JP2019037920A - Sanitary device and water heater provided with the same - Google Patents

Abstract

To provide an electrolyzed water generator with high generation efficiency of active species, with less deterioration of electrode, and less generation of scale.SOLUTION: There is provided an electrolyzed water generator, including: at least one pair of opposing electrodes (1, 2); power means 9 for applying power to the electrodes (1, 2); an electrolytic cell 3 in which the electrodes (1, 2) are installed; an inflow part 4 where water flows into the electrolytic cell 3; an inter-electrode flow passage 7 through which water flows between the electrodes (1, 2); and an outflow part 5 where water flows out from the electrolytic cell 3. A flow velocity of water in the inter-electrode flow passage 7 is made uniform by a flow path resistor 6 at an upstream portion of the inter-electrode flow passage 7, thereby realizing the electrolyzed water generator with high generation efficiency of active species, with less deterioration of electrode, and less generation of scale.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a sanitary device using an electrolyzed water generating apparatus that electrolyzes water.

  Conventionally, an electrolyzed water generating device that generates electrolyzed water containing active species such as ozone and hypochlorous acid by passing water through an electrolytic cell and conducting an electrolysis by flowing an electric current between a pair of electrodes. It has been proposed (see, for example, Patent Document 1).

JP 2005-334694 A

  However, the conventional electrolyzed water generating apparatus has problems that the flow rate of water is non-uniform between the electrodes, so that the generation efficiency of the active species is low, the electrodes are easily deteriorated, and the scale is easily generated. Yes.

  An object of the present invention is to solve the conventional problems described above, and an object of the present invention is to provide a sanitary device that has high generation efficiency of active species, is less likely to deteriorate an electrode, and is less likely to generate scale.

  In order to solve the conventional problems, a sanitary device according to the present invention includes at least a pair of opposed electrodes in an electrolytic cell, power means for applying power to the electrodes, and an inflow portion where water flows into the electrolytic cell. A flow path resistor between the inflow part and the inter-electrode flow path part, and an outflow part from which the water flows out from the electrolytic cell; and an inter-electrode flow path part through which the water flows between the electrodes. And the flow rate is adjusted by allowing the water to flow through the flow path resistor.

  As a result, the flow rate of water in the inter-electrode channel portion is made uniform, so that the generation efficiency of active species can be increased, the life of the electrode can be extended, and the generation of scale can be suppressed.

  According to the present invention, it is possible to provide an electrolyzed water generating apparatus capable of generating active species with high efficiency and supplying electrolyzed water over a long period of time.

Configuration diagram of a sanitary device according to Embodiment 1 of the present invention Sectional drawing by the AA line of the electrolytic cell which concerns on the sanitary device of FIG. Sectional view by the BB line of the electrolytic cell of FIG. Configuration diagram of a water heater according to Embodiment 2 of the present invention

According to a first aspect of the present invention, in order to solve the conventional problem, a sanitary device of the present invention includes at least a pair of opposed electrodes in an electrolytic cell, power means for applying power to the electrodes, and An inflow portion into which water flows in, an outflow portion from which the water flows out from the electrolytic cell, and an interelectrode channel portion in which the water flows between the electrodes, and the inflow portion and the interelectrode channel portion A flow path resistor is provided in between, and the flow rate is adjusted by allowing the water to flow through the flow path resistor.

  As a result, water is electrolyzed to produce active species such as hypochlorous acid and ozone, and these active species having high oxidizing power decompose sebum, fatty acids, nonenal, etc., which are hardly decomposed components in water. can do.

  Furthermore, before water flows into the inter-electrode channel, the relative efficiency of the flow rate of the water increases the generation efficiency of the active species, and the deterioration of the electrode in a stable water flow state is also difficult. Yes. Along with the stabilization of the water flow, the pH becomes difficult to become a strong alkali locally, and scale formation can be suppressed.

  According to a second aspect of the invention, in particular, in the sanitary device according to the first aspect of the invention, the flow path resistor includes a plurality of openings, and the cross section of the flow path resistor in a direction perpendicular to the water flow direction has a central portion. A small number of openings are provided, and a large number of openings are provided in the peripheral portion.

