Water purification device

Abstract

A water purification device (1) comprises: a filtration unit (10) that generates purified water by removing, by using a filtration material (19), a treatment object from treatment water containing the treatment object; an ozone generation unit (7) that generates ozone gas by electrolyzing water; a wash water generation unit (9) that generates wash water by mixing ozone gas into the treatment water or the purified water; and a control unit (3) that supplies the wash water to the filtration unit (10) when the filtration material is washed.

Description

Water Purification Equipment

[0001] The present disclosure relates to a water purification device.

[0002] Physical filtration, which uses activated carbon or sand as a filter material, has been known as a water treatment method for removing impurities from water. However, in water treatment devices using such filters, impurities, especially organic matter, tend to accumulate in the filter material, so they must be periodically cleaned and the organic matter must be discharged to the outside.

[0003] However, organic matter with a small molecular weight is adsorbed into the pores of the filter material, making it difficult to remove even after cleaning. Furthermore, in household water treatment devices, if the device is left unattended for an extended period of time and no cleaning is performed, organic matter accumulates on the filter material for a long period of time. If organic matter accumulates for a long period of time, the adsorbed and accumulated organic matter can serve as a nutrient source for bacteria such as Legionella pneumophila to develop and grow on the filter material, potentially causing infection in humans. Decomposition and sterilization methods using ozone are known to decompose organic matter contained in the water to be treated or the purified water and to sterilize the bacteria that have grown there.

[0004] Japanese Patent Publication No. 6-59474 Publication No. 9-75917

[0005] The water treatment system disclosed in Patent Document 1 can decompose organic matter and disinfect by combining an ozone supplying device, an ozone treatment device, and a water treatment device. However, the ozone supplying device disclosed in Patent Document 1 tends to be large because it supplies ozone by discharge. Furthermore, to use the water as purified water after decomposing organic matter and disinfecting it by supplying ozone, it is necessary to remove the ozone contained in the wash water. To remove ozone, a time balance tank must be combined with the ozone treatment device, which tends to further increase the size of the entire water treatment system.

[0006] Furthermore, in ozone treatment devices that incorporate a time balance tank, water containing ozone is temporarily stored before the ozone is removed, which means that it takes time for the purified water to become usable. Therefore, there is a problem that the purified water cannot be used immediately. Furthermore, when using a large amount of purified water, a time balance tank is required, which further increases the size of the entire device.

[0007] The present disclosure provides a compact water purification device that provides instant access to purified water.

[0008] The water purification device according to the present disclosure includes a filtration section that uses a filtration material to remove the material from water to be treated containing the material to produce purified water, an ozone generation section that generates ozone gas by electrolysis of water, a cleaning water generation section that mixes ozone gas with the water to be treated or purified water to produce cleaning water, and a control section that sends cleaning water to the filtration section when cleaning the filtration material.

[0009] According to the present disclosure, a small water purification device is provided that allows for instant use of purified water.

[0010] FIG. 1 is a schematic diagram of a water purifier 1 according to a first embodiment of the present disclosure. FIG. 2 is a schematic diagram of a filtration mode according to the first embodiment of the present disclosure. FIG. 3 is a schematic diagram of a treated water backwash mode according to the first embodiment of the present disclosure. FIG. 4 is a schematic diagram of an ozone water backwash mode according to the first embodiment of the present disclosure. FIG. 5 is a schematic diagram of a water purifier 101 according to a second embodiment of the present disclosure. FIG. 6 is a schematic diagram of a filtration mode according to the second embodiment of the present disclosure. FIG. 7 is a schematic diagram of a filtration material deployment mode and a treated water cleaning mode according to the second embodiment of the present disclosure. FIG. 8 is a schematic diagram of an ozone water cleaning mode according to the second embodiment of the present disclosure. FIG. 9 is a schematic diagram of a water purifier 201 according to a third embodiment of the present disclosure. FIG. 10 is a block diagram showing the configuration of a control unit 203 according to the third embodiment of the present disclosure. FIG. 11 is a flowchart showing the operation of the water purifier 201 according to the third embodiment of the present disclosure. FIG. 12 is a schematic diagram of a filtration mode according to the third embodiment of the present disclosure. Fig. 13 is a schematic diagram of a water to be treated cleaning mode according to the third embodiment of the present disclosure. Fig. 14 is a schematic diagram of an ozone water cleaning mode according to the third embodiment of the present disclosure. Fig. 15 is a block diagram showing a configuration of a water purifier 201 according to a fourth embodiment of the present disclosure. Fig. 16 is a flowchart showing the operation of the water purifier 201 according to the fourth embodiment of the present disclosure. Fig. 17 is a flowchart showing the operation of the water purifier 201 according to the fifth embodiment of the present disclosure. Fig. 18 is a flowchart showing the operation of the water purifier 201 according to the fifth embodiment of the present disclosure.

[0011] Hereinafter, each embodiment of the present disclosure will be described with reference to the drawings. Note that each of the following embodiments is an example of embodying the present disclosure and does not limit the technical scope of the present disclosure. Furthermore, each drawing used in each embodiment is a schematic drawing, and the ratios of the sizes and thicknesses of the components in each drawing do not necessarily reflect the actual dimensional ratios.

[0012] (Embodiment 1) ((Overall Configuration)) A water purifier 1 according to embodiment 1 will be described with reference to Fig. 1. Fig. 1 is a schematic diagram of the water purifier 1 according to embodiment 1.

[0013] As shown in FIG. 1 , the water purifier 1 purifies water containing impurities such as organic matter or bacteria, which is delivered from a water purification plant or the like via a water supply pipe 2, to make it usable for domestic use. The water purifier 1 purifies the water and cleans the filter material by executing a filtration mode, a water-to-be-treated backwash mode, and an ozone water backwash mode. Details of each mode will be described later. The water-to-be-treated backwash mode and the ozone water backwash mode are collectively referred to as the backwash mode. The water purifier 1 includes an inlet 21, a control unit 3, an ozone generator 7, a wash water generator 9, a filtration unit 10, a measurement unit 20, a purified water outlet 27, and a backwash outlet 29.

[0014] Inlet 21 is an opening through which water to be treated, which is pumped from outside water purifier 1 (for example, from a water purification plant) via water pipe 2, is introduced into water purifier 1. Inlet 21 is provided in a housing that constitutes water purifier 1, and is connected in communication with inlet pipe 22, which will be described later.

[0015] The control unit 3 controls the switching of the flow path of the water to be treated circulating within the water purifier 1 during the filtration mode, the water to be treated backwash mode, and the ozone water backwash mode. The specific flow path switching by the control unit 3 during the execution of each mode will be described later. In the control unit 3, the hardware can be realized by elements and mechanical devices, including a computer's central processing unit (CPU). The software can be realized by a computer program, etc. Therefore, these functional blocks can be realized in various forms by combining hardware and software. The control unit 3 is connected to each of the ozone generator 7, cleaning water generator 9, upstream switching valve 5, constant flow valve 24, three-way valve 25, switching valve 11, and measurement unit 20 by wire or wirelessly, and controls the operation of each component.

[0016] The ozone generator 7 is a device that takes in water to be treated and generates ozone gas by electrolyzing the water using electrodes. The ozone generator 7 is connected in communication with a second water supply pipe 23b, which will be described later, and a cleaning water production unit 9 is provided downstream of the ozone generator 7.

[0017] The cleaning water generating unit 9 is a device that generates cleaning water by mixing the water to be treated with ozone gas generated in the ozone generating unit 7. In the cleaning water generating unit 9, cleaning water can also be generated by mixing ozone gas with purified water generated in the filtration unit 10 described below, instead of the water to be treated. In this case, piping or the like is provided to supply the generated purified water to the cleaning water generating unit 9.

[0018] The filtration unit 10 captures substances to be treated, such as organic matter or bacteria, contained in the water to be treated using a filtering material 19 provided inside the filtration unit 10, and then separates and removes the substances to be treated to produce purified water. The filtration unit 10 is connected in communication with the third water supply pipe 23c, the water conveyance pipe 15, the purified water discharge pipe 26, and the backwash discharge pipe 28.

[0019] The switching valve 11 and the one end opening 13 are provided vertically above the filtration section 10 , and the water guide pipe 15 and the filtration material 19 are provided inside the filtration section 10 .

[0020] The switching valve 11 is a valve that switches the destination of water flowing into the filtration unit 10 and water discharged from the filtration unit 10 depending on the operating mode of the water purification device 1. The switching valve 11 is connected to each of the third water supply pipe 23c, the one-end opening 13, the water conduit 15, the purified water discharge pipe 26, and the backwash discharge pipe 28. The switching valve 11 is connected to the control unit 3 so as to be able to communicate wirelessly or by wire, and the water destination is switched by a signal from the control unit 3.

[0021] The one-end opening 13 is connected to an end of the third water supply pipe 23 c in a water-conveying manner by switching the water supply destination using the switching valve 11 during execution of the filtration mode, and is an opening for introducing the water to be treated flowing through the third water supply pipe 23 c into the filtration unit 10. Furthermore, the one-end opening 13 is connected to an end of the backwash discharge pipe 28 in a water-conveying manner by switching the water supply destination using the switching valve 11 during execution of the water-to-be-treated backwash mode and the ozone water backwash mode, and is an opening for supplying the water in the filtration unit 10 to the backwash discharge pipe 28. The one-end opening 13 corresponds to the other-end opening 17 described below, and is provided vertically above the other-end opening 17.

[0022] The filtering material 19 is a substance that captures substances to be treated, such as organic matter or bacteria, contained in the water to be treated, and may be, for example, activated carbon, filtering sand, zeolite, or ceramic. The filtering material 19 is provided below the filtering section 10, and a space exists above the filtering material 19 within the filtering section 10. Providing this space improves backwash efficiency in the backwash mode.

[0023] The water conduit 15 is provided within the filtration unit 10 and is a pipe connecting the upper and lower parts of the filtration unit 10, with an other-end opening 17 provided at its lower end. When the filtration mode is being performed, the untreated water that has flowed into the filtration unit 10 is conveyed from the upper part to the lower part of the filtration unit 10 via the water conduit 15. When the untreated water backwash mode and the ozone water backwash mode are being performed, the water in the filtration unit 10 that has been used to wash the filtration material 19 is conveyed from the lower part of the filtration unit 10 to the upper part of the filtration unit 10 via the water conduit 15 and then discharged to the outside of the filtration unit 10.

[0024] The other end opening 17 is buried in the filtering material 19 and is provided vertically below the one end opening 13. The other end opening 17 is an opening that supplies water in the water conduit 15 into the filtration section 10 or supplies water in the filtration section 10 to the water conduit 15.

[0025] The lower portion of the water conduit 15, including the other end opening 17, is buried in the filtration material 19. On the other hand, the upper portion of the water conduit 15 is not buried in the filtration material 19 and is connected to the switching valve 11. In other words, the water conduit 15 is a pipe that supplies water sent from the switching valve 11 to the filtration material 19 located in the lower portion of the filtration unit 10, or supplies water in the filtration unit 10 from below the filtration unit 10 to the switching valve 11.

[0026] The measuring unit 20 is provided on the purified water discharge pipe 26 (described later) and is a device that measures the water quality of the purified water produced by purification in the filtration unit 10. As the measuring unit 20, for example, a COD meter (Chemical Oxygen Demand) can be used.

[0027] The purified water outlet 27 is an opening through which the treated water filtered by the water purifier 1 is taken out as purified water (treated water) to the outside of the water purifier 1. The purified water outlet 27 is provided in a housing constituting the water purifier 1, and is connected in communication with the purified water outlet pipe 26 described below.

[0028] The backwash discharge port 29 is an opening for discharging the water to be treated or the washing water used to wash the filtration section 10 to the outside of the water purifier 1. The backwash discharge port 29 is an opening provided in the housing that constitutes the water purifier 1, and is connected in communication with the backwash discharge pipe 28.

[0029] (Flow paths and valves) The flow paths of the water purification device 1 are formed by an inlet pipe 22 , a first water supply pipe 23 a , a second water supply pipe 23 b , a third water supply pipe 23 c , a purified water discharge pipe 26 , and a backwash discharge pipe 28 .

[0030] The inlet pipe 22 is connected in communication with the inlet 21 and the upstream switching valve 5 , and is a pipe that supplies the water to be treated that has been taken into the water purifier 1 through the inlet 21 to the upstream switching valve 5 .

[0031] The upstream switching valve 5 is a valve that switches the water destination so that water is supplied from the inlet pipe 22 to either the first water supply pipe 23a or the second water supply pipe 23b. For example, a three-way motor-operated valve can be used as the upstream switching valve 5. The upstream switching valve 5 is connected to the control unit 3 wirelessly or by wire so as to be able to communicate with the control unit 3, and the water destination is switched by a signal from the control unit 3.

[0032] The upstream switching valve 5 to the filtration section 10 are connected in communication with each other by a first water supply pipe 23a, a second water supply pipe 23b, and a third water supply pipe 23c.

[0033] The first water supply pipe 23a is a pipe that connects the upstream switching valve 5 to a branch point B, which will be described later, and is used when the filtration mode and the untreated water backwash mode are performed.

[0034] The second water supply pipe 23b is a pipe that connects the upstream switching valve 5 to a branch point B described later, and is used when the ozone water backwash mode is executed. A constant flow valve 24, an ozone generator 7, and a cleaning water generator 9 are provided on the second water supply pipe 23b.

[0035] The constant flow valve 24 is a valve that keeps the flow rate of the water to be treated fed to the ozone generation unit 7 constant during operation in the ozone water backwash mode, and is connected in communication with the second water feed pipe 23b.

[0036] The third water supply pipe 23c is a pipe that connects the branch point B described later to one end side opening 13 of the filtration section 10, and is used when the filtration mode, the treated water backwash mode, and the ozone water backwash mode are executed.

