JPH1110156A - Method for regenerating porous carbon electrode of water purification and disinfection apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for regenerating a porous carbon electrode of a water purification and disinfection apparatus comprising an electrolytic tank containing a porous carbon electrode in which a regenerating means to constantly maintain powerful disinfection performance and prevent deterioration of the performance of the electrolytic tank containing a porous electrode is so installed as to be automatically driven. SOLUTION: This method is for regenerating a porous carbon electrode of a water purification and disinfection apparatus which repeats water treatment cycles comprising a normal use process carried out by bringing raw water introduced into an electrolytic tank comprising a porous carbon electrode 1 through a water supply pipe into contact with the porous carbon electrode 1 to which voltage for disinfection polarization is applied and taking out the resultant purified water out of a purified water pipe 185 to use the purified water and a regeneration process carried out by discharging raw water stored in the electrolytic tank out of a water discharge pipe 154 and regenerating the disinfecting efficiency of the porous carbon electrode. The regenerating process comprises a separation process of separating adsorbed constituents adhering to the porous carbon electrode by heating the porous carbon electrode to a prescribed temperature by controlling applied voltage while discharging raw water stored in the electrolytic tank and a discharge process of discharging the desorbed absorbed constituents and emitted gas through a water discharge pipe 154 to outside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purification apparatus for purifying raw water such as tap water and groundwater and supplying it as drinking water for general household use and business use. The present invention relates to a method for regenerating a porous carbon electrode of a water purification apparatus having a regenerating function capable of automatically controlling the capacity and regenerating.

[0002]

2. Description of the Related Art At present, various kinds of water are used in our daily lives. For example, well water, tap water, industrial water, pure water, ultrapure water, bathtub water, pool water, etc. In particular, in drinking water, water purifiers for purifying tap water and well water have become extremely popular due to recent health-conscious influences. Activated carbon is used in water purifiers in particular, and this allows harmful substances such as trihalomethane in tap water,
It contributes to providing safe and delicious water by removing the unpleasant odor of chlorine.

[0003] Further, drinking water is supplied to households, drinking shops and the like through waterworks after disinfecting water stored in a water source such as a reservoir at a water purification plant. The disinfection of drinking water is generally treated with chlorine, but according to the chlorination, drinking water is disinfected relatively well, but the mellowness of natural water is impaired due to the smell of chlorine. Disadvantages arise.

[0004] As a water treatment method which does not have the above-mentioned disadvantages, for example, Japanese Patent Application Laid-Open Nos. 3-224686 and 4-274.
No. 88, etc., there is a method of electrochemical treatment. According to this method, a large amount of water can be treated without using a special chemical or the like.

[0005] However, especially in the means for removing chlorine such as activated carbon in a water purifier, bacteria proliferate while the treated water such as tap water stays, resulting in a decrease in biological water quality. Therefore, the number of general bacteria, which is the standard for tap water, is 100 CFU / ml.
A certain amount of discarded water was required at the time of resuming use of the water purifier in order to:

[0006]

As described above, it is possible to remove harmful substances, chlorine odor and the like in clean water (tap water) and well water by passing through a filtration tank using activated carbon or the like. However, since bacteria and bacteria such as molds re-grow during pause, the problem has been solved by passing the same through an electrolytic cell using a porous carbon electrode as an electrochemical treatment. However, even if such an electrolytic cell is not used for a long time without passing clean water or well water, and even if it is used frequently, if the use period is too long, the number of bacteria increases or dead bacteria and foreign matter are removed. However, there has been a problem that the germicidal effect and the water purifying effect are reduced due to accumulation in the porous carbon electrode.

According to the present invention, a regenerating means for automatically maintaining a strong sterilizing ability without reducing the function of the porous carbon electrode electrolytic cell automatically works so that such inconvenience does not occur. An object of the present invention is to provide a method for regenerating a porous carbon electrode of a water purification apparatus using a porous carbon electrode electrolytic cell.

[0008]

This object is achieved by any one of the following technical means (1) to (3).

(1) Raw water introduced into a porous carbon electrode electrolytic cell by a water supply pipe is brought into contact with a porous carbon electrode to which a sterilizing polarization voltage is applied to purify and sterilize the raw water, and the purified water is supplied to the outlet side of the electrolytic cell. Water purification sterilization that repeats a cycle consisting of a normal use step of taking out and using the provided water purification pipe and a regeneration step of draining raw water stored in the electrolytic tank from a drain pipe and regenerating the sterilization efficiency of the porous carbon electrode. A method for regenerating a porous carbon electrode of an apparatus, wherein the regeneration step comprises closing a water supply valve and opening a drain valve of a raw water by a time-up signal indicating that the normal use step has been completed, thereby obtaining raw water from a raw water supply source. Is passed through an aspirator provided in the drainage pipe, and the pressure is reduced by suction to drain the raw water stored in the electrolytic cell. A draining step of applying a power supply circuit voltage for heating and regeneration to the elementary electrode, and draining until it is detected that the rate of change δ1 of the resistance or voltage due to the change in electrical resistance of the porous carbon electrode has reached the set rate of change δa; In the drainage step, the water supply valve is closed with the control signal indicating that the set change rate δa has been reached, the drainage valve is closed, and the applied voltage is controlled to heat the porous carbon electrode to a predetermined temperature and adhere. A desorption step of desorbing the adsorbed component, and when the rate of change δ2 of resistance or voltage due to a change in electric resistance of the porous carbon electrode reaches the set rate of change δb in the desorption step, this is detected and controlled. The signal is applied to the porous carbon electrode to reduce the applied voltage to a predetermined weak voltage to continue heating, and the operation signal indicating that the set change rate δb has been reached. To In addition, an exhaust step of introducing raw water from the raw water supply source into the aspirator through the bypass pipe to suction and decompress the inside of the electrolytic cell, and discharging the desorbed adsorption component and generated gas from the drain pipe to the outside, A method for regenerating a porous carbon electrode in a water purification and sterilization apparatus, comprising:

(2) While the set change rate δa is being obtained in the draining step or the set change rate δb is being obtained in the desorption step, the detection voltage of the porous carbon electrode is set to the set voltage V
s is determined to be the time to replace the porous carbon electrode when the value exceeds s, the method for regenerating the porous carbon electrode of the water purification apparatus according to item (1), wherein

(3) Completion of the drainage process, desorption process, and exhaust process in the water purification / sterilization device is detected by a preset time count, and a regeneration process consisting of drainage, desorption, and exhaust is optionally performed. The method for regenerating a porous carbon electrode of a water purification apparatus according to item (1), wherein the method is performed at time intervals.

