WO2023145082A1 - Filtration membrane cleaning apparatus, water treatment apparatus, and filtration membrane cleaning method - Google Patents

Filtration membrane cleaning apparatus, water treatment apparatus, and filtration membrane cleaning method Download PDF

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Publication number
WO2023145082A1
WO2023145082A1 PCT/JP2022/003625 JP2022003625W WO2023145082A1 WO 2023145082 A1 WO2023145082 A1 WO 2023145082A1 JP 2022003625 W JP2022003625 W JP 2022003625W WO 2023145082 A1 WO2023145082 A1 WO 2023145082A1
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WIPO (PCT)
Prior art keywords
water
ozonated
circulation
filtration membrane
ozone
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Application number
PCT/JP2022/003625
Other languages
French (fr)
Japanese (ja)
Inventor
祐樹 佐藤
佳史 林
英二 今村
清治 野田
Original Assignee
三菱電機株式会社
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Application filed by 三菱電機株式会社 filed Critical 三菱電機株式会社
Priority to JP2022525098A priority Critical patent/JP7120496B1/en
Priority to PCT/JP2022/003625 priority patent/WO2023145082A1/en
Publication of WO2023145082A1 publication Critical patent/WO2023145082A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D65/00—Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
    • B01D65/02—Membrane cleaning or sterilisation ; Membrane regeneration
    • B01D65/06—Membrane cleaning or sterilisation ; Membrane regeneration with special washing compositions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F21/00—Dissolving
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/231—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids by bubbling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/50—Mixing liquids with solids
    • B01F23/53—Mixing liquids with solids using driven stirrers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
    • B01F35/20—Measuring; Control or regulation
    • B01F35/21—Measuring
    • B01F35/213—Measuring of the properties of the mixtures, e.g. temperature, density or colour
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
    • B01F35/20—Measuring; Control or regulation
    • B01F35/22—Control or regulation
    • B01F35/222—Control or regulation of the operation of the driving system, e.g. torque, speed or power of motors; of the position of mixing devices or elements
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage

Definitions

  • the present disclosure relates to a filtration membrane cleaning device, a water treatment device, and a filtration membrane cleaning method.
  • Membrane filtration using a filtration membrane is known as a method for separating and removing contaminants from water to be treated such as sewage and industrial wastewater. Continuing the membrane filtration process causes contaminants to adhere to the surface and pores of the filtration membrane, causing clogging, thereby gradually lowering the filtration performance. Therefore, in order to maintain filtration performance, the filtration membrane is washed with ozone water.
  • ozone water For example, in the water treatment apparatus of Patent Document 1, non-ozonated water containing no ozone is fed to an ozonated water generating tower, and ozone gas is supplied to the non-ozonated water in the ozonated water generating tower to generate ozonated water. Wash the filtration membrane with ozone water.
  • the present disclosure has been made to solve the above-described problems, and aims to provide a filtration membrane cleaning device capable of suppressing a reduction in the cleaning effect of the filtration membrane.
  • the filtration membrane cleaning apparatus includes an ozone gas supply unit that supplies ozone gas, a non-ozonated water supply channel provided with a non-ozonated water supply pump that supplies non-ozonized water that is water that does not contain ozone, and non-ozonized water.
  • a flow path for generating ozone water by dissolving ozone gas supplied from the ozone gas supply unit into non-ozonated water supplied from the ozone water supply flow path, and a circulation pump for circulating the generated ozone water is provided,
  • a circulation channel to which the ozone gas supply unit and the non-ozonated water supply channel are connected, and an ozonated water supply pump that supplies part of the ozonized water circulating in the circulation channel to the filtration membrane are provided.
  • the water treatment apparatus includes a membrane separation tank having a filtration membrane for membrane filtration of water to be treated, a membrane filtration tank for storing the membrane filtered water subjected to membrane filtration by the membrane separation tank, and ozone gas.
  • a non-ozonated water supply channel provided with an ozone gas supply unit to supply, a non-ozonated water supply pump that supplies non-ozonated water that is water not containing ozone, and non-ozonated water supplied from the non-ozonated water supply channel
  • the ozonized water is generated by dissolving the ozone gas supplied from the ozone gas supply unit to the ozonated water supply unit.
  • the non-ozonated water supply pump simultaneously supplies the non-ozonated water to the passage, generates the ozonized water in the circulation passage, circulates the ozonated water in the circulation passage, and supplies the ozonated water to the filtration membrane.
  • a circulation pump, and a control unit that controls the ozone water supply pump.
  • the filtration membrane cleaning method includes the steps of supplying non-ozonated water, which is water containing no ozone, to the circulation flow path, and dissolving ozone gas in the non-ozonated water in the circulation flow path to generate ozonated water. circulating the ozonated water in the circulation channel; and supplying part of the ozonated water circulating in the circulation channel to the filtration membrane. The supply, the generation of ozonated water in the circulation channel, the circulation of the ozonized water in the circulation channel, and the supply of the ozonated water to the filtration membrane are performed simultaneously.
