JP2009165955A - Water softener and hot-water supply apparatus using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water softener which can regenerate a cation-exchange resin and increase the pH of treated soft water with a low-cost constitution without using salt. <P>SOLUTION: The water softener comprises a water softening means 5 filled with a cation-exchange resin 4, an electrolysis means 2 separated into a cathode chamber 15 and an anode chamber 14 and electrolyzing water to generate alkaline water and acidic water, an acidic water tank 3 connected to the anode chamber 14 to store the acidic water generated in the anode chamber 14, a circulating pump 11 for supplying the acidic water of the acidic water tank 3 to the water softening means 5 during the regeneration of the cation-exchange resin 4, and a mixing part 9 for mixing soft water generated in the water softening means 5 with the alkaline water generated in the cathode chamber 15. The regeneration of the cation-exchange resin 4 with the acidic water generated by electrolysis of water dispenses with salt supplementation and maintenance, and the mixing of the acidic soft water with the alkaline water enables the pH increase of the treated soft water. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a water softening device for continuously supplying soft water without requiring supply of a medicine, and a hot water supply device using the water softening device.

  Many conventional water softening devices have been proposed using ion exchange resins. For example, cation exchange resins having sodium ions as functional groups are used, and hardness components contained in raw water by cation exchange resins are proposed. It is known that soft water is obtained by ion exchange of calcium ions and magnesium ions to sodium ions.

  After all the sodium ions, which are functional groups of the cation exchange resin, have been exchanged with calcium ions and magnesium ions, the ion exchange cannot be performed. Therefore, the cation exchange resin is regenerated so that the ion exchange can be performed again. There is a need.

  In the regeneration of this cation exchange resin, salt or the like is used, and it is necessary to periodically replenish the salt according to the amount of soft water used, and there is a problem that it takes time to replenish the salt.

Therefore, as a method for regenerating the cation exchange resin without using a salt, a method for regenerating the cation exchange resin with acidic water generated by electrolysis has been proposed (for example, see Patent Document 1).
JP-A-7-68256

  However, in the configuration of the conventional water softening device as disclosed in Patent Document 1, as shown in Patent Document 1, in order to regenerate the cation exchange resin with acidic water generated by electrolysis, The functional group of the cation exchange resin must be of the hydrogen ion type, and is obtained by ion exchange of calcium ions and magnesium ions, which are hardness components contained in the raw water, with the cation exchange resin to hydrogen ions. The pH of the resulting acidic soft water will be low.

  When such acidic soft water having a lowered pH is used in a boiler or a hot water supply apparatus, there is a problem that it causes corrosion of a heat exchanger or the like, and it cannot be used.

  For the purpose of neutralizing treated water, a method has been proposed in which a cation exchange resin and an anion exchange resin are filled and the ion exchange resin is regenerated with hydrogen ions and hydroxide ions. It was necessary to fill about twice the amount of the ion exchange resin, and there was a problem that the apparatus was enlarged.

  The present invention solves the above-described conventional problems, and is a water softening device that can regenerate a cation exchange resin without using salt with an inexpensive structure and can increase the pH of treated soft water, and It aims at providing a hot-water supply apparatus.

In order to solve the above-mentioned conventional problems, the water softening device of the present invention comprises a water softening means filled with a cation exchange resin, and electrolyzed water separated into a cathode chamber and an anode chamber to produce alkaline water and acidic water. Electrolyzing means, an acid water tank connected to the anode chamber for storing the acid water generated in the anode chamber, and the acid water in the acid water tank during the regeneration of the cation exchange resin A circulator pump for supplying to the means, and a mixing section for mixing the soft water generated by the water softening means and the alkaline water generated in the cathode chamber, and the cation by acidic water generated by electrolysis of water By regenerating the exchange resin, it is possible to provide a soft water device that eliminates the need for salt replenishment and maintenance, and it is possible to increase the pH of the treated soft water by mixing alkaline water with acidic soft water.

