JP2010069407A - Water softener and hot water supply apparatus equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problems: in the conventional water softener uses salt for regenerating a cation exchange resin, periodic salt replenishment is necessary according to the amount of used soft water and the salt replenishment requires a lot of time and labor. <P>SOLUTION: In a water softener, an anode chamber filled with a cation exchanger and a cathode chamber filled with an anion exchanger are formed by separation with a diaphragm, and the anode and cathode chambers are each provided with an electrode. When the cation and anion exchangers are regenerated, an voltage is applied across the electrodes to generate hydrogen ions and hydroxide ions, and the hydrogen ions and hydroxide ions regenerates the cation and anion exchangers, which dispenses with supply of a chemical and enables continuously obtaining soft water. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

  Conventionally, many soft water generators using ion exchange resins, reverse osmosis membranes, and electrodialysis have been proposed.For example, cation exchange resins having sodium ions as exchange groups are used, and the raw materials are produced by cation exchange resins. It is known that soft water is obtained by ion exchange of calcium ions and magnesium ions, which are hardness components contained in water, with sodium ions.

  Then, after all the sodium ions, which are exchange groups of the cation exchange resin, are 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 a cation exchange resin without using a salt, a method of obtaining soft water using a reverse osmosis membrane (see, for example, Patent Document 1), a method of obtaining soft water by electrodialysis, or ion exchange between electrodes of electrodialysis. A method of efficiently regenerating a cation exchange resin by filling a resin and using hydrogen ions generated by dissociation of water (see, for example, Patent Document 2) has been proposed.
JP-A-7-68256 JP 2006-43549 A

  However, in the method of obtaining soft water using a reverse osmosis membrane or electrodialysis, there is a problem that when the flow rate of concentrated water is decreased, the hardness component is precipitated in the concentrated portion, and the membrane is clogged. Also in the method of efficiently regenerating the cation exchange resin with hydrogen ions generated by water dissociation, if the amount of water used for regeneration is reduced, the concentration of hardness components will occur in the concentration chamber and the diaphragm will be clogged. Therefore, there is a problem that maintenance is necessary.

  In order to solve the above-described conventional problems, the water softening device of the present invention includes a positive electrode chamber filled with a cation exchanger and a negative electrode chamber filled with an anion exchanger separated by a diaphragm, and electrodes are provided in the anode chamber and the cathode chamber. The cation exchanger and the anion exchanger are regenerated by the generated hydrogen ions and hydroxide ions by applying a voltage between the electrodes during the regeneration of the cation exchanger and the anion exchanger. It is characterized by that.

  The water softening device of the present invention can regenerate the cation exchanger and the anion exchanger with the generated hydrogen ions and hydroxide ions by applying a voltage between the electrodes during regeneration. As a result, it is possible to obtain soft water by menteles without the need to supply a medicine or the like.

A water softening device according to a first aspect of the present invention separates an anode chamber filled with a cation exchanger and a cathode chamber filled with an anion exchanger with a diaphragm, and includes an electrode in the anode chamber and the cathode chamber. When an anion exchanger is regenerated, a voltage is applied between the electrodes to regenerate the cation exchanger and anion exchanger with the generated hydrogen ions and hydroxide ions, eliminating the need to supply chemicals. Soft water can be obtained with mentales.

  In addition to the first configuration, the water softening device according to the second aspect of the invention has a configuration in which a chlorine removal means is provided in the water supply channel, and water that has passed through the cathode chamber is passed through the anode chamber. Thereby, the chlorine compound in the feed water that oxidizes and degrades the cation exchanger and the anion exchanger can be removed. Deterioration of the ion exchanger can be prevented by removing residual chlorine. Further, by adopting a configuration in which water after passing through the cathode chamber is passed through the anode chamber, chlorine compounds generated in the anode chamber during regeneration can be prevented from flowing into the cathode chamber.