[0037] The downstream end of the inlet pipe 22, the upstream end of the first water supply pipe 23a, and the upstream end of the second water supply pipe 23b are connected to each other at a branch point A. An upstream switching valve 5 is provided on the branch point A.

[0038] The downstream end of the first water supply pipe 23a, the downstream end of the second water supply pipe 23b, and the upstream end of the third water supply pipe 23c are connected to each other, and the connection point is a branch point B. A three-way valve 25 is provided on the branch point B.

[0039] The three-way valve 25 is a valve for switching the water supply source so that water is supplied from either the first water supply pipe 23 a or the second water supply pipe 23 b to the third water supply pipe 23 c. The three-way valve 25 is connected to the control unit 3 wirelessly or by wire so as to be able to communicate with the control unit 3, and the water supply destination is switched by a signal from the control unit 3.

[0040] The purified water discharge pipe 26 is connected in communication with the switching valve 11 and the purified water discharge port 27, and is a pipe that conveys the water to be treated, from which organic matter or bacteria has been removed by the filtration unit 10, to the purified water discharge port 27. A measuring unit 20 is provided on the purified water discharge pipe 26.

[0041] The backwash discharge pipe 28 is connected in communication with the switching valve 11 and the backwash discharge port 29, and is a pipe that conveys the untreated water or cleaning water used to clean the filtration section 10 to the backwash discharge port 29. The above is the configuration of the water purification device 1.

[0042] Next, the operation of the water purifier 1 will be described.

[0043] First, the operation of the water purifier 1 in the filtration mode will be described with reference to Fig. 2. Fig. 2 is a schematic diagram of the water purifier 1 in the filtration mode according to the first embodiment.

[0044] In the water purifier 1, in the filtration mode, the control unit 3 switches the flow paths, so that the upstream switching valve 5 connects the inlet pipe 22 to the first water supply pipe 23a, the three-way valve 25 connects the first water supply pipe 23a to the third water supply pipe 23c, and the switching valve 11 connects the third water supply pipe 23c to the one-end opening 13. As a result, the water to be treated containing impurities flows from the outside of the water purifier 1 into the inside of the water purifier 1 and flows through the inlet 21, the inlet pipe 22, the upstream switching valve 5, the first water supply pipe 23a, the three-way valve 25, the third water supply pipe 23c, and the switching valve 11 in this order. In other words, the inlet pipe 22, the first water supply pipe 23a, the third water supply pipe 23c, and the switching valve 11 form a purification flow path, and the water to be treated flows through the purification flow path. The water to be treated that has passed through the switching valve 11 flows into the filtration section 10 from the one-end opening 13, and then passes through the filtration material 19 provided in the filtration section 10. At this time, impurities contained in the water to be treated are adsorbed by the filtration material 19, and the water to be treated is filtered. The purified water produced by filtering the water to be treated flows through the purified water discharge pipe 26 and is sent out from the water purifier 1 through the purified water discharge port 27.

[0045] The control unit 3 terminates the filtration mode and executes the treated water backwash mode when the execution time of the filtration mode exceeds a certain time (for example, 4 hours) or when the amount of treated water exceeds a certain amount of water (for example, 7000 L).

[0046] Next, the operation of the water purifier 1 in the untreated water backwash mode will be described with reference to Fig. 3. Fig. 3 is a schematic diagram of the untreated water backwash mode according to the first embodiment.

[0047] In the water purifier 1, in the untreated water backwash mode, the control unit 3 controls the switching of the flow paths so that the upstream switching valve 5 communicates between the inlet pipe 22 and the first water supply pipe 23a, the three-way valve 25 communicates between the first water supply pipe 23a and the third water supply pipe 23c, and the switching valve 11 communicates between the third water supply pipe 23c and the water conduit 15. As a result, the untreated water flows from the outside of the water purifier 1 into the inside of the water purifier 1 and flows through the inlet 21, the inlet pipe 22, the upstream switching valve 5, the first water supply pipe 23a, the three-way valve 25, the third water supply pipe 23c, the switching valve 11, and the water conduit 15 in this order. In other words, the inlet pipe 22, the first water supply pipe 23a, the third water supply pipe 23c, and the water conduit 15 form a cleaning flow path, and the untreated water flows through the cleaning flow path. The water to be treated that has flowed through the water conduit 15 flows into the filtration unit 10 from the opening 17 at the other end thereof, and then flows through the filtration material 19 provided within the filtration unit 10. In other words, the water to be treated flows into the filtration unit 10 from the end opposite to the end when the filtration mode is being executed. The inflowing water to be treated passes through the holes in the filtration material 19 and between the holes in the filtration material 19, thereby removing the substances to be treated that are adsorbed between the holes in the filtration material 19 and between the holes in the filtration material 19. In this way, the water to be treated that has flowed in from the lower part of the filtration unit 10 cleans the filtration material 19 inside the filtration unit 10, and is then sent to the backwash discharge pipe 28 via the switching valve 11. The water to be treated then flows through the backwash discharge pipe 28 and is discharged from the backwash discharge outlet 29 to the outside of the water purifier 1.

[0048] When the execution time of the untreated water backwash mode exceeds a certain time (for example, 2 minutes), the control unit 3 ends the untreated water backwash mode and executes the ozone water backwash mode.

[0049] Next, the operation of the water purifier 1 in the ozone water backwash mode will be described with reference to Fig. 4. Fig. 4 is a schematic diagram of the water purifier 1 in the ozone water backwash mode according to the first embodiment.

[0050] In the water purifier 1, in the ozone water backwash mode, the control unit 3 controls the flow path switching, so that the upstream switching valve 5 connects the inlet pipe 22 to the second water supply pipe 23b, the three-way valve 25 connects the second water supply pipe 23b to the third water supply pipe 23c, and the switching valve 11 connects the third water supply pipe 23c to the water conduit 15. As a result, the water to be treated flows from the outside of the water purifier 1 into the water purifier 1, passes through the inlet 21, the inlet pipe 22, the upstream switching valve 5, the second water supply pipe 23b, and the constant flow valve 24, and then flows into the ozone generator 7. The water to be treated that flows into the ozone generator 7 is electrolyzed by a pair of electrodes (anode and cathode) provided inside the ozone generator 7. This electrolysis generates ozone gas. After the water to be treated containing ozone gas flows into the cleaning water generator 9, the ozone gas dissolves in the water to become cleaning water containing ozone. The cleaning water generated in the cleaning water generator 9 flows through the three-way valve 25, the third water supply pipe 23c, the switching valve 11, and the water conduit 15, in that order. The cleaning water that flows through the water conduit 15 flows into the filtration unit 10 from the other end opening 17 of the filtration unit 10, and then flows through the filtration material 19 provided in the filtration unit 10. In other words, it flows into the filtration unit 10 from the end opposite to the end into which the water to be treated flows when the filtration mode is executed. The flowing cleaning water passes through the pores of the filtration material 19 and between the filtration material 19, thereby removing the material to be treated that is adsorbed in the pores of the filtration material 19 and between the filtration material 19, and sterilizing the material with ozone. In this way, the cleaning water flowing in from the lower part of the filtration unit 10 cleans the filter material 19 inside the filtration unit 10, and is then sent to the upper part of the filtration unit 10 and sent to the backwash discharge pipe 28 via the switching valve 11. The cleaning water then flows through the backwash discharge pipe 28 and is drained from the backwash discharge port 29 to the outside of the water purifier 1.

[0051] When the execution time of the ozone water backwash mode exceeds a certain time (for example, 3 minutes), the control unit 3 ends the ozone water backwash mode and executes the filtration mode or enters a standby state in which the execution of the filtration mode is awaited.

[0052] As described above, the filtration mode, the untreated water backwash mode, and the ozone water backwash mode are repeatedly executed in the water purifier 1. In other words, the generation of purified water by the filtration unit 10 and the regeneration of the filtration unit 10 are repeatedly executed.

[0053] In most cases, during operation of the water purifier 1, the total amount of untreated water or cleaning water flowing through the filtration unit 10 in the untreated water backwash mode and the ozone water backwash mode is less than the amount of untreated water flowing through the filtration unit 10 in the filtration mode. In other words, the amount of water flowing through the filtration unit 10 during regeneration of the filtration material 19 is less than the amount of water flowing through the filtration unit 10 during production of purified water. However, depending on the operating environment of the water purifier 1, the amount of water flowing through the filtration unit 10 in the filtration mode may be equal to or greater than the total amount of water flowing through the filtration unit 10 in the untreated water backwash mode and the ozone water backwash mode. The ozone water backwash mode is executed so that the total amount of ozone water flowing through the filtration unit 10 in the ozone water backwash mode is at least the same volume as the volume of the filtration material 19.

[0054] As described above, according to the water purifier 1 of the first embodiment, the following effects can be obtained.

[0055] (1) The water purification device 1 includes a filtration unit 10 that removes the material to be treated from the water to be treated containing the material using a filtration material 19 to produce purified water, an ozone generation unit 7 that generates ozone gas by electrolysis of water, a cleaning water generation unit that mixes ozone gas with the water to be treated or purified water to produce cleaning water, and a control unit 3 that supplies cleaning water to the filtration unit 10 when cleaning the filtration material 19.

[0056] With this configuration, when backwashing the filtration unit 10, the filtration material 19 is washed with ozone water, which decomposes and disinfects organic matter accumulated in the filtration material 19. Furthermore, because the water purifier 1 of the present disclosure generates ozone by electrolysis of water, it is possible to generate ozone with a more compact device than a discharge-type ozone generator, allowing for the device to be made smaller.

[0057] (2) In the water purifier 1, the control unit 3 sends the water to be treated to the filtration unit 10 before sending the cleaning water. This allows the materials to be treated that have accumulated on the filtration material 19 to be discharged to the outside of the water purifier 1 using the water to be treated, and then the filtration unit 10 can be washed with the cleaning water. This makes it possible to efficiently decompose and disinfect organic matter.

[0058] (3) The water purifier 1 includes a purification flow path that delivers the water to be treated to a one-end opening 13 provided at one end of the filtration unit 10, and a cleaning flow path that delivers the water to an other-end opening 17 provided at the other end corresponding to the one end of the filtration unit 10. When purified water is produced by the filtration unit 10, the water purifier 1 delivers the water to be treated from the one-end opening 13 to the filtration unit 10 via the purification flow path, and when the filtration material 19 is regenerated, the water to be treated is delivered from the other-end opening 17 to the filtration unit 10 via the cleaning flow path. This configuration prevents the purified water produced in the filtration mode from mixing with the backwash wastewater generated in the untreated water backwash mode, making it possible to obtain purified water that does not contain impurities.

[0059] (4) The water purifier 1 includes a purification flow path that delivers the water to be treated to a one-end opening 13 provided at one end of the filtration unit 10, and a cleaning flow path that delivers the water to be treated to an other-end opening 17 provided at the other end corresponding to the one end of the filtration unit 10. When purified water is produced by the filtration unit 10, the water purifier 1 delivers the water to be treated from the one-end opening to the filtration unit 10 via the purification flow path, and when the filtration material 19 is regenerated, the water purifier 1 delivers cleaning water to the filtration unit 10 from the other-end opening 17 via the cleaning flow path. This configuration prevents the purified water produced in the filtration mode from mixing with the cleaning water produced in the ozone water backwash mode, thereby providing purified water that prevents the occurrence of health damage caused by ozone.

[0060] (5) In the water purifier 1, the one-end opening 13 is located vertically above the filtration section 10, and the other-end opening 17 is located vertically below the one-end opening 13. With this configuration, when the filtration mode is performed, gravity is used to filter the water to be treated, thereby improving the purification efficiency of the water to be treated. Furthermore, when the water to be treated backwash mode and the ozone water backwash mode are performed, the buoyancy of the water to be treated delivered from below and the wash water delivered from below is used to efficiently wash the materials accumulated on the filtration material 19, and the materials can be discharged to the outside of the water purifier 1.

[0061] (6) In the water purifier 1, when regenerating the filtration material 19, a volume of cleaning water at least equal to the volume of the filtration material 19 is passed through the filtration unit 10. This configuration allows the treated matter accumulated in the filtration material 19 to be efficiently discharged to the outside of the water purifier 1. Furthermore, since ozone water can simultaneously decompose and disinfect the organic matter accumulated in the filtration material 19, backwashing can be performed with less waste in time and water.

[0062] In the first embodiment, the cleaning water generating unit 9 is provided downstream of the ozone generating unit 7, but this is not limiting. For example, a housing in which the ozone generating unit 7 and the cleaning water generating unit 9 are integrated may be provided. Inside the housing, from the upstream side to the downstream side, a plate-shaped anode, a plate-shaped cathode, and a conductive film provided between the anode and the cathode are provided. In this case, water to be treated is introduced into the housing, and electrolysis of the water to be treated is performed by the anode and the cathode. Thereafter, inside the housing, ozone gas generated by electrolysis of the water to be treated on the upstream side is promptly mixed with the water to be treated. This makes it possible to generate cleaning water with a higher ozone gas concentration toward the downstream side of the housing.

[0063] The water purification device according to the present disclosure can be applied to a point-of-use (POU) water purification device or a point-of-entry (POE) water purification device.

[0064] (Embodiment 2) Physical filtration using activated carbon or sand as a filtering material has been known as a water treatment method for removing impurities from water. In water purification devices using filtering material, impurities, especially organic matter, tend to accumulate in the filtering material, so it is necessary to periodically clean the filtering material and discharge the organic matter to the outside.

[0065] However, organic matter with a small molecular weight is adsorbed into the pores of the filter material, making it difficult to remove even after cleaning. Furthermore, in household water treatment devices, organic matter accumulates on the filter material for a long period of time due to long periods of absence, leading to the water treatment device not being cleaned. If organic matter accumulates for a long period of time, the adsorbed and accumulated organic matter can serve as a nutrient source, causing bacteria such as Legionella to grow and multiply on the filter material, potentially resulting in human infection. Decomposition and sterilization methods using ozone are known to decompose organic matter contained in the water to be treated or the treated water, and to sterilize the multiplying bacteria.

