JPH06312179A - Purified water sterilizing device and use thereof - Google Patents

Abstract

PURPOSE:To enhance the treatment capacity of raw water while ensuring the safety as drinking water and to inexpensively purify the raw water in an energy- saving manner by preventing the overheating of an adsorbing part by a temp. detection means and an oxygen detection means when a usual time and a regeneration time are repeated at a definite interval and preferentially achieving the changeover to a sterilizing mode. CONSTITUTION:When the temp. of an adsorbing part 20 detected by a temp. detection means 18 exceeds an upper limit value during a period when a usual time and a regeneration time are repeated at a definite interval, a signal is sent to a changeover means 29 from a control unit 30 in order to return the temp. of the adsorbing part 20 to a set region to control a power supply circuit 28. When the temp. of the adsorbing part 20 falls below a lower limit value, the power supply circuit 28 is changed over to a sterilizing mode and AC voltage is allowed to flow to the adsorbing part 20 to generate heat in the adsorbing part 20 to raise the temp. of the adsorbing part 20. Since the concn. of dissolved oxygen in the treated water passing through the adsorbing part 20 falls below an objective value when a detection signal is sent out from an oxygen detection means 19, the sterilizing mode is taken in preference to all of processes.

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 and sterilizing raw water such as tap water or ground water and supplying it as drinking water for general households and business and a method of using the same.

[0002]

2. Description of the Related Art Recent technical trends relating to sterilization of raw water in this type of water purification apparatus include an apparatus for sterilizing microorganisms such as bacteria by using a hollow fiber membrane module (commercially available product) to suppress breeding and to control bacteria. A device for sterilizing raw water by electrolysis and a device for sterilizing with an appropriate amount of chlorine are known.

Generally, in the case of a water purification device as a water treatment device, hypochlorous acid (C) contained in raw water such as tap water or ground water is used.
lO ^-) and residual chlorine components such as organic chlorine compounds, musty odor, trihalomethane, or general bacteria and the dye is adsorbed and removed by passing through an adsorbent or sterilizer. With the use over time, algae, bacteria, and microorganisms propagate due to the adsorbed substances adsorbed on the activated carbon and the wall surface of the storage tank in this manner, which increases the load on the filter and shortens the life of the device. Since the function of the adsorbent decreases depending on the adsorbed substance, the adsorbent is desorbed to regenerate the adsorbent, and various sterilization means are incorporated into the device to improve water purification efficiency and support maintenance and maintenance of the device. is doing.

[0004]

By the way, in the case of a sterilizer using a hollow fiber membrane module, the fiber membrane module is apt to be clogged with impurities in the raw water due to long-term use, and the treatment capacity is generally low. Electrolytic sterilizers have problems in terms of economy such as power consumption. Further, in the case of a sterilizer using chlorine, it is difficult to control and manage it in order to control it to a suitable chlorine concentration in consideration of safety. As described above, the conventionally known sterilization methods each have a problem to be solved.

An object of the present invention is to provide a water purification apparatus which secures safety as drinking water, enhances the treatment capacity of raw water, can save power, and is advantageous in terms of cost.

[0006]