The introduced raw water permeates into and contacts the porous pores of the porous carbon electrode. Bacteria in the raw water are removed by an applied voltage suitable for sterilization polarized in the electrode,
Sterilized, most of the carcasses are washed away. The purified water is used for drinking water through a water purification pipe.

In the method for regenerating a porous carbon electrode according to the first aspect of the present invention, a cycle consisting of a normal use process and a regeneration process is repeated. When the water supply valve is closed and the drain valve is opened, the raw water from the raw water supply source is bypassed and passed through the aspirator, and the raw water stored in the electrolytic cell is drained by suction and pressure reduction. During drainage, a power supply circuit voltage for heating and regeneration is applied to the porous carbon electrode, and drainage is performed until it is detected that the rate of change δ1 of the resistance or voltage due to the change in electrical resistance of the porous carbon electrode has reached the set rate of change δa. .

Next, in the desorption step, the end of the drainage step is determined by detecting that the change rate δ1 has reached the set change rate δa in the previous drainage step, and the operation signal from the control device is used to determine the end of the drainage step. The drain valve is closed with the water supply valve closed. At the same time, the voltage applied to the heating / regeneration power supply circuit is increased to heat the porous carbon electrode to a predetermined temperature by Joule heat. The voltage application time to the power supply electrodes 4 and 4 'for energization and heating is set in advance (T ₂ ), and when the energization time (t ₂ ) has reached this, it is determined that the desorption process has ended. Then, the process proceeds to the exhaust process. Further, while the voltage is being applied, the temperature of the porous carbon electrode is detected, and a predetermined range (C ₁ −ΔC <C <C ₁ ; Δ
C repeats the ON-OFF operation of applying the voltage to the power supply electrodes 4 and 4 'so as to maintain the temperature differential).
Control the temperature of the porous carbon electrode. This control is continued until a predetermined time (T ₂ ) is exceeded.

Finally, in the evacuation process, the drain valve is opened with the water supply valve closed in accordance with an operation signal from the control device. As a result, raw water is introduced from the raw water supply source into the aspirator through the bypass pipe, and the inside of the porous carbon electrode electrolytic cell is suctioned and decompressed, and foreign matter such as dead bacteria and desorbed gas and the generated gas are exhausted from the drain pipe to the outside. It is detected whether the evacuation time in this evacuation step has also exceeded a preset time (T ₃ ),
The control method for preventing abnormal heating of the porous carbon electrode is the same as in the above-described desorption step.

The cycle of the desorption step and the evacuation step is repeated. After the evacuation step is completed, the voltage applied to the porous carbon electrode is reduced to a predetermined weak voltage, and the resistance or voltage change due to the electric resistance change of the porous carbon electrode is performed. Rate δ2 and set voltage change rate δb
Compare with If the set value is not reached, it is determined that the desorption is insufficient, and the desorption process is restarted. If it has reached, the desorption and exhaust are all determined to be completed, and the process shifts to a normal use process.

On the other hand, according to the invention of claim 2, while the set change rate δa is obtained in the exhaust step or the set change rate δb is obtained in the desorption step,
When the detection voltage of the porous carbon electrode exceeds the set voltage Vs, it is determined that it is time to replace the porous carbon electrode.

Further, according to the third aspect of the present invention, a regeneration step including drainage, desorption, and exhaust is performed at an arbitrary time interval,
Each mode of the regeneration process can be performed at optimal time intervals.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
FIG. 1 is a schematic cross-sectional view of a water purification apparatus 100 using a porous carbon electrode electrolytic cell (hereinafter sometimes simply referred to as an electrolytic cell) to which the regeneration method of the present invention is applied. The fixed bed type three-dimensional electrode (porous carbon electrode) electrolytic cell EC is provided between a pair of plate-like power supply electrodes 4, 4 ', preferably a mesh-like electrode, and one or more preferably 1 to 15 porous carbon electrodes ( A fixed-bed type three-dimensional electrode) 1 is arranged, and the pair of power supply electrodes 4 and 4 ′ are provided.
The fixed bed type three-dimensional electrode (porous carbon electrode) 1 is polarized by applying a DC voltage to the electrode, and the fixed bed type three-dimensional electrode (porous carbon electrode) 1 is subjected to electrolytic treatment by passing water to be treated. This is a water treatment apparatus that removes or sterilizes microorganisms such as bacteria, viruses, and protozoa. Alternatively, it can also be used for removing metal components in the water to be treated and electrochemically removing impurities.

As the porous carbon electrode, porous carbon graphite, porous glassy carbon and the like are preferably used.

In the treated water, microorganisms such as bacteria (bacteria), filamentous fungi (fungi), yeast, deformed bacteria, single-cell algae, protozoa, and viruses are sterilized in the treated water to improve the water quality. . That is, when the water to be treated is supplied to the fixed bed type three-dimensional electrode (porous carbon electrode) electrolytic cell EC, the microorganisms in the water to be treated are caused to flow by the liquid flow, and the fixed bed type three-dimensional electrode of the electrolytic cell, the power supply electrode, etc. It is considered that these substances are contacted and adsorbed, undergo a strong oxidation-reduction reaction on their surface, or come into contact with a high-potential electrode, and their activities are weakened or they are killed and sterilization is performed. When the electrolytic cell EC is used for reforming the water to be treated, the applied potential is set to +0.2 to +1.2 V (vs. SCE) where the anode potential does not substantially involve oxygen generation, and the applied potential is substantially the cathode potential. 0--1.0V without hydrogen generation
(Vs. SCE),
A higher anode potential can be applied when the substance in the liquid does not undergo an oxidation-reduction reaction and the liquid property does not change, or when the amount of reaction does not matter much. For example, a voltage equivalent to 2.5 to 6 V can be applied to one step of the porous carbon electrode. For example, a 1 mm thick titanium mesh electrode plated with platinum is provided on both sides of a 9 mm thick porous carbon electrode to form a fixed bed. In the case of an electrolytic cell in which the distance between the mesh electrode and the power supply electrode is 1 mm, a voltage of about 20 to 50 V can be applied to the power supply electrode. Approximately 1 when 5 layers are stacked under the same conditions
A voltage of 3 to 30 V can be applied to the power supply electrode.

In addition to the above-described direct sterilization, Joule heat can be generated by applying a specific voltage between the power supply electrodes using the porous carbon electrode and the raw water contained therein as a resistor.