  Moreover, the hot-water supply apparatus of this invention is equipped with the water softening apparatus of any one of Claims 1-5, and when the heat exchanger which heats water is used, Scale generation formed on the heat transfer surface can be suppressed. Thereby, the water circuit blockage of the heat exchanger generated by the scale can be prevented, and a decrease in heat exchange efficiency can be surely prevented.

  The water softening device of the present invention regenerates the cation exchange resin with acidic water generated by electrolysis of water, so that soft water can be provided without the need for salt replenishment, and alkaline water can be added to acidic soft water having a lowered pH. By mixing, the pH of the treated soft water can be raised.

  The first invention comprises a water softening means filled with a cation exchange resin, an electrolysis means for electrolyzing water separated into a cathode chamber and an anode chamber to generate alkaline water and acidic water, and a connection with the anode chamber. An acidic water tank for storing the acidic water generated in the anode chamber, a circulation pump for supplying the acidic water in the acidic water tank to the water softening means during regeneration of the cation exchange resin, and the water softening A replenishment of salt by regenerating the cation exchange resin with acidic water generated by electrolysis of water, comprising a mixing section for mixing soft water generated by the means and alkaline water generated in the cathode chamber In addition, it is possible to provide a soft water device that does not require maintenance and to increase the pH of the treated soft water by mixing alkaline water with acidic soft water.

  In the second invention, in particular, the cation exchange resin of the first invention is a weak acid cation exchange resin having a methacrylic acid base structure, and the pH of the treated soft water is lowered in the weak acid cation exchange resin. Since ion exchange is not sometimes performed, it is possible to prevent an extreme decrease in pH of the treated soft water.

  In particular, the third invention calculates pH of the soft water generated by the first or second water softening means and a mixing amount of alkaline water according to the pH detected by the pH detection means. Comprising a calculation means and a control means for controlling the mixing amount of the alkaline water. Since the mixing amount of the alkaline water is changed according to the pH of the soft water treated by the water softening means, Can be obtained.

  In the fourth invention, in particular, the calculation means of the third invention estimates the ion exchange state of the cation exchange resin from the change in pH detected by the pH detection means, and the control means estimates the calculation means by the calculation means. The regeneration process is controlled from the ion exchange state of the cation exchange resin, and the cation exchange resin can be regenerated before the exchange life of the cation exchange resin by estimating the ion exchange state of the cation exchange resin. It becomes possible.

  In the fifth invention, in particular, the water softening device according to any one of the first to fourth aspects is provided with a plurality of water softening means, and the plurality of water softening means switches between softening and regeneration. Since soft water can be collected, soft water can be obtained continuously.

  A hot water supply apparatus according to a sixth aspect of the present invention is equipped with the water softening device according to any one of claims 1 to 5, and when a heat exchanger for heating water is used, Scale generation formed on the heat transfer surface can be suppressed. Thereby, the water circuit blockage of the heat exchanger generated by the scale can be prevented, and a decrease in heat exchange efficiency can be surely prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1)
FIG. 1 is a configuration diagram of a water softening device according to a first embodiment of the present invention.

  In FIG. 1, the water softening device in the present embodiment is generated by a water supply channel 1, an electrolysis unit 2 that electrolyzes water from the water supply channel 1 to generate acidic water and alkaline water, and an electrolysis unit 2. An acidic water tank 3 for storing the acidic water, a water softening means 5 filled with a cation exchange resin 4 inside, an electrolysis water supply path 6 for supplying raw water to the electrolysis means 2, and raw water for the water softening means 5 A soft water supply channel 7, a soft water flow channel 8, a mixing unit 9 for mixing alkaline water and soft water, a circulation pump 11 for supplying acidic water in the acidic water tank 3 to the water softening means 5, and The circulation channel 12 is provided.