  In the water softening device according to the third aspect of the invention, the chlorine removing means is composed of a metal body containing at least either zinc or copper. The chlorine compound in the feed water can be removed by consuming the chlorine compound with a metal body such as zinc or copper.

  The water softening device according to the fourth aspect of the invention comprises a flow rate varying means for changing the flow rate of water flow to the water softening device during soft water sampling and ion exchanger regeneration. By reducing the water flow rate at the time of regeneration from that at the time of sampling, the amount of discarded water generated at the time of regeneration can be reduced.

  In the water softening device according to the fifth aspect of the invention, the diaphragm is composed of a bipolar membrane having a cation exchange membrane surface and an anion exchange membrane surface. By using a bipolar membrane as the diaphragm, water can be easily dissociated, so that the ion exchanger can be efficiently regenerated.

  In the water softening device according to the sixth aspect of the present invention, the ion exchanger is composed of a woven fabric, non-woven fabric, fiber or processed product having an ion exchange group, and the ion exchanger is made into a woven fabric, non-woven fabric, or fiber, so that it becomes a soft water chamber. The ion exchanger can be filled uniformly.

  7th invention mounts the water softening apparatus of the said invention in the hot water supply apparatus. By installing the water softening device in the hot water supply device, scale generation formed on the heat transfer surface of the hot water supply heat exchanger can be suppressed. Thereby, the water circuit blockage of the heat exchanger can be prevented and the heat exchange efficiency can be increased.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each embodiment, the same reference numerals are given to portions performing the same operation and the same operation, and detailed description is saved. 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. A water supply path 1, a chlorine removing means 2 provided in the water supply path 1, and a water softening means 3 for softening the water from which chlorine compounds in the water have been removed by the chlorine removing means 2 by ion exchange are provided. The water softening means 3 is a diaphragm. 4, the anode chamber 5 and the cathode chamber 6 are separated. The anode chamber 5 is provided with a cation exchanger 7 and an anode 8, and the cathode chamber 6 is provided with an anion exchanger 9 and a cathode 10. As the cation exchanger 7, one having a functional group capable of exchanging cations such as a strong acid cation exchange resin or a weak acid cation exchange resin can be used. Moreover, as the anion exchanger 9, what has the functional group which exchanges anions, such as a strong basic anion exchange resin and a weak basic ion exchange resin, can be used. The ion exchanger is not limited to any functional group as long as it can be regenerated with hydrogen ions and hydroxide ions generated by dissociation of water, but weakly acidic cation exchange resins and weak bases are easy to regenerate. A combination of cationic anion exchange resins is desirable.

The water supply channel 1 is connected to the cathode chamber inlet 11 provided in the cathode chamber 6 through the chlorine removing means 2, and the cathode chamber outlet 12 is connected to the anode chamber inlet 13. Furthermore, the anode chamber outlet 14 is connected to a soft water using device 15 that uses soft water. A regeneration switching valve 16 is provided in the flow path connecting the anode chamber outlet 14 and the soft water using device 15, and the regeneration switching valve 16 drains the flow path for supplying water to the soft water using device 15 during sampling and the waste water generated during the regeneration. The drainage channel 17 is configured to switch the channel. The drainage channel 17 is provided with a pressure loss resistor 18 for adjusting the drainage flow rate.

  The chlorine removing means 2 is filled with a metal mixture or metal alloy containing either zinc or copper, and the shape of the filler is a ring shape such as granular, Raschig rings, a saddle shape, or a bite shape. It is possible to use.

  For the diaphragm 4, polyethylene terephthalate, polyester, a non-woven fabric or a woven fabric of a fluorine-based polymer material can be used. The anode 8 and the cathode 10 use a noble metal electrode obtained by plating or sintering a noble metal such as platinum or iridium using titanium as a base material, and the shape of the electrode can be a flat plate, mesh, punching, or the like. There is no limitation on the shape of the electrode as long as a predetermined electrode area can be secured. A DC voltage is applied between the anode 8 and the cathode 10 by a DC power supply (not shown).