For power supply, a constant voltage generator for converting alternating current to direct current, or a battery such as a dry battery or a storage battery can be used. Ca, M contained in the water to be treated
In order to prevent components such as g and Si from depositing on the electrodes, the electrode terminals 11, 11 'are spaced at intervals of about 1 to 60 minutes.
It is desirable to reverse the polarity of the voltage applied to. This can prevent components such as CaCO ₃ , Mg (OH) ₂ and SiO ₂ from adhering.

These include, for example, a plurality of sheets made of vegetable fibers, such as Japanese paper, laminated by using an organic binder, are heat-treated at a temperature of 1000 ° C. or more in an inert gas atmosphere, carbonized, and further heat-treated to obtain glassy carbon. This is a porous carbon electrode plate. A phenol resin, an epoxy resin, or the like can be used as an organic binder used for such a purpose, but the organic binder is not particularly limited to these. For example, Japanese Patent Application Laid-Open Nos. 61-12918 and 61-236664.
No. 61-236665, JP-A-2-199011
No. 8,173,972 and 8-126888 can be used as the porous carbon electrode used in the present invention. It is also possible to arrange a plurality of these porous carbon electrodes 1 in one gasket 3. For example, one piece of porous graphite having a thickness of 9 mm and an average pore diameter of 50 μm may be used, or three pieces of porous graphite having a thickness of 3 mm and an average pore diameter of 50 μm may be used. Further, the pore diameter and thickness can be arbitrarily changed.
μm, and porous graphite having an average pore diameter of 50 μm is sandwiched and set on both sides thereof, and a stack of these three pieces can be used as one fixed-bed type three-dimensional electrode 1. The plurality of stacked fixed-bed type three-dimensional electrodes (porous carbon electrodes) 1 are accommodated in a tubular body 6 having upper and lower ends open, and a lid 10 is placed thereon. The tubular body 6 is preferably formed of an electrically insulating material that can withstand long-term use or re-use. Particularly, polyepichlorohydrin, which is a synthetic resin,
Polyvinyl methacrylate, polyethylene, polypropylene, polyvinyl chloride, polyvinyl chloride, phenol-formaldehyde resin, ABS resin, acrylic resin,
Polycarbonate, Teflon resin and the like can be used. Further, it is more convenient to form the fixed-bed type three-dimensional electrode 1 by using a transparent or translucent material, because the assembled or worn state of the fixed-bed type three-dimensional electrode 1 can be visually recognized. Preferably, a material having high heat resistance such as a polycarbonate resin is preferable. Alternatively, an insulating coating or a metal such as stainless steel coated with an insulating coating can be used. Thus, hot water can be generated in the electrolytic cell or passed through the electrolytic cell, and sterilization and disinfection in the apparatus can be easily performed.

A part (preferably, the center) of the bottom plate 18
Is provided with a thermistor 170 as a temperature sensor,
The temperature of the water and porous carbon electrode sealed and heated in the vessel 86 of the electrolytic cell can be detected. Also,
An inlet 15 for raw water such as tap water or well water is attached to the bottom plate 18, and a power supply electrode terminal 11 'is provided insulated. In addition, the lid 10 provided with the bottom plate 18 and the other power supply electrode terminal 11 is attached to the cylindrical body 6 to form an electrolytic cell container 86.

FIG. 2 is a schematic cross-sectional view of another embodiment of the water purifying and sterilizing apparatus. An electrolytic cell EC is an electrolytic cell container 86 composed of an outer tube 6, an inner tube 5, a bottom plate 18, and a lid 10. The porous carbon electrode and the like are housed in the inner cylinder 5 and the water flowing from the upper raw water inlet 15 such as tap water or well water between the inner cylinder 5 and the outer cylinder 6 is The water flows through the porous carbon electrode 1 from below, and flows from a purified water outlet 16 provided above to a discharge port (not shown). And bottom plate 1
Reference numeral 8 is fixed to the lower part of the inner cylinder 5 and the outer cylinder 6, and a thermistor 170 as a temperature sensor is attached to the bottom plate 18. Further, since the power supply electrode terminals 11 and 11 'are also provided above the container 86 of the electrolytic cell, the bottom plate 18 is provided.
There is nothing else attached to the simplification of the structure.
Further, a filter material can be packed in the water passage between the inner cylinder 5 and the outer cylinder 6 and can be used more effectively.

It is also preferable for the heating means that the inner cylinder 5 and the outer cylinder 6 be made of a metal material whose outside is covered with a heat insulating material or an electrically insulating material instead of a resin material.

The cylindrical body 6 or 5 shown in FIG. 1 or FIG.
The porous carbon electrode (fixed-bed type three-dimensional electrode) 1 is prevented from being detached, that is, dropped from the cylindrical body, by installing a support so as to close a part of the lower or upper opening. it can. The shape of the support is not particularly limited as long as the support has sufficient strength to suppress the movement of the plurality of porous carbon electrodes. Also, a screw may be carved in the donut-shaped body and the cylindrical body, and both members may be screwed and fixed to each other. Furthermore,
Similarly, a support or a spacer can be provided on the upper portion of the opening by screwing, and the porous carbon electrode can be accommodated in the cylindrical body 6 or 5 in a more stable state. Donut-shaped spacers 9, 9 ', 9 "can be provided at the electrode intervals set in the cylindrical body to maintain the electrode intervals.

The porous carbon electrode 1 is placed in a DC or AC electric field, and the power supply electrodes 4, 4 ′ and the power supply electrode terminals 11, which are provided at both ends, have a plate shape, an expanded mesh shape, a perforated plate shape, or the like. , 11 ′ between the fixed and fixed-bed type three-dimensional electrodes (polarized electrode) in which the porous carbon electrode 1 is polarized and an anode and a cathode are formed at one end and the other end of the electrode by polarization, respectively. A porous carbon electrode electrolytic cell (fixed bed type three-dimensional electrode electrolytic cell) EC accommodating the porous carbon electrode 1 can be used. In addition, one electrode functions alone as an anode and the other as a cathode. Porous carbon electrode (fixed bed type three-dimensional electrode)
The porous carbon electrode electrolytic cell (fixed bed type three-dimensional electrode electrolytic cell) EC can be provided by disposing the electrodes 1 so as not to be alternately short-circuited and electrically connecting the anodes and the cathodes in parallel.