[0066] The purification treatment system disclosed in Patent Document 1 is capable of decomposing organic matter and sterilizing bacteria by combining an ozone supply device, an ozone treatment device, and a filtration device. However, the problem of bacteria easily growing inside the filtration device remains unresolved when the filtration device is used infrequently, when the flow rate of cleaning water in the filtration device is low, or when maintenance of the filtration device is neglected.

[0067] Therefore, the present disclosure provides a water purifier that can suppress the growth of bacteria in the filtration section.

[0068] The water purification device of the present disclosure includes a filtration unit that uses a filtration material to remove treated materials from water to be treated that contains the materials to produce purified water, an ozone generation unit that generates ozone gas by electrolysis of water, and a cleaning water generation unit that mixes ozone gas with the water to be treated or purified water to produce ozone water.The control unit controls the execution of a filtration mode that produces purified water from the water to be treated and a cleaning mode that cleans the filtration material, and before executing an ozone water cleaning mode that constitutes the cleaning mode and supplies ozone water to the filtration unit, executes a filtration material deployment mode for a certain period of time or more in which the water to be treated is sent to the filtration unit in a direction opposite to the water supply direction of the water to be treated in the filtration mode to expand the compressed filtration material.

[0069] According to the present disclosure, a water purifier capable of suppressing bacterial growth in a filtration section is provided.

[0070] Hereinafter, each embodiment of the present disclosure will be described with reference to the drawings. Note that each of the following embodiments is an example of embodying the present disclosure and does not limit the technical scope of the present disclosure. Furthermore, each drawing used in each embodiment is a schematic drawing, and the ratios of the sizes and thicknesses of the components in each drawing do not necessarily reflect the actual dimensional ratios.

[0071] (Embodiment 2) ((Overall Configuration)) A water purifier 101 according to embodiment 2 will be described with reference to Fig. 5. Fig. 5 is a schematic diagram of the water purifier 101 according to embodiment 2.

[0072] As shown in FIG. 5 , the water purifier 101 purifies water containing impurities such as organic matter or bacteria, delivered from a water purification plant or the like via a water supply pipe 102, to make it usable for daily use. The water purifier 101 purifies the water and cleans the filter material by executing a filtration mode, a filter material deployment mode, a treated water cleaning mode, and an ozone water cleaning mode. Details of each mode will be described later. The filter material deployment mode, treated water cleaning mode, and ozone water cleaning mode are collectively referred to as the cleaning mode. The water purifier 101 includes an inlet 121, a control unit 103, an ozone generator 107, an ozone water generator 109, a filtration unit 110, a measurement unit 120, a purified water outlet 127, and a backwash outlet 129.

[0073] Inlet 121 is an opening through which water to be treated, which is pumped from outside water purifier 101 (for example, from a water purification plant) via water pipe 102, is introduced into water purifier 101. Inlet 121 is provided in a housing that constitutes water purifier 101, and is connected in communication with inlet pipe 122, which will be described later.

[0074] The control unit 103 controls switching of the flow path of the water to be treated flowing through the water purifier 101 during execution of each of the filtration mode, filtration material deployment mode, water to be treated cleaning mode, and ozone water cleaning mode. Specific flow path switching by the control unit 103 during execution of each mode will be described later. In the control unit 103, the hardware can be realized by elements and mechanical devices such as a computer's CPU (Central Processing Unit). The software can be realized by a computer program or the like. Therefore, these functional blocks can be realized in various forms by combining hardware and software. The control unit 103 is connected to each of the ozone generator 107, ozone water generator 109, upstream switching valve 105, constant flow valve 124, three-way valve 125, switching valve 111, and measurement unit 120 by wire or wirelessly, and controls the operation of each component.

[0075] The ozone generator 107 is a device that takes in the water to be treated and generates ozone gas by electrolyzing the water using electrodes. The ozone generator 107 is connected in communication with a second water supply pipe 123b (described later), and an ozone water production unit 109 is provided downstream of the ozone generator 107.

[0076] The ozonated water generating unit 109 is a device that generates ozonated water by mixing the water to be treated with ozone gas generated in the ozone generating unit 107. The ozonated water generating unit 109 can also generate ozonated water by mixing ozone gas with purified water generated in the filtration unit 110 (described later) instead of the water to be treated. In this case, a pipe or the like is provided to supply the generated purified water to the ozonated water generating unit 109.

[0077] The filtration unit 110 captures substances to be treated, such as organic matter or bacteria, contained in the water to be treated using a filtering material 119 provided inside the filtration unit 110, and then separates and removes the substances to produce purified water. The filtration unit 110 is connected in communication with the third water supply pipe 123c, the water conveyance pipe 115, the purified water discharge pipe 126, and the backwash discharge pipe 128, respectively.

[0078] The switching valve 111 and the one end opening 113 are provided vertically above the filtration section 110 , and the water guide pipe 115 and the filtration material 119 are provided inside the filtration section 110 .

[0079] The switching valve 111 is a valve that switches the destination of water flowing into the filtration unit 110 and water discharged from the filtration unit 110 depending on the operating mode of the water purification device 101. The switching valve 111 is connected to each of the third water supply pipe 123c, the one end opening 113, the water conduit 115, the purified water discharge pipe 126, and the backwash discharge pipe 128. The switching valve 111 is connected to the control unit 103 so as to be able to communicate with it wirelessly or by wire, and the water destination is switched by a signal from the control unit 103.

[0080] The one-end opening 113 is connected to an end of the third water supply pipe 123 c in a water-conveying manner by switching the water supply destination using the switching valve 111 during the filtration mode, and is an opening for introducing the water to be treated flowing through the third water supply pipe 123 c into the filtration unit 110. Furthermore, the one-end opening 113 is connected to an end of the backwash discharge pipe 128 in a water-conveying manner by switching the water supply destination using the switching valve 111 during the treatment water cleaning mode and the ozone water cleaning mode, and is an opening for supplying the water in the filtration unit 110 to the backwash discharge pipe 128. The one-end opening 113 corresponds to the other-end opening 117 described below, and is provided vertically above the other-end opening 117.

[0081] The filtration material 119 is a substance that captures substances to be treated, such as organic matter or bacteria, contained in the water to be treated. For example, activated carbon or filter sand can be used as the filtration material 119. The filtration material 119 is provided below the filtration section 110, and gaps exist between the particles of the filtration material 119. The proportion of these gaps is referred to as the porosity. The porosity of the filtration material 119 is the proportion of gaps per unit volume of the filtration material 119 expressed as a percentage. In other words, the porosity is the proportion of gaps in the portion of the filtration material 119 occupied by the filtration material 119 within the filtration section 110 (the space 130 from the bottom surface of the filtration material 119 to the top surface of the filtration material 119). Furthermore, the filtration material 119 is not filled all the way to the top surface within the filtration section 110, and a space 131 exists above the filtration material 119. The porosity of the filtration section 110 is the proportion of the volume of the space 131 above the filtration material 119 to the total volume of the filtration section 110 expressed as a percentage. The space 131 refers to an unoccupied portion of the filtering material 119 and is the space from the upper surface of the filtering material 119 to the upper surface of the filtering section 110 .

[0082] In the cleaning mode in the second embodiment, water is supplied to the filtration unit 110 from the opposite side to that in the filtration mode, causing the filtration material 119, which was compressed in the filtration mode, to expand. Therefore, by providing the space 131 above the filtration material 119, the filtration material 119 can be more easily expanded, improving the backwash efficiency in the cleaning mode. When the cleaning mode is performed, the porosity of the filtration material 119 increases and the porosity of the filtration unit 110 decreases compared to when the filtration mode ends.

[0083] The water conduit 115 is provided within the filtration unit 110 and is a pipe connecting the upper and lower parts of the filtration unit 110, with an other-end opening 117 provided at its lower end. When the filtration mode is being performed, the water to be treated that has flowed into the filtration unit 110 is conveyed from the upper part to the lower part of the filtration unit 110 via the water conduit 115. When the filtration material deployment mode, the water to be treated cleaning mode, and the ozone water cleaning mode are being performed, the water in the filtration unit 110 that has been used to clean the filtration material 119 is conveyed from the lower part of the filtration unit 110 to the upper part of the filtration unit 110 via the water conduit 115 and then sent out to the outside of the filtration unit 110.

[0084] The other end opening 117 is buried in the filtering material 119 and is provided vertically below the one end opening 113. The other end opening 117 is an opening that supplies water in the water conduit 115 into the filtration section 110, or supplies water in the filtration section 110 to the water conduit 115.

[0085] A lower portion of the water conduit 115, including the other end opening 117, is buried in the filtration material 119. On the other hand, an upper portion of the water conduit 115 is not buried in the filtration material 119 and is connected to the switching valve 111. In other words, the water conduit 115 is a pipe that supplies water sent from the switching valve 111 to the filtration material 119 located in the lower portion of the filtration unit 110, or that supplies water in the filtration unit 110 from below the filtration unit 110 to the switching valve 111.

[0086] The measuring unit 120 is provided on the purified water discharge pipe 126 (described later) and is a device that measures the quality of purified water produced by purification in the filtration unit 110. For example, a COD meter (Chemical Oxygen Demand) can be used as the measuring unit 120.

[0087] The purified water outlet 127 is an opening for removing the treated water filtered by the water purifier 101 as purified water (treated water) to the outside of the water purifier 101. The purified water outlet 127 is provided in a housing that constitutes the water purifier 101, and is connected in communication with the purified water outlet pipe 126, which will be described later.

[0088] The backwash discharge port 129 is an opening for discharging the untreated water or ozonated water used to clean the filtration section 110 to the outside of the water purifier 101. The backwash discharge port 129 is an opening provided in a housing that constitutes the water purifier 101, and is connected in communication with the backwash discharge pipe 128.

[0089] (Flow paths and valves) The flow paths of the water purifier 101 are formed by an inlet pipe 122 , a first water supply pipe 123 a , a second water supply pipe 123 b , a third water supply pipe 123 c , a purified water discharge pipe 126 , and a backwash discharge pipe 128 .

[0090] The inlet pipe 122 is connected in communication with the inlet 121 and the upstream switching valve 105 , and is a pipe that supplies the water to be treated that has been taken into the water purifier 101 from the inlet 121 to the upstream switching valve 105 .

[0091] The upstream switching valve 105 is a valve that switches the water destination so that water is supplied from the inlet pipe 122 to either the first water supply pipe 123a or the second water supply pipe 123b. For example, a three-way motor-operated valve can be used as the upstream switching valve 105. The upstream switching valve 105 is connected to the control unit 103 wirelessly or via a wire so as to be able to communicate with the control unit 103, and the water destination is switched by a signal from the control unit 103.

[0092] The upstream switching valve 105 to the filtration section 110 are connected in communication with each other by a first water supply pipe 123a, a second water supply pipe 123b, and a third water supply pipe 123c.

[0093] The first water supply pipe 123a is a pipe that connects the upstream switching valve 105 to the branch point 10B described later, and is used when the filtration mode, the filter material deployment mode, and the treated water cleaning mode are executed.

[0094] The second water supply pipe 123b is a pipe that connects the upstream switching valve 105 to a branch point 10B described later, and is used when the ozone water cleaning mode is performed. A constant flow valve 124, an ozone generator 107, and an ozone water generator 109 are provided on the second water supply pipe 123b.

[0095] The constant flow valve 124 is a valve that stabilizes the flow rate of the water to be treated that is fed to the ozone generation unit 107 at a constant flow rate during operation in the ozone water cleaning mode, and is connected in communication with the second water feed pipe 123b.

[0096] The third water supply pipe 123c is a pipe that connects the branch point 10B described later to one end side opening 113 of the filtration section 110, and is used when the filtration mode, the filtration material deployment mode, the treated water cleaning mode, and the ozone water cleaning mode are executed.

[0097] The downstream end of the inlet pipe 122, the upstream end of the first water supply pipe 123a, and the upstream end of the second water supply pipe 123b are connected to each other at a branch point 10A. An upstream switching valve 105 is provided at the branch point 10A.

[0098] The downstream end of the first water supply pipe 123a, the downstream end of the second water supply pipe 123b, and the upstream end of the third water supply pipe 123c are connected to each other at a branch point 10B. A three-way valve 125 is provided at the branch point 10B.

[0099] The three-way valve 125 is a valve for switching the water supply source so that water is supplied from either the first water supply pipe 123 a or the second water supply pipe 123 b to the third water supply pipe 123 c. The three-way valve 125 is connected to the control unit 103 wirelessly or via a wire so as to be able to communicate with the control unit 103, and the water supply destination is switched by a signal from the control unit 103.

[0100] The purified water discharge pipe 126 is connected in communication with the switching valve 111 and the purified water discharge port 127, and is a pipe for conveying the water to be treated, from which organic matter or bacteria has been removed by the filtration unit 110, to the purified water discharge port 127. A measuring unit 120 is provided on the purified water discharge pipe 126.

[0101] The backwash discharge pipe 128 is connected in communication with the switching valve 111 and the backwash discharge port 129 , and is a pipe for conveying the untreated water or ozonated water used for cleaning the filtration section 110 to the backwash discharge port 129 .

[0102] The above is the configuration of the water purifier 101.

[0103] Next, the operation of the water purifier 101 will be described.

[0104] First, the operation of the water purifier 101 in the filtration mode will be described with reference to Fig. 6. Fig. 6 is a schematic diagram of the water purifier 101 in the filtration mode according to the second embodiment.