  Further, in FIG. 1, the solid line arrows indicate the water flow direction during soft water sampling, and the broken line arrows indicate the water flow direction during regeneration of the cation exchange resin 4.

  The electrolyzing means 2 is a diaphragm 13 in which an anode chamber 14 and a cathode chamber 15 are separately formed, an anode 16 is provided in the anode chamber 14, and a cathode 17 is provided in the cathode chamber 15. Further, the anode inlet 19 provided in the anode chamber 14 and the cathode inlet 20 provided in the cathode chamber 15 are connected via the electrolytic water supply path 6. As the anode 16 and the cathode 17, a noble metal electrode obtained by plating or sintering a noble metal such as platinum or iridium using titanium as a base material is used. As the shapes of the anode 16 and the cathode 17, a flat plate, mesh, punching, or the like can be used, and the shape of the electrode is not limited as long as a predetermined electrode area can be secured.

  In addition, a DC voltage is applied between the anode 16 and the cathode 17 from the DC power source 21, and the diaphragm 13 is made of polyethylene terephthalate, polyester, a non-woven fabric or a woven fabric made of a fluorine-based polymer material. be able to.

  By applying a direct current from the direct current power source 21 between the anode 16 and the cathode 17, cations such as sodium and calcium contained in the water in the anode chamber 14 move to the cathode chamber 15 through the diaphragm 13, and the cathode chamber 15. Anions such as carbonate ions and chlorine ions contained in the water move to the anode chamber 14 through the diaphragm 13. Furthermore, ions that are electrically paired with ions that have moved by electrolysis of water are generated, so that acidic water is generated in the anode chamber 14 and alkaline water is generated in the cathode chamber 15.

  The cathode chamber outlet 22 of the cathode chamber 15 is connected to the mixing unit 9, and the anode chamber outlet 23 is connected to the acidic water tank 3. The water softening means 5 includes a cylindrical main body 5a, and a filter 24 for preventing the internal cation exchange resin 4 from leaking out and a support plate 25 for supporting the filter 24 at the upper and lower portions of the main body 5a. The upper part of the water softening means 5 is connected to the soft water supply channel 7, and the lower part of the water softening means 5 is provided with a lower connection port 27 connected to the soft water flow path 8 for supplying soft water to the device 10. Yes.

As the cation exchange resin 4, an ion exchange resin in the form of particles or fibers can be used. In the present embodiment, a particulate form capable of realizing an inexpensive configuration is shown. However, when a fibrous ion exchange resin is used, the size can be further reduced. As the cation exchange resin 4, it is desirable to use a weakly acidic cation exchange resin having a methacrylic acid-based matrix structure. By using a weakly acidic cation exchange resin, it is possible to prevent an extreme pH drop in treated soft water. .

  The water softened by the water softening means 5 is mixed with alkaline water generated in the cathode chamber 15 in the mixing unit 9, and neutral soft water is supplied to the device 10. The soft water flow path 8 is connected via a flow path switching valve 28 to a circulation flow path 12 including a device 10 that uses soft water and a circulation pump 8. Further, the soft water flow path 8 is provided with pH detecting means 29 for detecting the pH of the soft water. The pH detecting means 29 may be any as long as the pH can be estimated from the potential difference between the electrodes, and a pH sensor or a conductivity sensor using a glass electrode can be used. From the pH of the soft water detected by the pH detection means 29, a calculation means 30 for calculating the mixing amount of alkaline water and a control means 31 for controlling the mixing amount of alkaline water are provided.

  Further, the control means 31 performs an operation for controlling the operations of the circulation pump 8, the DC power supply 21, the electromagnetic valve 18, and the flow path switching valve 28.

  Next, the operation and operation of the water softening device in the present embodiment configured as described above will be described.