The materials of the power supply electrodes 4 and 4 'are as follows.
For example, carbon graphite material (carbon fiber, carbon cloth, graphite, etc.), glassy carbon, carbon composite material (such as carbon mixed with powdered metal and sintered), and dimensionally stable electrode (platinum group oxide coated titanium material) ), Platinum-coated titanium materials, platinum, copper, hastelloy, nickel materials, stainless steel materials, iron materials and the like are preferably used.

In particular, when treating the water to be treated while generating oxygen gas from the anode, the porous carbon electrode (fixed bed type three-dimensional electrode) 1 is oxidized by oxygen gas and easily dissolved as carbon dioxide gas. . To prevent this, the porous carbon electrode (fixed bed type three-dimensional electrode) 1 is coated with a platinum group metal oxide such as iridium oxide or ruthenium oxide or platinum on a base material such as titanium on the side of positive polarization. It is desired that the porous or reticulated material used as the auxiliary electrodes 2, 2 'be placed in contact so that oxygen evolution occurs primarily on the material.

The electrolytic cell E through which water to be treated flows.
If there is a gap in C that allows the liquid to flow without contacting the porous carbon electrode material, the treatment efficiency of the water to be treated is reduced. Therefore, the fixed-bed type three-dimensional electrode (porous carbon electrode) 1 and the like are provided in the electrolytic cell EC. It is important to arrange so that the flow of the water to be treated does not short-pass. Therefore, by covering the peripheral part and the side part of the porous carbon electrode with one gasket 3,
This leak flow can be prevented. Next, an example of assembling such an electrolytic cell will be described. That is, a fixed bed in which the porous carbon electrode material and the metal auxiliary electrode are previously incorporated in the gasket 3 is created. Since the gasket 3 is made of a resilient material such as rubber, the gasket 3 is made slightly smaller than the actual size of the porous carbon electrode 1 or the metal auxiliary electrodes 2 and 2 ', and is fitted while being stretched. It is preferable in terms of adhesion. Further, it is preferable that the gasket 3 on the side surface of the porous carbon electrode 1 be provided with a projection having an outer diameter slightly larger than the inner diameter of the container for accommodating the fixed-bed type three-dimensional electrode (porous carbon electrode) 1. Spreading due to the water pressure at the time can prevent leakage from here. The metal auxiliary electrodes 2 and 2 ′ may be inserted together with the porous carbon electrode 1 or may be provided on the porous carbon electrode 1.

There is also a method of filling the gap between the porous carbon electrode 1 and the cylindrical body 6 which is a part of the container of the electrolytic cell EC with a resin in order to prevent the leak. A thermosetting resin or a silicone sealant is used for such a resin. Alternatively, the electrode plate may be packed in a heat-shrinkable tube and heat-treated. However, there is a disadvantage that once hardened with resin, it cannot be easily decomposed.

It is also possible to bond the auxiliary electrode and the porous carbon electrode with a conductive resin, which is effective for suppressing the collapse of the porous carbon electrode due to anodic oxidation. Alternatively, platinum or the like may be plated directly on the porous carbon electrode. Further, these electrolytic cells EC have a problem that clogging is liable to occur due to foreign matter in the water to be treated and carbon fine powder generated by anodic oxidation. Therefore, by using a porous carbon electrode having a plurality of non-penetrating holes on the inlet side of tap water (tap water) as water to be treated for the porous carbon electrode material, clogging by foreign substances and carbon fine particles is significantly suppressed. Is done. The depth of the hole is preferably 1/4 to 3/4 of the thickness of the porous carbonaceous electrode, and the hole diameter is preferably 0.5 to 4.0 mm. The area of the hole portion is preferably 5 to 25% of the porous carbon electrode. Further, the flow rate of the water to be supplied to the electrolytic cell EC may be defined so that the water to be treated can efficiently contact the surface of the electrode or the like.

This electrolytic cell EC is installed at the subsequent stage of an activated carbon treatment tank AC (filtration treatment tank containing activated carbon) as a means for removing chlorine from the water to be treated, thereby forming a water purification apparatus 100A. Bacteria that have propagated inside can be adsorbed and sterilized on the porous carbon electrode plate. Specifically, it can be installed as shown in FIG.

FIG. 3 is a schematic diagram showing a water purification apparatus 100 as a water treatment apparatus according to the present invention.
A circuit for applying a Joule heat generation voltage to the porous carbon electrode of the electrolytic cell EC of A is installed to produce a water purification device 100 as shown in FIG. It was supplied from the discharge port after passing through the carbon electrode electrolytic cell EC. The electrolytic cell EC is heated to 90 ° C. for 10 minutes every 12 hours by the Joule heat generated by this heating means, and during heating and after heating for about 50 hours.
It is washed with 0 ml of treated water (purified water) and drained from a valve V2 that constitutes a part of a three-way valve, for example, a drainage system provided on the outlet side of the electrolytic cell. When the temperature was 50 ° C. or higher, the application of the electrolytic voltage was automatically stopped. Under these operating conditions, with water intake stopped for 120 hours (however, during this period, 90 ° C.
After repeating the washing for 10 minutes), the valve V3 was opened, and 100 ml of water was collected from the outlet of the electrolytic cell, and the viable cell count was measured. As a comparative example, a comparison was made with that shown in the schematic diagram of FIG. 3 without heat treatment. Table 1 shows the results.

[0037]

[Table 1]

As described above, even when the water purification apparatus 100 of the present invention does not use raw water as treated water for a long time, a predetermined voltage is applied to the porous carbon electrode to generate Joule heat. It can be seen that the electrode can be regenerated in the inside, and that the growth of bacteria in the electrolytic cell and the pipe at the outlet can be effectively suppressed.

By performing the heat treatment in this manner, the regenerating effect of the porous carbon electrode is remarkably good, and at the same time, it has a great effect on cleaning of dead bacteria and foreign substances. Therefore, in the present invention, the user can always use the purified water without worry. The porous carbon electrode 1 of the electrolytic cell in the water purification apparatus is automatically controlled so that the porous carbon electrode 1 of the electrolytic cell in the water purification apparatus is maintained in a regenerating state in which a normal function can be exerted at any time so that sterilized water is supplied. Further, it is possible to detect when the life of the porous carbon electrode has expired.

Hereinafter, the structure will be described in more detail.

