Water treatment device and water treatment method

Abstract

A water treatment device (100) is for sterilizing water (2) to be treated which is retained in a vessel (1), and is equipped with: an impact application part (4) for applying impact to the water (2) to be treated inside the vessel (1) to impart a dynamic pressure thereto and / or a pressurization part (8) for changing the static pressure of the water (2) to be treated inside the vessel (1) to a positive-pressure side; and a warming part (5) for warming the water (2) being treated inside the vessel (1), in accordance with a set warming temperature and a set holding time. The warming part (5) warms the water (2) being treated to which a dynamic pressure has been applied by the impact application part (4) and / or the water (2) being treated which is in the state of having the static pressure applied by the pressurization part (8).

Description

Water treatment device and water treatment method

[0001] The present disclosure relates to a water treatment device and a water treatment method.

[0002] For example, water stored in a container such as a water bottle may be contaminated by oral bacteria that are introduced during drinking. Furthermore, water stored in a container such as a barrel or a water tank may be contaminated by microorganisms that are introduced from the air. Known methods for sterilizing or removing microorganisms such as fungi present in water include methods that use chemicals or membranes with fine pores. However, methods that use chemicals or membranes require the re-addition or replacement of the chemicals or membranes, making management cumbersome.

[0003] To simplify management, a method for sterilizing a liquid in a container using cavitation is known (see, for example, Patent Document 1). Cavitation is a phenomenon in which localized low-pressure areas are generated in the liquid due to the movement of the liquid, resulting in the generation of bubbles. Patent Document 1 discloses that bubbles generated by cavitation expand and contract, collapse during the expansion and contraction process, and the shock waves generated when the bubbles collapse can sterilize the water to be treated. Patent Document 1 also discloses that a pressure detection unit is provided that detects the impact applied to the water to be treated as pressure, thereby making it possible to grasp the impact force applied to microorganisms in the water to be treated and determine whether the intended sterilization has been achieved. Therefore, it is possible to prevent microorganisms from remaining in the water to be treated due to insufficient impact force, and to steadily supply sterilized water.

[0004] International Publication No. 2022 / 185526

[0005] However, the water treatment device disclosed in Patent Document 1 had the problem that if there are many microorganisms resistant to impact force in the water to be treated, there is a risk that a small amount of those microorganisms will remain in the water to be treated, and further improvements are required.

[0006] The present disclosure discloses technology for solving the above-mentioned problems, and aims to provide a water treatment device and a water treatment method that can stably provide sterilized water even when a large number of microorganisms resistant to impact force are present in the water to be treated.

[0007] The water treatment device disclosed herein is a water treatment device that sterilizes water to be treated stored in a container, and includes at least one of an impact application unit that applies an impact to the water to be treated in the container to create dynamic pressure, and a pressure unit that changes the static pressure of the water to be treated in the container to the positive pressure side, and a heating unit that heats the water to be treated in the container according to a set heating temperature and holding time, and the heating unit heats at least one of the water to be treated after dynamic pressure has been applied by the impact application unit and the water to be treated in a state where static pressure has been applied by the pressure unit. The water treatment method disclosed herein is a water treatment method for sterilizing water to be treated stored in a container, and includes a pressurizing step of performing at least one of applying an impact to the water to be treated in the container to create dynamic pressure and changing the static pressure of the water to be treated in the container to the positive pressure side, and a heating step of heating the water to be treated in the container according to a set heating temperature and holding time, wherein the heating step heats at least one of the water to be treated after the dynamic pressure has been applied by applying the impact and the water to be treated in a state where the static pressure has been changed to the positive pressure side.

[0008] According to the water treatment device and water treatment method of the present disclosure, sterilized water can be stably provided even when a large number of microorganisms resistant to impact force are present in the water to be treated.

[0009] FIG. 1 is a configuration diagram showing the configuration of a water treatment device according to embodiment 1. FIG. 2 is a configuration diagram showing the treatment flow of a water treatment device according to embodiment 1. FIG. 3 is a configuration diagram showing the configuration of a water treatment device according to embodiment 2. FIG. 4 is a configuration diagram showing the treatment flow of a water treatment device according to embodiment 2. FIG. 5 is a configuration diagram showing the configuration of a water treatment device according to embodiment 3. FIG. 6 is a configuration diagram showing the configuration of a storage type hot water supply device according to embodiment 4. FIG. 7 is a diagram showing the operation of a boiling operation of a storage type hot water supply device according to embodiment 4. FIG. 8 is a diagram showing the operation of an equalizing operation of a storage type hot water supply device according to embodiment 4. FIG. 9 is a diagram showing an example of the hardware configuration of a control device of a water treatment device according to an embodiment.

[0010] Embodiment 1. Hereinafter, a description will be given of a water treatment device and a water treatment method according to embodiment 1. Note that the embodiments described below are merely examples, and the present disclosure is not limited to these embodiments.

[0011] A water treatment device according to a first embodiment of the present disclosure will be described. FIG. 1 is a schematic diagram showing the configuration of a water treatment device according to the first embodiment. As shown in FIG. 1, a water treatment device 100 sterilizes water to be treated 2 stored in a container 1. The container 1 can be made of any material, but since dynamic pressure or static pressure is applied to the container 1, it is desirable that the container 1 be made of a material that can withstand a certain amount of pressure. An opening 1a is formed at one end of the container 1. In the example shown in FIG. 1, the opening 1a is formed at the top end of the container 1 in the vertical direction (direction of arrow Z).