[0105] In the filtration mode of the water purifier 101, the control unit 103 controls the switching of the flow paths, so that the upstream switching valve 105 communicates between the inlet pipe 122 and the first water supply pipe 123a, the three-way valve 125 communicates between the first water supply pipe 123a and the third water supply pipe 123c, and the switching valve 111 communicates between the third water supply pipe 123c and the one-end opening 113. As a result, the water to be treated containing impurities flows from the outside of the water purifier 101 into the inside of the water purifier 101 and flows through the inlet 121, the inlet pipe 122, the upstream switching valve 105, the first water supply pipe 123a, the three-way valve 125, the third water supply pipe 123c, and the switching valve 111 in this order. In other words, the inlet pipe 122, the first water supply pipe 123a, the third water supply pipe 123c, and the switching valve 111 form a purification flow path through which the water to be treated flows. After flowing through the switching valve 111, the water to be treated flows into the filtration unit 110 from the first opening 113 and flows through the filtration material 119 provided in the filtration unit 110. During this process, impurities in the water to be treated are adsorbed onto the filtration material 119, thereby filtering the water to be treated. Because the water to be treated flows into the filtration unit 110 from above, the filtration material 119 is gradually compressed by the water to be treated over time during the filtration mode. As a result, at the end of the filtration mode, the porosity of the filtration material 119 decreases (e.g., by 20% from the start of the filtration mode) compared to the start of the filtration mode, and the porosity of the filtration unit 110 increases (e.g., by 10% from the start of the filtration mode). The purified water produced by filtering the water to be treated flows through purified water discharge pipe 126 and is discharged from purified water discharge port 127 to the outside of water purification device 101. At the start of the filtration mode, the porosity of filter material 119 is, for example, 40%, and the porosity of filtration section 110 is, for example, 20%.

[0106] When the execution time of the filtration mode exceeds a certain time (for example, 10 hours), the control unit 103 ends the filtration mode and executes the filtration material deployment mode.

[0107] Next, the operation of the water purifier 101 in the filtering material deployment mode will be described with reference to Fig. 7. Fig. 7 is a schematic diagram of the water purifier 101 in the filtering material deployment mode according to the second embodiment.

[0108] In the water purifier 101, in the filtration material deployment mode, under the control of the control unit 103, the upstream switching valve 105 is set to a state in which the inlet pipe 122 and the first water supply pipe 123a are connected to each other, the three-way valve 125 is set to a state in which the first water supply pipe 123a and the third water supply pipe 123c are connected to each other, and the switching valve 111 is set to a state in which the third water supply pipe 123c is connected to the water conduit 115. As a result, the water to be treated flows from the outside of the water purifier 101 into the inside of the water purifier 101 and flows through the inlet 121, the inlet pipe 122, the upstream switching valve 105, the first water supply pipe 123a, the three-way valve 125, the third water supply pipe 123c, the switching valve 111, and the water conduit 115 in this order. In other words, the inlet pipe 122, the first water supply pipe 123a, the third water supply pipe 123c, and the water conduit 115 form a cleaning flow path, and the water to be treated flows through the cleaning flow path. The water to be treated that flows through the water conduit 115 flows into the filtration unit 110 from the other end opening 117 of the filtration unit 110, and then flows through the filtration material 119 provided in the filtration unit 110. In other words, the water to be treated flows into the filtration unit 110 from the end opposite to the end when the filtration mode is being executed. The inflowing water to be treated passes through the pores of the filtration material 119 and between the filtration material 119, thereby removing the substances to be treated that are adsorbed between the pores of the filtration material 119 and between the filtration material 119. At this time, the filtration material 119, which was compressed during the filtration mode, expands due to the flow rate of the water to be treated, so that the porosity of the filtration material 119 increases (for example, increases by 20% from the end of the filtration mode) and the porosity of the filtration section 110 decreases (for example, decreases by 10% from the end of the filtration mode) compared to when the filtration mode ended. In this way, the water to be treated flowing in from the lower part of the filtration section 110 cleans the filtration material 119 inside the filtration section 110, and is then sent to the upper part of the filtration section 110 and sent to the backwash discharge pipe 128 via the switching valve 111. The water to be treated then flows through the backwash discharge pipe 128 and is discharged from the backwash discharge outlet 129 to the outside of the water purifier 101.

[0109] If the execution time of the filtration material deployment mode exceeds a certain time (e.g., 2 minutes), the control unit 103 terminates the filtration material deployment mode and executes the ozone water cleaning mode. The certain time in the filtration material deployment mode is the shorter of the time from the start of the filtration material deployment mode until the porosity of the filtration unit 110 reaches the porosity before the start of the filtration mode or the time until the porosity increases by 20% or more based on the porosity of the filtration material 119 at the end of the filtration mode. Specifically, if the volumetric compression of the filtration material 119 in the filtration mode is small, the deployment rate of the filtration material 119 does not need to be low, so the filtration material deployment mode can be performed until the porosity reaches the porosity before the start of the filtration mode. On the other hand, if the volumetric compression of the filtration material 119 in the filtration mode is large, it takes time for the porosity of the filtration unit 110 to reach the porosity before the start of the filtration mode, which increases the amount of discharged water. Therefore, the filtration material deployment mode can be performed until the porosity increases by 20% or more based on the porosity of the filtration material 119 at the end of the filtration mode. Here, the increase in porosity is set to 20% or more from the viewpoints of mitigating volumetric compression of the filter material 119, the cleaning effect in the ozone water cleaning mode executed after the filter material expansion mode, and the amount of drainage in the filter material expansion mode.

[0110] Next, the operation of the water purifier 101 in the ozone water cleaning mode will be described with reference to Fig. 8. Fig. 8 is a schematic diagram showing the operation of the water purifier 101 in the ozone water cleaning mode according to the second embodiment.

[0111] In the water purifier 101, in the ozone water cleaning mode, the control unit 103 controls the flow path switching, so that the upstream switching valve 105 connects the inlet pipe 122 to the second water supply pipe 123b, the three-way valve 125 connects the second water supply pipe 123b to the third water supply pipe 123c, and the switching valve 111 connects the third water supply pipe 123c to the water conduit 115. As a result, the water to be treated flows from the outside of the water purifier 101 into the water purifier 101, passes through the inlet 121, the inlet pipe 122, the upstream switching valve 105, the second water supply pipe 123b, and the constant flow valve 124, and then flows into the ozone generator 107. The water to be treated that flows into the ozone generator 107 is electrolyzed by a pair of electrodes (anode and cathode) provided inside the ozone generator 107. This electrolysis generates ozone gas. After the water to be treated containing ozone gas flows into the ozonated water generator 109, the ozone gas dissolves in the water to form ozonated water. The ozonated water generated in the ozonated water generator 109 flows through the three-way valve 125, the third water supply pipe 123c, the switching valve 111, and the water conduit 115, in that order. The ozonated water that flows through the water conduit 115 flows into the filtration unit 110 from the other end opening 117 of the filtration unit 110 and flows through the filtration material 119 provided within the filtration unit 110. In other words, the ozonated water flows into the filtration unit 110 from the end opposite to that in the filtration mode. In other words, the ozonated water backwashes the filtration unit 110. The flow rate of the ozonated water is lower than the flow rate of the water to be treated in the filtration material deployment mode (e.g., 80% of the flow rate in the filtration material deployment mode). The inflowing ozone water passes through the holes in the filtering material 119 and between the filtering material 119, thereby removing the materials to be treated that are adsorbed in the holes in the filtering material 119 and between the holes in the filtering material 119 and sterilizing the materials with ozone. At this time, the ozone water flows in the filtering unit 110 in the direction opposite to the filtration mode, and the filtering material 119 is expanded by the flow rate of the ozone water, so that the porosity of the filtering material 119 increases compared to when the filtration mode ended (for example, a 10% increase from when the filtration mode ended), and the porosity of the filtering unit 110 decreases (for example, a 5% decrease from when the filtration mode ended).In this way, the ozone water that flows in from the lower part of the filtration unit 110 cleans the filtration material 119 inside the filtration unit 110, and is then sent to the upper part of the filtration unit 110 and sent to the backwash discharge pipe 128 via the switching valve 111. The ozone water then flows through the backwash discharge pipe 128 and is discharged from the backwash discharge port 129 to the outside of the water purifier 101.

[0112] When the execution time of the ozone water cleaning mode exceeds a certain time (for example, 2 minutes), the control unit 103 ends the ozone water cleaning mode and executes the untreated water cleaning mode.

[0113] Next, the operation of the water purifier 101 when the untreated water washing mode is executed will be described with reference to Fig. 7. Fig. 7 is a schematic diagram of the untreated water washing mode executed according to the second embodiment.

[0114] In the water purifier 101, in the treated water cleaning mode, the control unit 103 controls the switching of the flow paths so that the upstream switching valve 105 communicates between the inlet pipe 122 and the first water supply pipe 123a, the three-way valve 125 communicates between the first water supply pipe 123a and the third water supply pipe 123c, and the switching valve 111 communicates between the third water supply pipe 123c and the water conduit 115. As a result, the water to be treated flows from the outside of the water purifier 101 into the inside of the water purifier 101 and flows through the inlet 121, the inlet pipe 122, the upstream switching valve 105, the first water supply pipe 123a, the three-way valve 125, the third water supply pipe 123c, the switching valve 111, and the water conduit 115 in this order. In other words, the inlet pipe 122, the first water supply pipe 123a, the third water supply pipe 123c, and the water conduit 115 form a cleaning flow path, through which the untreated water flows. The untreated water that flows through the water conduit 115 flows into the filtration unit 110 from the other end opening 117 of the filtration unit 110 and flows through the filtration material 119 provided within the filtration unit 110. In other words, the untreated water flows into the filtration unit 110 from the end opposite to that in the filtration mode. In other words, the untreated water backwashes the filtration unit 110. The flow rate of the inflowing untreated water is greater than the flow rate of ozone water in the ozone water cleaning mode (e.g., 120% of the flow rate in the ozone water cleaning mode). The inflowing untreated water passes through the pores of the filtration material 119 and between the pores and the filtration material 119, thereby removing the treated material adsorbed between the pores and the filtration material 119. At this time, the filtration material 119 is expanded by the flow rate of the water to be treated, so that the porosity of the filtration material 119 increases (for example, increases by 20% from the end of the ozone water cleaning mode) and the porosity of the filtration unit 110 decreases (for example, decreases by 10% from the end of the ozone water cleaning mode) compared to when the ozone water cleaning mode was executed. In this way, the water to be treated flowing in from the lower part of the filtration unit 110 cleans the filtration material 119 inside the filtration unit 110, is sent to the upper part of the filtration unit 110, and is sent to the backwash discharge pipe 128 via the switching valve 111. The water to be treated then flows through the backwash discharge pipe 128 and is discharged from the backwash discharge port 129 to the outside of the water purifier 101.

[0115] When the execution time of the untreated water cleaning mode exceeds a certain time (for example, 2 minutes), the control unit 103 ends the untreated water cleaning mode and executes the filtration mode or enters a standby state to wait for the execution of the filtration mode.

[0116] As described above, the water purifier 101 repeatedly executes the filtration mode, the filtration material deployment mode, the ozone water cleaning mode, and the untreated water cleaning mode. In other words, the generation of purified water by the filtration unit 110 and the regeneration of the filtration unit 110 are repeatedly executed.

[0117] In addition, during operation of the water purifier 101, in many cases, the total amount of untreated water or ozone water flowing through the filtration unit 110 in the filtration material deployment mode, untreated water cleaning mode, and ozone water cleaning mode is less than the amount of untreated water flowing through the filtration unit 110 during the filtration mode. In other words, the amount of water flowing through the filtration unit 110 during regeneration of the filtration material 119 is less than the amount of water flowing through the filtration unit 110 during production of purified water. However, depending on the usage environment of the water purifier 101, the amount of water flowing through the filtration unit 110 in the filtration mode may be equal to or greater than the total amount of water flowing through the filtration unit 110 in the filtration material deployment mode, untreated water cleaning mode, and ozone water cleaning mode. Furthermore, the ozone water cleaning mode is executed so that the total amount of ozone water flowing through the filtration unit 110 in the ozone water cleaning mode is at least the same volume as the volume of the filtration material 119.

[0118] As described above, according to the water purifier 101 of the second embodiment, the following effects can be obtained.

[0119] (1) The water purification device 101 includes a filtration unit 110 that removes the material to be treated from the water to be treated containing the material using a filtration material 119 to produce purified water, an ozone generation unit 107 that generates ozone gas by electrolysis of water, an ozone water generation unit 109 that mixes ozone gas with the water to be treated or purified water to produce ozone water, and a control unit 103 that supplies ozone water to the filtration unit 110 when cleaning the filtration material 119.

[0120] With this configuration, when backwashing the filtration section 110, the filtration section 110 is washed with ozone water, which is cleaning water containing ozone, and this makes it possible to decompose and disinfect organic matter accumulated in the filtration material 119.

[0121] (2) In the water purifier 101, the control unit 103 sends the water to be treated to the filtration unit 110 before sending the ozone water. This allows the compressed filtration material 119 to expand in the filtration mode, making it easier for the filtration material 119 to be cleaned with ozone water when the ozone water cleaning mode is executed. Furthermore, after the materials to be treated accumulated on the filtration material 119 are discharged outside the water purifier with the water to be treated, the filtration unit 110 can be cleaned with ozone water. Furthermore, the effects of the materials to be treated accumulated on the filtration material 119 can be suppressed, and the filtration material 119 can be cleaned with ozone water. Therefore, decomposition and sterilization of organic matter can be efficiently performed.

[0122] (3) In the water purifier 101, the control unit 103 supplies ozonated water at a flow rate in the ozonated water cleaning mode that is slower than the flow rate of the water being treated in the filtration material deployment mode. This allows the filtration unit 110 to be cleaned with ozonated water after the filtration material 119 has been deployed. Furthermore, by reducing the flow rate of the ozonated water, the ozone concentration in the ozonated water can be increased. Therefore, cleaning with high-concentration ozonated water efficiently decomposes organic matter and sterilizes, further enhancing the sterilization effect.