  • the non-ozonated water is supplied to the circulation flow path, and in the circulation flow path , circulating the ozonized water in the circulation channel, and supplying the ozonated water to the filtration membrane at the same time, thereby suppressing a reduction in the cleaning effect of the filtration membrane.
  • FIG. 1 is a schematic diagram of a water treatment apparatus according to Embodiment 1;
  • FIG. FIG. 2 is a schematic diagram showing an ozone water generating section and an ozone gas supply section according to Embodiment 1;
  • 4 is a flow chart showing filtration membrane treatment of Embodiment 1.
  • FIG. 4 is a flow chart showing a method for cleaning a filtration membrane according to Embodiment 1.
  • FIG. 1 is a schematic diagram of a water treatment device of a comparative example of Embodiment 1.
  • FIG. 2 is a schematic diagram of a water treatment apparatus according to Embodiment 2;
  • FIG. 4 is a flow chart showing a method for cleaning a filtration membrane according to Embodiment 2.
  • FIG. 3 is a schematic diagram of a water treatment device according to Embodiment 3.
  • FIG. 3 is a schematic diagram of a water treatment device according to Embodiment 3.
  • FIG. 1 is a schematic diagram of a water treatment device 100 of Embodiment 1.
  • the water treatment apparatus 100 includes a membrane separation tank 2 having a filtration membrane 3 for membrane filtration of the water 1 to be treated, and a membrane filtration tank 16 for storing the membrane filtered water 17 that has undergone membrane filtration in the membrane separation tank 2. , a membrane filtration channel 4 and a filtration membrane cleaning device.
  • pollutants are separated and removed by the filtration membrane 3 from the water 1 to be treated, which has been treated, for example, by the activated sludge method.
  • the water 1 to be treated is, for example, tap water, sewage, secondary treated water, industrial wastewater, seawater, human waste, etc., and flows into the membrane separation tank 2 through the water flow path 5 to be treated.
  • a sludge extraction channel 10 may be connected to the membrane separation tank 2 .
  • a sludge drawing pump 9 for drawing sludge is provided in the sludge drawing channel 10 .
  • an air diffuser 8 may be arranged at the bottom of the membrane separation tank 2 .
  • a membrane surface aeration blower 6 is connected to the air diffuser 8 via an air supply pipe 7 .
  • the material of the filtration membrane 3 is not limited, but a fluorine-based resin compound that has excellent resistance to ozone, which is a strong oxidizing agent, is preferable.
  • Other examples include polyolefins such as polyethylene, polypropylene, and polybutene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-ethylene copolymer.
  • Fluorinated resin compounds such as coalescence (ETFE), polychlorotrifluoroethylene (PCTFE), chlorotrifluoroethylene-ethylene copolymer (ECTFE), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), cellulose acetate , celluloses such as ethyl cellulose, ceramics, and the like may be used. Also, a combination of two or more of the above materials may be used.
  • filtration membrane 3 is not limited.
  • various filtration membranes 3 known in the art such as microfiltration (MF) membranes and ultrafiltration (UF) membranes, may be used.
  • the average pore diameter of the filtration membrane 3 is not limited, it is preferably 0.001 ⁇ m or more and 1 ⁇ m or less, more preferably 0.01 ⁇ m or more and 0.1 ⁇ m or less.
  • the filtration membrane 3 having an average pore size in this range not only contaminants adhering to the surface of the filtration membrane 3 in contact with the water to be treated 1, but also the surface of the filtration membrane 3 in contact with the membrane filtered water 17 or the filtration membrane 3 Contaminants chemically adhered in the pores of the can be efficiently removed.
  • the shape of the filtration membrane 3 is not limited.
  • it may have a shape known in the technical field, such as a cylindrical shape or a flat film shape.
  • an immersion type, a casing type, a monolith type, or the like may be employed.
  • the water flow method of the filtration membrane 3 is not limited. For example, a dead end filtration method or a cross-flow filtration method may be used.
  • An external pressure filtration method may be used in which the water to be treated 1 is allowed to flow outside the filtration membrane 3 and the membrane filtered water 17 is allowed to flow inside.
  • An internal pressure filtration system may be used.
  • the membrane filtration water tank 16 stores the membrane filtration water 17 that has undergone membrane filtration in the membrane separation tank 2 .
  • the membrane filtration channel 4 is, for example, a pipe, which connects the filtration membrane 3 and the membrane filtration water tank 16 and feeds the membrane filtration water 17 to the membrane filtration water tank 16 .
  • the membrane filtration flow path 4 includes a membrane filtration pump 12 , a membrane filtration water flow rate measuring means 13 and a pressure gauge 14 .
  • the membrane filtered water 17 separated in the membrane separation tank 2 by the membrane filtration pump 12 is sent to the membrane filtered water tank 16 through the membrane filtered water flow path 15 .
  • Membrane-filtered water flow rate measuring means 13 measures the flow rate of membrane-filtered water 17 flowing through the membrane filtration channel 4 .