In order to achieve this object, in the water purifying and sterilizing apparatus according to the first aspect of the present invention, an adsorbing section made of conductive activated carbon having a required shape is arranged in a water tank, and a water supply valve is provided. When purifying and sterilizing the raw water introduced into the water tank from the adsorber at the adsorption section before use, in normal times, the raw water passes through or stops at the adsorption section by repeated use and non-use. In a device that drains raw water in the water tank and in the adsorption section from the drain valve, a pouring tube inserted in the center of the adsorption section as a conductive tube section with a large number of water passage holes made of a conductive material, and adsorption during regeneration A pair of first and second electrodes to which a voltage is applied as a sterilization mode for sterilizing the bacteria in the raw water by sterilizing the parts, and the conductive pipe part of the spout pipe, which is normally provided in the raw water. As a bacteriostatic mode that captures and reproduces Pressure is applied between either the first electrode or the second electrode, a third electrode, a timer circuit that counts each execution time during normal and repetitive intervals, and a voltage in sterilization mode or Switching means for switching to the bacteriostatic mode, a power supply circuit for applying a voltage corresponding to the sterilization mode or the bacteriostatic mode when switched by the switching means, and temperature detection provided inside the adsorption part for detecting the temperature of the adsorption part Means, an oxygen detection means provided inside the adsorption part or at the outlet end of the adsorption part on the downstream side of the raw water flow of the adsorption part, for detecting when the dissolved oxygen concentration in the treated water passing through the adsorption part falls below a target value, and a timer. Based on the time-up signal from the circuit, an operation signal is sent to the water supply valve, drain valve, and switching means, and the temperature of the adsorption unit is controlled by the temperature detection means to indicate the region between the upper and lower limit values. A control signal for sending a switching signal for the temperature-based priority mode to the switching means when a detection signal indicating that the oxygen-based priority mode has been sent, and a switching signal for sending the switching signal for the oxygen-based priority mode to the switching means when a detection signal is sent from the oxygen detection means. It has a configuration including.

The method of using the water purification apparatus of claim 2 is that when normal time and regeneration are repeated at regular intervals,
Normally, a sterilization mode process in which a weak voltage is applied between one of the first electrode or the second electrode and the third electrode by the power supply circuit by switching the switching means by a control signal from the control device, At the time of regeneration, the water supply valve is closed to stop the introduction of raw water into the water tank and the drain valve is opened to open the water tank and the inside of the adsorption unit by the control signal from the controller based on the time-up signal indicating that the bacteriostatic mode process has been completed. Of the drainage process for discharging the raw water and the control signal from the control device based on the time-up signal indicating that the drainage process has been completed, the switching means is switched, and the power supply circuit sets the voltage at which the heat of the adsorption portion can be generated.
And a sterilization mode process applied between the electrode and the second electrode.

During the normal and regenerating intervals, the control unit switches the temperature based on the detection signal of the temperature detecting means so that the temperature of the adsorption unit falls within the set temperature range between the upper limit value and the lower limit value. The power supply circuit is controlled by a signal, and when the lower limit value is exceeded, the process of temperature-based priority mode in which the power supply circuit is switched to the sterilization mode based on this detection signal and the sterilization mode when the detection signal is sent from the oxygen detection means. The oxygen-based priority mode process that sends a mode switching signal to the switching means, which prioritizes all processes.
Can be interrupted.

In the method of use according to the third aspect, a weak DC voltage can be applied in the antibacterial mode, and an AC voltage or a DC voltage capable of generating heat in the adsorption section can be applied in the sterilization mode.

Similarly, in the case of the method of use according to claim 4,
It is also possible to control to turn off the voltage application in the bacteriostatic mode when the raw water is flowing during normal use.

[0011]

In the water purification apparatus and method of use according to claims 1 and 2, a switching signal is sent from the control device to the switching means and the electrode selected from the first, second and third electrodes. Apply voltage between them. By applying a weak voltage to the first electrode and the third electrode (or between the second electrode and the third electrode) at a normal stage, bacteria and the like in the raw water are trapped in the adsorption part to suppress the reproduction. At the stage of regeneration, when the adsorption unit is regenerated, the water supply valve is closed by the operation signal from the control device based on the time-up signal to stop the raw water supply, and the drain valve is opened to drain the raw water in the water tank. Next, a voltage is applied between the first electrode and the second electrode to heat the adsorption portion, and the bacteria and the like trapped in the adsorption portion at the normal stage are sterilized.

When the temperature of the adsorbing section exceeds the upper limit value from the temperature detecting means while repeating the normal time and the regenerating time at a constant interval, the adsorbing section is detected based on the signal from the temperature detecting means which detects this. In order to return the temperature of 1 to the set region (power saving and prevention of high temperature deterioration of the adsorption part), the control device sends a switching signal to the switching means to control the power supply circuit. When the temperature falls below the lower limit, the power supply circuit is switched to the sterilization mode based on this detection signal, and a current due to an AC voltage is passed through the adsorption section to generate heat and raise the temperature.