In FIGS. 1 and 2, raw water such as tap water or well water is introduced from a raw water supply source through an inlet 15 provided at a lower portion of the electrolytic cell EC. The water supply pipe 122 is provided with a water supply valve 143 using an electromagnetic switching valve for restricting introduction of raw water. In addition, a drain pipe 154 is provided in the middle of the water pipe 122 at the outlet side of the water supply valve 143, and a drain pipe 154 is provided.
4 is also provided with a drain valve 147 using an electromagnetic switching valve. Therefore, the pipe is connected to the water supply pipe 1 by opening and closing control of the valve.
22 or the drain pipe 154, and when necessary, the raw water stored in the electrolytic cell EC can be drained from the drain pipe 154. When draining, naturally the water supply valve 143
Is closed and the supply of raw water is stopped.

More specifically, a drain pipe 154 branches from a conduit between the outlet side of the water supply valve 143 and the inlet 15 of the electrolytic cell EC, and the check pipe 145, the aspirator 146, And a drain valve 147 is provided. The aspirator 146 is a device that generates a negative pressure by a water flow of a fluid flowing through the pipeline and uses the generated negative pressure to suck air or gas.

On the inlet side of the water supply valve 143 of the water supply pipe 122, a bypass pipe 148 is provided in a branched manner.
This bypass pipe 148 is connected to and communicates with the aspirator 146 described above. Therefore, the raw water from the supply source is introduced from the bypass pipe 148 to the aspirator 146 both when the water supply valve 143 is open and when it is closed. However, when the drain valve 147 is closed, the aspirator 1
The flow of raw water to 46 will be stagnant.

From the outlet 16 of the porous carbon electrode electrolytic cell EC, the purified water pipe 1 through which purified water passes when used as drinking water or the like.
A water injection cock (not shown) that is opened and closed by a user is provided at the end of the water purification pipe 185.

A branch pipe 185B branches off from the main pipe 185A on the way of the water purification pipe 185, and a water check valve 186 is provided on the main pipe 185A side to prevent a backflow of the purified water once discharged from the electrolytic cell EC. An outside air introduction valve 187 for introducing outside air into the electrolytic cell EC is provided on the branch pipe 185B side.
The water check valve 186 and the outside air introduction valve 187 are formed as diaphragm-shaped valves, and one of the water check valves 186 is closed and the other outside air introduction valve 187 is closed by a negative pressure acting in the water purification pipe 185. Is to open.

However, in the embodiment, the water check valve 186 is used.
The outside air introduction valve 187 has a diaphragm shape made of an elastic material as shown in the figure, and an example in which the elastic deformation is used for opening and closing the valve has been described. Instead of these two valves 186 and 187,
A three-way valve using an electromagnetic valve may be disposed at the branch of the water purification pipe 185.

Further, a plurality of laminated porous carbon electrodes 1
The above-mentioned power supply electrodes 4 and 4 ′ in the form of a donut-shaped disk, which is a pair of the positive and negative electrodes, are joined to the upper and lower end surfaces in the axial direction. The power supply electrodes 4 and 4 ′ are used for sterilizing the porous carbon electrode 1 by polarizing the porous carbon electrode 1.
It is also common as a power supply electrode used for the reproduction of.
For example, an electrode terminal 11 ′ extends from the upper power supply electrode 4 as an anode, and an electrode terminal 11 extends from the lower power supply electrode 4 as a cathode to the outside of the electrolytic cell EC, and is connected to the power supply circuit 30. I have.

The adjacent porous carbon electrodes are connected by switches S1 to S6 to S1 to S9 to connect the power supply electrodes 4, 4 ', the heating / regeneration power supply circuit 30 and the sterilization polarization power supply. A switch for switching S10 and S20 is provided between them. When the porous carbon electrode 1 is used for sterilization polarization, S10 and S20 are switched as shown in FIGS. 1 and 2, and S1 to S6 to S1 to S9. Are open as shown in FIG. However, the switches S10 and S20
Is switched to heating regeneration, S1 to S6 or S
The switches 1 to S9 are closed. The operation of each of these switches is performed without error by a solenoid switch.

The power supply circuit 30 can be either AC or DC, but is a circuit having a DC power supply 31 in the embodiment. That is, when a required voltage is applied between the power supply electrodes 4 and 4 ', the porous carbon electrode is heated as an electric resistor, and the temperature rises to generate Joule heat. By this Joule heat, substances such as foreign substances adsorbed on the porous carbon electrode 1 are desorbed.

The power supply circuit 30 includes a DC power supply 31, equipped with fixed resistors R ₁ of the circuit, the porous multiple laminates of carbon electrodes 1 1, each switch S1~ between the electrodes as shown in FIG. 2
S6 or from the closed state of the S1~S9 is one electric resistor, it is possible to always detect the value of the electrical resistance R _2. The detected electric resistance R ₂ of the porous carbon electrode is sent to the control device 40. However, instead of the electric resistance R ₂ of the porous carbon electrode may detect the fixed resistors R ₁ of the circuit which is provided in series with the power supply circuit 30.

The device of the present invention includes a control device 40 such as a microcomputer shown in the block diagram of FIG. 4, and can automatically control each device constituting the device. The control device 40 includes a central processing unit (CPU) 41,
It includes a memory 42 storing a control program, an I / O port 43 for inputting and outputting to an external device to be controlled, and the like. Further, a timer circuit 47 linked to the control device 40 is provided, and a time-up signal for each process is transmitted to the control device 40 in each series of control processes. In addition, the detection signal sent to the control device 40 includes the electric resistance R ₂ of the porous carbon electrode 1 described above,
There is a signal from the thermistor 170 for detecting the heating temperature of the porous carbon electrode 1 shown in FIG.

The control device 40 sends a control signal based on the time-up signal of the timer circuit 47 to the water supply valve 143,
It is sent as an operation signal to devices such as the drain valve 147 and the power supply circuit 30.

Next, the operation of the method for regenerating a porous carbon electrode using the apparatus having the above configuration will be described with reference to the block diagram of the control device shown in FIG. 4, the flowcharts shown in FIGS. 5, 6, and the graphs shown in FIGS. Will be explained.

The operation of the apparatus is broadly controlled by repeating the normal use step (1) and the regeneration step (2) at arbitrary intervals. That is, the normal use process (1)
What is meant by the so-called porous carbon electrode 1 is when the raw water is passed through the apparatus while purifying purified water for the purpose of using drinking water or the like, or when the flow of raw water is repeatedly stopped when the use is stopped. It refers to the sterilization voltage application period. On the other hand, the regeneration step (2) is a step in which the supply of raw water is stopped at the stage where the normal use step (1) is completed, the raw water is drained from the electrolytic cell EC, and the bacteria adsorbed on the porous carbon electrode are discharged. This is a step of regenerating the porous carbon electrode 1 having a reduced sterilization ability by removing foreign substances such as the above.