[0012] The water treatment device 100 includes a lid 3 that seals the opening 1a of the container 1, an impact application unit 4 that applies an impact to the water to be treated 2, a heating unit 5 that heats the water to be treated 2, a control device 6 that controls the heating unit 5, a temperature sensor 7 that measures the temperature of the water to be treated 2, and a pressurizing unit 8 that pressurizes the water to be treated 2. The lid 3 is detachably attached to the container 1. The impact application unit 4 is installed on the lid 3 so that the oscillation surface 4a on the underside of the impact application unit 4 contacts the upper surface of the lid 3. In addition, the container 1 is provided with a water supply pipe 101 that supplies the water to be treated 2, and the pressurizing unit 8 is provided with a discharge pipe 102 that discharges the water to be treated 2 after treatment.

[0013] In the first embodiment, an impact is applied to the water to be treated 2 supplied from the water supply pipe 101 to the container 1 via the impact application unit 4, which is installed on the lid 3 so that the oscillation surface 4a contacts the upper surface of the lid 3. This impact is then transmitted to the water to be treated 2 via the lid 3. After the impact is applied by the impact application unit 4, the water to be treated 2 is further heated by the heating unit 5, thereby sterilizing the water by heat treatment. The heating unit 5 and the temperature sensor 7 are connected to the control unit 6 via a signal line. The control unit 6 controls the heating temperature and holding time of the heating unit 5 based on the measurement value of the temperature sensor 7, and adjusts the output and operating time of the heating unit 5 to achieve a preset heating temperature and holding time. By applying an impact by the impact application unit 4 and then performing heat treatment by the heating unit 5, damage to the cell walls or cell membranes of even impact-resistant microorganisms can be inflicted during the initial impact application, thereby reducing the heating temperature and holding time required for sterilization compared to when no impact is applied.

[0014] Furthermore, instead of applying an impact by the impact application unit 4, the container 1 can be pressurized by the pressurizing unit 8, the hydrostatic pressure inside the container 1 can be changed to the positive pressure side, and the pressurized water to be treated 2 can be subjected to heat treatment by the heating unit 5. This also improves the heat treatment effect by damaging the cell walls or cell membranes, and reduces the heating temperature and holding time required for sterilization compared to when heat treatment is performed under atmospheric pressure without pressurization. The impact application by the impact application unit 4 and the pressurization by the pressurizing unit 8 may be combined, and the container 1 may be pressurized by the pressurizing unit 8, and the impact application by the impact application unit 4 may be applied to the water to be treated 2 in a state in which the hydrostatic pressure inside the container 1 has been changed to the positive pressure side.

[0015] The lid 3 seals the container 1. While the lid 3 can be made of any material, it is preferable that the lid 3 be made of a material that does not reflect the impact between the lid 3 and the water to be treated 2, since the impact from the impact applicator 4 is transmitted to the water to be treated 2 via the lid 3. To prevent the impact from the impact applicator 4 from reflecting at the interface between the lid 3 and the water to be treated 2, it is desirable that the acoustic impedance, which is the product of density and sound speed, be equal between the water to be treated 2 and the lid 3. Acoustic impedance represents the ease with which sound propagates, and each object has its own unique acoustic impedance. Impact is reflected when the difference in acoustic impedance between the two media (the lid 3 and the water to be treated 2) is large, and transmitted when the difference in acoustic impedance is small. Materials with an acoustic impedance similar to that of water and a certain degree of elasticity for sealing the container 1 include, for example, polycarbonate resin and ρC rubber (ρC is the acoustic impedance, ρ is the density of the medium, and C is the sound speed in the medium), which has the same transmittance to ultrasound as water.

[0016] The impact applying unit 4 can be configured to apply an impact electrically or mechanically. For example, the impact applying unit 4 is configured with a vibrator that vibrates due to electrical conduction. Note that the configuration of the impact applying unit 4 is not particularly limited to this. Furthermore, the impact applying unit 4 can apply an impact to the water 2 to be treated intermittently, discontinuously, or continuously.

[0017] The heating section 5 is not particularly limited as long as it can increase the temperature of the water 2 to be treated, and a general heater, heat exchanger, or the like can be used.

[0018] The pressurizing unit 8 is not particularly limited as long as it can change the hydrostatic pressure of the water 2 to be treated in the vessel 1 to the positive pressure side, and a general pressurizing pump, a pressurizing valve, or the like can be used.

[0019] The dynamic pressure applied by the impact application unit 4 is preferably 1 MPa or more and 10 MPa or less, and more preferably 2 MPa or more and 5 MPa or less. If the dynamic pressure is lower than the above range, there is a risk that microorganisms will not be sterilized. On the other hand, if the dynamic pressure is higher than the above range, the power required for sterilization will increase, and the durability required for the container 1 will increase, which may result in higher costs. Note that the dynamic pressure is preferably applied as a pulse wave on the order of μs.

[0020] The hydrostatic pressure varied by the pressure unit 8 is preferably 0.1 MPa or more and 1 MPa or less, and more preferably 0.2 MPa or more and 0.4 MPa or less. If the hydrostatic pressure is lower than the above range, there is a risk that the cell wall or cell membrane will be damaged and the heat treatment effect will not be improved. Furthermore, if the hydrostatic pressure is higher than the above range, there is a risk that the power required for sterilization will increase and the durability required for the container 1 will increase, resulting in higher costs.