On the other hand, when a detection signal is sent from the oxygen detection means, this means that the dissolved oxygen concentration in the treated water that has passed through the adsorption section is below the target value (microorganisms such as aerobic bacteria consume much oxygen). Therefore, even if a normal bacteriostatic mode process is in progress or another process is in progress, it has priority over all of these processes. A mode switching signal for switching to the sterilization mode is sent from the control device to the switching means.

Further, as in the method of use according to claim 3, by applying a weak DC voltage in the normal bacteriostatic mode process, bacteria and the like in the raw water are trapped in the adsorption part and the growth is suppressed. . Bacteria and the like are trapped in the adsorption unit by utilizing the characteristic that the surface of microorganisms such as bacteria generally bears weak anions when electricity is applied to the adsorption unit by a weak DC voltage. In addition, in the sterilization mode process at the time of regeneration, by applying a voltage that is high enough to generate heat in the adsorption unit, the bacteria and the like captured in the sterilization mode process are sterilized.

Further, as in the method of use of claim 4, when raw water is flowing during normal use, from the viewpoint of deterioration of capacity due to bacteria etc. adhering to the adsorbing part, water stoppage occurs. Bacteria and the like in the raw water flow more than in the inside, and it is still less likely that it will stay in the adsorption part. For this reason, the voltage application in the bacteriostatic mode can be turned off only in the passage of water as long as the bacteria and the like are allowed. This is a control that considers power consumption. However, it is desirable to control the capture of bacteria and the like by the application of a weak voltage and the suppression of reproduction throughout the normal process of repeating water supply and water stoppage.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a water purification apparatus and a method of using the same according to the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of the purified water sterilizer of the embodiment. The apparatus has a water tank 10, and raw water such as tap water is introduced from an inlet 11 provided at the bottom of the tank through a water supply pipe 12. The water supply pipe 12 is provided with a water supply valve 13 such as a solenoid valve that restricts the introduction of raw water.
A drain valve 15 that is a solenoid valve or the like is also provided in the drain pipe 14 that is branched off from the middle. By switching the pipeline, the raw water in the water tank 10 can be drained and discarded from the drain pipe 15. Of course, the water supply valve 13 is closed during drainage.

Inside the water tank 10, there is disposed an adsorption portion 20 which is formed into a cylindrical shape by using fibrous activated carbon which is electrically conductive and has a fixed shape. Filter members 21 and 22 are fitted on the cylindrical inner and outer peripheral surfaces of the suction portion 20. Between the cylindrical adsorption unit 20 and the water tank 10, the adsorption unit 2
0 is an annular passage 16 which surrounds 0, and the above-mentioned raw water inlet 11 communicates with this outer annular passage 16. Therefore, the raw water introduced from the introduction port 11 will not pass through the outer ring passage 16
Then, it is supplied to the adsorbing portion 20 through the filter member 21 on the outer peripheral side and can come into contact therewith.

A cylindrical outlet pipe 23 is provided so as to be fitted into the filter member 22 on the inner peripheral side from the inside so as to pass through the center of the suction portion 20. A part of the spout pipe 23 is a conductive pipe portion 23A formed of stainless steel or the like, and a large number of water passage holes 24 are provided therein.
A resin pipe portion 23B is joined to the conductive pipe portion 23A in the axial direction, and the spout pipe 23 is a joint pipe of two different materials. Further, the lower portion of the conductive pipe portion 23A is closed with a bottom, and the water purified by passing through the adsorbing portion 20 can be introduced into the spout pipe 23 through the water passage hole 24 through the filter member 22 on the inner peripheral side. is there. The water purification pipe 17 is connected to the upper resin pipe portion 23B, and a water injection plug (not shown) provided at the end of the water purification pipe 17
The tubular structure composed of the adsorbing part 20 and the inner and outer peripheral filter members 21 and 22 is a donut disc-shaped first and second upper and lower end formed of a pair of Yin and Yang. It is sandwiched between the electrodes 25 and 26, and from the upper part, for example, the first electrode 25 as an anode, the terminal rod 25
a is the terminal rod 26 from the second electrode 26 which is the lower cathode.
a is led out of the water tank 10 and connected to the power supply circuit 28. In addition, the extraction pipe 2 inserted into the suction unit 20
The third conductive tube portion 23A has a third outer surface on the lower bottom portion.
The electrode 27 is attached, and the terminal rod 27a of the third electrode 27 is attached.
Also goes out of the water tank 10 and is connected to the power supply circuit 28.