  As a result, in the flow path resistor, before the water with different flow speeds flowing in from the inflow part flows into the inter-electrode flow path part, the flow speed becomes constant due to the density of the opening, so that the generation efficiency of the active species is increased, The wear of the electrode is reduced, so that the life of the electrode can be extended.

  In a third aspect of the present invention, particularly in the first or second sanitary device, the electrode includes an electrode catalyst on a surface of a metal substrate, and the at least one electrode catalyst is tantalum oxide, or tantalum oxide and platinum. It is characterized by being formed by.

  Thereby, ozone can be generated with high efficiency at a low current density, so that the oxidation treatment can be realized with power saving and the power means can be miniaturized.

  Furthermore, by forming tantalum oxide or tantalum oxide and platinum on the electrode catalyst, it is possible to generate both hypochlorous acid and ozone from one electrode at the same time. Can generate radicals.

  Furthermore, since hypochlorous acid, ozone, and radicals can be generated from one main electrode, the second electrode 2 used as the cathode does not need to use a special electrode, and cost reduction can be realized.

  In particular, the fourth aspect of the present invention is the sanitary device according to any one of the first to third aspects, the bathtub, the heating means for heating the water in the bathtub, and the water in the bathtub is in the bathtub and the above. A circulation channel that circulates between the heating unit and a circulation unit that is disposed in the circulation channel, wherein the sanitary device is disposed downstream of the circulation unit in the circulation channel. A water heater characterized by being arranged.

  Thereby, the sebum component contained in the water of a bathtub, a microbe, etc. can be oxidized, and bathtub water can be cleansed. Therefore, the bath water can be used for washing and bathing the next day.

  In addition, the adhesion of bacteria and sebum attached to the bathtub can be suppressed, and as a result, the bathtub can be removed, so the bathtub can be easily cleaned by washing the shower after draining the bathtub. can do.

  Furthermore, by circulating the water in the tub that has been oxidized in the circulation channel, sterilization in the circulation channel and adhesion of sebum components can be suppressed. As a result, the circulation of water in the tub The cleanliness in the flow path can be improved.

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

(Embodiment 1)
FIG. 1 shows a configuration diagram of a sanitary device according to a first embodiment of the present invention. FIG. 2 is a sectional view taken along line AA in FIG. As shown in FIGS. 1 and 2, the electrolyzed water generating apparatus applies power to the first electrode 1 and the second electrode 2, the electrolytic cell 3, and the first electrode 1 and the second electrode 2. Power means 9 and a flow path resistor 6. Water enters the electrolytic cell 3 from the inflow part 4, passes through the flow path resistor 6, and then is electrolyzed in the interelectrode flow path part 7. Electrolyzed water containing ozone and hypochlorous acid is discharged from the outflow part 5. Discharged.

  Here, the flow path resistor 6 will be specifically described with reference to FIGS.

  FIG. 3 is a sectional view taken along line BB in FIG. In the first embodiment, as shown in FIG. 1, since the inflow portion 4 that is an inflow port of water is located at the center in the minor axis direction of the electrolyzed water generating device, when the flow path resistor 6 does not exist, When viewed from the cross section in the water flow direction, the flow velocity of water in the interelectrode channel section 7 is faster at the center of the cross section and slower at the end of the cross section.

  The flow path resistor 6 in the present embodiment is plate-shaped, and the flow rate of water is high at the center of the cross section perpendicular to the water flow direction, and there are few openings 10 made of water passage holes. The end portion of the cross section where the flow rate of water is slow has a shape with many openings 10, and the flow path resistance of the center portion where the flow rate of water is fast is larger than that of the end portion.

  By providing the flow path resistor 6, the flow speed of the flow path resistance water is adjusted, and the flow speed of the water in the interelectrode flow path portion 7 that is the downstream portion becomes uniform regardless of the position. As a result, compared with the case where the flow path resistor 6 is not present, the active species generated by the water electrolysis is obtained from the outflow portion 5 because the proportion consumed by the cathode is reduced at the portion where the water flow rate is low. The production efficiency of the active species in the electrolyzed water can be improved 1.3 times.