[0123] (4) In the water purifier 101, the control unit 103 controls the flow rate of the water to be treated in the water-to-be-treated cleaning mode to be greater than the flow rate of the ozone water in the ozone water cleaning mode. By increasing the flow rate of the water to be treated, the filtration material 119 can be re-decomposed, allowing the decomposition products of organic matter generated during the ozone water cleaning mode to be discharged to the outside of the water purifier 101. Furthermore, since the amount of ozone water remaining in the filtration unit 110 can be reduced, purified water can be obtained that can reduce the occurrence of health damage caused by ozone.

[0124] The present disclosure has been described above based on Embodiment 2. Embodiment 2 is merely an example, and it will be understood by those skilled in the art that various modifications are possible in the combination of each component or each treatment process, and that such modifications are also within the scope of the present disclosure.

[0125] In the second embodiment, the ozone water generating unit 109 is provided downstream of the ozone generating unit 107, but this is not limiting. For example, a housing in which the ozone generating unit 107 and the ozone water generating unit 109 are integrated may be provided. Inside the housing, from the upstream side to the downstream side, a plate-shaped anode, a plate-shaped cathode, and a conductive film provided between the anode and the cathode are provided. In this case, water to be treated is introduced into the housing, and electrolysis of the water to be treated is performed by the anode and the cathode. Thereafter, ozone gas generated by electrolysis of the water to be treated on the upstream side is promptly mixed with the water to be treated inside the housing. This makes it possible to generate ozone water with an increasing ozone gas concentration toward the downstream side of the housing.

[0126] In the second embodiment, the relationship between the flow rates in the filtration material deployment mode, the ozone water cleaning mode, and the treated water cleaning mode is defined, but it may be defined using, for example, the flow rate. Even in this case, the relationship between the flow rates in the modes defined in the second embodiment is the same as the relationship between the flow rates.

[0127] In the second embodiment, the time for each of the filtration material deployment mode, the ozone water cleaning mode, and the treated water cleaning mode is specified, but this is merely an example, and a different time may be specified for each of the modes, for example, because the time required to obtain the effect of each mode varies depending on the shape of the filtration section 110, the type of filtration material 119, the flow rate in each mode, etc.

[0128] The water purification device according to the present disclosure can be applied to a point-of-use (POU) water purification device or a point-of-entry (POE) water purification device.

[0129] Physical filtration using activated carbon or sand as a filtering material has been known as a water treatment method for removing impurities from water (see, for example, Patent Document 2). In water purification devices using filtering material, impurities, particularly organic matter, tend to accumulate in the filtering material, so it is necessary to periodically clean the filtering material and discharge the organic matter to the outside.

[0130] However, organic matter with a small molecular weight is adsorbed into the pores of the filter material, making it difficult to remove even after cleaning. Furthermore, in the case of a home water purifier, cleaning operations are not performed due to long periods of absence, which leads to long periods of accumulation of organic matter on the filter material. If organic matter accumulates for a long time, the adsorbed and accumulated organic matter serves as a nutrient source, potentially causing the development and proliferation of bacteria such as Legionella pneumophila on the filter material, which can potentially infect humans. Decomposition and sterilization methods using ozone are known to decompose organic matter contained in the water to be treated and the treated water, and to sterilize the proliferating bacteria (see, for example, Patent Document 1).

[0131] The water treatment system disclosed in Patent Document 2 describes an efficient backwashing method for a water purifier using activated carbon. As described, backwashing is an effective method for restoring the filter material of a water purifier. However, friction during backwashing can lead to wear on the filter material, which is one of the factors that shortens the filter material's lifespan.

[0132] Furthermore, the water treatment system disclosed in Patent Document 1 combines an ozone supply device with a water purification device to decompose organic matter and disinfect bacteria. However, it is known that the strong oxidation and decomposition reactions caused by ozone affect not only organic matter but also filtration materials. In particular, in water treatment systems using activated carbon, there is a risk that the oxidation and decomposition reactions may damage the filtration material, leading to a shortened lifespan of the filtration material.

[0133] The present disclosure reduces wear and damage to the filter material due to cleaning of the filter material in a water purification device, contributing to extending the life of the filter material and reducing the frequency of replacement.

[0134] The water purification device of the present disclosure includes a filtration unit that removes the treated substance from the treated water containing the treated substance using a filtration material to produce purified water, and a concentration measurement unit that measures the concentration of the treated substance in the purified water.The cleaning water generation unit is an ozone water generation unit that generates ozone water by mixing ozone gas with the treated water or the purified water.The control unit includes a memory unit that stores a reference value for the concentration of the treated substance, a treated substance comparison unit that compares the measured concentration of the treated substance in the purified water with the reference value for the concentration of the treated substance, a determination unit that determines that the treatment material is in a cleaning-required state and that the cleaning of the filtration material is required when the concentration of the treated substance in the purified water produced in a filtration mode that produces purified water from the treated water is equal to or greater than the reference value for the concentration of the treated substance, and a cleaning execution unit that executes a cleaning mode to clean the filtration material when the determination unit determines that the treatment material is in a cleaning-required state.

[0135] According to the present disclosure, it is possible to provide a water purifier that reduces wear and damage to the filter material due to cleaning of the filter material, thereby contributing to extending the life of the filter material and reducing the frequency of replacement.

[0136] Hereinafter, each embodiment of the present disclosure will be described with reference to the drawings. Note that each of the following embodiments is an example of embodying the present disclosure and does not limit the technical scope of the present disclosure. Furthermore, each drawing used in each embodiment is a schematic drawing, and the ratios of the sizes and thicknesses of the components in each drawing do not necessarily reflect the actual dimensional ratios.

[0137] (Third Embodiment) ((Overall Configuration)) A water purifier 201 according to a third embodiment will be described with reference to Figures 9 and 10. Figure 9 is a schematic diagram of the water purifier 201 according to the third embodiment. Figure 10 is a block diagram showing the configuration of a control unit 203 according to the third embodiment of the present disclosure.

[0138] The water purifier 201 purifies the water to be treated, which is water delivered via a water supply pipe 202 from a water purification plant or the like and contains impurities such as organic matter or bacteria as the treated substance, to make it usable for domestic use. The water purifier 201 purifies the water to be treated and cleans the filter material by executing a filtration mode, a treated water cleaning mode, and an ozone water cleaning mode. Details of each mode will be described later. The treated water cleaning mode and the ozone water cleaning mode are collectively referred to as the cleaning mode. As shown in FIG. 9 , the water purifier 201 includes an inlet 221, an ozone generator 207, an ozone water generator 209, a filtration unit 210, a concentration measurement unit 220, a purified water outlet 227, a backwash outlet 229, and a control unit 203.

[0139] Inlet 221 is an opening through which water to be treated, which is pumped from outside water purifier 201, such as a water purification plant, via water pipe 202, is introduced into water purifier 201. Inlet 221 is provided in a housing that constitutes water purifier 201, and is connected in communication with inlet pipe 222, which will be described later.

[0140] The ozone generator 207 is a device that takes in the water to be treated and generates ozone gas by electrolyzing the water using electrodes. The ozone generator 207 is connected in communication with a second water supply pipe 223b, which will be described later, and an ozone water production unit 209 is provided downstream of the ozone generator 207.

[0141] The ozone water generator 209 is a device that generates cleaning water (ozone water) by mixing the water to be treated with ozone gas generated in the ozone generator 207. In the ozone water generator 209, instead of the water to be treated, ozone gas can be mixed with purified water generated in the filtration unit 210 described below to generate cleaning water. In this case, a pipe or the like is provided to supply the generated purified water to the ozone water generator 209.

[0142] The filtration unit 210 produces purified water by capturing, separating, and removing substances to be treated, such as organic matter or bacteria, contained in the water to be treated using a filtering material 219 provided inside the filtration unit 210. The filtration unit 210 is connected in communication with the third water supply pipe 223c, the water conduit 215, the purified water discharge pipe 226, and the backwash discharge pipe 228. The purified water is water from which substances to be treated, such as organic matter or bacteria, have been separated and removed.

[0143] A switching valve 211 and a first end opening 213 are provided vertically above the filtration section 210 , and a water guide pipe 215 and a filtration material 219 are provided within the filtration section 210 .

[0144] The switching valve 211 is a valve that switches the destination of the water flowing into the filtration unit 210 and the water discharged from the filtration unit 210 depending on the operating mode of the water purification device 201. The switching valve 211 is connected to each of the third water supply pipe 223c, the one end opening 213, the water conduit 215, the purified water discharge pipe 226, and the backwash discharge pipe 228. The switching valve 211 is connected to the control unit 203 so as to be able to communicate with it wirelessly or by wire, and the water destination is switched by a signal from the control unit 203.

[0145] The one-end opening 213 is connected to an end of the third water supply pipe 223 c in a water-conveying manner by switching the water supply destination using the switching valve 211 during the filtration mode, and is an opening for introducing the water to be treated flowing through the third water supply pipe 223 c into the filtration unit 210. Furthermore, the one-end opening 213 is connected to an end of the backwashing discharge pipe 228 in a water-conveying manner by switching the water supply destination using the switching valve 211 during the treated-water cleaning mode and the ozone-water cleaning mode, and is an opening for supplying the water in the filtration unit 210 to the backwashing discharge pipe 228. The one-end opening 213 corresponds to the other-end opening 217 described below, and is provided vertically above the other-end opening 217.

[0146] The filtering material 219 is a substance that captures substances to be treated, such as organic matter or bacteria, contained in the water to be treated, and may be, for example, activated carbon or filtering sand. In the third embodiment, both activated carbon and filtering sand are used as the filtering material 219. The filtering material 219 is provided below the filtering section 210, and a space exists above the filtering material 219 within the filtering section 210. Providing this space improves the cleaning efficiency in the cleaning mode.

[0147] The water conduit 215 is provided within the filtration unit 210 and is a pipe connecting the upper and lower parts of the filtration unit 210, with an other-end opening 217 provided at its lower end. When the filtration mode is being performed, the untreated water that has flowed into the filtration unit 210 is conveyed from the upper part to the lower part of the filtration unit 210 via the water conduit 215. When the untreated water cleaning mode and the ozone water cleaning mode are being performed, the water in the filtration unit 210 that has been used to clean the filtration material 219 in the filtration unit 210 is conveyed from the lower part to the upper part of the filtration unit 210 via the water conduit 215 and then sent out to the outside of the filtration unit 210.

[0148] The other end opening 217 is buried in the filtering material 219 and is provided vertically below the one end opening 213. The other end opening 217 is an opening that supplies water in the water conduit 215 into the filtration section 210 or supplies water in the filtration section 210 to the water conduit 215.

[0149] A lower portion of the water conduit 215, including the other end opening 217, is buried in the filtration material 219, while an upper portion of the water conduit 215 is not buried in the filtration material 219 and is connected to the switching valve 211. In other words, the water conduit 215 is a pipe that supplies water sent from the switching valve 211 to the filtration material 219 located in the lower portion of the filtration unit 210, or that supplies water in the filtration unit 210 to the switching valve 211 from below the filtration unit 210.

[0150] The concentration measurement unit 220 is provided on the path of the purified water discharge pipe 226 (described later) and is a device that measures the quality of the purified water produced by purification in the filtration unit 210. As the concentration measurement unit 220, for example, a COD meter (Chemical Oxygen Demand) can be used.

[0151] The purified water outlet 227 is an opening through which the treated water filtered by the water purifier 201 is taken out as purified water (treated water) to the outside of the water purifier 201. The purified water outlet 227 is provided in a housing constituting the water purifier 201, and is connected in communication with the purified water outlet pipe 226 described below.

[0152] Backwashing outlet 229 is an opening for discharging the untreated water or cleaning water used to clean filtration section 210 to the outside of water purifier 201. Backwashing outlet 229 is an opening provided in a housing that constitutes water purifier 201, and is connected in communication with backwashing outlet pipe 228. Note that the cleaning water is water that contains ozone gas.

[0153] (Flow paths and valves) The flow paths of the water purifier 201 are formed by an inlet pipe 222 , a first water supply pipe 223 a , a second water supply pipe 223 b , a third water supply pipe 223 c , a purified water discharge pipe 226 , and a backwash discharge pipe 228 .

[0154] The inlet pipe 222 is connected in communication with the inlet 221 and the upstream switching valve 205 , and is a pipe that supplies the water to be treated that has been taken into the water purifier 201 from the inlet 221 to the upstream switching valve 205 .

[0155] The upstream switching valve 205 is a valve that switches the water destination so that water is supplied from the inlet pipe 222 to either the first water supply pipe 223 a or the second water supply pipe 223 b. For example, a three-way motor-operated valve can be used as the upstream switching valve 205. The upstream switching valve 205 is connected to the control unit 203 wirelessly or via a wire so as to be able to communicate with the control unit 203, and the water destination is switched by a signal from the control unit 203.

[0156] The upstream switching valve 205 to the filtration section 210 is connected in communication with a first water supply pipe 223a, a second water supply pipe 223b, and a third water supply pipe 223c.

[0157] The first water supply pipe 223a is a pipe that connects the upstream switching valve 205 to a branch point 20B, which will be described later, and is used when the filtration mode and the untreated water washing mode are performed.

[0158] The second water supply pipe 223b is a pipe that connects the upstream switching valve 205 to a branch point 20B described later, and is used when the ozone water cleaning mode is executed. A constant flow valve 224, an ozone generator 207, and an ozone water generator 209 are provided on the second water supply pipe 223b.

[0159] The constant flow valve 224 is a valve that stabilizes the flow rate of the water to be treated that is fed to the ozone generation unit 207 at a constant flow rate during operation in the ozone water cleaning mode, and is connected in communication with the second water feed pipe 223b.

[0160] The third water supply pipe 223c is a pipe that connects the branch point 20B described later to one end opening 213 of the filtration section 210, and is used when the filtration mode, the treated water cleaning mode, and the ozone water cleaning mode are performed.

