JPH08281280A - Method for purifying and sterilizing bath water and electrolytic device for sterilization - Google Patents

Abstract

PURPOSE: To provide a device with which sterilization and purification are both assured and the efficient execution of sterilization is possible with small current by specifying the concn. of the effective chlorine generated by a sterilizing means and the total generation amt. of the chlorine. CONSTITUTION: The bath water sucked from a suction port 11 into a circulating path 1 is prevented from lowering in temp. by a heater H and flows partly to a purifying means F and the remaining water to the sterilizing means E where the purification and sterilization are respectively executed when a pump P is driven. The purified water and the sterilized water join and the joined water returns from a discharge port 2 into the bathtub. An electrolytic device which is the sterilizing means E is of a diaphragmless type in which a pair of electrode plates 21 face each other without via a diaphragm. This device electrolyzes a part of the chlorine ions included in the bath water (city water) to execute a reduction exchange of these ions to the chlorine and free chlorine, thereby imparting sterilizing power to the bath water. At this time, the concn. of the effective chlorine generated by the sterilizing means E is specified to 0.5 to 1.0ppm and the total generation amt. of the chlorine is confined to <=1.0mg per 1 hour with liter bath water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for purifying and sterilizing a bath water purifying and sterilizing apparatus and a sterilizing electrolysis apparatus which enables long-term use of the bath water by purifying and sterilizing the bath water in the bathtub.

[0002]

2. Description of the Related Art In recent years, there have been provided baths for home use that allow bathing for 24 hours. in this case,
The bath water in the bathtub can be used for a long period of time.
It must be sterilized constantly or periodically.
For this reason, in this type of bath, as shown in FIG. 5, after the bath water in the bathtub is sucked up by the pump P and heated by the heater H, purification by the purification means F and sterilization by the sterilization means E are sequentially performed. It is said to go and return to the bathtub.

As the sterilizing means E used here, an electrolyzer is generally used, as disclosed in JP-A-56-31489. Further, as the sterilization electrolyzer, which is for drinking water, a diaphragmless type is disclosed in JP-A-61-283391.

[0004]

By the way, since the bath water contains sweat and proteins that are emitted from the human body and it is difficult to remove them by physical purification, mere physical purification is used as a purification means. Since the bath water cannot be used for a long period of time by using the water purifier, for this reason, as shown in Japanese Utility Model Publication No. 4-33933, a water purifier is used. In other words, it utilizes microorganisms that decompose sweat (ammonia) and proteins.

If the sterilizing means is connected to the purifying means in series, the following problems will occur. In other words, the flow rate of circulating bath water (flow rate per unit time)
Is determined by the capacity of the bath, the treatment capacity of the purification means, and the treatment time. In this case, the flow rate of bath water passing through the sterilization means is large per hour, and therefore chlorine required for sterilization is required. In order to generate, a large electrolytic cell is required, and at the same time, the electrolytic current value must be increased. On the other hand, if too much chlorine is generated,
The chlorine concentration of the bath water in the bathtub also increases, and when it enters the purification means again, it damages the microorganisms for biological purification, and the decomposition of organic substances such as sweat and dirt cannot be achieved. From these points, in this type, the chlorine concentration in the sterilizing means is considerably low under the present circumstances, and sufficient sterilization cannot be achieved.

The present invention has been made in view of the above points, and an object of the present invention is to purify and sterilize bath water that ensures both sterilization and purification, and to perform sterilization efficiently with a small current. It is to provide a sterilizing electrolysis device that can perform.

[0007]

The bath water purifying and sterilizing method according to the present invention, however, purifies the bath water by the purifying means and the sterilizing means arranged in the circulation path for circulating the bath water in the bathtub. When performing sterilization, the concentration of effective chlorine generated by the sterilizing means is set to 0.5 ppm or more and 1.0 ppm or less, and the total chlorine generation amount is 1.0 mg or less per hour for 1 liter of bath water. It has the first feature.