  When soft water is used in the device 10, the electromagnetic valve 18 is opened by the control means 31, the flow path switching valve 28 is switched so that the soft water flow path 8 and the device 10 communicate with each other, and the flow path switching valve 29 is switched to the cathode chamber outlet 22. And switching so that the upper connection port 26 of the water softening means 5 is connected. A DC voltage is applied between the anode 16 and the cathode 17 by the DC power source 21. Water flowing through the water supply channel 1 is passed through the solenoid valve 18 from the anode chamber inlet 19 and the cathode chamber inlet 20 of the electrolysis means 2 to the anode chamber 14 and the cathode chamber 15.

  Since a DC voltage is applied between the anode 16 and the cathode 17, cations such as sodium and calcium contained in the water in the anode chamber 14 are electrically attracted to the cathode 17, and the cathode chamber is passed through the diaphragm 13. 15, and negative ions such as carbonate ions and chlorine ions contained in the water in the cathode chamber 15 are electrically attracted to the anode 16 and move to the anode chamber 14 through the diaphragm 13. Furthermore, ions that are electrically paired with ions that have moved to the anode chamber 14 and the cathode chamber 15 are generated by electrolysis of water, so that acidic water is contained in the anode chamber 14 and alkaline water is contained in the cathode chamber 15. Are generated respectively.

  Thus, the acidic water obtained in the anode chamber 14 of the electrolysis means 2 is stored in the acidic water tank 3, and the alkaline water obtained in the cathode chamber 15 is passed through the mixing unit 9.

  Next, the action of water softening by the water softening means 5 will be described.

  Calcium ions and magnesium ions contained in the water passed through the water softening means 5 are replaced with hydrogen ions of the functional group of the cation exchange resin 4, and the soft water is discharged from the lower connection port 27 of the water softening means 5. Obtainable. Then, after all the hydrogen ions attached to the functional groups of the cation exchange resin 4 are exchanged with calcium ions and magnesium ions, the ion exchange cannot be performed, so that the cation exchange resin 4 is regenerated so that the ion exchange can be performed again. Need to do.

  In the present embodiment, as the cation exchange resin 4, a weakly acidic cation exchange resin having a methacrylic acid resin as a base and a carboxylic acid functional group is used. A weakly acidic cation exchange resin has a feature that it is easier to regenerate with hydrogen ions than a strongly acidic cation exchange resin, and therefore, when the cation exchange resin 4 is regenerated with hydrogen ions generated by electrolysis. In addition, since the carboxylic acid group which is a suitable resin and is a functional group does not dissociate in an acidic state, it is possible to prevent an extreme decrease in pH of the treated soft water.

  Further, the pH of the soft water whose pH is lowered by the cation exchange resin 4 can be increased by detecting the pH of the soft water by the pH detecting means 29 and mixing the alkaline water calculated by the calculating means 30 by the mixing unit 9. And neutral soft water can be used in the device 10. Examples of the equipment 10 that uses soft water include washing equipment such as washing machines and dishwashers, cooking equipment, steam-use equipment, and hairdressing barber equipment where scale deposition is a problem.

  In washing machines such as washing machines and dishwashers, the hardness component hinders the function of the surfactant, so soft water can be used to increase the cleaning power and to suppress the formation of soap scum due to the hardness component. It can prevent the clothes from becoming wrinkled and the water drops remaining on the tableware, and can provide a high-quality finish.

  Moreover, when it uses for a rice cooker etc. as a cooking appliance, the water absorption to rice can be accelerated | stimulated by the effect of soft water, and the taste of rice can be improved, such as the balance improvement of rice grain collapse and hardness. Soft water also promotes the extraction of umami components (amino acids) such as kelp, so that the taste of the cooked product can be improved by performing soft water cooking on a suitable soft water material.

  Next, the operation during regeneration of the cation exchange resin 4 will be described.

  The timing for performing the regeneration includes a manual regeneration method that is arbitrarily performed by the user and an automatic regeneration in which regeneration is performed automatically every predetermined time. The regeneration timing is determined by detecting the concentration of the hardness component, A method of regenerating when the hardness exceeding the concentration leaks, a method of regenerating when a predetermined water flow amount or a predetermined water flow time has passed, a method of regenerating at regular intervals regardless of the usage state, etc. Various timings are possible.

