrolytic sterilization method according to claim 1. 7. The electrolytic sterilizer according to claim 6, wherein the germicidal ion-containing water generated by the electrolytic sterilizer is used for a toilet or watering.