As the sterilization means here, an electrolysis device having a sterilization tank accommodating a pair of electrodes facing each other without a diaphragm is preferably used. Further, as a sterilizing means, an electrolysis device in which a current is passed through the electrode for at least 1 minute within at least 72 hours, or a platinum electrode as the electrode, and a constant current control at 0.8 to 1.6 A per 1 liter of flow rate per minute The electrolyzer and the electrode used are platinum-iridium electrodes, and 0.3 to 0.
It is possible to preferably use an electrolysis device in which a constant current is controlled by 6 A, or an electrolysis device in which the voltage applied to the electrodes is constant and the application time is controlled according to the current value between the electrodes.

When the electrode in the electrolysis device is a platinum electrode, particularly when a platinum-plated electrode is used, it is preferable to use an electrode whose current polarity is reversed within 2 minutes when the electrode is continuously energized. In controlling the application time,
It is preferable that the current value is proportional to the reciprocal of the quadratic equation, or that one cycle time consisting of the application time and the application rest time is within the residence time of the bath water in the sterilization tank.

Further, the method for purifying and sterilizing bath water according to the present invention circulates the bath water in the bathtub and purifies and sterilizes the bath water by the purifying means and the sterilizing means arranged in the circulation path for this circulation. In carrying out, sterilizing with a sterilizing means installed in the bypass provided in the circulation path
It has the characteristics of At this time, the bath water passed through the sterilizing means is retained in the retention tank provided in the bypass passage and on the downstream side of the sterilizing means, or bubbles are generated by the ejector when returning the bath water to the bathtub, or the bathtub When sending the bath water inside to the purification means, it is more preferable to pass it through an activated carbon filter or an activated carbon-containing filter.

The sterilization electrolysis apparatus according to the present invention is a sterilization electrolysis apparatus arranged in a circulation path for circulating bath water in a bathtub, and has a pair of electrodes facing each other without a diaphragm. It is characterized in that it has a sterilization tank housed therein, and that the inflow port and the outflow port, which are the connecting portions with the circulation path, are arranged above the upper ends of the electrodes in the sterilization tank.

According to the first feature of the method for purifying and sterilizing bath water of the present invention, sufficient sterilization can be performed without adversely affecting the purification means using microorganisms. As the sterilizing means at this time, when using an electrolyzer having a sterilizing tank containing a pair of electrodes facing each other without a diaphragm, it becomes easy to obtain the above chlorine concentration. In addition, if the electric current is applied to the electrolyzer for at least 1 minute within at least 72 hours, even if a biofilm is formed on the electrode surface or scale such as calcium adheres, it can be recovered. The electrolysis efficiency does not deteriorate.

When the electrolysis current is controlled at a constant current, if the electrode is a platinum electrode, the flow rate per liter per minute is
0.8 to 1.6 A, if the electrode is a platinum-iridium electrode, 0.3 to 0.6 A per liter of flow rate per minute
Then, it is possible to generate chlorine capable of performing sufficient sterilization without adversely affecting the purification means using microorganisms. When the electrode is a platinum-plated electrode, if the polarity of the current is reversed within 2 minutes during continuous energization, the electrode surface can be kept clean by so-called reverse electrolysis cleaning.

In the case of constant voltage control in which the voltage applied to the electrodes is constant, if the application time is controlled according to the current value between the electrodes, it is easy to keep the chlorine concentration at a predetermined value. By making it proportional to the reciprocal of the following equation, the chlorine concentration can be reliably kept constant. Further, if one cycle time consisting of the application time and the application rest time is within the retention time of the bath water in the sterilization tank, uneven concentration does not occur.

According to the second characteristic of the method for purifying and sterilizing bath water according to the present invention, the flow rate of bath water flowing through the sterilizing means is smaller than the circulating flow rate, so that the sterilizing means is provided. Even if the chemical concentration (chlorine concentration) in is high, the chemical concentration in the whole bath water in the bathtub can be kept low, and therefore the purification means is hardly affected.