[0161] The downstream end of the inlet pipe 222, the upstream end of the first water supply pipe 223a, and the upstream end of the second water supply pipe 223b are connected to each other at a branch point 20A. An upstream switching valve 205 is provided on the branch point 20A.

[0162] The downstream end of the first water supply pipe 223a, the downstream end of the second water supply pipe 223b, and the upstream end of the third water supply pipe 223c are connected to each other at a branch point 20B. A three-way valve 225 is provided at the branch point 20B.

[0163] The three-way valve 225 is a valve that switches the water supply source so that water is supplied from either the first water supply pipe 223 a or the second water supply pipe 223 b to the third water supply pipe 223 c. The three-way valve 225 is connected to the control unit 203 wirelessly or via a wire so as to be able to communicate with the control unit 203, and the water supply destination is switched by a signal from the control unit 203.

[0164] The purified water discharge pipe 226 is connected in communication with the switching valve 211 and the purified water discharge port 227, and is a pipe that delivers the treated water from which organic matter, bacteria, etc. have been removed by the filtration unit 210 to the purified water discharge port 227. A concentration measurement unit 220 is provided on the path of the purified water discharge pipe 226.

[0165] The backwashing discharge pipe 228 is connected in communication with the switching valve 211 and the backwashing discharge port 229 , and is a pipe that delivers the untreated water or washing water used to wash the filtration section 210 to the backwashing discharge port 229 .

[0166] The control unit 203 controls switching of the flow path of the water to be treated flowing through the water purifier 201 during execution of each of the filtration mode, the water to be treated cleaning mode, and the ozone water cleaning mode. The specific flow path switching by the control unit 203 during execution of each mode will be described later. The hardware of the control unit 203 can be realized by elements or mechanical devices such as a computer's CPU (Central Processing Unit). The software is realized by a computer program or the like. Therefore, these functional blocks can be realized in various forms by combining hardware and software. More specifically, the control unit 203 is connected by wire or wirelessly to each of the ozone generator 207, the ozone water generator 209, the upstream switching valve 205, the constant flow valve 224, the three-way valve 225, the switching valve 211, and the concentration measurement unit 220, and controls the operation of each component. As shown in FIG. 10, the control unit 203 includes a storage unit 203b, a processing object comparison unit 203c, a determination unit 203d, a number counting unit 203e, and a cleaning execution unit 203f.

[0167] The memory unit 203b stores a reference value for the concentration of the target substance. The reference value for the concentration of the target substance can be set with reference to a water quality standard value, etc., appropriate for the target substance. For example, the water quality standard value for organic matter in Japan specifies that the amount of total organic carbon (TOC) is 3 mg / L or less. If this value is used as the reference value for the concentration of the target substance, purified water that complies with the water quality standard can be constantly provided. Note that although the reference value is referred to here as a reference value, even if the reference value is expressed as a range rather than a specific numerical value, the range can also be considered as the reference value.

[0168] The object comparison unit 203c compares the object concentration measured by the concentration measurement unit 220 with the reference value of the object concentration stored in the storage unit 203b, and transmits the comparison result to the determination unit 203d.

[0169] The determination unit 203d determines whether or not the purified water generated in the filtration mode is in a cleaning-required state based on whether the concentration of the substance to be treated in the purified water is equal to or greater than a reference value or less than the reference value. Specifically, when the concentration of the substance to be treated in the purified water is equal to or greater than a reference value, the determination unit 203d determines that the purified water is in a cleaning-required state in which cleaning of the filtration material 219 is necessary.

[0170] The counting unit 203e counts the number of times that the determining unit 203d has determined that the cleaning is necessary.

[0171] The cleaning execution unit 203f executes the cleaning mode when it is determined that the state requires cleaning based on information from the count counting unit 203e. Specifically, the cleaning execution unit 203f executes the treated water cleaning mode when the number of times that the state requires cleaning is determined to be less than a predetermined number, and executes the ozone water cleaning mode when the number of times that the state requires cleaning is determined to be greater than or equal to the predetermined number.

[0172] The above is the configuration of the water purifier 201.

[0173] Next, the operation of the water purifier 201 will be described.

[0174] First, the filtration mode and the cleaning mode of the water purifier 201 will be described with reference to Figures 11 and 12. Figure 11 is a flowchart showing the operation of the water purifier 201 according to the third embodiment of the present disclosure. Figure 12 is a schematic diagram of the water purifier 201 according to the third embodiment when the filtration mode is being executed.

[0175] The water purifier 201 operates in a filtration mode in which the water to be treated is filtered, and a cleaning mode in which the filter material 219 is cleaned. The cleaning mode includes a water to be treated cleaning mode in which the water to be treated is sent to the filtration unit 210 in a direction opposite to the direction of the raw water sent in the filtration mode, and an ozone water cleaning mode in which ozone water is sent to the filtration unit 210.

[0176] First, as shown in Fig. 11 , when water purifier 201 is activated, the filtration mode begins (step S001). In water purifier 201, in the filtration mode, control unit 203 controls the switching of the flow paths, so that upstream switching valve 205 communicates inlet pipe 222 with first water supply pipe 223a, three-way valve 225 communicates first water supply pipe 223a with third water supply pipe 223c, and switching valve 211 communicates third water supply pipe 223c with one-end opening 213. As a result, as shown by the arrows in Fig. 12 , the water to be treated, which contains impurities, flows from the outside of water purifier 201 into the inside of water purifier 201 and flows through inlet 221, inlet pipe 222, upstream switching valve 205, first water supply pipe 223a, three-way valve 225, third water supply pipe 223c, and switching valve 211 in this order. In other words, inlet pipe 222, first water supply pipe 223a, third water supply pipe 223c, and switching valve 211 form a purification flow path through which the water to be treated flows. After flowing through switching valve 211, the water to be treated flows into filtration section 210 from one end opening 213 and flows through filtration material 219 provided in filtration section 210. At this time, impurities in the water to be treated are adsorbed by filtration material 219, and the water to be treated is filtered. The purified water produced by filtering the water to be treated flows through purified water discharge pipe 226 and is sent out of water purifier 201 from purified water discharge outlet 227.

[0177] When the filtration mode is executed, the concentration measuring unit 220 measures the concentration of the target substance in the purified water that has been purified by the filtration unit 210 (step S002). The measured concentration information of the target substance is sent to the target substance comparing unit 203c.

[0178] The object comparison unit 203c compares the object concentration information received from the concentration measurement unit with the reference value of the object concentration stored in the memory unit 203b (step S003). If the comparison result shows that the object concentration is less than the reference value (NO in step S003), the filtration mode is continued. On the other hand, if the object concentration is equal to or greater than the reference value (YES in step S003), the determination unit 203d determines that the filtration medium 219 needs to be cleaned (step S004).

[0179] The counting unit 203e counts the number of times that it has been determined that the cleaning is necessary.

[0180] If the number of times that the cleaning-requiring state is determined to be less than the predetermined number of times (NO in step S005), the cleaning execution unit 203f ends the filtration mode (step S007a) and executes the untreated water cleaning mode (step S008a). Note that the predetermined number of times is an integer of 2 or more.

[0181] Here, the operation of the water purifier 201 when the untreated water washing mode is executed will be described with reference to Fig. 13. Fig. 13 is a schematic diagram of the untreated water washing mode executed according to the third embodiment.

[0182] In water purifier 201, in the treated water cleaning mode, control unit 203 controls the switching of the flow paths so that upstream switching valve 205 communicates inlet pipe 222 with first water supply pipe 223a, three-way valve 225 communicates first water supply pipe 223a with third water supply pipe 223c, and switching valve 211 communicates third water supply pipe 223c with water conduit 215. As a result, as shown by the arrows in Figure 13, the water to be treated flows from outside water purifier 201 into the water purifier 201 and flows through inlet 221, inlet pipe 222, upstream switching valve 205, first water supply pipe 223a, three-way valve 225, third water supply pipe 223c, switching valve 211, and water conduit 215 in this order. In other words, the inlet pipe 222, the first water supply pipe 223a, the third water supply pipe 223c, and the water conduit 215 form a cleaning flow path, through which the untreated water flows. The untreated water that flows through the water conduit 215 flows into the filtration unit 210 from the other end opening 217 of the filtration unit 210 and flows through the filtration material 219 provided in the filtration unit 210. In other words, the untreated water flows into the filtration unit 210 from the end opposite to the end when the filtration mode is being executed. The untreated water that flows in from the lower part of the filtration unit 210 passes through the pores of the filtration material 219 and between the pores and the pores, thereby removing the substances adsorbed between the pores and the pores. In this way, the untreated water that flows in from the lower part of the filtration unit 210 cleans the filtration material 219 inside the filtration unit 210, and is then sent to the upper part of the filtration unit 210 and then sent to the backwash discharge pipe 228 via the switching valve 211. Thereafter, the water to be treated flows through the backwashing discharge pipe 228 and is discharged from the backwashing discharge port 229 to the outside of the water purifier 201 .

[0183] 11 , if the execution time of the raw water cleaning mode is less than a certain time (e.g., 10 minutes) (NO in step S009a), the raw water cleaning mode continues to be executed. On the other hand, if the execution time of the raw water cleaning mode is equal to or longer than the certain time (YES in step S009a), the execution of the cleaning mode is terminated, and the filtration mode is executed or the system enters a standby state where the execution of the filtration mode is awaited.

[0184] On the other hand, if the number of times that the cleaning-needed state has been determined is equal to or greater than the predetermined number (YES in step S005), the number of times that the cleaning-needed state has been determined, which is counted by the counting unit 203e, is reset (step S006).Then, the cleaning execution unit 203f ends the filtration mode (step S007b) and executes the ozone water cleaning mode (step S008b).

[0185] Here, the operation of the water purifier 201 when the ozone water cleaning mode is executed will be described with reference to Fig. 14. Fig. 14 is a schematic diagram of the operation when the ozone water cleaning mode is executed according to the third embodiment.

[0186] In the ozone water cleaning mode, the control unit 203 controls the flow path switching of the water purifier 201, so that the upstream switching valve 205 connects the inlet pipe 222 to the second water supply pipe 223b, the three-way valve 225 connects the second water supply pipe 223b to the third water supply pipe 223c, and the switching valve 211 connects the third water supply pipe 223c to the water conduit 215. As a result, as shown by the arrows in Figure 14, the water to be treated flows from outside the water purifier 201 into the water purifier 201, passes through the inlet 221, the inlet pipe 222, the upstream switching valve 205, the second water supply pipe 223b, and the constant flow valve 224, and then flows into the ozone generator 207. The water to be treated that has flowed into the ozone generator 207 is electrolyzed by a pair of electrodes (an anode and a cathode) provided inside the ozone generator 207. This electrolysis generates ozone gas. The water to be treated containing ozone gas flows into the ozonated water generator 209, where the ozone gas dissolves in the water to produce cleaning water containing ozone. The cleaning water generated in the ozonated water generator 209 flows sequentially through the three-way valve 225, the third water supply pipe 223c, the switching valve 211, and the water conduit 215. The cleaning water that flows through the water conduit 215 flows into the filtration unit 210 from the other end opening 217 of the filtration unit 210 and flows through the filtration material 219 provided within the filtration unit 210. In other words, the cleaning water flows into the filtration unit 210 from the end opposite to that during the filtration mode. The flowing cleaning water passes through the pores of the filtration material 219 and between the pores and spaces of the filtration material 219, thereby removing the materials to be treated that are adsorbed between the pores and spaces of the filtration material 219 and sterilizing the ozone. In this way, the cleaning water that flows in from the lower part of the filtration section 210 cleans the filtering material 219 inside the filtration section 210, and is then sent to the upper part of the filtration section 210 and sent to the backwashing discharge pipe 228 via the switching valve 211. Thereafter, the cleaning water flows through the backwashing discharge pipe 228 and is drained from the backwashing discharge port 229 to the outside of the water purifier 201.

[0187] 11 , if the execution time of the ozone water cleaning mode is less than a certain time (e.g., 2 minutes) (NO in step S009b), the ozone water cleaning mode continues to be executed. On the other hand, if the execution time of the ozone water cleaning mode is equal to or longer than the certain time (YES in step S009b), the execution of the cleaning mode is terminated, and the filtration mode is executed or the system enters a standby state where the execution of the filtration mode is awaited.

[0188] As described above, the filtration mode, the untreated water cleaning mode, and the ozone water cleaning mode are repeatedly executed in the water purifier 201. In other words, the generation of purified water by the filtration unit 210 and the regeneration of the filtration unit 210 are repeatedly executed.

[0189] In addition, when the water purifier 201 is used daily in an ordinary household, the guideline for the frequency of running the ozone water cleaning mode is about once every few days to once a week to effectively suppress the growth of bacteria. For example, if it is determined that cleaning is necessary about once a day, the above-described condition can be met by setting the predetermined number of times to 3 to 7 times.

[0190] As described above, according to the water purifier 201 of the third embodiment, the following effects can be obtained.

[0191] (1) The water purification device 201 includes a filtration unit 210 that removes the treated substance from the treated water containing the treated substance using a filtration material 219 to produce purified water, a concentration measurement unit 220 that measures the concentration of the treated substance in the purified water, and a control unit 3 that controls the execution of a filtration mode that produces purified water from the treated water and a cleaning mode that cleans the filtration material 19. The cleaning water generating unit is an ozone water generating unit that generates ozone water by mixing ozone gas with water to be treated or purified water, and the control unit 203 further includes a memory unit 203b that stores a reference value for the concentration of the substance to be treated, a treatment object comparison unit 203c that compares the measured concentration of the substance to be treated in the purified water with the reference value for the concentration of the substance to be treated, a judgment unit 203d that judges that a cleaning-required state in which cleaning of the filtration material 219 is required exists when the concentration of the substance to be treated in the purified water generated in the filtration mode in which purified water is generated from the water to be treated is equal to or higher than the reference value for the concentration of the substance to be treated, and a cleaning execution unit 203f that executes the cleaning mode when the judgment unit 203d judges that a cleaning-required state exists.