  In the present embodiment, the pH detection means 29 estimates the ion exchange state of the cation exchange resin 4 from the pH change of the treated soft water, and the control means 31 estimates the ion exchange of the cation exchange resin 4 estimated by the calculation means 30. It is supposed to play from the state.

  At the time of regeneration, the electromagnetic valve 18 is closed by the control means 31 and the flow path switching valve 28 is switched so that the circulation flow path 12 and the soft water flow path 8 are communicated to operate the circulation pump 8.

  Then, the acidic water in the acidic water tank 3 is supplied by the circulation pump 8 through the circulation channel 12 and the channel switching valve 28 to the soft water channel 8 and the lower connection port 27 of the water softening means 5, and the cation exchange resin. While backwashing 4 from bottom to top, the calcium ion of the cation exchange resin 4 is replaced with hydrogen ion to regenerate the resin.

  In the regeneration of the cation exchange resin 4 with acidic water, the calcium ion attached to the cation exchange resin 4 cannot be completely replaced with hydrogen ions with only one water flow. Draining with water will waste water wastefully, but by recirculating and repeatedly using acidic water used for regeneration as in this embodiment, hydrogen ions in acidic water can be recovered without waste. It can be used and the amount of water used for regeneration can be reduced.

  Further, since acidic water is supplied also to the water softening means 5 and the cathode chamber 15 of the water electrolysis means 2, the cathode 17 provided in the cathode chamber 15 simultaneously with the regeneration of the cation exchange resin 4. The scale adhering to can be removed by washing.

Generally, in order to remove the scale attached to the cathode 17, polarity inversion is performed to invert the polarity of the electrode. However, in order to perform polarity inversion, the cathode 17 is also a noble metal electrode in the same manner as the anode 16. Must be used. However, since the scale adhering to the cathode 17 can be washed and removed by passing acidic water through the cathode chamber 15, an inexpensive stainless steel electrode can be used as the cathode 17.

  Thus, by regenerating the cation exchange resin 4 with acidic water generated by electrolysis of water, it is possible to provide a water softening device that eliminates the need for salt replenishment and maintenance, and also mixes alkaline water with acidic soft water. Thus, the pH of the treated soft water can be increased.

  In addition, as the cation exchange resin 4, by using a weakly acidic cation exchange resin having a carboxylic acid functional group based on a methacrylic acid-based resin, it is possible to prevent an extreme decrease in pH of treated soft water.

  To regenerate the cation exchange resin 4, the cation exchange resin 4 is circulated and regenerated with the acid water in the acid water tank 3, so that hydrogen ions in the acid water can be used for regeneration without waste. The amount of water used can be reduced. Furthermore, since the scale adhering to the cathode 17 can be washed and removed by passing acidic water through the cathode chamber 15, an inexpensive stainless steel electrode can be used as the cathode 17.

  In the present embodiment, the electrolytic decomposition means 2 is configured to be separated into two chambers by the diaphragm 13, but the same applies even when the electrolysis means 2 using a plurality of the diaphragm 13, the cathode 17, and the anode 16 is used. Of course, the effect of can be obtained.

  In the above embodiment, the water softening device provided with one water softening means 5 has been described. However, a plurality of water softening means 5 are provided, and the water softening means 5 switches between softening and regeneration. If this is done, soft water can be sampled through the other water softening means 5 while regenerating the cation exchange resin 4 by any of the water softening means 5, so that soft water can be obtained continuously. You can also.

(Embodiment 2)
FIG. 2 is a configuration diagram of a hot water supply apparatus according to the second embodiment of the present invention. In addition, about the same part as the water softening apparatus in the said 1st Embodiment, the same code | symbol is provided and detailed description is abbreviate | omitted.