[0021] The heating temperature by the heating unit 5 is not particularly limited as long as it can sterilize the microorganisms in the water to be treated 2, but is preferably 40°C or higher and 80°C or lower, and more preferably 50°C or higher and 60°C or lower. If the temperature is lower than the above range, there is a risk that the microorganisms cannot be sterilized, and if the temperature is higher than the above range, there is a risk that the power required for sterilization will increase excessively, resulting in a decrease in treatment efficiency. In addition, the retention time by the heating unit 5 is also not particularly limited as long as it can sterilize the microorganisms in the water to be treated 2, but is preferably 15 minutes or higher and 60 minutes or lower, and more preferably 20 minutes or higher and 40 minutes or lower. If the temperature is lower than the above range, there is a risk that the microorganisms cannot be sterilized, and if the temperature is higher than the above range, there is a risk that the power required for sterilization will increase excessively, resulting in a decrease in treatment efficiency.

[0022] As described above, the water treatment device 100 of embodiment 1 is equipped with at least one of an impact application unit 4 that applies an impact to the water to be treated 2 to create dynamic pressure, or a pressure application unit 8 that changes the hydrostatic pressure of the water to be treated 2 to the positive pressure side, a heating unit 5 that heat-treats the water to be treated 2, and a control device 6 that controls the heating temperature and retention time by the heating unit 5 based on the measurement value of the temperature sensor 7, and adjusts the output and operating time of the heating unit 5 so that the heating temperature and retention time are set to a predetermined value.Therefore, compared to heat treatment under atmospheric pressure without applying an impact, the heating temperature and retention time required for sterilization can be reduced, and sterilized water can be stably provided even if there are many microorganisms resistant to impact force in the water to be treated.

[0023] Fig. 2 is a flowchart showing the treatment process of the water treatment device according to embodiment 1. In Fig. 2, step S101 is a water supply step, step S102 is an impact application step or pressurization step, step S103 is a heating step, and step S104 is a drainage step.

[0024] First, in step S101, the water to be treated 2 is supplied to the container 1 from the water supply pipe 101. This step S101 is an example of a water supply step.

[0025] Next, in step S102, the impact applying unit 4 propagates an impact to the water 2 to be treated via the lid 3. Alternatively, the pressurizing unit 8 changes the hydrostatic pressure in the container 1 to the positive pressure side. Step S102 is an example of a pressurizing step.

[0026] Next, in step S103, after the pressurization step in step S102, the heating unit 5 performs heat treatment on the water 2 to be treated at a heating temperature and for a holding time that are preset in the control device 6. This step S103 is an example of a heating step.

[0027] Finally, in step S104, the water to be treated 2 is discharged from the container 1 through the discharge pipe 102. This step S104 is an example of a drainage step.

[0028] As described above, by heat-treating the water to be treated 2 after applying an impact to the water to be treated 2 or after the hydrostatic pressure of the water to be treated 2 has changed to the positive pressure side, the heating temperature and holding time required for sterilization can be reduced compared to when heat-treating the water to be treated under atmospheric pressure without applying an impact, and sterilized water can be provided stably even when there are many microorganisms resistant to impact forces in the water to be treated.

[0029] As described above, the water treatment device of embodiment 1 is a water treatment device that sterilizes water to be treated stored in a container, and includes at least one of an impact application unit that applies an impact to the water to be treated in the container to give it dynamic pressure, and a pressurization unit that changes the static pressure of the water to be treated in the container to the positive pressure side, and a heating unit that heats the water to be treated in the container according to a set heating temperature and holding time, and the heating unit heats at least one of the water to be treated after dynamic pressure has been applied by the impact application unit and the water to be treated in a state where static pressure has been applied by the pressurization unit. Furthermore, the water treatment method of the first embodiment is a water treatment method for sterilizing water to be treated stored in a container, comprising: a pressurizing step of performing at least one of applying an impact to the water to be treated in the container to apply dynamic pressure and shifting the static pressure of the water to be treated in the container to a positive pressure; and a heating step of heating the water to be treated in the container according to a set heating temperature and holding time, wherein the heating step heats at least one of the water to be treated that has been subjected to dynamic pressure by applying the impact and the water to be treated that has been subjected to static pressure shifted to the positive pressure. This makes it possible to stably provide sterilized water even when there are many microorganisms resistant to impact force in the water to be treated.

[0030] The water treatment device of the first embodiment also includes a temperature sensor that measures the temperature of the water to be treated in the container, and a control device that adjusts the heating temperature and retention time of the heating unit based on the measurement value of the temperature sensor. The water treatment method of the first embodiment also includes a temperature measurement step that measures the temperature of the water to be treated in the container, and adjusts the heating temperature and retention time of the heating step based on the measurement value of the temperature measurement step. This makes it possible to consistently provide sterilized water even when the water to be treated contains a large number of microorganisms that are resistant to impact force.

[0031] 3 is a schematic diagram showing the configuration of a water treatment device according to embodiment 2. The water treatment device 100A of embodiment 2 differs from embodiment 1 in that a pressure sensor 9 is provided inside the container 1, and the control device 6 is connected to the pressure sensor 9, the impact application unit 4, and the pressurization unit 8 by signal lines. However, the other configurations are the same as those of embodiment 1.

[0032] In the water treatment device according to the second embodiment, the pressure sensor 9 allows the impact force applied to the water to be treated 2 by the impact application unit 4 to be converted into a voltage value and measured. Furthermore, the hydrostatic pressure of the water to be treated 2, which has been changed by the pressurization unit 8, can be converted into a voltage value and measured. These measured values ​​are input to the control device 6, which sets the heating temperature and holding time for the heat treatment by the heating unit 5 according to the input impact force or hydrostatic pressure, and adjusts the output and operating time of the heating unit 5 based on the set heating temperature and holding time. This makes it possible to reduce the heating temperature and holding time required for sterilization compared to heat treatment under atmospheric pressure without applying an impact, and more reliably provide sterilized water even when the water to be treated contains many microorganisms resistant to impact force.