  The operation and action of the water softening device configured as described above will be described.

  When soft water is used in the soft water using device 15, the regeneration switching valve 16 is switched to the soft water using device 15 side. The water supplied from the water supply channel 1 is supplied to the water softening means 3 through the chlorine removing means 2. At this time, the chlorine compound in the water is removed by reacting with a metal body such as zinc or copper filled in the chlorine removing means 2, and water from which the chlorine compound deteriorating the ion exchanger is removed is supplied to the cathode chamber 6. Is done.

  The water supplied to the water softening means 3 is supplied to the anode chamber 5 after anions such as carbonate ions and chlorine ions are ion-exchanged with hydroxide ions by the anion exchanger 9 filled in the cathode chamber 6. The cation exchanger 7 filled in the anode chamber 5 exchanges cations such as sodium and calcium with hydrogen ions. The soft water generated in this way is supplied from the anode chamber outlet 14 to the soft water using device 15.

  As the device 15 using soft water, it can be used as a washing device such as a washing machine or a dishwasher, a cooking device, a steam using device in which deposition of scale becomes a problem, a hairdressing barber device, or the like. In washing machines such as washing machines and dishwashers, the hardness component inhibits the function of the surfactant, so soft water can be used to increase detergency and 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 cooking equipment, the water absorption to rice can be accelerated | stimulated by the effect of soft water, and the taste of rice, such as a rice grain collapse | crumble and the balance improvement of hardness, can be improved. Soft water also promotes 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 action during regeneration of the cation exchanger 7 and the anion exchanger 9 will be described. At the time of regeneration of the cation exchanger 7 and the anion exchanger 9, a DC voltage is applied between the anode 8 and the cathode 10, and the regeneration switching valve 16 is switched to the drainage channel 17 side. The water supplied from the water supply channel 1 is supplied to the water softening means 3 through the chlorine removing means 2. At this time, the chlorine compound in the water is removed by reacting with a metal body such as zinc or copper filled in the chlorine removing means 2, and the water from which the chlorine compound deteriorating the ion exchanger is removed is supplied to the cathode chamber 6. Is done.

  In the cathode chamber 6, hydroxide ions are generated by the dissociation of water, and the anions such as carbonate ions and chloride ions adsorbed on the anion exchanger 9 are ion-exchanged with the hydroxide ions. Chlorine ions are released. Next, water from the cathode chamber 6 is passed through the anode chamber 5, and hydrogen ions generated by the dissociation of water are generated. As a result, cations such as calcium adsorbed on the cation exchanger 7 are ion-exchanged with hydrogen ions, and cations such as calcium are released from the cation exchanger 7. At this time, it is known that not only hydrogen ions but also hypochlorous acid is generated in the anode chamber.

  In the present embodiment, the cathode chamber 6 filled with the anion exchanger 6 is passed through and then the anode chamber 5 is passed through, so that the chlorine compound generated in the anode chamber 5 flows into the cathode chamber. Can be prevented. Since the functional group of the anion exchanger 6 is weaker and more susceptible to deterioration than the functional group of the cation exchanger 7, the anode chamber 5 is allowed to flow after passing through the cathode chamber 6. Deterioration of the ion exchanger can be prevented.

  In this way, cation exchangers and anion exchangers can be regenerated using hydrogen ions and hydroxide ions generated by applying a voltage between the electrodes during regeneration, eliminating the need for supplying chemicals, etc. It becomes possible to obtain soft water.

  The drainage at the time of regeneration from the water softening means 3 is drained from the drainage channel 17 through the regeneration switching valve 16 and the pressure loss resistance 18. By providing the pressure drop resistance 18 in the drainage channel 17 in this manner, the flow rate of water to the water softening device can be changed during sampling and regeneration of the ion exchanger with a simple configuration. By reducing the water flow rate at the time of regeneration from that at the time of sampling, the amount of discarded water generated at the time of regeneration can be reduced.