  • the filtration membrane cleaning apparatus dissolves ozone gas in non-ozonated water, which is water containing no ozone, to generate ozone water 28, and uses the generated ozone water 28 to clean the filtration membrane 3.
  • the filter membrane cleaning device includes a non-ozonated water supply channel 21 , a circulation channel 29 , an ozone gas supply section 23 , an ozone water supply channel 35 and a control section 37 .
  • the non-ozonated water supply channel 21, the circulation channel 29, and the ozonated water supply channel 35 are formed by, for example, piping.
  • the non-ozonated water supply channel 21 is a channel that connects the membrane-filtered water tank 16 and the circulation channel 29 and supplies the membrane-filtered water 17 stored in the membrane-filtered water tank 16 to the circulation channel 29 . That is, in the present embodiment, the non-ozonated water used to generate the ozonated water 28 is the membrane-filtered water 17 stored in the membrane-filtered water tank 16 .
  • the non-ozonated water supply channel 21 has a switching unit 18 , a non-ozonated water supply pump 19 , and a non-ozonized water supply flow rate measuring means 20 .
  • the switching unit 18 opens and closes the non-ozonated water supply channel 21 according to instructions from the control unit 37 .
  • the non-ozonated water supply pump 19 supplies the membrane-filtered water 17 , which is non-ozonized water, from the membrane-filtered water tank 16 to the circulation flow path 29 .
  • the non-ozonated water supply flow rate measuring means 20 measures the flow rate of the non-ozonated water flowing through the non-ozonated water supply channel 21 .
  • the circulation channel 29 is a channel for generating the ozone water 28 and for circulating the generated ozone water 28 .
  • the circulation flow path 29 is connected with the ozone gas supply section 23 , the non-ozonated water supply flow path 21 , the ozone water supply flow path 35 , the ozone gas removal section 26 , and the overflow water flow path 27 .
  • the ozone gas removal unit 26 is, for example, a pipe for discharging the ozone gas that has not been dissolved in the ozone water 28 in the circulation flow path 29 from the circulation flow path 29 .
  • the overflow water channel 27 is a channel for removing the ozonized water 28 from the circulation channel 29 when the ozone water 28 circulates in the circulation channel 29 in an amount exceeding a preset amount.
  • the overflow water passage 27 is provided at a water level lower than the ozone gas removal portion 26 in the circulation passage 29 in order to prevent the ozone gas removal portion 26 from being mixed with the ozone water 28 .
  • the circulation flow path 29 also has a switching section 36 , a circulation pump 30 , a circulation flow rate measuring means 31 , and a dissolved ozone concentration measuring means 32 .
  • the switching unit 36 is, for example, a three-way valve that connects the circulation flow path 29 and the ozonized water supply flow path 35 and can switch the flow path of the ozonated water 28 according to an instruction from the control unit 37 .
  • the circulation pump 30 circulates the ozone water 28 in the circulation flow path 29 .
  • the circulation flow rate measuring means 31 measures the flow rate of the ozone water 28 flowing through the circulation flow path 29 .
  • the dissolved ozone concentration measuring means 32 measures the dissolved ozone concentration of the ozone water 28 in the circulation flow path 29, and is, for example, an absorbance type ozone concentration meter or an electrode type ozone concentration meter.
  • the dissolved ozone concentration measuring means 32 is preferably arranged between the switching portion 36 of the circulation flow path 29 and the portion to which the ozone gas supply portion 23 is connected.
  • the circulation flow path 29 may be provided with means for uniformly mixing the ozone water 28, such as a static mixer.
  • the ozone gas supply unit 23 generates ozone gas and supplies the generated ozone gas to the circulation flow path 29 .
  • the ozone raw material supplied to the ozone gas supply unit 23 is not limited.
  • oxygen generated by liquid oxygen, PSA (Pressure Swing Adsorption), or PVSA (Pressure Vacuum Swing Adsorption) may be used.
  • FIG. 2 is a schematic diagram showing the ozone water generator 22 and the ozone gas supply unit 23 of Embodiment 1.
  • FIG. FIG. 2 is an enlarged view showing details of the portion indicated by 22 in FIG.
  • the ozone water generator 22 is a portion of the circulation channel 29 to which the ozone gas supply part 23, the non-ozonated water supply channel 21, the ozone gas removal part 26, and the overflow water channel 27 are connected.
  • the ozone gas supply unit 23 is connected to the circulation flow path 29 and supplies ozone gas into the circulation flow path 29 . More specifically, the ozone water generator 22 of the circulation flow path 29 has an air diffuser 25 to which the ozone gas supply unit 23 is connected via an ozone gas supply pipe 24 .
  • the air diffuser 25 is used as a means for supplying ozone gas from the ozone gas supply unit 23 into the circulation flow path 29.
  • the means is capable of generating 28.
  • ejector type, mechanical stirring type, and downward injection type ozone gas supply means may be used.