[0192] With this configuration, the need for cleaning is determined based on the concentration of the substance to be treated contained in the purified water, so the filtration material 219 can be used continuously until it breaks through. Furthermore, because the filtration material 219 is cleaned based on the concentration of the substance to be treated in the purified water, the cleaning frequency of the filtration material 219 can be maintained at an appropriate level. This prevents the contamination of the substance to be treated into the purified water at levels above the standard value due to insufficient cleaning of the filtration material 219, and also prevents wear on the filtration material 219 due to unnecessary cleaning.

[0193] That is, in the water purifier 201, wear and damage to the filter material 219 due to filter material cleaning can be reduced, contributing to a longer life of the filter material 219 and a reduced replacement frequency.

[0194] (2) The water purifier 201 includes an ozone generator 207 that generates ozone gas by electrolysis of water, and an ozone water generator 209 that generates ozone water by mixing ozone gas with water to be treated or purified water, and the cleaning modes include a water to be treated cleaning mode in which water to be treated is sent to the filtration unit 210 in a direction opposite to the direction of raw water sent in the filtration mode, and an ozone water cleaning mode in which ozone water is sent to the filtration unit 210. The control unit 203 also includes a count counter 203e that counts the number of times a cleaning-required state is determined, and the cleaning execution unit 203f executes the water to be treated cleaning mode if the number of times a cleaning-required state is determined is less than a predetermined number, and executes the ozone water cleaning mode if the number of times a cleaning-required state is determined is equal to or greater than the predetermined number.

[0195] Because the action of ozone causes deterioration of the filtration material 219, if ozone water is used each time the raw water cleaning mode is executed, the lifespan of the filtration material 219 may be rapidly shortened. However, in the configuration according to the third embodiment of the present disclosure, the ozone water cleaning mode is not executed every time the cleaning mode is executed, so ozone water can be passed through at an optimal frequency. This can contribute to extending the lifespan of the filtration material 219 and reducing the replacement frequency while reducing bacterial growth on the filtration material 219.

[0196] (Embodiment 4) Water purifier 201b according to embodiment 4 of the present disclosure differs from embodiment 3 in that it changes the timing of execution of the cleaning mode based on the value of an element. Other configurations are the same as water purifier 201 according to embodiment 3. Below, the content already explained in embodiment 3 will be omitted as appropriate, and differences from embodiment 3 will be mainly explained. Specifically, the basic configuration of water purifier 201b is the same as the configuration described in embodiment 3, but the configuration of control unit 203 and the processing of control unit 203 are different. These points will be explained below.

[0197] The control unit 203x of the water purifier 201b will be described with reference to FIG.

[0198] Water purifier 201b includes control unit 203x. Control unit 203x controls switching of the flow path of the water to be treated circulating within water purifier 201b when the filtration mode, the water to be treated cleaning mode, and the ozone water cleaning mode are executed. Control unit 203x further includes element identification unit 203g, element storage unit 203h, element comparison unit 203i, and count change unit 203n in addition to memory unit 203b, object to be treated comparison unit 203c, determination unit 203d, count measurement unit 203e, and cleaning execution unit 203f of control unit 203 in embodiment 3.

[0199] The element identification unit 203g identifies the value of an element of the water to be treated. It is appropriate to set a factor that affects bacterial growth within the filtration material 219 as the element, such as water temperature. Methods for identifying the element value include, for example, a method in which a measurement unit is provided to measure the element and the element is measured automatically, a method in which an input unit is provided to input the element value and the user manually inputs the value, and a method in which information is obtained from a server or the like via a network. Furthermore, for example, if the element is water temperature, an identification method may be set according to the required element, such as a method in which the element is estimated from the ambient air temperature.

[0200] The element storage unit 203h stores the reference value of the element as the element reference value. For example, if water temperature is selected as the element, it is preferable to set the element reference value to 20°C to 30°C, which is a temperature at which bacteria easily grow.

[0201] The element comparison unit 203i compares the value of the element identified by the element identification unit 203g with the element reference value stored in the element storage unit 203h, and sends the comparison result to the count change unit 203n.

[0202] The count change unit 203n sets a first predetermined count or a second predetermined count to be used instead of the predetermined count based on the comparison result of the element comparison unit 203i and the predetermined count. Specifically, when water temperature is selected as the element, if the water temperature is higher than the element reference value, the count change unit 203n sets the first predetermined count to a count lower than the predetermined count. On the other hand, if the water temperature is lower than the element reference value, the count change unit 203n sets the second predetermined count to a count higher than the predetermined count. Information on the set first predetermined count or second predetermined count is transmitted to the count measurement unit 203e. When the count measured by the count measurement unit 203e reaches the first predetermined count or the second predetermined count, the ozone water cleaning mode is executed. Note that the first predetermined count is set within a range that does not result in 0.

[0203] The above is the configuration of the water purifier 201b.

[0204] Next, the operation of the water purifier 201b will be described.

[0205] The filtering mode and cleaning mode in the water purifier 201b will be described with reference to Fig. 16. Fig. 16 is a flowchart showing the operation of the water purifier 201b according to the fourth embodiment.

[0206] First, when the water purifier 201b is started, the filtration mode is initiated (step S201).

[0207] When the filtration mode is executed, the concentration measurement unit 220 measures the concentration of the target substance in the purified water produced by the filtration unit 210 (step S202). The measured concentration information of the target substance is sent to the target substance comparison unit 203c.

[0208] The object comparison unit 203c compares the object concentration information received from the concentration measurement unit with the reference value of the object concentration stored in the memory unit 203b (step S203). If the comparison result shows that the object concentration is less than the reference value (NO in step S203), the filtration mode is continued. On the other hand, if the object concentration is equal to or greater than the reference value (YES in step S203), the determination unit 203d determines that the filtration medium 219 needs to be cleaned (step S204).

[0209] The counting unit 203e counts the number of times that it has been determined that the cleaning is necessary.

[0210] The element specifying unit 203g specifies the element value of the water to be treated (step S211). As the element, it is appropriate to set a factor that affects bacterial growth in the filtration medium 219, such as water temperature.

[0211] The element storage unit 203h stores the reference value of the element as the element reference value. For example, if water temperature is selected as the element, it is preferable to set the element reference value to 20°C to 30°C, which is a temperature at which bacteria easily grow.

[0212] The element comparison unit 203i compares the value of the element identified by the element identification unit 203g with the element reference value stored in the element storage unit 203h (step S212).The comparison result is sent to the count change unit 203n.

[0213] The count change unit 203n sets a first predetermined count or a second predetermined count to be used instead of the predetermined count based on the comparison result of the element comparison unit 203i and the predetermined count (step S213). Specifically, when water temperature is selected as the element, if the water temperature is higher than the element reference value, the count change unit 203n sets the first predetermined count to a count less than the predetermined count. On the other hand, if the water temperature is lower than the element reference value, the count change unit 203n sets the second predetermined count to a count greater than the predetermined count. Information on the identified first predetermined count or second predetermined count is sent to the count measurement unit 203e. The first predetermined count is set within a range that does not result in 0.

[0214] If the number of times measured by the counting unit 203e is less than the specified first or second predetermined number of times (NO in step S205), the cleaning execution unit 203f ends the filtration mode (step S207a) and executes the untreated water cleaning mode (step S208a).If the execution time of the untreated water cleaning mode is less than a certain time (e.g., 10 minutes) (NO in step S209a), the untreated water cleaning mode continues to be executed.On the other hand, if the execution time of the untreated water cleaning mode is equal to or greater than the certain time (e.g., 10 minutes) (YES in step S209a), the execution of the cleaning mode is terminated and the filtration mode is executed or the unit enters a standby state where the filtration mode is waited for to be executed.

[0215] On the other hand, if the number of times counted by the count counting unit 203e is equal to or greater than the specified first predetermined number or second predetermined number (YES in step S205), the number of times that the cleaning-required state measured by the count counting unit 203e is determined to be in the state of being cleaned is reset (step S206). Then, the cleaning execution unit 203f ends the filtration mode (step S207b) and executes the ozone water cleaning mode (step S208b).

[0216] If the execution time of the ozone water cleaning mode is less than a certain time (e.g., 2 minutes) (NO in step S209b), the ozone water cleaning mode continues to be executed. On the other hand, if the execution time of the ozone water cleaning mode is equal to or greater than a certain time (e.g., 2 minutes) (YES in step S209b), the execution of the cleaning mode is terminated, and the filtration mode is executed or the system enters a standby state waiting for the execution of the filtration mode. Note that the ozone water cleaning mode is executed so that the total amount of ozone water flowing through the filtration unit 210 during the execution of the ozone water cleaning mode is equal to or greater than the volume of the filtration material 219.

[0217] As described above, the water purifier 201b repeatedly executes the filtration mode, the untreated water cleaning mode, and the ozone water cleaning mode. In other words, the generation of purified water by the filtration unit 210 and the regeneration of the filtration unit 210 are repeatedly executed.

[0218] As described above, according to the water purifier 201b of the fourth embodiment, the following effects can be obtained.

[0219] (3) The water purification device 201b is equipped with an element identification unit 203g that identifies the value of an element of the water to be treated, and the control unit 203x further includes an element memory unit 203h that stores the reference value of the element as the element reference value, and an element comparison unit 203i that compares the value of the identified element with the element reference value, and changes the timing of executing the cleaning mode depending on the comparison result between the value of the element and the element reference value when the filtration mode is executed.

[0220] With this configuration, the frequency of the ozone water cleaning mode can be changed depending on a specified factor, such as water temperature. Therefore, when the environment is favorable for bacterial growth on the filter material 219, ozone water is used frequently to disinfect the filter material 219. When the environment is unfavorable for bacterial growth on the filter material 219, the frequency of ozone water flow can be reduced to prevent deterioration of the filter material 219. As a specific example, when the factor in the water purifier 201b is the water temperature of the water being treated, and the water temperature is higher than the factor reference value, the ozone water cleaning mode is executed when a first predetermined number of times is reached, which is less than the predetermined number of times. This increases bacterial growth during seasons such as summer when the water temperature is high. However, by using the described operating method, the frequency of ozone cleaning can be increased to prevent bacterial growth. Furthermore, when the factor in the water purifier 201b is the water temperature of the water being treated, and the water temperature is lower than the factor reference value, the ozone water cleaning mode is not executed even when the predetermined number of times is reached, but is executed when a second predetermined number of times is reached, which is greater than the predetermined number of times. As a result, the proliferation of bacteria slows down during seasons when the water temperature is low, such as winter, so the frequency of ozone cleaning can be reduced and deterioration of the filter material 219 can be suppressed.

[0221] (Embodiment 5) A water purifier 201c according to embodiment 5 of the present disclosure differs from embodiment 3 in that it executes an ozone water cleaning mode before executing a filtration mode based on the amount of water flowing per predetermined period. Other configurations are the same as those of the water purifier 201 according to embodiment 3. Below, we will omit repetitive explanations of the content already explained in embodiment 3, and will mainly explain the differences from embodiment 3. Specifically, the basic device configuration of water purifier 201c is the same as the configuration described in embodiment 201, but the configuration of the control unit and the processing of the control unit are different. These points will be explained below.

[0222] The control unit 203y of the water purifier 201c will be described with reference to FIG.

[0223] Water purifier 201c includes control unit 203y. Control unit 203y controls switching of the flow path of the water to be treated circulating within water purifier 201c when the filtration mode, the water to be treated cleaning mode, and the ozone water cleaning mode are executed. Control unit 203y further includes water volume measurement unit 203j, water flow rate accumulation unit 203p, water flow rate memory unit 203k, and water flow rate comparison unit 203m, in addition to memory unit 203b, object to be treated comparison unit 203c, determination unit 203d, number counting unit 203e, and cleaning execution unit 203f of control unit 203 in embodiment 3.

[0224] The water volume measuring unit 203j measures the amount of water to be treated passing through the filtration unit 210. Information relating to the measured amount of passing water is sent to the water volume integrating unit 203p.

[0225] The water flow rate integrating unit 203p integrates the water flow rate measured by the water flow rate measuring unit 203j for each predetermined period (for example, several days to one week) and calculates it as an integrated water flow rate.

[0226] The water flow rate storage unit 203k stores the reference water flow rate for a predetermined period of time as the reference water flow rate. This predetermined period is the same as the predetermined period for the water flow rate integrating unit 203p. The reference water flow rate is preferably a water volume that does not replace all of the water stored in the water purifier 201c. For example, for a home water purifier, this value is approximately 0 L to 50 L.

[0227] The water flow rate comparison unit 203m compares the accumulated water flow rate calculated by the water flow rate accumulating unit 203p with the water flow reference value stored in the water flow rate storage unit 203k.

[0228] The above is the configuration of the water purifier 201c.

[0229] Next, the operation of the water purifier 201c will be described.

[0230] The filtering mode and the cleaning mode in the water purifier 201c will be described with reference to Fig. 18. Fig. 18 is a flowchart showing the operation of the water purifier 201c according to the fifth embodiment.

[0231] First, when the water purifier 201c is started, the water volume measuring unit 203j measures the volume of water to be treated flowing through the filtration unit 210 (step S311).

[0232] The measured water flow rate is integrated by the water flow rate integration unit 203p, and the water flow rate for a predetermined period is calculated as the integrated water flow rate (step S312).

[0233] The calculated cumulative water flow rate is compared by the water flow rate comparison unit 203m with the water flow reference value for the predetermined period stored in the water flow rate storage unit 203k (step S313). If the cumulative water flow rate for the predetermined period is equal to or greater than the water flow reference value (YES in step S313), the water purifier 201c enters a standby state in which it can execute the filtration mode (step S316).

[0234] On the other hand, if the cumulative amount of water passing per predetermined period is less than the water passing reference value (NO in step S313), the cleaning execution unit 203f starts the ozone water cleaning mode (step S314).