The power supply circuit 28 is a circuit capable of switching between alternating current and direct current, and is simply provided with both the direct current power supply 28A and the alternating current power supply 28B as in the embodiment, and is provided in the circuit, for example. Electromagnetic changeover switch (changeover means)
Switching of applying an alternating voltage between the first electrode 25 and the second electrode 26 or applying a direct voltage between the first electrode 25 (or the second electrode 26) and the third electrode 27 by means of 29. It is possible.

As shown in the block diagram of FIG. 2, the device of the present invention is automated by including a control device 30 such as a microcomputer. The control device 30 includes a central processing unit (CPU) 31, a memory 32 storing a control program, and an I / O port 3 for inputting / outputting to / from an external device to be controlled.
3 etc. are included. In addition, a timer circuit 34 is provided to send a time-up signal for each series of control processes to the control device 30. A control signal based on the time-up signal of the timer circuit 34 is sent from the control device 30 to the water supply valve 13 and the drain valve 15 as an operation signal. Further, a changeover signal is sent from the control device 30 to the changeover switch 29 of the power supply circuit 28 by the time-up signal,
Either the DC power supply 28A or the AC power supply 28B is used as a power supply circuit, and a DC voltage or an AC voltage is applied between selected electrodes of the first to third electrodes 25 to 26.

Further, as shown in FIG. 1, in the apparatus of the present invention, a thermistor 18 as a temperature detecting means and an oxygen sensor 19 of the oxygen concentration detecting means are provided around the adsorbing portion 20 as a temperature detecting means.
Is installed. The thermistor 18 is provided in a lower region inside the adsorption unit 20 to detect the temperature of the adsorption unit 20 one by one, and the oxygen sensor 19 is provided inside the adsorption unit 20 or on the outlet side of the adsorption unit 20 at the downstream side where raw water flows. That is, that is, in the embodiment, it is arranged at the inner lower end of the spout pipe 23, and
This is detected when the dissolved oxygen concentration in the treated water that has passed through is lower than the target value. By the way, the fact that the concentration of dissolved oxygen in the treated water is low and low indicates that microorganisms such as aerobic bacteria consume much oxygen and grow and grow.

An appropriate number of dowel-shaped projections 25b and 26b are formed on the inner surfaces of the upper and lower first and second electrodes 25 and 26, respectively.
Are provided, and by making these stick out from the upper and lower end surfaces of the adsorption portion 20, the contact and electrical conductivity of the first and second electrodes 25, 26 with respect to the adsorption portion 20 are enhanced, and the positioning of the assembly is ensured.

Next, regarding the method of use and the operation of the embodiment of the water purification apparatus having the above-mentioned structure, the operation flowchart of FIG. 3, the timing chart of FIG. 4, and the characteristic diagram of the correlation between the number of bacteria in the adsorbent section and the voltage of FIG. Will be described together.

The operation of the apparatus is controlled by repeating the normal time (1) and the reproduction time (2) at regular intervals.
That is, in the normal time (1), a flow occurs in the raw water while the purified water is being poured out as drinking water, and when the use is stopped, the flow of the raw water stagnates and water passing / stopping is repeated. This is a process of trapping the bacteria and the like in the adsorbing section 20 and suppressing the reproduction thereof, and hereinafter, this is referred to as a "bacteriostatic mode" process. On the contrary,
Regeneration (2) is a process of stopping the supply of raw water at the stage when the normal time (1) is finished, draining the raw water from the water tank 10 and disinfecting the bacteria and the like adsorbed to the adsorption unit 20, Consists of this drainage process and the "sterilization mode" process.