When the bath water passed through the sterilizing means is retained in the retention tank provided in the bypass passage and on the downstream side of the sterilizing means, the chemical concentration is often kept high, and the sterilizing efficiency is high. When the bath water is returned to the bathtub, bubbles are generated by the ejector, or when passing the bath water in the bathtub to the purification means through an activated carbon filter or an activated carbon-containing filter, the effect on the purification means should be avoided. Can be less.

Further, in the sterilization electrolysis apparatus of the present invention,
Since the flow rate of water (bath water) flowing between the electrodes is small, the required chlorine can be generated with a small current.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the illustrated embodiment. In FIG. 1, reference numeral 1 denotes a circulation path having a suction port 11 at one end and a discharge port 12 at the other end. A pump P and a heater H are provided on the suction port 11 side of the passage 1. Further, a purifying means F is provided on the discharge port 12 side of the circulation path 1, and a bypass passage 13 that bypasses the purifying means F is provided so that the bypass passage 1 is provided.
The sterilization means E is installed in the No. 3. The heater H has a small amount of heat to prevent the temperature of hot water from decreasing.

The bath water sucked into the circulation path 1 from the suction port 11 by driving the pump P is heated by the heater H.
When the is operating, the temperature drop is prevented here, then a part flows to the purifying means F, and the remaining part flows to the sterilizing means E. After being purified and sterilized respectively, they are joined to the discharge port. Return from 12 to the bath. The purifying means F is configured by incorporating a filter medium containing a microorganism that decomposes and removes the source of dirt and odor. As shown in FIG. 2 (a) or FIG. 2 (b), the sterilization means E is composed of an electrolysis device in which a pair of electrode plates 21, 21 are arranged in the sterilization tank 20. The electrolysis device, which is the sterilizing means E, includes a pair of electrode plates 2
1, 21 are non-diaphragm type that face each other without a diaphragm, and chloride water (tap water) contains chlorine ions (Cl
^-) have been included, the chlorine ions (Cl ^- chlorine by electrolysis a portion of) (Cl ₂₎ and free chlorine (ClO ^-)
By reducing and converting to, the bath water has sterilizing power.

Here, the inflow port 22 and the outflow port 23 connected to the bypass passage 13 are provided above the upper ends of the electrodes 21, 21 in the sterilization tank 20,
Bath water that enters the sterilization tank 20 through the inflow port 22 and exits through the outflow port 23 does not cross between the electrodes 21 and 21,
It passes through the upper part of the sterilization tank 21. In this case, as in the case where the inflow port 22 and the outflow port 23 are provided in the lower portion and the upper portion of the sterilization tank 20 as shown in FIG. 7, the bath water flows between the electrodes 21 and 21. Compared to the case where it becomes, more chlorine can be generated with less current. It is considered that this is because when the flow velocity of water between the electrodes 21 and 21 is low, the chlorine ion concentration in the vicinity of the anode is high and the chlorine concentration is also high.

By the way, a current of 2 A is applied to the electrodes 21 and 21 arranged at intervals of 3 mm in the sterilization tank 20 having a size of 100 × 80 × 15 mm, and the flow rate of bath water passing through the sterilization means E. When the chlorine concentration in the vicinity of the outflow port 23 was measured at a flow rate of 3 liter / min, 1.22 ppm was obtained when the inflow port 22 and the outflow port 23 were arranged as shown in FIG. 2 (a), and shown in FIG. 2 (b). When it is the arrangement, 1.
While it was 21 ppm, it was 0.18 ppm when the arrangement shown in FIG. 5 was used.

Then, the sterilizing means E sterilizes by the chlorine thus generated. As described above, the sterilizing means E is installed in the bypass passage 13 provided in the circulation passage 1 and passes through it. Since the flow rate to be performed is lower than the flow rate flowing through the circulation path 1, even if the chlorine concentration in the sterilizing means E is sufficient for sterilization, the chlorine concentration in the bathtub is low, and therefore, from the inside of the bathtub. The bath water sucked up and passing through the purification means F does not damage the biological purification microorganisms in the purification means F.