  • the ozone water 28 generated by dissolving the ozone gas in the non-ozonized water supplied from the non-ozonized water supply channel 21 is circulated by the circulation pump 30 . More precisely, the non-ozonated water supplied from the non-ozonated water supply channel 21 to the circulation channel 29 is mixed with the ozonized water 28 circulating through the circulation channel 29 to become the diluted ozonated water 28. The ozone gas supplied from the ozone gas supply unit 23 is dissolved in the ozone water 28 thus obtained.
  • the water treatment apparatus 100 of the present embodiment supplies ozone gas from the ozone gas supply unit 23 into the circulation flow path 29 .
  • the water treatment apparatus 100 of the present embodiment can generate the ozonized water 28 in the ozonized water generating section 22 of the circulation flow path 29, so it is necessary to include the ozonized water generating tower provided in the conventional water treatment apparatus. There is no
  • the ozonated water generation tower provided in the conventional water treatment apparatus is a water tank designed to store the volume of ozonized water 28 necessary for cleaning the filtration membrane 3 .
  • the maximum capacity of the ozone water generator 22 of the present embodiment can be designed to be smaller than the capacity of the ozone water 28 required for cleaning the filtration membrane 3 .
  • the maximum capacity of the ozone water generator 22 is a quarter or less of the capacity of the ozone water 28 required for cleaning the filtration membrane 3 .
  • the ozone water generator 22 is a part of the circulation flow path 29, and the generated ozone water 28 is not stored in the ozone water generator 22 but circulated through the circulation flow path 29. It is different from the ozonated water generation tower provided in the water treatment equipment.
  • the ozonized water generating unit 22 is connected to the overflow water flow path 27, but the ozonized water generating tower provided in the conventional water treatment apparatus is generally not connected to the overflow water flow path 27.
  • the ozonated water supply channel 35 connects the circulation channel 29 and the filtration membrane 3 and supplies part of the ozonated water 28 circulating in the circulation channel 29 to the filtration membrane 3 .
  • a part of the ozone water supply channel 35 may be shared with the membrane filtration channel 4 .
  • FIG. 1 shows an example in which the ozone water supply channel 35 and the membrane filtration channel 4 are connected by the switching part 11 and the channel from the switching part 11 to the filtration membrane 3 is shared.
  • the switching unit 11 is, for example, a three-way valve capable of switching the flow path of the membrane-filtered water 17 or the ozone water 28 according to instructions from the control unit 37 .
  • the ozonated water supply flow path 35 includes an ozonized water supply pump 33 and an ozonized water supply flow rate measuring means 34 .
  • the ozone water supply pump 33 feeds the ozone water 28 from the circulation channel 29 to the filtration membrane 3 via the ozone water supply channel 35 .
  • the ozonated water supply flow rate measuring means 34 measures the flow rate of the ozonized water 28 flowing through the ozonized water supply channel 35 .
  • All pumps and switching units are connected to the control unit 37.
  • the control unit 37 controls the operations of all pumps and switching units. Also, the measurement results of all the flow rate measuring means and the pressure gauge 14 are sent to the control section 37 . Also, the control unit 37 controls the operation of the ozone gas supply unit 23 . A control method by the control unit 37 will be described later in the water treatment method.
  • Water treatment methods are roughly divided into membrane filtration and cleaning of the filtration membrane 3 .
  • the membrane filtration process the water to be treated 1 is treated by the activated sludge method, and then the filter membrane 3 is used to separate and remove contaminants. If the membrane filtration treatment is continuously performed, there is a problem that the filtration performance is lowered. Specifically, with continuous use of the filtration membrane 3, contaminants adhere to the surface of the filtration membrane 3 in contact with the water to be treated 1, the surface of the filtration membrane 3 in contact with the filtered water, and the pores of the filtration membrane 3. As a result, clogging occurs, and filtration performance gradually decreases.
  • the water treatment apparatus 100 periodically cleans the filtration membrane 3 .
  • the operation of the pump and the switching unit which will be described later, is controlled by the control unit 37 .
  • Switching between the membrane filtration process and the cleaning process of the filtration membrane 3 may be set by, for example, the time of the membrane filtration process.
  • FIG. 3 is a flow chart showing filtration membrane treatment according to the first embodiment.
  • the control unit 37 closes the circulation channel 29 side of the switching unit 11 and opens the membrane separation tank 2 side and the membrane filtration water tank 16 side (step S1). Then, the controller 37 activates the membrane filtration pump 12 (step S2). As a result, the water 1 to be treated is membrane-filtered by the filtration membrane 3 , and the membrane-filtered water 17 filtered by the filtration membrane 3 is sent to the membrane-filtered water tank 16 through the membrane-filtered channel 4 .
  • the control unit 37 constantly operates the membrane surface aeration blower 6 during the membrane filtration process, changes the operation time of the sludge extraction pump 9 according to the sludge concentration in the membrane separation tank 2, Pull out the sludge.
  • FIG. 4 is a flow chart showing a method for cleaning a filtration membrane according to Embodiment 1.