As shown in the timing chart of FIG. 4, from time t ₁ in the normal bacteriostatic mode process to the drainage process during regeneration, the sterilization mode process is terminated and the next sterilization is performed again. The interval time is t ₄ .
When regenerating, the supply of raw water is stopped, and the water tank 10 and the adsorption unit 2
Let t _{2 be} the time of the drainage process of draining and discarding all raw water stagnating within 0, and t ₃ the time of the sterilization mode process of finishing the drainage process and starting sterilization.

In the flow chart of FIG. 3, first, in the normal time (1), the drain valve 15 is closed and the water supply valve 13 is opened by the control signal from the control device 30 when the device is started, and the tap water which is the raw water is supplied to the water supply pipe line. Enter the outer ring passage 16 from 12 once,
The water is introduced almost completely into the water tank 10 (step S ₁ ).

The introduced raw water is filtered by the filter member 2 on the outer peripheral side.
After being filtered by 1, the activated carbon of the adsorption unit 20 is contacted. By contact with the adsorption unit 20, dissolved substances in the raw water, for example, trace organic chlorine compounds, trace organic compounds, musty odor, etc. are adsorbed and removed. The purified water that has been purified is the inner filter member 2
It is filtered again at 2 and enters the outlet pipe 23 through a number of water passage holes 24. It is used for drinking water, etc. from this pouring pipe 23 through the water purification pipe 17. When the user opens the water tap at the end of the water purification pipe 17 and uses it for pouring, raw water flows in the water tank 10. On the other hand, the flow of raw water is naturally stagnant when the water tap is closed and not in use, or during long-term short-term absence.

The time period during which the passage / stopping of raw water is repeated is set based on past data and empirical values, and this period is set as the normal time (1).
In the adsorption unit 20 in the water tank 10 at the normal time (1), the changeover switch 29 switches the power supply circuit 28 to a circuit by the DC power supply 28A by a switching signal from the control device 30.
That is, by the DC power supply 28A, the upper first electrode 2
5 as the (+) electrode and the third electrode 27 of the extraction pipe 23 as the (-)
When a weak DC voltage is applied between the electrodes serving as the poles, a weak current is passed through the adsorption unit 20 (step S ₂ ). In the embodiment, the structure in which the voltage is applied between the first electrode 25 and the third electrode 27 is adopted, but a mode in which the voltage is applied between the lower second electrode plate 26 and the third electrode 27 is also possible. is there. The reason for applying a weak DC voltage to the adsorption unit 20 in the normal mode (1) as the sterilization mode process is as follows.

That is, by applying a weak direct current to the adsorbing part 20 which is a conductor, the surface of microorganisms such as bacteria generally has a weak anion, so that the adsorbing part can catch bacteria and the like. In addition, the growth of bacteria is further suppressed in the adsorbing section 20 while the raw water is stagnant due to nonuse. In particular, when the user stays away for a long period of time, raw water is likely to stay in the adsorption unit 20 and promote bacterial growth. Therefore, it is also a treatment for suppressing this. The weak DC voltage applied between the first electrode 25 and the third electrode 27 in the bacteriostatic mode process is hereinafter referred to as bacteriostatic voltage E _AC .

The normal bacteriostatic mode process in the present invention is as follows.
This is a field that is being actively researched academically as part of the water sterilization method. For example, "Iron and Steel: 1976 (199
0) No. 9 ”," A New Sterilization Method Using Ion Exchange Membrane Electrodialysis Method "(Showa Pharmaceutical University Faculty of Pharmacy Toshio Sato, Yokohama National University Faculty of Engineering Professor Haruhiko Oya) has a chemical sterilization method and physics. It is said that it is necessary to solve the problems of the sterilization method and to develop a completely new sterilization method in principle.

The basis of the bacteriostatic mode process of the present invention is based on the common theory that in the field of bacteriology, the surface of microorganisms is anionized in a weakly charged state, and therefore, according to the experiments by the inventors, for example, 5 volts. It has been confirmed that it is possible to prevent bacteria in the raw water from being captured by the adsorption unit 20 and flowing out into the pouring pipe 23 as they are, by allowing a certain amount of direct current to flow through the adsorption unit 20. Further, it is possible to sterilize the bacteria once captured by further increasing the voltage. The process for this sterilization is theoretically detailed in the article.