[0235] If the execution time of the ozone water cleaning mode is less than a certain time (e.g., 2 minutes) (NO in step S315), the ozone water cleaning mode continues. On the other hand, if the execution time of the ozone water cleaning mode is equal to or greater than a certain time (e.g., 2 minutes) (YES in step S315), the execution of the cleaning mode ends, and the water purifier 201c enters a standby state in which the filtration mode can be executed (step S316). Thereafter, the filtration mode is started as necessary. The flow after the start of the filtration mode is the same as the flow shown in embodiment 3, and therefore a description thereof will be omitted.

[0236] As described above, in the water purifier 201c, the ozone water cleaning mode is executed before the filtration mode is started, depending on the amount of water passing through per predetermined period.

[0237] As described above, according to the water purifier 201c according to the fifth embodiment of the present disclosure, the following effects can be obtained.

[0238] (4) The water purifier 201c includes a water volume measurement unit 203j that measures the amount of water passing through the filtration unit 210. The control unit 203y includes a water volume memory unit 203k that stores a reference value for the amount of water passing through a predetermined period as a reference water volume, and a water volume comparison unit 203m that compares the measured amount of water passing through with the reference water volume. If the amount of water passing through a predetermined period is less than the reference water volume, the ozone water cleaning mode is executed before the filtration mode is executed. If the water purifier 201c has not been used for a predetermined period and water has accumulated in the device, bacteria may grow in the filtration material 219 due to the accumulated water. However, by using the configuration according to the fifth embodiment, even if the water purifier 201c has not been used for a predetermined period, the ozone water cleaning mode is executed before the filtration mode is executed, thereby sterilizing the filtration material 219 with ozone. This reduces the possibility of bacteria being contained in the purified water, thereby producing clean purified water.

[0239] Furthermore, in many cases, during operation of the water purifier 201c, the total amount of untreated water or cleaning water passing through the filtration unit 210 in the untreated water cleaning mode and the ozone water cleaning mode is less than the amount of untreated water passing through the filtration unit 210 in the filtration mode. In other words, the amount of water passing through the filtration unit 210 when the filtration material 219 is being regenerated is less than the amount of water passing through the filtration unit 210 when purified water is produced. However, depending on the usage environment of the water purifier 201c, the amount of water passing through the filtration unit 210 in the filtration mode may be equal to or greater than the total amount of water passing through the filtration unit 210 in the untreated water cleaning mode and the ozone water cleaning mode.

[0240] The present disclosure has been described above based on the embodiments. These embodiments are merely examples, and it will be understood by those skilled in the art that various modifications are possible in the combination of the respective components or the respective treatment processes, and that such modifications are also within the scope of the present disclosure.

[0241] Although the fourth embodiment uses water temperature as a parameter, this is not limiting. For example, the amount of water flowing into the filtration unit 210 (flow rate) can be used as a parameter. In this case, a water meter capable of measuring the amount of water flowing through the filtration unit 210 is provided. For example, 1000 L, the average daily consumption in a typical household, is set as the parameter reference value, and the first or second predetermined number of times is set based on this parameter. Specifically, when the amount of water flowing into the filtration unit 210 per reference time period is greater than the parameter reference value, the first predetermined number of times is set, and the ozone water cleaning mode is performed less than the first predetermined number of times when a cleaning-required state is determined. In a water purifier, the greater the amount of water flowing through the filtration material 219, the greater the amount of material captured by the filtration material 219, which may promote the growth of bacteria that use the material as a nutrient source. However, by using the above method, the ozone water cleaning mode can be performed more frequently than usual when the amount of water flowing in is large, thereby suppressing the growth of bacteria that use the material as a nutrient source. On the other hand, if the amount of inflowing water per reference time is less than the element reference value, a second predetermined number of times is set, and the ozone water cleaning mode is performed a number of times greater than the predetermined number when a cleaning-requiring state is determined. In a water purifier, when the amount of inflowing water is low, the amount of treated material adhering to the filtration material 219 is small, slowing the growth of bacteria that use the treated material as a nutrient source. By using the above operating method, the number of times the ozone water cleaning mode is performed can be reduced in such cases, thereby preventing deterioration of the filtration material 219. Note that the actual values ​​for the first predetermined number and the second predetermined number of times can be set to different values ​​depending on whether the water temperature is used or the water flow rate is used. Note that the element reference value can also be set by measuring the frequency of use of the water purifier 201c and setting a certain frequency as the element reference value.

[0242] In the fifth embodiment, the water volume measuring unit 203j is configured within the control unit 203y, but this is not limiting, and for example, it may be provided outside the control unit 203 as a water meter.

[0243] The water purifier according to the present invention can be applied to a point-of-use (POU) water purifier or a point-of-entry (POE) water purifier.

[0244] REFERENCE SIGNS LIST 1 Water purifier 2 Water pipe 3 Control unit 5 Upstream switching valve 7 Ozone generator 9 Cleaning water generator 10 Filtration unit 11 Switching valve 13 One end opening 15 Water pipe 17 Other end opening 19 Filtering material 20 Measuring unit 21 Inlet 22 Inlet pipe 23a First water supply pipe 23b Second water supply pipe 23c Third water supply pipe 24 Constant flow valve 25 Three-way valve 26 Purified water discharge pipe 27 Purified water discharge outlet 28 Backwash discharge pipe 29 Backwash discharge outlet A Branch point B Branch point 101 Water purifier 102 Water pipe 103 Control unit 105 Upstream switching valve 107 Ozone generator 109 Ozone water generator 110 Filtration unit 111 Switching valve 113 One end opening 115 Water conveyance pipe 117 Other end opening 119 Filtering material 120 Measuring unit 121 Inlet 122 Inflow pipe 123a First water supply pipe 123b Second water supply pipe 123c Third water supply pipe 124 Constant flow valve 125 Three-way valve 126 Purified water discharge pipe 127 Purified water discharge outlet 128 Backwash discharge pipe 129 Backwash discharge outlet 130 Space 131 Space 10A Branch point 10B Branch point 201 Water purifier 201b Water purifier 201c Water purifier 202 Water pipe 203 Control unit 203x Control unit 203y Control unit 203b Memory unit 203c Treatment object comparison unit 203d Determination unit 203e Number measurement unit 203f Cleaning execution unit 203g Element identification unit 203h Element storage unit 203i Element comparison unit 203j Water volume measurement unit 203k Water flow volume storage unit 203m Water flow volume comparison unit 203n Number of times change unit 203p Water flow volume accumulation unit 205 Upstream switching valve 207 Ozone generation unit 209 Ozone water production unit 210 Filtration unit 211 Switching valve 213 One end opening 215 Water conveyance pipe 217 Other end opening 219 Filtering material 220 Concentration measurement unit 221 Inlet 222 Inlet pipe 223a First water supply pipe 223b Second water supply pipe 223c Third water supply pipe224 Constant flow valve 225 Three-way valve 226 Purified water discharge pipe 227 Purified water discharge outlet 228 Backwash discharge pipe 229 Backwash discharge outlet 20A Branch point 20B Branch point

Claims

1. A water purification device comprising: a filtration section that removes materials to be treated from water to be treated containing the materials using a filtration material to produce purified water; an ozone generation section that generates ozone gas by electrolysis of water; a cleaning water generation section that mixes the ozone gas with the water to be treated or the purified water to produce cleaning water; and a control section that supplies the cleaning water to the filtration section when cleaning the filtration material.

2. The water purification device according to claim 1, wherein the control unit supplies the water to be treated to the filtration unit before supplying the cleaning water.

3. The water purification device of claim 2, further comprising a purification flow path that supplies the water to be treated to a one-end opening provided on one end side of the filtration section, and a cleaning flow path that supplies the water to be treated to an other-end opening provided on the other end side corresponding to the one end side of the filtration section, wherein the control unit supplies the water to be treated from the one-end opening to the filtration section via the purification flow path when the filtration section produces purified water, and supplies the water to be treated from the other-end opening to the filtration section via the cleaning flow path when the filtration material is regenerated.

4. The water purification device of claim 1, further comprising a purification flow path that supplies the treated water to a one-end opening provided on one end side of the filtration section, and a cleaning flow path that supplies the treated water to an other-end opening provided on the other end side corresponding to the one end side of the filtration section, wherein the control unit supplies the treated water from the one-end opening to the filtration section via the purification flow path when the filtration section produces purified water, and supplies the cleaning water from the other-end opening to the filtration section via the cleaning flow path when the filtration material is regenerated.

5. A water purification device as described in claim 3 or claim 4, wherein the one end opening is provided vertically above the filtration section, and the other end opening is provided vertically below the one end opening.

6. The water purification device according to claim 1, wherein the control unit, when regenerating the filtration material, passes a volume of the cleaning water through the filtration unit that is at least equal to the volume of the filtration material.

7. The water purification device described in claim 1, wherein the cleaning water generating unit is an ozone water generating unit that generates ozone water by mixing the ozone gas with the water to be treated or the purified water, and the control unit controls the execution of a filtration mode in which the purified water is generated from the water to be treated and a cleaning mode in which the filtration material is cleaned, and before executing an ozone water cleaning mode that constitutes the cleaning mode and supplies the ozone water to the filtration unit, a filtration material expansion mode is executed for a certain period of time or more in which the water to be treated is supplied to the filtration unit in a direction opposite to the water supply direction of the water to be treated in the filtration mode to expand the compressed filtration material.

8. The water purification device described in claim 7, wherein the certain period of time is the shorter of the time from the start of the filtration material expansion mode until the porosity of the filtration section reaches the porosity before the start of the filtration mode, or the time until the porosity increases by 20% or more based on the porosity of the occupied part of the filtration material at the end of the filtration mode.

9. The water purification device according to claim 7, wherein the control unit, after executing the ozone water cleaning mode, executes a treated water cleaning mode that constitutes the cleaning mode and sends the treated water to the filtration unit.

10. The water purifier according to claim 7, wherein the flow rate of the ozone water in the ozone water cleaning mode is smaller than the flow rate of the water to be treated in the filtration material deployment mode.

11. The water purification device described in claim 10, wherein the control unit, after executing the ozone water cleaning mode, executes a treated water cleaning mode in which the treated water is sent to the filtration unit from the opposite direction, and the flow rate of the treated water in the treated water cleaning mode is greater than the flow rate of the ozone water in the ozone water cleaning mode.

12. A water purification device as described in claim 1, comprising: a concentration measuring unit for measuring the concentration of a substance to be treated in the purified water; the cleaning water generating unit is an ozone water generating unit that generates ozone water by mixing the ozone gas with the water to be treated or the purified water; the control unit comprising: a memory unit for storing a reference value of the concentration of the substance to be treated; a treatment object comparison unit for comparing the measured concentration of the substance to be treated in the purified water with the reference value of the concentration of the substance to be treated; a judgment unit for judging that a cleaning required state in which cleaning of the filtration material is required is reached when the concentration of the substance to be treated in the purified water generated in a filtration mode in which the purified water is generated from the water to be treated is equal to or greater than the reference value of the concentration of the substance to be treated; and a cleaning execution unit for executing a cleaning mode in which the filtration material is cleaned when the judgment unit judges that a cleaning required state is reached.

13. The water purification device described in claim 12, wherein the cleaning modes include a water-to-be-treated cleaning mode in which the water to be treated is fed to the filtration section in a direction opposite to the water feeding direction of the water to be treated in the filtration mode, and an ozone water cleaning mode in which the ozone water is fed to the filtration section, wherein the control unit further includes a count measuring unit that measures the number of times the state requiring cleaning is determined to be in a state requiring cleaning, and the cleaning execution unit executes the water-to-be-treated cleaning mode if the number of times the state requiring cleaning is determined to be in a state requiring cleaning is less than a predetermined number, and executes the ozone water cleaning mode if the number of times the state requiring cleaning is determined to be in a state requiring cleaning is equal to or greater than the predetermined number.

14. The control unit further comprises an element identification unit that identifies the value of an element of the water to be treated, an element memory unit that stores a reference value of the element as an element reference value, and an element comparison unit that compares the identified value of the element of the water to be treated with the element reference value, and the water purification device described in claim 13 changes the timing of execution of the cleaning mode depending on the comparison result between the value of the element of the water to be treated when the filtration mode is executed and the element reference value.

15. A water purification device as described in claim 14, wherein the element is the temperature of the water to be treated, and when the temperature of the water to be treated is greater than the element reference value and reaches a first predetermined number of times which is less than the predetermined number of times, the ozone water cleaning mode is executed.

16. The water purification device described in claim 14, wherein the element is the temperature of the water to be treated, and when the temperature of the water to be treated is lower than the element reference value, the ozone water cleaning mode is not executed even when the predetermined number of times is reached, and when a second predetermined number of times that is greater than the predetermined number of times is reached, the ozone water cleaning mode is executed.

17. A water purification device as described in claim 14, wherein the element is the inflow amount of water to be treated, and when the inflow amount of water to be treated per reference time is greater than the element reference value, and when it reaches a first specified number of times which is less than the specified number of times, the ozone water cleaning mode is executed.

18. The water purification device described in claim 14, wherein the element is the inflow amount of water to be treated, and when the inflow amount of water to be treated per reference time is smaller than the element reference value, the ozone water cleaning mode is not executed even when the specified number of times is reached, and when a second specified number of times that is greater than the specified number of times is reached, the ozone water cleaning mode is executed.

19. A water purification device as described in claim 13, further comprising a water volume measuring unit which measures the amount of water passing through the filtration unit, wherein the control unit comprises: a water volume memory unit which stores a reference value of the water volume passing through a specified period as a water volume reference value; and a water volume comparison unit which compares the measured water volume passing through with the water volume reference value, and wherein if the water volume passing through the specified period is less than the water volume reference value, the ozone water cleaning mode is executed before executing the filtration mode.

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