In the flowchart of FIG. 5, first, in the normal use process (1), the control device 40 is started by starting the device.
The drain valve 147 is turned off and closed by the control signal from, and the water supply valve 143 is opened by the on operation, and tap water as raw water is introduced from the water supply pipe 122 into the electrolytic cell EC. Raw water enters the porous porous carbon electrode in the electrolytic cell EC from the inlet 15 and is introduced into the electrolytic cell EC until it is almost full (step S ₁ ).

The introduced raw water permeates into the porous carbon electrode and is sterilized by receiving a polarization voltage from a sterilization polarization voltage power supply circuit. At the same time, by contact with the porous carbon electrode, dissolved substances in raw water, for example, trace organic chlorine compounds, trace organic compounds, musty odor, and the like are also adsorbed on the electrode surface. The purified water passed through the water purification pipe 185 is used as drinking water.

Here, the flow of the raw water is generated in the electrolytic cell EC when using the intake water, but the flow of the raw water naturally stagnates when the water tap is closed or when the water is not used for a long time and short time. . In this way, the device repeats the flow of water and the stoppage of water, during which it is a daily use period in which the electrolytic sterilization function is performed. This is set as normal “electrolytic sterilization”, and is set based on past data and experience values as a water passage time or a water passage amount. As an example, the electrolytic sterilization period can be set in between the water passage time T _1, the water passage time T ₁ are stored in the memory 42 in advance controller 40 as an electrolytic sterilization period.

For example, foreign substances such as dead bodies of sterilization accumulate in the pores of the porous carbon electrode, making it difficult for water to pass through, thereby increasing the pressure loss. Pressure loss is 130, the initial pressure loss
Percent when the above, the time T ₁ must be regenerated by eliminating the clogging of the electrode, FIG. 1, the diameter 39.5 in inner diameter 40 mm, height 75mm container of FIG. 2
mm thickness Rohm time T ₁ is a porous carbon electrode of 10mm in an electrolytic cell constituted by five is considered appropriate to define the 12 hours. However, water passing time T ₁ can be timely determined based not necessarily limited thereto.

The timer circuit 47 counts the water passage time t ₁ , which is an electrolytic sterilization period (steps S 2 a and S 2 b), and when the time is up, the signal is input from the timer circuit 47 to the control device 40. At the same time, a warning display indicating the transition to the drainage process may be activated. The comparison unit 44 in the CPU41 compared to the water passage time T ₁ of the settings stored in the time-up signal and the memory 42 thereof to exit the electrolytic sterilization period if I match or to start playback step (2) Assuming that it is time, a command signal is sent from the I / O port 43 to devices such as the water supply valve 143 and the drain valve 147 to be controlled in order to start regeneration.

When the regeneration start command signal is issued, the drainage process is started, and in synchronization with this, the heating / regeneration power supply circuit voltage is applied between the power supply electrode 4 'and the power supply electrode 4 (step S6). .

In the regeneration step, the power supply electrodes 4 and 4 '
The voltage applied therebetween is the voltage of the heating / regeneration power supply circuit, and is simply referred to as voltage.

As the first stage of the regeneration step (2), first, in the "drainage step", an operation signal from the control device 40 displays a warning indicating that the set water passage time has been exceeded (step S3), and a water supply valve. 143 is closed (step 4), and the introduction of raw water into the electrolytic cell EC is stopped. In synchronization with this, the drain valve 147 is opened (Step S5), and all the raw water stored in the entire area of the electrolytic cell EC is discharged and discharged from the drain pipe 144. In this drainage process, the aspirator 1
The raw water flowing through the feed pipe 46 passes through the bypass pipe 148
There is no problem because the water flows back to the inlet side of 43, but is pushed back by the water pressure on the raw water supply source side.

During the drainage, the raw water in the electrolytic cell EC passes through the aspirator 146, and at the time of this passage, the drainage flow pressure is generated, and the pressure in the electrolytic cell EC is reduced by suction. Raw water stored in the electrolytic cell EC by suction and reduced pressure, and even raw water adhering to the porous carbon electrode 1 among them can be efficiently pulled and discharged.

The pressure inside the electrolytic cell EC is reduced to a negative pressure by reducing the pressure by suction of the aspirator 146. In the water purification pipe 185, the main pipe 185
The water check valve 186 on the A side is closed by the negative pressure on the upstream side, and stops the purified water on the main pipe 185A from flowing back into the electrolytic cell EC. Further, on the branch pipe 185B side, the outside air introduction valve 187 opens due to the negative pressure, and the outside air passes through the electrolytic cell EC. The suction effect by the aspirator 146 is enhanced by this air flow, and the drainage in the electrolytic cell EC is efficiently performed.

Further, in the drainage process, at the same time as the start of drainage,
A predetermined voltage is applied between the power supply electrodes 4 'and 4 (step S6). Figure 8 shows the characteristic illustrating the correlation between the detection voltage and the time by the porous change in the electrical resistance R ₂ of the carbon electrode 1 in the power supply circuit 30.

As shown in FIG. 8, the electric resistance R ₂ of the porous carbon electrode changes with the progress of drainage. By detecting this, the voltage change of the porous carbon electrode 1 over time can be obtained. The voltage change rate per unit time is set to δ1, and when the voltage change rate δ1 reaches a preset voltage change rate δa, this is regarded as the end of the drainage process.
That is, the set voltage change rate δa in the drainage process is stored in the memory 42 of the control device 40. As the drainage progresses, the voltage change rate δ1 can be calculated every moment by the calculation unit 45 of the CPU 41. Detected voltage change rate δ ₁
Reaches a set voltage change rate δa, this signal is sent from the control unit 46 and the I / O port 43 to the power supply circuit 30,
The drain valve 147 is turned off to close the drain pipe 154 (step S8), and the voltage applied between the power supply electrode 4 'and the power supply electrode 4 is adjusted, and the process proceeds to the next "desorption step".

In the reproducing method of the embodiment, the control for obtaining the set change rate according to the present invention by the voltage change rate δa is used. However, the set resistance change rate based on the change in the electric resistance R ₂ of the porous carbon electrode is obtained. Of course, control may be used.

Various detection means can be considered to detect whether or not the drainage of the raw water in the electrolytic cell EC has been completed. For example, since the capacity of the electrolytic cell EC is fixed, the storage amount of raw water is always constant, and it is easy to know how long it takes to discharge all the storage amount. The discharge time can be set in advance and counted by the timer circuit 47.