Now, in the normal time (1), the total amount of time due to repeated use of water flow / stoppage is set as the bacteriostatic mode process from the experience value to t.
_When set to ₁ , this set time t ₁ can be stored in the memory 32 of the control device 30 in advance. That is, in the control device 30, the timer circuit 3 measuring the set time t ₁
When the time-up signal from 4 is input (step S
₃ ), this signal is stored in the memory 32 and CP
The control unit in U31 determines and sends a command signal from the I / O port 33 to the water supply valve 13 and the drain valve 15 to be controlled in order to start the regeneration (2). The water supply valve 13 is closed by the operation signal to stop the introduction of raw water into the water tank 10, and in synchronization with this, the drain valve 15 is opened to discharge all the raw water accumulated in the entire water tank 10 from the drain pipe 14. Discard. The time of this drainage process is t ₂ (step S ₄ ).

The power supply circuit 28 is an embodiment in which the operation of the water supply valve 13 and the drainage valve 15 is not related to the operation. It is possible to use a solenoid valve for both valves to turn them on and off with a different power supply by a control signal from the control device 30. it can. As the operating voltage of both valves,
As shown in the time chart of FIG. 4, a voltage Ev that is considerably higher than the sterilization voltage E _AB in the next sterilization mode process is required.

The timer circuit 33 counts the completion of the drainage time t ₂ , the time-up signal is sent to the control device 30 (step S ₅ ), and the switching signal is sent from the control device 30 to the change-over switch 29. The AC power supply 28B of the power supply circuit 28 is closed. An AC voltage is applied between the first electrode 25 and the second electrode 26 by an AC power supply 28B. The AC voltage is higher than bacteriostatic voltage E _AC in the previous bacteriostatic mode, a sterilizing mode process bacteria or the like trapped in the suction unit 20 in bacteriostatic mode is applied as fungicidal voltage E _AB enough to sterilization by heat Start (step S ₆ ).
In the sterilization mode process, the first electrode 25 and the second electrode 26
The time during which the sterilization voltage E _AB is applied is t ₃ . As a result, an alternating current is caused to flow through the adsorbing portion 20 which is a conductor, and the amount of heat flowing out from the adsorbing portion 20 per unit time, that is, Joule heat is generated to sterilize and reduce the bacteria attached to the adsorbing portion 20. Although an AC voltage is applied in the embodiment, it is possible to use a DC voltage because bacteria are not required to be captured in the sterilization mode process. As is clear from the voltage characteristics of FIG. 5, the higher the sterilization voltage E _AB , the smaller the number of bacteria held in the adsorption unit 20.

When the application time t ₃ has passed and the sterilization process is completed (step S ₁₁ ), the process in the bacteriostatic mode at the normal time (1) is resumed until the next sterilization start interval time t ₁ .

On the other hand, while the normal time and the reproduction time as described above are repeated at a constant interval, the above-mentioned step S ₆
At the stage, for example, when the sterilization voltage E _AB is applied between the first electrode 25 and the second electrode 26 in the sterilization mode process, if the heat generation temperature of the adsorption unit 20 exceeds the upper limit value T ° C. (step S _7), it is necessary to return to the sterilizing mode of the set area the temperature of the suction unit 20. The reason for this is that the suction unit 20
If the heat generation temperature is higher than necessary, it is also disadvantageous in terms of power saving, and it has the meaning of preventing high temperature deterioration of the adsorption unit 20.

Therefore, the thermistor 18 is attached to the suction portion 20.
When it is detected that the exothermic temperature of exceeds the upper limit value T ₁ ° C, this detection signal is sent to the control device 30, the control signal is sent to the changeover switch 29, and the power supply circuit 28 is turned off by the changeover signal (step S ₈ ) Lower the temperature of the adsorption unit 20. However, the power supply circuit 28 is said to be turned off when the heat generation temperature of the adsorption part 20 exceeds the upper limit value T ₁ ° C. However, in the present invention, the adsorption part 2 is not completely turned off.
A weak voltage may be applied to the extent that Joule heat having a resistance of 0 is not generated. In this way, a sterilizing effect by an electric current other than heat generation can be expected. When the temperature is below the lower limit T ₂ ° C (step S ₉ ), the thermistor 18 that detects this
The power supply circuit 28 is switched to the sterilization mode on the basis of the signal from and the temperature of the adsorption unit 20 is raised to an appropriate temperature for generating heat.