FIG. 3 shows another embodiment. Here, a fibrous filter in which activated carbon is impregnated or a filter TF made of fibrous activated carbon is arranged at the suction port 11, and the discharge port 12 is composed of an ejector EJ that simultaneously discharges the air sucked from the air suction port 15. There is. Further, in the bypass passage 13 and on the downstream side of the sterilizing means E, a retention tank R having a required capacity is provided.

The activated carbon in the filter TF further reduces the chlorine concentration in the bath water that adsorbs chlorine in the bath water and goes to the purification means F, so that the effect of chlorine on the purification means F is further reduced. Ejector E
The bubbles generated from J increase the contact area between the bath water and the air and make it easier for chlorine to fly. Therefore, the concentration of chlorine in the bath water is also lowered, and the influence of chlorine on the purification means F is reduced. I will end up. On the other hand, the retention tank R is intended to lengthen the contact time between the bacteria and the high-concentration chlorine in order to keep the bath water having a high chlorine concentration by passing through the sterilizing means E for a long time, Therefore, the sterilization efficiency is increased.

For the first embodiment shown in FIG. 1, the second embodiment shown in FIG. 3 and the three series arrangements shown in FIG. 5, the same sterilizing means E is operated under the same conditions. Fig. 4 shows the bactericidal effect (change of time-number of bacteria) in the case of exposure. In the case of the first embodiment (△ in the figure) and the second embodiment (○ in the figure), almost no sterilization is performed in the example of serial arrangement (● in the figure), but sterilization is performed. It is possible to confirm that the sterilization effect by the retention tank R is improved.
Further, in the second example, the residual available chlorine concentration in the bath was also measured (□ in the figure), but the concentration was kept low.

Further, in the second embodiment, the sterilizing means E
Is operated for 4 hours a day, 5 days daily
After sterilizing the bath water (maintained at a bath temperature of 41 ° C) in a bathtub for people, the water quality after 30 days was potassium permanganate consumption: 3.5 ppm Turbidity: 0.4 General bacterial count: 1200 / ml E. coli: Not detected pH: 8.1 It can be seen that, at the same time as the sterilization is performed, the purifying means F that performs biological purification is not damaged.

In the above embodiment, the bypass passage 13 is provided so that the sterilizing means E and the purifying means F are connected in parallel. However, when the bypass passage 13 is provided, the bypass passage 13 is located downstream of the purifying means F. In other words, if the bath water that has passed through the sterilization means E is to be sent to the purification means F through the bathtub, the connection position of the bypass passage 13 does not matter.

Even if the bypass passage 13 is provided with the sterilization means E, if the chlorine concentration is too low, the sterilization becomes insufficient, and if the chlorine concentration is extremely high, the microorganisms for biological purification in the purification means E are affected. There is no change in giving. Therefore, as shown in FIG. 5, when the sterilization tank 20 is connected, the relationship between the chlorine concentration near the outlet 23 of the sterilization tank 20 and the sterilization rate is examined, and the influence of the chlorine concentration on the microorganisms is examined. Where
It became like this.

That is, the turbidity is 0.40 and the number of bacteria is 3 × 10 ^5.
200 liters of bath water / ml, 100 x 80 x 15
The generated chlorine concentration is changed by circulating the sterilization tank 20 with a size of 3 mm (distance between electrodes 3 mm) at a flow rate of 3 liters / min (the sterilization tank 20 is connected in series as shown in FIG. 5) and changing the flowing current value. When the number of bacteria in the bath water was measured before and after electrolysis when electrolysis was carried out for 2 hours under varying conditions, the number of bacteria after electrolysis was 2 x 10 when the chlorine concentration was 0.3 ppm.
⁵ / ml (sterilization rate 33%), 1 x 10 when 0.4 ppm
⁵ / ml (sterilization rate 67%), 3 x 10 at 0.5 ppm
⁴ / ml (sterilization rate 90%), 2 x 10 at 0.6 ppm
^{It was 4} / ml (sterilization rate 93%), and if the chlorine concentration was 0.5 ppm or more, sterilization of one digit or more was possible.