In the desorption step, the porous carbon electrode 1 is heated as an electric resistor by applying a high voltage between the power supply electrodes 4 ′ and 4, and the temperature of the porous carbon electrode 1 rises to generate Joule heat. Occur. The substance adsorbed on the porous carbon electrode is desorbed by the Joule heat (step S9). In the desorption step, the power-feeding electrode 4 ', set in advance a voltage application time to between 4 (T _2), the energizing time (t ₂₎
Is reached (step S10), it is determined that the desorption process has been completed. On the other hand, porous and made temperature detection of the carbon electrode 1, the predetermined time (T ₂₎ has elapsed before the detected temperature C has detected this when it exceeds a predetermined temperature C ₁ by the thermistor 170 in conjunction step 10 Then, the voltage application between the power supply electrode 4 'and the power supply 4 is turned off (steps 11a and 11b). That is, assuming that an arbitrary temperature differential value is ΔC, when the temperature is equal to or less than (C ₁ −ΔC), the control for turning on the voltage application to both electrodes 4 ′ and 4 is repeated until a predetermined time (T ₂ ) elapses. Do. As described above, if the porous carbon electrode 1 is heated to a predetermined temperature or higher while the desorption voltage is being applied, the application of the voltage is stopped to prevent heating and avoid damage to the porous carbon electrode. be able to. At the same time, in order to prevent incomplete desorption due to no application of the desorption voltage for a predetermined time, once the voltage application is stopped, the desorption voltage is again applied.

When the termination of the desorption step is determined, an operation signal is sent to the drain valve 147 while the application of a high voltage between the power supply electrode 4 ′ and the second power supply electrode 4 is continued, and It is opened by the operation to open the drain pipe 154. In the desorption step, since the porous carbon electrode 1 is heated at a high voltage, the desorbed adsorbed components and generated gas are removed from the electrode tank EC.
It is necessary to discharge from inside to outside, and this is called "exhaust process"
(Step S12).

In the exhaust process in the flowchart of FIG. 6, the water supply valve 143 of the water supply pipe 122 is kept closed by the OFF signal, and the drain valve 147 is opened to open the drain pipe 15.
Release 4. That is, the raw water from the raw water supply passes through the aspirator 146 through the bypass pipe 148. When raw water passes through the aspirator 146, a suction action occurs here. As a result, the inside of the electrolytic cell EC is made negative pressure over the entire interior thereof, and an air flow is generated in the outlet 16 and the water purification pipe 185 by the negative pressure. By receiving the negative pressure, the water check valve 186 on the water purification pipe 185 side closes and the outside air introduction valve 187 opens,
External air is introduced into the electrolytic cell EC including the outlet 16, and the electrolytic cell EC is sucked by the aspirator 146.
The desorbed adsorbed components and generated gas desorbed and retained inside are exhausted to the outside from a drain pipe 154 also serving as exhaust. Also, in the evacuation process, the voltage application time between the power supply electrodes 4 'and 4 is set in advance, and when the energization time reaches this (step S13a), this signal indicates the end of the evacuation process. Is sent to the power supply circuit 30 from the control unit 46 and the I / O port 43. On the other hand, also in step S13a, the temperature of the porous carbon electrode 1 is detected by the thermistor 170 as in step 10 (step S1).
3b), when the detected temperature C is the case exceeds a predetermined temperature C ₁ turns off the voltage application between the electrodes (step S13c), and ΔC any temperature differential value (C ₁ -
When the temperature is equal to or lower than ΔC), the control to turn on is repeated,
The control time t ₃ is repeated until a predetermined time (T ₃ ) elapses, thereby achieving sufficient exhaustion and prevention of damage due to abnormal heating of the adsorbent. On the other hand, when the still detected temperature C has not reached the predetermined temperature C ₁ to apply a voltage between the electrodes (step S13d).

Further, after judging the end of the evacuation step, the voltage applied between the first and second power supply electrodes is switched to a weak voltage (step S14). This is because a high voltage became unnecessary because the regeneration step was completed, and on the other hand, it is possible to detect a life determination of a porous carbon electrode described later. As shown in the voltage characteristics diagram of FIG. 7, this time the porous carbon electrode voltage reaches the set value V _s, the life of the porous carbon electrode 1 is determined to be the limit is made (step S15, S16) . This utilizes the property that the electrical conductivity decreases due to the deterioration of the porous carbon electrode and the electrical resistance increases.

[0073] Further, in step S15, if the voltage of the porous carbon electrode does not reach the set value V _s, the step S
7, it is determined whether or not the resistance or voltage change rate δ2 of the porous carbon electrode due to the electrical resistance change is equal to or less than the set change rate δb (step S17a). It is determined that the voltage change rate of the high-quality carbon electrode is reached, and all the regeneration steps are ended (step S17b).
On the other hand, when δ2 is equal to or larger than the set change rate δb, it is determined that the desorption of the porous carbon electrode is incomplete, and the desorption process is started again.

As is clear from the above, the regeneration step (2)
The cycle consists of the steps of “draining step”, “desorption step” and “exhaust step”. In each step, the completion of the step is independently determined (in the drainage step, step S7, degassing step). In the process, steps S10 and S11
a, In the exhaust process, steps S13a, S13b,
In S15 and S17a), when it is determined that the determination result is incomplete, the cycle is repeated until the determination is completed. Furthermore,
In detecting the voltage change rate of the porous carbon electrode at the end of the evacuation step, the desorption state and the life of the porous carbon electrode are also determined. The replacement of high quality carbon electrodes is to be performed.

As described above, in this embodiment, not only the interval between the normal use process and the regeneration process, but also the intervals of the drainage process, the desorption process, and the exhaust process constituting the regeneration process are set by an arbitrary set time or the like. Will be performed.

As a result, a more accurate means for regenerating a porous carbon electrode having a reduced sterilization ability can be executed at an early stage, and the following effects are exhibited.

That is, first, the life of the porous carbon electrode is improved, and second, the porous carbon electrode is cleaned by passing through the stepwise processes of drainage, desorption, and exhaustion, and the contaminants (carcass of bacteria) are removed. Performance degradation due to clogging or the like due to accumulation of water or residual chlorine-based foreign matter, etc.) is prevented. Third, in each of the regeneration steps, bacteria can be further sterilized in the porous carbon electrode by applying a voltage directly to the porous carbon electrode.
The rapid heating prevents heat losses and thus saves energy. Fourth, by optimizing the interval between each mode (water passing, exhausting, desorbing, exhausting), the number of layers of porous carbon electrodes to save energy by reducing heat loss in the exhausting process and to maintain the same sterilization ability Can be reduced.