[0033] In the case of heat treatment under atmospheric pressure without applying impact or hydrostatic pressure, the heating temperature and holding time required to obtain the target sterilization rate are determined, and these are set in the control device 6 as the standard heating temperature and standard holding time. This enables the control device 6 to set the heating temperature and holding time in the heat treatment by the heating unit 5 to values ​​smaller than the standard heating temperature and standard holding time, depending on the input impact force or hydrostatic pressure.

[0034] The settings of the heating temperature and holding time relative to the impact force or hydrostatic pressure vary depending on the type or properties of the water to be treated 2, so it is desirable to obtain data in advance by conducting laboratory tests (tests conducted in a laboratory using specialized measuring equipment, etc.). The heating temperature and holding time required when the impact force is varied can be obtained from data on the sterilization rate of the water to be treated 2. The sterilization rate data can be obtained using a known technique such as a viable cell count measurement method using CFUs (colony forming units). Similarly, the heating temperature and holding time required when the hydrostatic pressure is varied can be obtained from data on the sterilization rate of the water to be treated 2.

[0035] The pressure sensor 9 may be a commercially available product, and is configured, for example, by a piezoelectric element that generates a voltage when force (pressure) is applied, a so-called piezo element, or the like.

[0036] Figure 4 is a flowchart showing the treatment process of the water treatment device according to embodiment 2. In Figure 4, step S201 is a water supply step, step S202 is an impact application step or pressurization step, step S203 is a pressure measurement step, step S204 is a heating condition setting step, step S205 is a heating step, and step S206 is a drainage step.

[0037] First, in step S201, the water to be treated 2 is supplied to the container 1 from the water supply pipe 101. This step S201 is an example of a water supply step.

[0038] Next, in step S202, the impact applying unit 4 propagates an impact to the water 2 to be treated via the lid 3. Alternatively, the pressurizing unit 8 changes the hydrostatic pressure in the container 1 to the positive pressure side. Step S202 is an example of a pressurizing step.

[0039] Next, in step S203, the impact force applied to the water 2 to be treated in the pressurizing step of step S202 or the hydrostatic pressure that has fluctuated to the positive pressure side is converted into a voltage value, which is measured and input to the control device 6. Step S203 is an example of a pressure measurement step.

[0040] Next, in step S204, the control device 6 sets the heating temperature and holding time in the heat treatment by the heating unit 5 to values ​​smaller than the standard heating temperature and standard holding time in accordance with the input impact force or hydrostatic pressure. Step S204 is an example of a heating condition setting step.

[0041] Next, in step S205, after the heating condition setting step in step S204, the heating unit 5 performs heat treatment on the water 2 to be treated at the set heating temperature and for the set holding time. This step S205 is an example of a heating step.

[0042] Finally, in step S206, the water to be treated 2 is discharged from the container 1 through the discharge pipe 102. This step S206 is an example of a drainage step.

[0043] As described above, after applying an impact to the water to be treated 2 or after the hydrostatic pressure of the water to be treated 2 changes to the positive pressure side, the applied impact force or the hydrostatic pressure that has changed to the positive pressure side is measured, and heat treatment is performed under heating conditions based on this measured value.This makes it possible to reduce the heating temperature and holding time required for sterilization compared to heat treatment under atmospheric pressure without applying an impact, and more consistently achieve the effect of providing sterilized water even when there are many microorganisms resistant to impact force in the water to be treated.

[0044] As described above, in the water treatment device of the second embodiment, the control device adjusts at least one of the heating temperature and the holding time to a value smaller than the standard heating temperature or standard holding time required to sterilize the water to be treated at atmospheric pressure without applying dynamic pressure from the impact application unit and static pressure from the pressurization unit. Furthermore, in the water treatment method of the second embodiment, in the heating step, the control device adjusts at least one of the heating temperature and the holding time to a value smaller than the standard heating temperature or standard holding time required to sterilize the water to be treated at atmospheric pressure without applying dynamic pressure from the impact and static pressure shifted to the positive pressure side. This makes it possible to consistently provide water sterilized at a heating temperature or holding time shorter than the standard heating temperature or standard holding time, even when a large number of microorganisms resistant to impact force are present in the water to be treated.

[0045] The water treatment device of the second embodiment also includes a pressure sensor that measures at least one of the dynamic pressure generated by the impact application unit and the static pressure generated by the pressurization unit, and the control device adjusts at least one of the heating temperature and the holding time generated by the heating unit based on the measurement value of the pressure sensor. The water treatment method of the second embodiment also includes a pressure measurement step that measures at least one of the dynamic pressure generated by the impact and the static pressure fluctuated to the positive pressure side, and in the heating step, adjusts at least one of the heating temperature and the holding time based on the measurement value of the pressure measurement step. This makes it possible to more consistently provide sterilized water even when a large number of microorganisms resistant to impact force are present in the water to be treated.

[0046] Embodiment 3. Figure 5 is a schematic diagram showing the configuration of a water treatment device according to embodiment 3. The water treatment device 100B of embodiment 3 differs from embodiment 2 in that it includes an agent concentration measurement unit 10 that measures the concentration of an agent that reduces the activity of microorganisms, such as an oxidizing agent or an antibacterial agent, inside the container 1, and an agent addition unit 11 that adds the agent to the water to be treated 2, and in that the control device 6 is connected to the agent concentration measurement unit 10 and the agent addition unit 11 by signal lines. The rest of the configuration is the same as that of embodiment 2.