  • the control unit 37 stops the membrane filtration pump 12 to end the membrane filtration process (step S3). Then, the control unit 37 closes the membrane filtration tank 16 side of the switching unit 11 and opens the membrane separation tank 2 side and the circulation channel 29 side (step S4).
  • the control unit 37 performs preliminary cleaning of the filtration membrane 3 (step S5).
  • Pre-washing of the filtration membrane 3 is not essential, but pre-washing can facilitate removal of contaminants adhering to the surface of the filtration membrane 3 in contact with the water 1 to be treated.
  • the water treatment device 100 pre-washes the filtration membrane 3 using a pre-wash liquid that does not contain chemicals.
  • the control unit 37 opens the switching unit 36 and the switching unit 18 and activates the non-ozonated water supply pump 19 , the circulation pump 30 and the ozonated water supply pump 33 . Thereby, the control part 37 can water-feed the membrane filtered water 17 to the filtration membrane 3, and can implement preliminary washing.
  • the water treatment apparatus 100 may expose the filtration membrane 3 to air for a certain period of time to facilitate removal of contaminants adhering to the surface of the filtration membrane 3 in contact with the water 1 to be treated.
  • control unit 37 generates and circulates the ozone water 28 .
  • the control unit 37 closes the ozonized water supply channel 35 side of the switching unit 36 and opens the circulation channel 29 side so that the ozone water 28 circulates through the circulation channel 29 (step S6).
  • the ozone water 28 generated when the filtration membrane 3 was washed last time remains in the circulation flow path 29 .
  • the ozonized water 28 remaining in the circulation flow path 29 has a dissolved ozone concentration lower than that at the time of the previous cleaning treatment of the filtration membrane 3 because the time has passed since the previous cleaning treatment of the filtration membrane 3. It's becoming Therefore, the control unit 37 activates the circulation pump 30 and the ozone gas supply unit 23 (step S7).
  • the control unit 37 dissolves the ozone gas in the ozonized water 28 remaining in the circulation flow path 29 to generate the ozonized water 28 with a higher concentration, and circulates the generated ozonated water 28 in the circulation flow path 29. . Then, the controller 37 determines whether or not the value of the dissolved ozone concentration measuring means 32 has increased to a preset value (step S8). When the control unit 37 determines that the value of the dissolved ozone concentration measuring means 32 has not increased to the preset value, the ozone gas supply unit continues to operate until the value of the dissolved ozone concentration measuring means 32 increases to the preset value. Supply of ozone gas from 23 and circulation of ozone water 28 are performed.
  • the preset value in the dissolved ozone concentration measuring means 32 indicates that the dissolved ozone concentration of the ozonized water 28 decreases due to decomposition of ozone during the time until the ozonated water is supplied to the filtration membrane 3 through the ozonized water supply channel 35. Considering this, it is preferable to set the dissolved ozone concentration higher than the dissolved ozone concentration of the ozone water 28 to be achieved when supplied to the filtration membrane 3 . How much ozone is decomposed in the time before it is supplied to the filtration membrane 3 through the ozonized water supply channel 35 depends on the length of the ozonated water supply channel 35 and the supply flow rate. good.
  • the preset value in the dissolved ozone concentration measuring means 32 is preferably 10 mg/L or more and 50 mg/L or less. If the dissolved ozone concentration of the ozonated water 28 is lower than 10 mg/L, it takes time to decompose contaminants adhering to the filtration membrane 3, and the required amount of the ozonated water 28 increases. Such running costs increase. On the other hand, if the dissolved ozone concentration of the ozonized water 28 is higher than 50 mg/L, the operating time of the ozone gas supply unit 23 will be longer, so the running cost required to generate the ozonated water 28 will increase. In addition, the time during which the membrane filtration of the water 1 to be treated is interrupted is also lengthened, so the amount of membrane-filtered water 17 is reduced.
  • control unit 37 controls the switching unit 18 and the non-ozonated water supply pump 19 to supply a predetermined amount of non-ozonated water to the circulation passage 29. It is good to supply water.
  • the control unit 37 may generate and circulate the ozone water 28 at the same time as the membrane filtration process described above. That is, S1 to S2 and S4 to S8 in FIGS. 3 and 4 may be performed simultaneously. As a result, the cleaning process of the filtration membrane 3 can be started immediately after the membrane filtration process is finished.
  • step S9 A specific operation of the water treatment apparatus 100 will be described below.
  • the control unit 37 opens the switching unit 18, opens all directions of the switching unit 36, opens the circulation flow path 29 side and the membrane separation tank 2 side of the switching unit 11, and closes the membrane filtration water tank 16 side. Then, the controller 37 activates the non-ozonated water supply pump 19 and the ozonated water supply pump 33 . As a result, the non-ozonated water is supplied to the circulation channel 29, the ozonated water 28 is generated within the circulation channel 29, the ozonated water 28 is circulated within the circulation channel 29, and the ozonated water 28 is supplied to the filtration membrane 3. Feeding is carried out at the same time and backwashing of the filtration membrane 3 is started. As described above, the control unit 37 also continues to generate and circulate the ozonated water 28 , so the control unit 37 drives the circulation pump 30 in addition to the non-ozonated water supply pump 19 and the ozonated water supply pump 33 .