  In FIG. 2, a hot water supply device 35 in the present embodiment includes a hot water storage tank 36, a heat pump unit 38 including a heat exchanger 37, a heat exchanger water supply path 39, a hot water storage tank water supply path 40, and a hot water supply circuit 41. I have. The heat pump unit 38 is provided with a refrigerant circuit 43 having a refrigerant 42 therein, and the refrigerant circuit 43 includes an evaporator 44 that collects atmospheric heat, a compression unit 45, and an expansion unit 46 in that order. It has become.

  As the refrigerant 42, a natural refrigerant such as CO2 is used. The refrigerant 42 circulates in the refrigerant circuit 43, takes in the heat in the atmosphere by the evaporator 44, and is compressed by the compression means 45 to become a higher temperature. The heat of the refrigerant 42 is used to heat the water in the heat exchanger water supply channel 39 by the heat exchanger 37, and the refrigerant 42 whose temperature has dropped is sent to the evaporator 44 through the expansion means 46, and is again heated to atmospheric heat. Is to capture.

  A heat exchanger water supply passage 39 and a hot water storage tank water supply passage 40 are connected to the lower part of the hot water storage tank 36, and a water softening device 47 and a circulation pump 48 are provided in the heat exchanger water supply passage 39. The water softening device 47 is the same as the water softening device in the first embodiment.

The operation and action of the hot water supply apparatus in the present embodiment configured as described above will be described. Since the operation at the time of water softening and regeneration in the water softening device 47 is the same as that in the first embodiment, the description thereof is omitted.

  In the heat pump unit 38, the refrigerant 42 circulates in the refrigerant circuit 43, takes heat in the atmosphere into the refrigerant 42 by the evaporator 44, and further compresses the refrigerant 42 by the compression means 45, thereby further increasing the temperature of the refrigerant 42 and exchanging heat. The soft water sent from the heat exchanger water supply channel 39 is heated by the vessel 37. The refrigerant 42 is sent to the evaporator 44 through the expansion means 46 and takes in atmospheric heat again.

  The soft water supplied to the heat exchanger 37 from the lower part of the hot water storage tank 36 through the heat exchanger water supply path 39 by the circulation pump 48 is heated to a high temperature by the heat exchanger 37 and sent to the hot water storage tank 36 through the hot water supply circuit 41. It is done. When the user uses the hot water of the hot water supply device 35, the hot water adjusted to an appropriate temperature by hot water mixing or the like is supplied from the upper part of the hot water storage tank 36 to the user's use location (kitchen, washroom, bathroom, etc.). The When the hot water in the hot water storage tank 36 is used, water is replenished to the hot water storage tank 36 from the hot water storage tank water supply path 40 below the hot water storage tank 36.

  Conventionally, in the heat exchanger 37, water is heated rapidly, so that calcium or magnesium contained in the water adheres to the heat transfer surface as a scale to reduce heat exchange efficiency and block the water circuit of the heat exchanger 37. However, as in the present embodiment, by supplying the heat exchanger 37 with the soft water generated by the water softening device 47, scale generation formed on the heat transfer surface of the heat exchanger 37 is suppressed. can do. Thereby, the water circuit blockage of the heat exchanger 37 can be prevented, and a decrease in heat exchange efficiency can be prevented.

  Furthermore, it is known that when soft water is used for bath cleaning such as baths, it is possible to suppress the formation of soap scum and to suppress allergies and achieve a cosmetic effect. Soft water is used as washing water for skin and hair. By using it, it is possible to obtain these soft water effects, to suppress the formation of soap scum and adhesion of scales, and to obtain the effect of reducing the trouble of cleaning around the water.

  In addition, when a conventional water softening device is combined with a hot water supply device installed outdoors, such as a heat pump type hot water supply device, the frequency and amount of salt replenishment increases, and the housing complex However, there is a problem that maintenance such as replenishment of salt takes time and workability deteriorates. However, as in this embodiment, acidic water generated by electrolysis is used. By using the method for regenerating the cation exchange resin 4, the use of salt is unnecessary and the replenishment time can be reduced.