  Moreover, when the flow path resistor 6 does not exist, if there is a part where the flow rate of water is partially high, the electrode life is shortened by locally scraping the electrode surface. By making the flow rate of water in the inter-electrode channel portion 7 constant by the channel resistor 6, the electrode life can be improved.

  Further, if there is a portion where the flow rate of water is partially low, the pH becomes a strong alkali locally, and scales such as calcium hydroxide and magnesium hydroxide, or calcium carbonate and magnesium carbonate are generated.

  By making the flow velocity of the water in the interelectrode channel portion 7 constant by the channel resistor 6, it is possible to prevent the pH from becoming a strong alkali locally and to suppress the generation of scale. In addition, since the deposition of scale can be suppressed by keeping the water flow rate constant, the time until the sanitary device is blocked by the scale can be extended from 200 hours to 600 hours.

  Below, the 1st electrode 1 and the 2nd electrode 2 which comprise the electrolyzed water generating apparatus provided in this sanitary device are demonstrated concretely.

  The electrodes of the first electrode 1 and the second electrode 2 are formed by attaching an electrode catalyst to the surface of a metal substrate. In addition, as the metal substrate is thicker, it is possible to suppress the influence of warpage and bending that occurs during installation in the electrolytic cell 3.

  Therefore, in the first embodiment, titanium (Ti) having a thickness of 0.5 mm to 1 mm is used as the metal substrate. The first electrode 1 is formed by adhering an electrode catalyst made of a tantalum oxide (TaOx) layer of about 1000 nm to the surface of the metal substrate.

  On the other hand, the second electrode 2 is formed by adhering an electrode catalyst made of, for example, a 1000 nm platinum (Pt) layer or an alloy layer of platinum (Pt) and iridium (Ir) to the surface of a metal substrate.

  Hereinafter, in the first electrode 1 of the first embodiment, the mechanism of ozone generation by tantalum oxide used as the electrode catalyst will be described.

  First, a thin depletion layer is formed at the interface between the surface of tantalum oxide, which is an electrode catalyst, and the cleaning water. Next, the electrons generated by the reaction of the first electrode 1 pass through the depletion layer formed on the tantalum oxide surface by the tunnel effect.

  As a result, the potential at which electrons are transferred is equal to or higher than the oxidation-reduction potential of ozone. As a result, it is considered that the ozone generation reaction is performed more efficiently and ozone can be generated.

  Conventionally, for example, lead dioxide, diamond, platinum or the like has been used as an electrode catalyst for generating ozone. However, in the case of lead, there are concerns about the impact on the environment and the human body. In the case of diamond or platinum, there are problems such as high cost and low ozone generation efficiency.

  Therefore, in Embodiment 1, tantalum oxide is used as the electrode catalyst. Tantalum oxide can generate ozone at a lower current density than conventional platinum. In addition, tantalum oxide has a feature that ozone generation efficiency increases as the current density decreases.

  In addition, tantalum oxide has a high oxygen overvoltage. Therefore, ozone and hypochlorous acid can be generated at a voltage exceeding about 1.5 V, for example, without generating oxygen at a low voltage. In particular, compared with conventional platinum, tantalum oxide can generate ozone with about ¼ power. As a result, when applied to home appliances, energy savings can be further improved.

  As described above, ozone can be generated efficiently by using tantalum oxide for the electrode catalyst.

  In the electrolyzed water generating apparatus shown in FIGS. 1 to 3, a platinum (Pt) layer or an alloy layer of platinum (Pt) and iridium (Ir) was used as the catalyst layer of the second electrode 2. Similar effects can be obtained even when other noble metals or noble metal oxides are included.

  Below, the manufacturing method of the 1st electrode 1 and the 2nd electrode 2 is demonstrated concretely.

  For example, when platinum is used as the noble metal, the first electrode 1 is prepared by first preparing a solvent adjusted so that the mixing ratio of isopropyl alcohol and ethylene glycol monoethyl ether is 4: 1, respectively.