  • control unit 37 controls each pump as follows.
  • the flow rate of the non-ozonated water supplied from the non-ozonated water supply channel 21 to the circulation channel 29 and the flow rate of the ozonated water 28 supplied from the circulation channel 29 to the ozonated water supply channel 35 are made equal.
  • the control unit 37 increases the output of the non-ozonated water supply pump 19 so that the value of the non-ozonated water supply flow rate measuring means 20 also increases.
  • the output of the non-ozonated water supply pump 19 is controlled to be lowered so that the value of the non-ozonated water supply flow rate measuring means 20 also becomes low.
  • the control unit 37 controls the circulation pump 30 so that the flow rate of the ozonized water 28 in the circulation flow path 29 is higher than the flow rate of the ozonated water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35. . That is, the control unit 37 controls at least one of the circulation pump 30 and the ozone water supply pump 33 so that the value of the circulation flow rate measuring means 31 becomes higher than the value of the ozone water supply flow rate measuring means 34 . For example, when the value of the ozone water supply flow rate measuring means 34 is higher than the value of the circulation flow rate measuring means 31, the control section 37 controls the output of the circulation pump 30 to be increased.
  • the controller 37 dilutes the ozonized water 28 circulating in the circulation flow path 29 by supplying the non-ozonated water to the circulation flow path 29 , and reduces the dissolved ozone concentration measured by the dissolved ozone concentration measuring means 32 in the circulation flow path 29 .
  • the control unit 37 stops the non-ozonated water supply pump 19 and the ozonated water supply pump 33 , closes the ozonated water supply channel 35 side of the switching unit 36 , and closes the switching unit 18 . Then, the controller 37 continues to activate the circulation pump 30 .
  • the control unit 37 supplies the non-ozonated water to the circulation flow path 29 and the ozonated water 28 to the filtration membrane 3, and only the generation of the ozonized water 28 in the circulation flow path 29 and the circulation of the ozonated water 28 in the circulation flow path 29 are performed.
  • the dissolved ozone concentration of the ozone water 28 circulating in the circulation flow path 29 gradually increases.
  • the control unit 37 opens the ozonated water supply channel 35 side of the switching unit 36, opens the switching unit 18, and The supply pump 19 and the ozone water supply pump 33 are started. That is, the control unit 37 supplies non-ozonated water to the circulation flow path 29, generates the ozonated water 28 in the circulation flow path 29, circulates the ozonated water 28 in the circulation flow path 29, and filters the ozonated water 28.
  • the feed to the membrane 3 is carried out at the same time and the backwashing of the filtration membrane 3 is resumed. As a result, the dissolved ozone concentration of the ozone water 28 can be maintained at a preset threshold value or higher.
  • the time for the cleaning treatment of the filtration membrane 3 using the ozone water 28 is not particularly limited, and may be appropriately set according to the amount of contaminants adhering to the filtration membrane 3 and the like. In general, it is preferable that the filtration membrane 3 is washed for 60 minutes or less. The shorter the cleaning time, the better. If the cleaning time is long, the operating time of the ozone gas supply unit 23 and the operating time of the pump become longer, resulting in an increase in running cost. In addition, since the time during which the membrane treatment of the water 1 to be treated is interrupted also becomes longer, the amount of the membrane-filtered water 17 decreases.
  • the membrane surface permeation flux which is the amount of water supplied per filtration membrane area of the ozonized water 28, is not particularly limited as long as the flux that can be filled up to the end of the filtration membrane 3 can be secured.
  • the membrane surface permeation flux of the ozone water 28 is preferably 1 LMH (L/m2/h) or more and 60 LMH or less.
  • the membrane surface permeation flux of the ozonated water 28 is higher than 60 LMH, the supply speed of the ozonated water 28 is faster than the decomposition speed of the contaminants adhering to the filtration membrane 3, so the ozonized water that did not react with the contaminants 28 flows out of the filter membrane 3 .
  • the cleaning treatment of the filtration membrane 3 is a cleaning method in which the ozone water 28 is passed through the filtration membrane 3 and then the ozone water 28 is retained in the filtration membrane 3 as it is, or the filtration membrane 3 is washed with the ozone water 28 . It is possible to use a cleaning method such as immersing in and holding.
  • the ozone water 28 discharged from the filtration membrane 3 after the filtration membrane 3 has been washed can be discharged into the membrane separation tank 2 and used as the water to be treated 1 for membrane filtration.
  • the ozone water 28 discharged from the filtration membrane 3 after back washing may be separately collected and treated as a treated liquid.