In this way, the temperature of the adsorption section 20 is managed so as to be in the set region between the upper and lower limit values. The above is the temperature-based priority mode.

On the other hand, when the detection signal is sent from the oxygen sensor 19 (step S ₁₀ ), this is the adsorption unit 20.
It shows that the oxygen dissolved concentration C in the treated water that has passed through is less than the target value Co. At this time, even if the normal sterilization mode process is being executed or other processes are being executed, a switching signal is issued to switch the power supply circuit 28 to the sterilization mode with priority over all these processes. Is sent from the control device 30 to the changeover switch 29. This prevents microorganisms such as aerobic bacteria from consuming a large amount of oxygen to grow and grow. The above is the oxygen concentration-based priority mode.

In the method of use in the apparatus of the above-described embodiment, in the normal time (1) when the passage / stopping of raw water is repeated.
The bacteriostatic voltage E _AC was applied between the first electrode plate 25 and the third electrode plate 27 during the entire process of passing water and stopping water. As a modification of this embodiment, in the present invention, it is possible to perform control in which it is not necessary to apply the bacteriostatic voltage E _AC during the passage of water.

That is, when the raw water is flowing during normal use, from the viewpoint of bacteria and the like adhering to the adsorbing section 30 and lowering the capacity, the bacteria and the like in the raw water are more than those in the water stoppage. There is still little chance that it will stay in the adsorption unit 30 as it flows. For this reason, the voltage application in the bacteriostatic mode can be turned off only in the passage of water as long as the bacteria and the like are allowed. This is a control that considers power consumption. However, it is desirable to control the capture of bacteria and the suppression of reproduction by applying a weak DC voltage throughout the normal process of repeating water supply and water stoppage.

[0043]

As described above, according to the water purification apparatus and the method of using the same of claims 1 and 2 according to the present invention, between the three electrodes with respect to the adsorption part made of conductive activated carbon arranged in the water tank. By gradually applying from a weak voltage to a high voltage by selecting with, it is a method of sterilizing by heating the bacteria and the like trapped in the adsorption section with a weak current at the next high voltage current, so that the conventional device As described above, there is an advantage that power consumption is significantly reduced as compared with a device that directly electrolyzes raw water to sterilize bacteria and the like in the raw water. Further, it is not necessary to increase the size of the entire apparatus in order to increase the treatment capacity of raw water, and the size can be reduced.

According to the method of use of claims 2 and 3, a weak direct current voltage is applied as a bacteriostatic mode process during normal operation by repeating water flow and water stoppage to trap bacteria and the like in the raw water in the adsorption part. In addition, further growth is suppressed, and when a sterilization mode process has passed a certain time (period), bacteria attached to the adsorption unit are sterilized by applying a large AC voltage in the sterilization mode process, and this series of control is performed. It can be done efficiently at regular intervals.

In the method of using such a device,
While repeating normal time and playback at regular intervals,
The detection signals from the temperature detection means and oxygen detection means save power by preventing overheating of the adsorption part and prevent high temperature deterioration of the adsorption part, and microorganisms such as aerobic bacteria consume much oxygen to grow and grow. You can control what you do.

[Brief description of drawings]

FIG. 1 is a sectional view of a water purification sterilizer according to an embodiment of the present invention.

FIG. 2 is a block diagram of a control mode of the water purification apparatus of the embodiment.

FIG. 3 is a flowchart of operations in the water purification apparatus and the sterilization method according to the embodiment.

FIG. 4 is a time chart of a purified water sterilizing apparatus and a sterilizing method according to an embodiment.