When the bath water having a turbidity of 0.40 was electrolyzed at different chlorine concentrations for 2 hours, the turbidity of the next day was examined. The turbidity of the next day at 0.41 and 1.0 ppm is 0.41,
The turbidity of the next day at 1.1 ppm is 0.56, 1.2 pp.
When m, the turbidity of the next day was 0.82. It can be seen that when the chlorine concentration is 1.0 ppm or less, the turbidity of the next day is stable and there is no effect on the microorganisms for biological purification. However, although the chlorine concentration was kept at 1.0 ppm, the total chlorine generation amount per hour was 1.2 in 1 liter of bath water by circulating at a flow rate of 4 liter / min.
When the amount is mg, the turbidity of the next day becomes 1.10, and when the total amount of chlorine generated per hour is 1.0 mg or less in 1 liter of bath water, the turbidity of the next day is also stable. It was

From these facts, the concentration of available chlorine generated by the sterilization tank 20 is 0.5 ppm or more and 1.0 ppm or less near the outlet of the sterilization tank 20, and the total chlorine generation amount is 1 liter of bath water. On the other hand, it is understood that it is preferable to control the sterilization means E so that the sterilization means E is 1.0 mg or less per hour. It should be noted that such a chlorine concentration and a total chlorine generation amount can be obtained even in the case where the sterilizing means E shown in FIG. 5 is connected in series. However, it is advantageous to dispose the sterilizing means E in the bypass passage 13 as described above, and the chlorine concentration in this case is the concentration at the portion where the bypass passage 13 joins the circulation passage. Therefore, the sterilization tank 2 when the bypass passage 13 has the sterilization tank 20
The chlorine concentration in the vicinity of the outflow port 23 of 0 may exceed 1.0 ppm.

To obtain the above chlorine concentration and chlorine generation amount,
When the electrolysis current is controlled to a constant current, if the electrodes 21 and 21 are platinum electrodes, the flow rate is 0.8 per 1 liter per minute.
~ 1.6 A, if the electrodes 21, 21 are platinum-iridium firing electrodes, 0.3 ~ per liter of passing flow rate per minute
It should be 0.6A. When the electrolytic current value is lower than the above value, the chlorine concentration is less than 0.5 ppm, and when it is higher than the above value, the chlorine concentration exceeds 1.0 ppm.

By the way, when the electrodes 21, 21 of the sterilization tank 20 are continuously energized by constant current control, the voltage value generally decreases at first, but increases after a certain period of time. It is considered that although the scale of calcium or the like in the anode is initially removed, after a while, the adhesion hardening of calcium in the cathode becomes large and the voltage increases,
To address this point, it is preferable to reverse the polarity of the current every 15 minutes, for example. In particular, when the electrodes 21 and 21 were platinum-plated electrodes, it was found that the chlorine concentration generated was reduced to half after 1 minute of application and to about 20% after 2 minutes. For this reason, when the electrodes 21 and 21 are platinum-plated electrodes, the polarity of the applied voltage (current) may be reversed within 2 minutes. Bath water with a bacterial count of 5 × 10 ⁵ / ml 2
00 liters were circulated at a flow rate of 1 liter / min in a sterilization tank 20 (distance between platinum-plated electrodes 3 mm) having a size of 100 × 80 × 15 mm, and electrolysis was performed at a current of 1.5 A while changing the time interval of polarity reversal. When the number of bacteria in the bath water after electrolysis was measured, the number of bacteria after electrolysis was 2 × 10 ⁴ / ml (sterilization rate 96
%), When the polarity reversal interval was set to every 2 minutes, the number of bacteria after electrolysis was 5 × 10 ⁴ / ml (sterilization rate 91%),
When the polarity reversal interval is every 3 minutes, the number of bacteria after electrolysis is 2 x 1
0 ⁵ / ml (sterilization rate 68%), when the polarity reversal interval is every 4 minutes, the number of bacteria after electrolysis is 3 × 10 ⁵ / ml (sterilization rate 43%)
Therefore, there was a difference of one digit in the number of bacteria compared with the case where the polarity was reversed within 2 minutes.