  Then, hexachloroplatinic acid hexahydrate and tantalum ethoxide are dissolved in the prepared solvent so that the total concentration of platinum and tantalum is 1.45 mol / l (mol / liter). In this case, as will be described later, the mixing ratio of platinum and tantalum is rubbed so that the tantalum content is 75 mol% or more and the remaining portion is platinum among the constituent ratio of tantalum oxide and platinum inside the electrode catalyst. . Thereby, a preferable electrode for generating ozone can be formed.

  The first electrode 1 is manufactured by applying a tantalum oxide catalyst layer having a thickness of 1 nm to several hundreds of nanometers on the surface of a metal substrate and firing it. In this case, the thickness of the catalyst layer of the first electrode 1 is preferably 500 n or more, for example. Thereby, the membrane performance of the electrode catalyst and the adhesion strength between the membranes are improved, and further, the electrode life of the first electrode 1 and the generation efficiency of ozone are improved.

  Therefore, in the first embodiment, the first electrode 1 is formed by applying an electrode catalyst made of tantalum oxide having a thickness of 30 nm to the surface of the metal substrate 25 times and firing it. The firing temperature is desirably 300 to 700 ° C. Thereby, the adhesiveness between the metal substrate and the electrode catalyst is improved, and the electrode life can be improved. In the first embodiment, the first electrode 1 is manufactured by baking at a baking temperature of 600 ° C. and forming a tantalum oxide electrode catalyst on a metal substrate.

  In order to further improve the adhesion between the metal substrate and the electrode catalyst and improve the electrode life and ozone generation, it is preferable to roughen the surface of the metal substrate to make it rough.

  Specifically, the surface of the metal substrate is subjected to, for example, blasting or etching to roughen the surface and make it rough. Thereby, an electrode catalyst enters into the uneven part which is the rough surface formed in the surface of a metal substrate.

  As a result, the contact area between the surface of the metal substrate and the catalyst layer is improved, and a high anchor effect is obtained. At this time, the metal substrate preferably has a surface roughness of 1.5 or more. In particular, when the surface roughness Ra of the metal substrate is 3, the adhesion between the metal substrate and the electrode catalyst is further improved as compared with the surface roughness Ra1.5.

  As a result of the study, it was found that the time until the electrode catalyst peels from the metal substrate can be improved by about 1.5 times. Therefore, in Embodiment 1, the surface of the metal substrate was etched by immersing it in hot oxalic acid at 100 ° C. for 3 hours, for example.

  In addition, in order to suppress corrosion of the metal substrate and improve the electrode life, it is more preferable to form a metal layer on the metal substrate. Therefore, in the first embodiment, a method for manufacturing the first electrode 1 using platinum as the metal layer will be described below.

  First, titanium (Ti) is used as a metal substrate, and the surface is roughened by etching with hot oxalic acid to form a rough surface.

  Next, tantalum oxide was applied as an electrode catalyst in several times on the metal layer (platinum) made of platinum, and baked to form an electrode catalyst film. The 1st electrode 1 was produced by the said method.

  Thereby, it is possible to extend the time until pitting corrosion occurs on the metal substrate by about 40%. The metal layer may be iridium (Ir), ruthenium (Ru), or niobium (Nb) other than platinum, and the same effect can be obtained.

In the first embodiment, as described above, the first electrode 1 is configured by forming tantalum oxide as an electrode catalyst on the surface of a metal substrate using titanium. Thereby, the first electrode 1 can generate substantially the same amount of ozone in an area of, for example, ¼ compared to an electrode having another configuration (for example, a platinum electrode). As a result, the electrode and the electrolytic cell can be reduced in size and cost.

(Embodiment 2)
Sanitary device 11, bathtub 12, heating means 13 for heating water in bathtub 12, water in bathtub 12 exchanges heat with bathtub 12 and heating means 13, for example, a heat source such as gas or oil, or hot water. A circulation passage 14 that circulates between the circulation passage 15 and a circulation means 15 such as a pump disposed in the circulation passage 14. The second embodiment is characterized in that the sanitary device 11 is disposed on the downstream side of the flow path of the heating means 13 and the circulation means 15.

  In the second embodiment, the purpose of disposing the sanitary device 11 is to purify the bathtub water by oxidizing the water in the bathtub 12 after bathing (hereinafter referred to as bathtub water).