[0047] In the water treatment device 100B according to the third embodiment, an agent such as an oxidizing agent or an antibacterial agent is added to the water to be treated 2 by the agent addition unit 11, and then the concentration of the agent in the water to be treated 2 is measured by the agent concentration measurement unit 10 and input to the control device 6. Then, the control device 6 sets the impact force to be applied to the water to be treated 2 by the impact application unit 4 or the hydrostatic pressure of the water to be treated 2 to be varied by the pressurization unit 8, based on the input concentration of the agent. Based on the set impact force, the control device 6 adjusts the output, such as the amount of current flowing through the impact application unit 4, to apply an impact to the water to be treated 2. Alternatively, based on the set hydrostatic pressure, the control device 6 adjusts the pump output of the pressurization unit 8 or the amount of pressurization, such as the opening of the pressurization valve, to vary the hydrostatic pressure of the water to be treated 2 to a positive pressure. The actual measured value of the impact force or hydrostatic pressure is obtained by the pressure sensor 9 and input to the control device 6. The control device 6 then sets the heating temperature and holding time for the heat treatment by the heating unit 5 according to the input impact force or hydrostatic pressure, and adjusts the output and operating time of the heating unit 5 based on the set heating temperature and holding time.

[0048] The use of chemicals such as oxidizing agents or antibacterial agents makes it easier to damage the cell walls or cell membranes of microorganisms by applying impact from the impact applying unit 4 or applying pressure from the pressure applying unit 8. Therefore, compared to heat treatment under atmospheric pressure without applying impact, the heating temperature and holding time required for sterilization can be reduced, and sterilized water can be stably provided according to the type or properties of the water to be treated 2, even if there are many microorganisms resistant to impact force in the water to be treated.

[0049] If the water to be treated 2 is tap water or the like that already contains an oxidizing agent such as residual chlorine, the above-mentioned effect can be obtained even if there is no need to add a new oxidizing agent or antibacterial agent.

[0050] The impact force or hydrostatic pressure setting relative to the chemical concentration measured by the chemical concentration measurement unit 10 varies depending on the type or properties of the water to be treated 2, so it is desirable to obtain data in advance by conducting laboratory tests, etc. After obtaining correlation data between the impact force or hydrostatic pressure and the sterilization rate when no chemical is added to the water to be treated 2 by the chemical addition unit 11, the concentration of the chemical to be added is varied and the correlation data between the impact force or hydrostatic pressure and the sterilization rate is verified, thereby making it possible to calculate the relational equation for the impact force or hydrostatic pressure to be set by the control device 6 according to the chemical concentration. Compared to when no chemical is added, when a chemical is added, the impact force or hydrostatic pressure required to obtain the same sterilization rate can be reduced.

[0051] As described above, the water treatment device of the third embodiment includes a chemical agent measurement sensor that measures the concentration of an oxidant or antibacterial agent in the water to be treated. The control device determines a pressure set value for at least one of the dynamic pressure and the static pressure based on the measurement value of the chemical agent measurement sensor, and adjusts the output of at least one of the impact application unit and the pressurization unit so that the measurement value of the pressure sensor matches the pressure set value. The water treatment method of the third embodiment also includes a chemical agent measurement step that measures the concentration of an oxidant or antibacterial agent in the water to be treated. The pressurization step determines a pressure set value for at least one of the dynamic pressure and the static pressure based on the measurement value of the chemical agent measurement step, and adjusts at least one of the dynamic pressure and the static pressure so that the measurement value of the pressure measurement step matches the pressure set value. This achieves the effect of consistently providing sterilized water according to the type or properties of the water to be treated, even when a large number of microorganisms resistant to impact force are present in the water to be treated.

[0052] Furthermore, the water treatment device of the third embodiment includes an agent addition unit that adds an oxidant or an antibacterial agent to the water to be treated, and an agent measurement sensor that measures the concentration of the oxidant or antibacterial agent in the water to be treated, wherein the control device determines a pressure set value for at least one of the dynamic pressure or the static pressure based on the measurement value of the agent measurement sensor, and adjusts the output of at least one of the impact application unit and the pressurization unit so that the measurement value of the pressure sensor becomes the pressure set value. Furthermore, the water treatment method of the third embodiment includes an agent addition step that adds an oxidant or an antibacterial agent to the water to be treated, and an agent measurement step that measures the concentration of the oxidant or antibacterial agent in the water to be treated, wherein the pressurization step determines a pressure set value for at least one of the dynamic pressure or the static pressure based on the measurement value of the agent measurement step, and adjusts at least one of the dynamic pressure and the static pressure so that the measurement value of the pressure measurement step becomes the pressure set value. This has the effect of making it possible to stably provide sterilized water according to the type or properties of the water to be treated, even if there are many microorganisms resistant to impact force in the water to be treated.

[0053] Embodiment 4. Embodiment 4 is an embodiment in which the water treatment device of Embodiments 1 to 3, particularly the water treatment device of Embodiment 1, is applied to a storage-type hot water supply system, and will be described below. Figure 6 is a configuration diagram showing the configuration of a storage-type hot water supply system as a water treatment device according to Embodiment 4, Figure 7 is a diagram showing the operation of the boiling operation of the storage-type hot water supply system according to Embodiment 4, and Figure 8 is a diagram showing the operation of the equalizing operation of the storage-type hot water supply system according to Embodiment 4.

[0054] As shown in Figure 6, the hot water storage type hot water supply apparatus 201 of the fourth embodiment is roughly composed of a hot water storage unit 300 and a heat pump unit 400. In addition, a bathtub 500 is connected to the hot water storage type hot water supply apparatus 201.