If the electrodes 21, 21 of the sterilization tank 20 are kept in a non-energized state for a long time, biofilms are formed on the surfaces of the electrodes 21, 21. Moreover, if the scale attached to the surface of the electrode 21 is left for a long time, it becomes difficult for the scale to be eluted even by reverse electrolysis cleaning. For example, 100x80x1
By circulating 200 liters of suppression water at a flow rate of 3 liters / min in a sterilization tank 20 of 5 mm size (distance between platinum-iridium firing electrodes 3 mm), a chlorine concentration of 0.78 ppm is obtained by passing a current of 1.5 A. After performing electrolysis for 2 hours on the sterilization tank 20 capable of generating
When the electrolysis was restarted after being left without a current for 96 hours, the effective chlorine concentration at the outlet of the sterilization tank 20 was 0.3.
It falls to 7ppm.

However, when reverse electrolysis was carried out for 5 minutes every 24 hours, the chlorine concentration after 96 hours on the 4th day was 0.7.
It was 9 ppm, and the chlorine concentration on the 4th day after 96 hours was 0.
Since it was 75 ppm, it is preferable from the viewpoint of maintaining the performance of the electrode 21 that the current is made to flow for at least 1 minute within at least 72 hours.

When the constant voltage control is performed so that the voltage applied to the electrodes 21 and 21 is constant, the current value changes and the chlorine generation amount largely changes due to the difference in the electric conductivity of the bath water due to the water quality. That is, when the perspiration dissolves into the bath water by taking a bath, the salt NaCl in the perspiration dissolves to increase the chloride ion concentration in the bath water and increase the electrical conductivity. Since the resistance value of water decreases, more current will flow in the case of constant voltage control. Then, since the chlorine generation amount increases in proportion to the current value and the chlorine ion concentration also increases, the chlorine generation amount increases even in the case of constant current. When this point was investigated, there was a proportional relationship between the interelectrode current value during constant voltage electrolysis, which increases due to changes in water quality, and the amount of chlorine generated by electrolyzing the water at a constant current value. In the control, it was found that the chlorine generation amount increased secondarily with the increase of the current value accompanying the increase of chloride ion by bathing. The chlorine generation amount increases due to the increase in chlorine generation amount due to the increase in chlorine ion concentration, and the increase in the electric current caused by the increase in chlorine ion concentration due to the generated chlorine causes the current value to increase. Is extremely large.

Therefore, in the constant voltage control, the application time is controlled so as to be proportional to the reciprocal of the quadratic equation with respect to the current value flowing between the electrodes 21 and 21. The current value at constant voltage is A, the desired chlorine generation amount is c, the amount of chlorine generation amount generated at the current value A during constant voltage control per 1 A of current is aA + b (ppm / A), and the application time ratio is T Then, in order to be proportional to the reciprocal of the quadratic equation of the current value A, the application time ratio T obtained by the equation T = c / (A (aA + b)) (however, when T ≧ 1, T = 1
And) to electrolyze. That is, when a constant voltage (24 V) is applied between the electrodes and the current value increases due to an increase in the electrical conductivity of the bath water, the chlorine concentration (in the case of FIG. 6, per 1 A of current is increased as shown in FIG. 6 (a)). The chlorine concentration also increases, but by controlling the application time ratio T as described above, as shown in FIG. 6 (b), the chlorine concentration remains almost constant even if the current value increases. It is something that can be kept. By the way, 200 liters of bath water having a turbidity of 0.46 and an electric conductivity of 170 μS and 200 liters of bath water of 330 μS were adjusted to 100 × 80 × 15 m.
Flow rate of 3 liters / mi in a sterilization tank 20 of m size (platinum-iridium firing electrode distance 3 mm, applied voltage 24 V).
When it is circulated at n and sterilized for 2 hours, in the case where the above application time is not controlled, the sterilization rate after 24 hours is 92% and the turbidity is 0.44 for the bath water with low electric conductivity, and the high electric conductivity The degree of sterilization after 24 hours for bath water is 98
%, The turbidity was 1.38, which affected the microorganisms for biological purification with regard to the bath water with high electrical conductivity.
The above application time is controlled (desired chlorine generation amount c = 0.7).
5 ppm, a = 0.5, b = 0.15), the bath water with low electric conductivity had a sterilization rate of 93% after 24 hours and the turbidity was 0.45, and the bath water with high electric conductivity was 24
The sterilization rate after 91 hours was 91%, and the turbidity was 0.42. Sterilization and purification can be performed without being affected by electric conductivity.