  • the control unit 37 stops the non-ozonated water supply pump 19, the circulation pump 30, and the ozonated water supply pump 33 (step S10). Then, the control unit 37 closes the circulation flow path 29 side of the switching unit 11 and closes the switching unit 18 (step S11). As a result, the supply and circulation of the ozone water 28 are stopped. Then, the control unit 37 performs S1 and S2 shown in FIG. 3 and restarts the membrane filtration treatment of the water 1 to be treated. Thereby, the membrane filtration process of the to-be-processed water 1 can be performed continuously and efficiently.
  • FIG. 5 is a schematic diagram of a water treatment apparatus as a comparative example of Embodiment 1.
  • FIG. A conventional water treatment apparatus requires installation of an ozonated water generating tower for generating and storing the ozonized water 28 for cleaning the filtration membrane 3 . Therefore, in the conventional water treatment apparatus, securing a space for installing the ozonated water generating tower and the initial cost were problems.
  • the water treatment apparatus of the comparative example shown in FIG. 23 are connected, ozone water 28 is generated in the channel, and the generated ozone water 28 is supplied to the filtration membrane 3 . Since the water treatment apparatus of the comparative example generates the ozonized water 28 in the flow path, it is not necessary to install an ozonated water generating tower of the conventional water treatment apparatus.
  • the water treatment apparatus of the comparative example for example, when the distance from the ozone gas supply part 23 to the filtration membrane 3 is short, or when the supply flow rate of the ozone water 28 to the filtration membrane 3 is high, the flow path from the ozone gas supply part 23 Before the ozone gas supplied inside is sufficiently dissolved in the membrane filtered water 17, it is sent to the filtration membrane 3, and the dissolved ozone concentration in the ozone water 28 is supplied to the filtration membrane 3 without increasing to a preset value. There is a risk of being Therefore, the water treatment apparatus of the comparative example has a problem that the cleaning effect of the filtration membrane 3 is reduced.
  • a circulation flow path 29, which is a flow path for generating ozonated water 28 and is provided with a circulation pump 30 for circulating the generated ozonated water 28;
  • the non-ozonated water supply pump 19, the circulation pump 30, and the A control unit 37 for controlling the ozone water supply pump 33 is provided.
  • the water treatment apparatus 100 according to the present embodiment does not need to be provided with an ozonated water generation tower provided in conventional water treatment apparatuses.
  • the water treatment apparatus 100 of the present embodiment when the distance from the ozone gas supply unit 23 to the filtration membrane 3 is equal and the supply flow rate of the ozone water 28 to the filtration membrane 3 is equal Moreover, the water treatment apparatus 100 of the present embodiment can more easily maintain the dissolved ozone concentration of the ozone water 28 than the water treatment apparatus of the comparative example. Therefore, the water treatment apparatus 100 in the present embodiment can suppress reduction in the cleaning effect of the filtration membrane 3 more than the water treatment apparatus of the comparative example.
  • the water treatment apparatus 100 of the present embodiment dissolves ozone gas in the non-ozonized water in the circulation flow path 29 to generate the ozonated water 28 .
  • the water treatment apparatus 100 of the present embodiment supplies non-ozonated water to the circulation flow path 29, generates ozonated water 28 in the circulation flow path 29, circulates the ozonated water 28 in the circulation flow path 29, and the ozonized water 28 to the filtration membrane 3 at the same time, it is not necessary to store the ozonated water 28 in a volume necessary for cleaning the filtration membrane 3 . This eliminates the need to install an ozonated water generating tower, which is required in conventional water treatment equipment.
  • the same amount of ozone gas is used as ozone gas. If the ozone gas is supplied from the supply unit 23 to the flow path, the ozone gas may not be sufficiently dissolved depending on the distance from the ozone gas supply unit 23 to the filtration membrane 3 and the flow rate of the ozone water 28 supplied to the filtration membrane 3. There is a risk that the dissolved ozone concentration in 28 will be supplied to the filtration membrane 3 without increasing to a preset value.
  • the water treatment apparatus 100 of the present embodiment supplies non-ozonated water to the circulation passage 29, generates ozonated water 28 in the circulation passage 29, circulates the ozonated water 28 in the circulation passage 29, and ozonates the water.
  • the water 28 is supplied to the filtration membrane 3 at the same time. That is, not all of the ozone water 28 generated in the circulation flow path 29 is supplied to the filtration membrane 3, but a part of the ozone water 28 generated in the circulation flow path 29 is supplied to the filtration membrane 3, The part circulates through the circulation channel 29 . In this way, part of the generated ozonated water 28 circulates through the circulation flow path 29 , which lengthens the time until the ozonated water 28 is supplied to the filtration membrane 3 . It becomes easier to increase the concentration to a preset value. Therefore, the water treatment apparatus 100 in the present embodiment can suppress reduction in the cleaning effect of the filtration membrane 3 more than the water treatment apparatus of the comparative example.