  That is, the bath water after bathing contains organic components such as sebum and protein such as human sweat, sebum, and dirt, and bacteria attached to the person. If this bathtub water is left for one day, the bacteria will grow using organic components such as protein and sebum as food, causing the smell of the bathtub water, and the bacteria, sebum and organic substances will adhere to the bathtub 12 and the bathtub 12 Cause slimming.

  Therefore, by oxidizing the bath water after bathing with the sanitary device 11, the bath water can be oxidized, and the odor of the bath water and the slimming of the bath 12 can be suppressed.

  Next, a specific operation of the water heater will be described.

  Bath water in the bathtub 12 after completion of bathing is introduced into the sanitary device 11 by the circulation means 15 via the circulation channel 14. The sanitary device 11 electrolyzes the bath water to generate hypochlorous acid, ozone, and radicals, which are mixed into the circulation flow path 14 and the bathtub 12.

  In particular, by disposing the sanitary device 11 on the downstream side of the flow path of the heating means 13 and the circulation means 15, ozone, hypochlorous acid and radicals are consumed by adhering to the constituent members of the heating means 13 and the circulation means 15. This is to suppress the occurrence.

  As described in Embodiment Mode 1, hypochlorous acid and ozone can oxidize sebum, proteins, fungi, and the like. Since especially hypochlorous acid has lasting power, it will be mixed in the bathtub water in the bathtub 12 without being consumed in the sanitary device 11.

  On the other hand, ozone and radicals can instantaneously decompose sebum and the like in the sanitary device 11, and also can ensure oxidation power in the circulation channel 14 and bath water in the bathtub 12 for a certain period of time and perform oxidation treatment. Therefore, by oxidizing the bath water after bathing, the odor of bath water and the cause of slimming of the bath 12 can be removed.

  Furthermore, when purifying the bath water by providing the flow path resistor 6, by flowing water having a uniform flow rate to the inter-electrode flow path portion 7, electrolysis of water while suppressing the generation of scale. By the generated active species, bacteria and lipids are efficiently decomposed.

Therefore, the water in the bathtub 12 on the next day can be cleaned, and the bathtub water can be used for bathing on the next day by washing or cooking by the heating means 13 with peace of mind. Further, by cleaning the bathtub water, it is possible to suppress the slimming of the bathtub 12 by suppressing the adhesion of bacteria and sebum adhering to the bathtub 12, so that, for example, after removing the bathtub water, The bathtub can be easily cleaned by rinsing in a shower or the like. By suppressing the generation of scale, the maintenance of the water supply / drainage route is also simplified.

  As described above, the electrolyzed water generating apparatus according to the present invention leads to improvement in generation efficiency and long-term reliability, and can also be applied to uses such as electric water heaters for gas heat sources.

DESCRIPTION OF SYMBOLS 1 1st electrode 2 2nd electrode 3 Electrolysis tank 4 Inflow part 5 Outflow part 6 Flow path resistor 7 Interelectrode flow path part 9 Electric power means 10 Opening part 11 Sanitary device 12 Bathtub 13 Heating means 14 Circulation flow path 15 Circulation means

Claims (4)

At least a pair of opposing electrodes in the electrolytic cell; power means for applying electric power to the electrode; an inflow part into which water flows into the electrolytic cell; an outflow part from which the water flows out from the electrolytic cell; A sanitary device comprising: an inter-electrode channel portion through which water flows, and a channel resistor provided between the inflow portion and the inter-electrode channel portion. The flow path resistor includes a plurality of openings, and a large number of the openings are provided in a portion of the surface of the flow path resistor that faces the flow direction of the water and that is separated from the central portion. The sanitary device according to claim 1. 3. The electrode according to claim 1, wherein the electrode includes an electrode catalyst on a surface of a metal substrate, and the at least one electrode catalyst is formed of tantalum oxide or tantalum oxide and platinum. Hygiene device. The sanitary device according to any one of claims 1 to 3, a bathtub, heating means for heating water in the bathtub, and water in the bathtub between the inside of the bathtub and the heating means. A circulation channel that circulates, and a circulation means that is arranged in the circulation channel, and the sanitary device is arranged downstream of the circulation means in the circulation channel. A water heater characterized by.

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