FIG. 5 is a characteristic graph showing the correlation between the number of bacteria and the voltage in the water purification apparatus of the embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Water tank, 13 ... Water supply valve, 15 ... Drain valve, 17 ... Water purification pipe, 18 ... Thermistor (temperature detection means), 18 ... Oxygen sensor (oxygen concentration detection means), 20 ... Activated carbon adsorption part, 23
... Pour-out pipe, 23A ... Conductive pipe part, 23B ... Resin pipe part, 25
... first electrode, 26 ... second electrode, 27 ... third electrode, 28 ...
Power supply circuit, 28A ... AC power supply, 28B ... DC power supply, 29
... Changeover switch, 30 ... Control device.

Claims (4)

[Claims] 1. When the adsorbing part made of conductive activated carbon formed into a required shape is arranged in the water tank, and the raw water introduced into the water tank from the water supply valve is purified and sterilized by the adsorbing part before use,
In normal times, raw water passes through or stops water in the adsorption unit by repeating use and non-use, and when regenerating the adsorption unit, part of the water purification device that drains the raw water in the water tank and adsorption unit from the drain valve A conductive tube with a large number of water holes made of a conductive material, which is inserted in the center of the adsorption section, and a voltage as a sterilization mode that sterilizes bacteria in raw water by heating the adsorption section during regeneration. A pair of first and second electrodes to be applied, and a voltage as a bacteriostatic mode that is provided in the conductive tube part of the spout tube and normally suppresses and reproduces bacteria in raw water
A third electrode that is applied between either the electrode or the second electrode, a timer circuit that counts each execution time during normal time and regeneration that repeats at regular intervals, and the voltage is set to the sterilization mode or sterilization mode. Switching means for switching, a power supply circuit for applying a voltage corresponding to the sterilization mode or antibacterial mode when switched by the switching means, a temperature detection means provided inside the adsorption part for detecting the temperature of the adsorption part, The oxygen detection means installed inside the section or at the outlet end of the adsorption section on the downstream side of the raw water flow, to detect when the dissolved oxygen concentration in the treated water that has passed through the adsorption section falls below the target value, and the time from the timer circuit. Based on the up signal, send an operation signal to the water supply valve, drain valve and switching means,
When a detection signal is sent from the temperature detecting means that the temperature of the adsorption part is out of the range between the upper and lower limits When a switching signal of the temperature base priority mode is sent to the switching means and when a detection signal is sent from the oxygen detecting means A water purification apparatus, comprising: a control device that sends a switching signal for the oxygen-based priority mode to the switching means. 2. The method of using the water purifying apparatus according to claim 1, wherein the normal time and the regenerating time are repeated at regular intervals, wherein in normal time, the switching means is switched by a control signal from the controller.
A bactericidal mode process in which a weak voltage is applied between the first electrode or the second electrode and the third electrode by the power supply circuit, and a time-up signal indicating that the bacteriostatic mode process has ended during regeneration. Based on the control signal from the control device based on this, the drainage process of closing the water supply valve to stop the introduction of raw water into the water tank and opening the drainage valve to discharge the raw water in the water tank and the adsorption unit, and the time of the completion of the drainage process The switching means is switched by a control signal from the control device based on the up signal, and a voltage capable of generating heat in the adsorption portion is set by the power supply circuit to the first electrode and the second electrode.
During the sterilization mode process applied between the electrodes and during the normal and regeneration intervals, the detection signal of the temperature detection means is set so that the temperature of the adsorption part falls within the set temperature range between the upper and lower limits. The power supply circuit is controlled by the switching signal from the control device based on the above, and when the lower limit value is exceeded, the process of the temperature-based priority mode in which the power supply circuit is switched to the sterilization mode based on this detection signal and the detection signal from the oxygen detection means. When oxygen is sent, the process of the oxygen-based priority mode which sends a mode switching signal to the switching means to prioritize the sterilization mode over all the processes, and the method of use. 3. The method according to claim 2, wherein a weak DC voltage is applied in the antibacterial mode, and an AC voltage or DC voltage capable of generating heat in the adsorption section is applied in the sterilization mode. 4. The method of use according to claim 2, wherein the voltage application in the bacteriostatic mode is turned off when the raw water is flowing during normal use.