  Furthermore, the water that passes through the heat exchanger 37 is used as a source of anions necessary for obtaining acidic water having a low pH, so that water to be drained for generating acidic water is not required. In addition, it is possible to generate acidic water having a high hydrogen ion concentration in the anode chamber 14 and to reduce the size of the acidic water tank 3. Furthermore, alkaline water whose pH has been increased in the cathode chamber 15 can be passed through the water softening means 5 to prevent the pH of the treated soft water from being lowered, and the corrosion of the metal used in the heat exchanger 37 can be suppressed. can do.

  Furthermore, even when there is a time when soft water cannot be collected in order to regenerate the cation exchange resin 4 in the water softening device 47 by combining with a heat pump type hot water supply device having the hot water storage tank 36 as in the present embodiment. Since hot water can be supplied to the user from the hot water storage tank 36, inconvenience to the user can be eliminated.

As described above, the water softening device according to the present invention can supply soft water continuously without the need to supply chemicals, and is not limited to a hot water supply device, but also a washing machine, a dishwasher, a hot water supply device, cooking. It can be applied to various devices that use water, such as devices.

The block diagram of the water softening apparatus in Embodiment 1 of this invention The block diagram of the hot-water supply apparatus in Embodiment 2 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Water supply path 2 Electrolysis means 3 Acidic water tank 4 Cation exchange resin 5 Water softening means 6 Electrolysis water supply path 7 Soft water supply path 8 Soft water flow path 9 Mixing part 10 Equipment 11, 48 Circulation pump 12 Circulation flow path 13 Diaphragm 14 Anode chamber 15 Cathode chamber 16 Anode 17 Cathode 18 Solenoid valve 19 Anode entrance 20 Cathode entrance 21 DC power source 22 Cathode chamber exit 23 Anode chamber exit 24 Filter 25 Support plate 26 Upper connection port 27 Lower connection port 28 Flow path switching valve 29 pH detection Means 30 Calculation means 31 Control means 35 Hot water supply device 36 Hot water storage tank 37 Heat exchanger 38 Heat pump unit 39 Heat exchanger water supply path 40 Hot water storage tank water supply path 41 Hot water supply circuit 42 Refrigerant 43 Refrigerant circuit 44 Evaporator 45 Compression means 46 Expansion means 47 Soft water Device

Claims (6)

Water softening means filled with a cation exchange resin, electrolysis means that separates the cathode chamber and the anode chamber to electrolyze water to produce alkaline water and acidic water, and is connected to the anode chamber and produced in the anode chamber An acidic water tank for storing the generated acidic water, a circulation pump for supplying the acidic water in the acidic water tank to the water softening means when the cation exchange resin is regenerated, and soft water generated by the water softening means; A water softening device comprising a mixing unit for mixing alkaline water generated in the cathode chamber. The water softening device according to claim 1, wherein the cation exchange resin is a weakly acidic cation exchange resin having a methacrylic acid base structure. PH detecting means for detecting the pH of the soft water generated by the water softening means, computing means for calculating the mixing amount of the alkaline water according to the pH detected by the pH detecting means, and control for controlling the mixing amount of the alkaline water The water softening device according to claim 1 or 2, comprising means. The calculation means estimates the ion exchange state of the cation exchange resin from the change in pH detected by the pH detection means, and the control means performs the regeneration step from the ion exchange state of the cation exchange resin estimated by the calculation means. The water softening device according to claim 3, wherein the water softening device is controlled. The water softening device according to any one of claims 1 to 4, wherein a plurality of water softening means are provided, and water softening and regeneration are switched by the plurality of water softening means. The hot water supply apparatus carrying the water softening apparatus of any one of Claims 1-5.