[0055] The hot water storage type hot water heater 201 stores hot water heated by a heat pump unit 400, which is a heating means, in a hot water storage tank 301 in a hot water storage unit 300. The heat pump unit 400 includes, for example, a compressor, a water-refrigerant heat exchanger, an expansion valve, and an air heat exchanger. These components are connected in a ring shape to form a refrigeration cycle circuit for circulating the refrigerant.

[0056] The hot water storage unit 300 mainly includes a hot water storage tank 301, a circulation pump 302, and a four-way valve 303. During heating operation, the circulation pump 302 supplies hot water taken from the bottom (hereinafter referred to as the bottom) or the top (hereinafter referred to as the top) of the hot water storage tank 301 to the heat pump unit 400, and returns the hot water heated by the heat pump unit 400 to the top of the hot water storage tank 301. As will be described later, during equalization operation (an operation for equalizing the temperature of the hot water in the hot water storage tank 301), the circulation pump 302 returns the hot water taken from the top of the hot water storage tank 301 to the bottom of the hot water storage tank 301 via the heat pump unit 400.

[0057] Four-way valve 303 has four water inlet / outlet ports a to d. Water inlet / outlet port a is connected to hot water storage tank 301 via piping 311. Water inlet / outlet port b is connected to heat pump unit 400 via piping 312 and circulation pump 302. Water inlet / outlet port c is connected to heat pump unit 400 via piping 313. And water inlet / outlet port d is connected to the top of hot water storage tank 301 via piping 314.

[0058] In addition, tap water is supplied to the hot water storage unit 300 through a water supply terminal 321. The water supply terminal 321 is connected to the inlets of mixing valves 322 and 323 via pipe 315. Pipe 315 branches and is connected to the hot water storage tank 301 via pipe 315a and a pressure reducing valve 325. The pressure reducing valve 325 can be set to any value between 0.1 MPa and 0.4 MPa, but is set to 0.28 MPa here. The inlets of mixing valves 322 and 323 are connected to the hot water storage tank 301 and the water inlet / outlet port d of the four-way valve 303 via pipe 314. The outlet of mixing valve 322 is connected to the hot water supply terminal 324 via pipe 316. A thermistor 331 for detecting water temperature is installed along pipe 316. The outlet of mixing valve 323 is connected to the bathtub 500 via pipe 317. A thermistor 332 for detecting the water temperature is installed midway along the pipe 317, and thermistors 333, 334, and 335 are installed from the top to the bottom of the hot water storage tank 301.

[0059] In the hot water storage type hot water supply device 201 of the fourth embodiment shown in Figure 6, the hot water storage tank 301 corresponds to the container 1 of the first embodiment (Figure 1), the water supply end 321, the pipe 315, the pipe 315a, and the pressure reducing valve 325 correspond to the pressurizing unit 8 of the first embodiment (Figure 1), the heat pump unit 400, the circulation pump 302, the four-way valve 303, and the pipes 311 to 314 correspond to the heating unit 5 of the first embodiment (Figure 1), and thermistors 333 to 335 correspond to the temperature sensor 7 of the first embodiment (Figure 1). Note that a control device for controlling each component is omitted.

[0060] <Heating Operation> The heating operation of the hot water storage type hot water heater 201 of the fourth embodiment will be described with reference to FIG. 7 . During heating operation, the four-way valve 303's inlet / outlet ports a and b, as well as the inlet / outlet ports c and d, are opened. With the four-way valve 303 controlled in this manner, the circulation pump 302 is operated. As a result, as shown by the arrows in FIG. 7 , hot water is guided from the bottom of the hot water storage tank 301 through the four-way valve 303, the circulation pump 302, the heat pump unit 400, the four-way valve 303, and the top of the hot water storage tank 301 in this order. In this way, hot water taken out from the bottom of the hot water storage tank 301 is heated by the heat pump unit 400, which serves as a heating means, and the heated water can be sent to the top of the hot water storage tank 301. Through this heating operation, high-temperature hot water is gradually stacked from the top to the bottom of the hot water storage tank 301 (layered hot water storage). At this time, the hot water is maintained at a static pressure of 0.28 MPa via the pressure reducing valve 325 because the water supply end 321 is connected to a water supply and water pressure is applied to the hot water.

[0061] <Equalization Operation> Next, equalization operation of hot water storage type hot water heater 201 of Embodiment 4 will be described with reference to Figure 8. After the above-mentioned boiling operation, when hot water is used from bathtub 500 or hot water supply end 324, the hot water is mixed with tap water from water supply end 321 at mixing valve 322 or mixing valve 323 from above hot water storage tank 301 via pipe 314, and supplied to hot water supply end 324 or bathtub 500. In this case, tap water is supplied from water supply end 321 to the bottom of hot water storage tank 301 via pipe 315 and pipe 315a. Normally, tap water has a lower temperature than the hot water in hot water storage tank 301, and because of its greater density, it does not diffuse upward, and the temperature of the hot water in the bottom of hot water storage tank 301 drops. Generally, microorganisms, such as bacteria or mold, grow at water temperatures between 20°C and 40°C, and therefore, when the water temperature is maintained between 20°C and 40°C, microbial cells or a biofilm of accumulated microorganisms will adhere to the hot water below hot water storage tank 301 or to the wall surface of hot water storage tank 301. If microorganisms or biofilms adhere, the hygiene of the hot water cannot be maintained, so an equalization operation is performed to maintain hygiene below hot water storage tank 301. The equalization operation for equalizing the temperature inside hot water storage tank 301 is described below.