In controlling the application time ratio T,
The cycle time of the application time and the rest time is the sterilization tank 20.
Retention time inside (retention time in sterilization tank 20 + retention time in retention tank R in the case of having the above-mentioned retention tank R)
Hereafter, it is desirable to set the residence time to half or less.

[0039]

As described above, in the method for purifying and sterilizing bath water of the present invention, the concentration of available chlorine is 0.5 ppm or more and 1.0 ppm or less, and the total chlorine generation amount is 1 liter of bath water. On the other hand, since the amount is 1.0 mg or less per hour, sterilization can be performed without adversely affecting the purification means using microorganisms, and long-term bath water can be used.

When an electrolysis device having a sterilization tank containing a pair of electrodes facing each other without a diaphragm is used as the sterilization means, it is possible to easily obtain chlorine in the above concentration (generation amount). Therefore, if the current is applied to the current for at least 1 minute within at least 72 hours, the performance of the electrode can be recovered even if a biofilm is formed on the electrode surface or scale such as calcium is attached. ,
Along with this, it becomes easy to maintain the sterilization ability.

When the electrolysis current is controlled to a constant current, if the electrode is a platinum electrode, the flow rate is 0.8 to 1.6 A per liter per minute, and if the electrode is a platinum-iridium electrode, Flow rate of 0.3 ~ per liter per minute
When it is set to 0.6 A, it is possible to obtain a product that can be sterilized without adversely affecting the purification means using microorganisms. If the polarity of the current is reversed within 2 minutes during continuous energization, the electrode surface can be kept clean even if the electrode is a platinum-plated electrode.
The required sterilization capacity can always be obtained.

When constant voltage control is performed so that the voltage applied to the electrodes is constant, if the application time is controlled according to the current value between the electrodes, the chlorine concentration can be controlled regardless of the water quality of the bath water (difference in electrical conductivity). It is easy to keep the predetermined value, and in particular, by making the application time proportional to the reciprocal of the quadratic equation of the current value, the chlorine concentration can be surely kept constant. Further, if one cycle time consisting of the application time and the application rest time is within the retention time of the bath water in the sterilization tank, the concentration unevenness will not occur.

Further, according to the second feature of the method for purifying and sterilizing bath water of the present invention, the flow rate of the bath water flowing through the sterilizing means becomes smaller than the circulating flow rate. Even if the chemical concentration (chlorine concentration) is the concentration required for sterilization, the chemical concentration in the whole bath water in the bathtub can be kept low, and therefore the chemical (chlorine) may affect the purification means. There is little, and therefore both purification and sterilization can be ensured.

At this time, if the bath water passed through the sterilizing means is retained in the retention tank provided in the bypass passage and on the downstream side of the sterilizing means, the state where the chemical concentration is high is maintained for a while. The sterilization efficiency becomes higher and the sterilization operation time can be shortened. If air bubbles are generated by the ejector when returning the bath water to the bathtub, the contact time between the bath water and air will increase and the chemical concentration will decrease, so the effect on the purification means can be made smaller. it can.

When the bath water in the bathtub is sent to the purifying means, even when it is passed through the activated carbon filter or the activated carbon-containing filter, the adsorption of the chemicals by the activated carbon can reduce the influence on the purifying means. In the sterilization electrolysis apparatus of the present invention, since the inlet and the outlet that are the connecting portions with the circulation path are arranged above the upper ends of the electrodes, water flowing between the electrodes (bath water) Since the flow rate is reduced and the required chlorine can be generated with a small current, efficient sterilization can be performed.