[0078]

According to the method for regenerating a porous carbon electrode of a water purification and sterilization apparatus according to the present invention, the regeneration step is further drained at an interval of one cycle consisting of a normal use step and a regeneration step. Since the control is performed by subdividing the process into the process, the desorption process, and the exhaust process, more accurate control is performed earlier in order to regenerate the porous carbon electrode having reduced sterilization ability. For this reason, first, the life of the porous carbon electrode is improved, and second, the porous carbon electrode is cleaned by going through each step of draining, desorbing, and exhausting, and contaminants (remaining chlorine-based foreign matter) are removed. , Accumulation of dead bacteria, etc.), and performance degradation due to clogging or the like is prevented. Third, in each regeneration step, the sterilization effect of bacteria in the porous carbon electrode is further improved by directly applying a voltage for heating and regeneration to the porous carbon electrode, and rapid heating prevents heat loss. This will save energy.

Further, according to the present invention, either the voltage change rate or the electric resistance change rate of the porous carbon electrode corresponding to the change of the electric resistance value of the porous carbon electrode which is the electric resistor. By detecting this set change rate and performing comparison control with the constantly detected change rate, when the set change rate is exceeded, it is time to accurately replace the porous carbon electrode, such as when it is time to replace the porous carbon electrode. There is an advantage that the life of the high quality carbon electrode can be determined.

Further, in the third aspect, by optimizing the interval between each mode (water supply, exhaust, desorption, exhaust), energy saving by reducing heat loss in the exhaust process and maintaining the same sterilizing ability are maintained. Therefore, the size can be reduced by reducing the number of stacked porous carbon electrodes.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a water purification apparatus to which a method for regenerating a porous carbon electrode according to an embodiment of the present invention is applied.

FIG. 2 is a schematic cross-sectional view of a water purification apparatus to which a method for regenerating a porous carbon electrode according to another embodiment of the present invention is applied.

FIG. 3 is a configuration diagram of a water purification apparatus in which a filter tank and an activated carbon treatment tank are connected upstream of an electrolytic tank.

FIG. 4 is a block diagram showing a control device of the water purification apparatus to which the method of the present invention is applied.

FIG. 5 is a flowchart of a first operation of the water purification apparatus to which the regeneration method of the present invention is applied.

FIG. 6 is a flowchart of a second operation of the water purification apparatus to which the regeneration method of the present invention is applied.

FIG. 7 is a voltage characteristic diagram showing a correlation between a detection voltage that changes based on the electric resistance of a porous carbon electrode and each step in one cycle.

FIG. 8 is a graph showing a change in electric resistance of a porous carbon electrode in each step.

[Explanation of symbols]

 Reference Signs List 1 fixed bed type three-dimensional electrode (porous carbon electrode) 2 auxiliary electrode 2 'auxiliary electrode 3 gasket 4 power supply electrode (for external power supply) 4' power supply electrode (for external power supply) 5 inner cylinder (tube) 6) Outer cylinder (cylindrical body) 9, 9 ', 9 "Spacer 10 Cover 11 Electrode terminal 11' Electrode terminal 15 Inlet 16 Outlet 18 Bottom plate 30 Power supply circuit 40 Controller 47 Timer circuit 122 Water supply pipe 143 Water supply valve 145 Check valve 146 Aspirator 147 Drain valve 148 Bypass pipe 154 Drain pipe 170 Thermistor 185 Water purification pipe 185A Main pipe 185B Branch pipe 186 Water check valve 187 Outside air introduction valve

Claims (3)

[Claims] 1. A raw water introduced into a porous carbon electrode electrolytic cell by a water supply pipe is brought into contact with a porous carbon electrode to which a sterilizing polarization voltage is applied to purify and sterilize the raw water, and the purified water is supplied to an outlet side of the electrolytic cell. Water purification sterilization that repeats a cycle consisting of a normal use step of taking out and using the provided water purification pipe and a regeneration step of draining raw water stored in the electrolytic tank from a drain pipe and regenerating the sterilization efficiency of the porous carbon electrode. A method for regenerating a porous carbon electrode of an apparatus, wherein the regeneration step comprises closing a water supply valve and opening a drain valve of a raw water by a time-up signal indicating that the normal use step has been completed, thereby obtaining raw water from a raw water supply source. Is passed through an aspirator provided in the drainage pipe to drain the raw water stored in the electrolytic cell by suction and pressure reduction. A drainage step of applying a voltage of a heating / regenerating power supply circuit to the poles and draining until it is detected that a rate of change δ1 of resistance or voltage due to a change in electric resistance of the porous carbon electrode has reached a set rate of change δa; In the drainage step, the water supply valve is closed and the drainage valve is closed with a control signal indicating that the set change rate δa has been reached, and the applied voltage is controlled to heat the porous carbon electrode to a predetermined temperature and adhere. A desorption step of desorbing the adsorbed component, and when the rate of change δ2 of resistance or voltage due to a change in electric resistance of the porous carbon electrode reaches the set rate of change δb in the desorption step, this is detected and controlled. The signal is applied to the porous carbon electrode to reduce the applied voltage to a predetermined weak voltage to continue heating, and the operation signal indicating that the set change rate δb has been reached, the water supply valve is closed and the drain valve is closed. To In addition, an exhaust step of introducing raw water from the raw water supply source to the aspirator through the bypass pipe to suction and reduce the pressure in the electrolytic cell, and discharging the desorbed adsorption component and generated gas to the outside from the drain pipe, A method for regenerating a porous carbon electrode in a water purification and sterilization apparatus, comprising: 2. The set change rate δ in the draining step.
a, or when the set change rate δb is determined in the desorption step, when the detection voltage of the porous carbon electrode exceeds the set voltage Vs, this is determined to be the time to replace the porous carbon electrode. The method for regenerating a porous carbon electrode of the water purification apparatus according to claim 1. 3. A preset time count is used to detect the completion of the drainage step, desorption step, and exhaust step in the water purification and sterilization apparatus, and to perform a regeneration step consisting of drainage, desorption, and exhaustion for an arbitrary time. 2. The method according to claim 1, wherein the step is performed at intervals.
4. The method for regenerating a porous carbon electrode of the water purification apparatus according to item 1.