  In the present embodiment, the configuration in which the pressure loss resistor 18 is provided as the water flow rate variable means is shown. However, when the method of reducing the water flow rate by intermittently supplying water without using the pressure loss resistor is used. The same effect can be obtained in.

(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to the drawings. The difference from the first embodiment is that a bipolar membrane is used for the diaphragm 4. FIG. 2 is a configuration diagram of the water softening means. The water softening means 3 separates the anode chamber 5 and the cathode chamber 6 by a bipolar membrane 19 having a cation exchange membrane surface and an anion exchange membrane surface, and the anode chamber 5 has a cation made of a nonwoven fabric having a cation exchange group. The exchanger 20 and the cathode chamber 6 are filled with an anion exchanger 21 made of a nonwoven fabric having an anion exchange group.

  In the above configuration, the operation during reproduction will be described. By applying a DC voltage between the anode 8 and the cathode 10, water dissociates at the internal interface of the bipolar film 19. In the cathode chamber 6, hydroxide ions generated by dissociation of water are ion-exchanged with anions such as carbonate ions and chloride ions adsorbed on the anion exchanger 21, and carbonate ions and chloride ions are released from the anion exchanger 21. To do. In the anode chamber 5, hydrogen ions generated by the dissociation of water are ion-exchanged with cations such as calcium adsorbed on the cation exchanger 20, and cations such as calcium are released from the cation exchanger 20.

  By using a bipolar membrane as the diaphragm, water can be easily dissociated, so that the ion exchanger can be efficiently regenerated.

As the form of the ion exchanger, granular, woven cloth, non-woven cloth or processed product thereof can be used. However, the ion exchanger can be provided in the soft water chamber 5 by making the ion exchanger into the form of woven cloth or non-woven cloth. It can be filled uniformly and processing becomes easy. Furthermore, by mixing conductive fibers and the like in the ion exchanger, the electrical resistance in the soft water chamber can be reduced, and power consumption can be reduced.

(Embodiment 3)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a configuration diagram in which the water softener is used in a heat pump water heater. In FIG. 3, the hot water supply apparatus includes a hot water storage tank 24, a heat pump unit 26 including a heat exchanger 25, a heat exchange water supply channel 27, a hot water storage tank water supply channel 28, and a hot water supply circuit 29. A heat exchanger water supply channel 27 and a hot water storage tank water supply channel 28 are connected to the lower part of the hot water storage tank 24, and a water softening device 35 and a circulation pump 36 are provided in the heat exchanger water supply channel 27.

  The operation and action of the above configuration will be described. Since the operation at the time of water softening and regeneration in the water softening device 35 is the same as that in the first embodiment, the description thereof is omitted. In the heat pump unit 26, the refrigerant circulates in the refrigerant circuit 31, the heat in the atmosphere is taken into the refrigerant by the evaporator 32, and the refrigerant is further heated to a high temperature by being compressed by the compression means 33, and is heated by the heat exchanger 25. The soft water sent from the exchanger water supply path 27 is heated. The refrigerant passes through the expansion means 34 and is sent to the evaporator 32 to take in atmospheric heat again.

  The soft water supplied to the heat exchanger 25 from the lower part of the hot water storage tank 24 through the heat exchanger water supply passage 27 by the circulation pump 36 is heated to a high temperature by the heat exchanger 25 and sent to the hot water storage tank 24 through the hot water supply circuit 29. It is done. When the user uses the hot water of the hot water supply device, the hot water adjusted to an appropriate temperature by hot water mixing or the like from the hot water supply circuit 30 at the upper part of the hot water storage tank 24 is used by the user (kitchen, washroom, bathroom, etc.). Supplied. When the hot water in the hot water storage tank 24 is used, water is replenished to the hot water storage tank 24 from the hot water storage tank water supply passage 28 below the hot water storage tank 24.