[0062] During equalization operation, inlet / outlet ports b and d, as well as inlet / outlet ports a and c of four-way valve 303, are opened. With four-way valve 303 controlled in this manner, circulation pump 302 is operated. As a result, as shown in FIG. 8 , hot water is guided from the top of hot water storage tank 301 through piping 314, four-way valve 303, piping 312, circulation pump 302, heat pump unit 400, piping 313, four-way valve 303, piping 311, and the bottom of hot water storage tank 301 in this order. At this time, heat pump unit 400 is not heated, and only water is passed through. In other words, by circulating high-temperature hot water taken from the top of hot water storage tank 301 to the bottom of hot water storage tank 301, the water temperature at the bottom of hot water storage tank 301 is raised to a temperature at which microorganisms do not easily grow, thereby enabling the temperature throughout hot water storage tank 301 to be equalized. At this time, microorganisms present inside the pipes 311, 312, 313, 314, the four-way valve 303, the circulation pump 302, and the heat pump unit 400 can be sterilized by using a combination of high temperature and static pressure.

[0063] In this way, in the hot water storage type hot water heater 201, the equalization operation pressurizes the hot water in the hot water storage tank 301 by static pressure and equalizes the temperature, thereby maintaining the hygiene of the interior of the hot water storage tank 301, the piping 311, 312, 313, 314, the four-way valve 303, the circulation pump 302, and the heat pump unit 400. If the temperature of the hot water in the upper part of the hot water storage tank 301 is low, the equalization operation has little sterilization effect, so the heat pump unit 400 may be operated simultaneously to heat the water. Alternatively, the equalization operation may be omitted and only the boiling operation may be performed to heat the hot water storage tank 301 to a predetermined temperature, for example, 50°C or higher. The equalization operation may be performed after the boiling operation when hot water is not being used, or immediately after the boiling operation. Because the temperature inside the hot water storage tank 301 may not be uniform even immediately after the boiling operation, performing this operation in this manner can suppress a drop in the temperature below the hot water storage tank 301.

[0064] In the hot water storage type hot water supply device of the fourth embodiment, the impact application unit of the first embodiment may be installed in the hot water storage tank and operated as described in the first embodiment. Also, the pressure sensor of the second embodiment may be installed in the hot water storage tank and operated as described in the second embodiment. Furthermore, the chemical addition unit and chemical concentration measurement unit of the third embodiment may be installed in the hot water storage tank and operated as described in the third embodiment.

[0065] As described above, in the water treatment device of the fourth embodiment, the water treatment device is a hot water storage type hot water supply device, the container is a hot water storage tank, the heating unit is a heat pump unit, and the pressurizing unit is a water treatment device including a water supply terminal connected to a water mains, a pipe connected from the water supply terminal to the hot water storage tank, and a pressure reducing valve installed in the pipe, and during the boiling operation in which hot water taken from the hot water storage tank is heated by the heat pump unit and then sent to the hot water storage tank, the static pressure in the hot water storage tank is fluctuated to a positive pressure by the water pressure of the water mains and the pressure reducing valve. This makes it possible to stably provide sterilized water even when a large number of microorganisms resistant to impact force are present in the water to be treated.

[0066] In addition, in a water treatment device according to a fourth embodiment, the water treatment device is a hot water storage type hot water supply device, the container is a hot water storage tank, the heating unit is a heat pump unit, and the pressurizing unit is a water treatment device comprising a water supply terminal connected to a water main, a pipe connected from the water supply terminal to the hot water storage tank, and a pressure reducing valve installed in the pipe, wherein during equalization operation to equalize the temperature of the hot water in the hot water storage tank, the static pressure in the hot water storage tank is fluctuated to a positive pressure by the water pressure of the water main and the pressure reducing valve. This makes it possible to consistently provide sterilized water even when a large number of microorganisms resistant to impact force are present in the water to be treated.

[0067] The control device 6 of the embodiment will now be described. The control device 6 is configured from a processor 1000 and a storage device 1010, as shown in FIG. 9 , which illustrates an example of hardware. The storage device 1010 includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory, both not shown. Alternatively, a hard disk auxiliary storage device may be provided instead of the flash memory. The processor 1000 executes a program input from the storage device 1010. In this case, the program is input to the processor 1000 from the auxiliary storage device via the volatile storage device. The processor 1000 may output data such as calculation results to the volatile storage device of the storage device 1010, or may store the data in the auxiliary storage device via the volatile storage device.

[0068] Although various exemplary embodiments and examples are described in this disclosure, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology of this disclosure. For example, this includes cases where at least one component is modified, added, or omitted, and even cases where at least one component is extracted and combined with components of another embodiment.

[0069] DESCRIPTION OF SYMBOLS 1 Container, 1a Opening, 2 Water to be treated, 3 Lid, 4 Impact application unit, 4a Oscillation surface, 5 Heating unit, 6 Control device, 7 Temperature sensor, 8 Pressurization unit, 9 Pressure sensor, 10 Chemical concentration measurement unit, 11 Chemical addition unit, 100 Water treatment device, 100A Water treatment device, 100B Water treatment device, 101 Water supply pipe, 102 Discharge pipe, 201 Hot water storage type hot water supply device, 300 Hot water storage unit, 301 Hot water storage tank, 302 Circulation pump, 303 Four-way valve, 311 Pipe, 312 Pipe, 313 Pipe, 314 Pipe, 315 Pipe, 315a Pipe, 316 Pipe, 317 Pipe, 321 Water supply end, 322 Mixing valve, 323 Mixing valve, 324 Hot water supply end, 325 Pressure reducing valve, 331 Thermistor, 332 Thermistor, 333 Thermistor, 334 Thermistor, 335 Thermistor, 400 Heat pump unit, 500 Bathtub.