[Brief description of drawings]

FIG. 1 is a piping diagram of an embodiment of the present invention.

2A and 2B show the same sterilization tank, wherein FIG. 2A is a perspective view of an example thereof, and FIG. 2B is a perspective view of another example thereof.

FIG. 3 is a piping diagram of another embodiment.

FIG. 4 is an operation explanatory view.

FIG. 5 is a piping diagram in the case of serial arrangement.

6 (a) and 6 (b) are explanatory views showing the relationship between the chlorine concentration and the current value that changes depending on the water quality of the bath water during constant voltage control.

FIG. 7 is a perspective view of a comparative example of a sterilization tank.

[Explanation of symbols]

 1 Circulation path 13 Bypass path P Pump F Purification means E Sterilization means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location C02F 1/50 540 C02F 1/50 540B 550 550D 550L 560 560B 560F 560H 560Z

Claims (14)

[Claims] 1. Effective chlorine generated by a sterilizing means when circulating the bath water in a bathtub and purifying and sterilizing the bath water by the purifying means and sterilizing means arranged in a circulation path for this circulation. The concentration of 0.5ppm or more and 1.0ppm or less, and the total amount of chlorine generated is 1.0mg per hour for 1 liter of bath water.
A method for purifying and sterilizing bath water, comprising: 2. The method for purifying and sterilizing bath water according to claim 1, wherein as the sterilizing means, an electrolytic device having a sterilizing tank containing a pair of electrodes facing each other without a diaphragm is used. 3. The method for purifying and sterilizing bath water according to claim 1 or 2, wherein as the sterilizing means, an electrolytic device in which an electric current is passed through the electrodes for at least 1 minute within at least 72 hours is used. 4. As a sterilizing means, the electrode is a platinum electrode, and the passing flow rate is 0.8 to 1.6 A per liter per minute.
3. The method for purifying and sterilizing bath water according to claim 1 or 2, wherein an electrolysis device controlled by a constant current is used. 5. The method for purifying and sterilizing bath water according to claim 4, wherein an electrolysis device in which the polarity of current is reversed within 2 minutes when the electrodes are continuously energized. 6. As a sterilizing means, the electrode is a platinum-iridium electrode, and the passing flow rate is 0.3 per 1 liter per minute.
The method for purifying and sterilizing bath water according to claim 1 or 2, characterized in that an electrolysis device whose constant current is controlled at ˜0.6 A is used. 7. The sterilizing means is an electrolysis device in which the voltage applied to the electrodes is constant and the application time is controlled according to the current value between the electrodes. The method for purifying and sterilizing bath water according to claim 2. 8. The method for purifying and sterilizing bath water according to claim 7, wherein the application time is proportional to the reciprocal of the quadratic equation of the current value. 9. The method for purifying and sterilizing bath water according to claim 7, wherein one cycle time consisting of the application time and the application rest time is set within the retention time of the bath water in the sterilization tank. 10. A bypass passage provided in the circulation passage for circulating the bath water in the bathtub and purifying and sterilizing the bath water by the purification means and sterilization means arranged in the circulation passage for this circulation. A method for purifying and sterilizing bath water, which comprises sterilizing with a sterilizing means installed in. 11. The method for purifying and sterilizing bath water according to claim 10, wherein the bath water passed through the sterilizing means is retained in a retention tank provided in the bypass passage and on the downstream side of the sterilizing means. 12. The bubble is generated by an ejector when the bath water is returned to the bathtub.
Alternatively, the method for purifying and sterilizing bath water according to claim 10. 13. The method for purifying and sterilizing bath water according to claim 1 or 10, wherein the bath water in the bathtub is passed through an activated carbon filter or an activated carbon-containing filter when being sent to the purification means. 14. A sterilization electrolysis device arranged in a circulation path for circulating bath water in a bathtub, comprising a sterilization tank containing a pair of electrodes facing each other without a diaphragm, An electrolysis apparatus for sterilization, characterized in that an inflow port and an outflow port, which are connection parts with the circulation path, are arranged above the upper ends of the electrodes in the sterilization tank.