  In the heat exchanger 25, since water is rapidly heated, calcium, magnesium, and the like contained in the water adhere to the heat transfer surface as a scale to reduce the heat exchange efficiency and block the water circuit of the heat exchanger 25. There was also a possibility. However, scale supply formed on the heat transfer surface of the heat exchanger can be suppressed by supplying soft water generated by the water softening device 35 to the heat exchanger 25 as in the present embodiment. Thereby, the water circuit blockage of the heat exchanger can be prevented and the heat exchange efficiency can be increased.

  Furthermore, it is known that the use of soft water during bath cleaning such as bathing can suppress the formation of soap scum, and it is known that allergy suppression and beauty effects can be obtained. Soft water is used as washing water for skin and hair. By using this, 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 water.

  Further, by combining with a heat pump water heater having a hot water storage tank 24 as in the present embodiment, even when there is a time when soft water cannot be collected in order to regenerate the ion exchanger in the water softening device, Can be supplied to the user, so that inconvenience to the user can be eliminated.

  In addition, when a large amount of water is used, such as a heat pump water heater, and a conventional water softener is combined with a hot water supply device installed outdoors, the frequency and amount of salt replenishment is increased, and space is saved in apartment buildings and the like. However, the maintenance work such as replenishment of salt may cause a problem of poor workability, but the use of the water softener of the present embodiment makes it unnecessary to use salt and eliminates the trouble of replenishment. Can be reduced.

  As described above, the water softening device according to the present invention does not require supply of chemicals and continuously supplies soft water. Examples of devices that use soft water include washing machines, dishwashers, water heaters, and cooking appliances. It can be applied to equipment that uses water.

The block diagram of the water softening apparatus in Embodiment 1 of this invention The block diagram of the water softening means in Embodiment 2 of this invention The block diagram of the hot-water supply apparatus provided with the water softener in Embodiment 3 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Water supply path 2 Chlorine removal means 3 Softening means 4 Separation membrane 5 Anode chamber 6 Cathode chamber 7 Cation exchanger 8 Anode 9 Anion exchanger 10 Cathode 11 Cathode chamber entrance 12 Cathode chamber exit 13 Anode chamber entrance 14 Anode chamber exit 15 Equipment for using soft water 16 Regeneration switching valve 17 Drainage flow path 18 Pressure loss resistance 19 Bipolar membrane 20 Anion exchanger 21 Cation exchanger 24 Hot water storage tank 25 Heat exchanger 26 Heat pump unit 27 Heat exchanger water supply path 28 Hot water storage tank water supply path 29 Hot water supply Circuit 30 Hot-water supply circuit 31 Refrigerant circuit 32 Evaporator 33 Compression means 34 Expansion means 35 Water softening device 36 Circulation pump

Claims (7)

An anode chamber filled with a cation exchanger and a cathode chamber filled with an anion exchanger are separated and formed by a diaphragm, and electrodes are provided in the anode chamber and the cathode chamber, and the cation exchanger and the anion exchanger A water softening device, wherein a voltage is applied between the electrodes during regeneration, and the cation exchanger and anion exchanger are regenerated using the generated hydrogen ions and hydroxide ions. The water softening device according to claim 1, wherein the water supply passage is provided with a chlorine removing means, and water after passing through the cathode chamber is passed through the anode chamber. The water softening device according to claim 2, wherein the chlorine removing means is a metal body containing at least either zinc or copper. The flow rate variable means for changing the water flow rate to the water softening device is provided at the time of soft water sampling and at the time of regeneration of the cation exchanger and the anion exchanger. The water softening device according to claim 1. The water softening device according to any one of claims 1 to 4, wherein the diaphragm is a bipolar membrane having a cation exchange membrane surface and an anion exchange membrane surface. The water-softening method according to any one of claims 1 to 5, wherein the cation exchanger and the anion exchanger are granular, woven fabric, non-woven fabric, fiber or processed product having an ion exchange group. apparatus. The hot water supply apparatus provided with the water softening apparatus of any one of Claim 1 to 6.