Claims

1. A water treatment device that sterilizes water to be treated stored in a container, comprising at least one of an impact application unit that applies an impact to the water to be treated in the container to give it dynamic pressure, and a pressurization unit that changes the static pressure of the water to be treated in the container to the positive pressure side, and a heating unit that heats the water to be treated in the container according to a set heating temperature and retention time, wherein the heating unit heats at least one of the water to be treated after dynamic pressure has been applied by the impact application unit and the water to be treated in a state in which static pressure has been applied by the pressurization unit.

2. A water treatment device as described in claim 1, further comprising: a temperature sensor that measures the temperature of the water to be treated in the container; and a control device that adjusts the heating temperature and retention time by the heating unit based on the measurement value of the temperature sensor.

3. The water treatment device of claim 2, wherein the control device adjusts at least one of the heating temperature and the holding time to a value smaller than the standard heating temperature or standard holding time required to sterilize the treated water under atmospheric pressure without applying dynamic pressure by the impact application unit and static pressure by the pressurization unit.

4. A water treatment device as described in claim 2 or claim 3, further comprising a pressure sensor that measures at least one of the dynamic pressure applied by the impact application unit and the static pressure applied by the pressurization unit, and the control device adjusts at least one of the heating temperature applied by the heating unit and the retention time based on the measurement value of the pressure sensor.

5. A water treatment device as described in claim 4, further comprising a chemical measuring sensor for measuring the concentration of an oxidant or an antibacterial agent in the treated water, wherein the control device determines a pressure set value for at least one of the dynamic pressure and the static pressure based on the measurement value of the chemical measuring sensor, and adjusts the output of at least one of the impact application unit and the pressurization unit so that the measurement value of the pressure sensor becomes the pressure set value.

6. A water treatment device as described in claim 4, comprising: a chemical addition unit which adds an oxidizing agent or an antibacterial agent to the water to be treated; and a chemical measurement sensor which measures the concentration of the oxidizing agent or the antibacterial agent in the water to be treated, wherein the control device determines a pressure set value for at least one of the dynamic pressure or the static pressure based on the measurement value of the chemical measurement sensor, and adjusts the output of at least one of the impact application unit and the pressurization unit so that the measurement value of the pressure sensor becomes the pressure set value.

7. The water treatment device is a storage type hot water supply device, the container is a hot water storage tank, the heating unit is a heat pump unit, and the pressurizing unit is a water treatment device consisting of a water supply end connected to a water supply, a pipe connected from the water supply end to the hot water storage tank, and a pressure reducing valve installed on the pipe, wherein during boiling operation in which hot water taken out of the hot water storage tank is heated by the heat pump unit and then sent to the hot water storage tank, the static pressure in the hot water storage tank is changed to a positive pressure side by the water pressure of the water supply and the pressure reducing valve, according to any one of claims 1 to 6.

8. The water treatment device is a storage type hot water supply device, the container is a hot water storage tank, the heating unit is a heat pump unit, and the pressurizing unit is a water treatment device consisting of a water supply end connected to a water supply, a piping connected from the water supply end to the hot water storage tank, and a pressure reducing valve installed on the piping, wherein during equalization operation to equalize the temperature of the hot water in the hot water storage tank, the static pressure in the hot water storage tank is changed to a positive pressure side by the water pressure of the water supply and the pressure reducing valve, according to any one of claims 1 to 6.

9. A water treatment method for sterilizing water to be treated stored in a container, comprising: a pressurizing step of performing at least one of applying an impact to the water to be treated in the container to give it dynamic pressure, and changing the static pressure of the water to be treated in the container to the positive pressure side; and a heating step of heating the water to be treated in the container in accordance with a set heating temperature and retention time, wherein the heating step heats at least one of the water to be treated to which dynamic pressure has been applied by applying the impact, and the water to be treated to which static pressure changed to the positive pressure side has been applied.

10. The water treatment method according to claim 9, further comprising a temperature measuring step for measuring the temperature of the water to be treated in the container, and adjusting the heating temperature and retention time of the heating step based on the measured value of the temperature measuring step.

11. A water treatment method as described in claim 10, wherein in the heating process, at least one of the heating temperature and the holding time is adjusted to a value smaller than the standard heating temperature or standard holding time required to sterilize the treated water under atmospheric pressure without applying dynamic pressure due to the impact and static pressure fluctuated to the positive pressure side.

12. A water treatment method as described in any one of claims 9 to 11, further comprising a pressure measurement process for measuring at least one of the dynamic pressure due to the impact and the static pressure fluctuated to the positive pressure side, and in the heating process, at least one of the heating temperature and the holding time is adjusted based on the measurement value of the pressure measurement process.

13. A water treatment method as described in claim 12, further comprising a chemical measurement process for measuring a concentration of an oxidant or an antibacterial agent in the treated water, and wherein the pressurization process determines a pressure setting value of at least one of the dynamic pressure and the static pressure based on the measurement value of the chemical measurement process, and adjusts at least one of the dynamic pressure and the static pressure so that the measurement value of the pressure measurement process becomes the pressure setting value.

14. A water treatment method as described in claim 12, comprising: a chemical addition process for adding an oxidizing agent or an antibacterial agent to the water to be treated; and a chemical measurement process for measuring the concentration of the oxidizing agent or the antibacterial agent in the water to be treated, wherein the pressurizing process determines a pressure setting value for at least one of the dynamic pressure or the static pressure based on the measurement value in the chemical measurement process, and adjusts at least one of the dynamic pressure and the static pressure so that the measurement value in the pressure measurement process becomes the pressure setting value.

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