  • the circulation channel 29 when the flow rate of the non-ozonated water supplied from the non-ozonated water supply channel 21 to the circulation channel 29 is greater than the flow rate of the ozonized water 28 supplied from the circulation channel 29 to the ozonized water supply channel 35, the circulation channel The dissolved ozone concentration of the ozone water 28 circulating through 29 is less likely to increase. In addition, since the ozonized water 28 discharged from the circulation flow path 29 is increased by the overflow water flow path 27, the ozonated water 28 is wasted.
  • the controller 37 controls the flow rate of the non-ozonated water supplied from the non-ozonated water supply channel 21 to the circulation channel 29 and the flow rate of the ozonized water 28 supplied from the circulation channel 29 to the ozonated water supply channel 35. At least one of the non-ozonated water supply pump 19 and the ozonated water supply pump 33 is controlled to be the same.
  • control unit 37 controls the circulation pump 30 and the ozone water so that the flow rate of the ozonized water 28 in the circulation flow path 29 is higher than the flow rate of the ozonized water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35 .
  • At least one of the supply pumps 33 is controlled.
  • x be the flow rate of the ozonated water 28 in the circulation flow path 29 of the present embodiment
  • y be the flow rate of the ozonated water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35 .
  • x > y.
  • control unit 37 controls both the flow rate of the ozonated water 28 in the circulation flow path 29 and the flow rate of the ozonated water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35 to x.
  • the flow rate of the ozonized water 28 supplied to the ozonized water supply channel 35 is high, the reduction of the dissolved ozone concentration of the ozonated water 28 can be suppressed, but the amount of the ozonized water 28 used increases.
  • the flow rate y of the ozonized water 28 supplied to the ozonized water supply channel 35 is lower than the flow rate x of the ozonized water 28 in the circulation channel 29. can reduce the amount used.
  • the control unit 37 controls both the flow rate of the ozonized water 28 in the circulation flow path 29 and the flow rate of the ozonated water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35 to y.
  • the flow rate x of the ozonated water 28 in the circulation flow path 29 is higher than the flow rate y of the ozonated water 28 supplied from the circulation flow path 29 to the ozonated water supply flow path 35. Therefore, a decrease in dissolved ozone concentration in the ozone water 28 can be suppressed.
  • the control unit 37 supplies the non-ozonated water to the circulation flow path 29 and the ozonated water 28.
  • the supply to the filtration membrane 3 is stopped, and only the generation of the ozonated water 28 within the circulation flow path 29 and the circulation of the ozonated water 28 within the circulation flow path 29 are performed.
  • the control unit 37 supplies the non-ozonated water to the circulation flow path 29 and the ozonated water.
  • the supply to the filtration membrane 3 of 28 is resumed.
  • the dissolved ozone concentration of the ozone water 28 can be maintained at a preset threshold value or higher.
  • the water treatment apparatus 100 of the present embodiment includes an ozone gas removal unit 26 connected to the circulation flow path 29 and discharging the ozone gas that has not been dissolved in the circulation flow path 29 from the circulation flow path 29 .
  • the ozone gas that is not dissolved in the ozone water 28 can be discharged from the circulation flow path 29, thereby preventing gas lock.
  • the water treatment apparatus 100 supplies the non-ozonated water to the circulation flow path 29 while supplying the ozonated water 28 to the filtration membrane 3, there is a possibility that the timings of starting the supply of the ozonized water 28 and the non-ozonated water do not always coincide. be. For example, consider a case where the supply of non-ozonated water to the circulation flow path 29 is started earlier than the supply of the ozonated water 28 to the filtration membrane 3 is started. In this case, the amount of water in the circulation flow path 29 temporarily exceeds the maximum capacity of the circulation flow path 29, causing loads on the flow path, the pump, and the switching section.
  • the water treatment apparatus 100 is connected to the circulation flow path 29, and when the ozonized water 28 exceeding the preset water amount circulates in the circulation flow path 29, the ozonized water 28 is removed from the circulation flow path 29.
  • a running water flow path 27 is provided.
  • the ozone water 28 circulating in the circulation channel 29 can be discharged from the circulation channel 29 when the amount of water in the circulation channel 29 temporarily exceeds the maximum capacity of the circulation channel 29 .
  • the overflow water channel 27 is provided at a water level lower than that of the ozone gas removing section 26 in the circulation channel 29 . As a result, it is possible to prevent the ozonated water 28 from entering the ozone gas removing portion 26 when the ozonized water 28 in the circulation flow path 29 increases.
  • the water treatment apparatus 100 of the present embodiment uses the membrane filtered water 17 as the non-ozonated water. This eliminates the need to newly provide a water tank for storing non-ozonated water.
  • FIG. 6 is a schematic diagram of the water treatment device 100 of Embodiment 2.
  • Embodiment 1 shows an example in which the washing water for washing the filtration membrane 3 is the ozone water 28 .
  • an example will be described in which at least two types of chemicals, ie, ozone water 28 and cleaning water containing chemicals other than ozone, are used as cleaning water for cleaning the filtration membrane 3 .
  • the basic configuration of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of the present embodiment is the same as that of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of Embodiment 1, only differences will be described. Further, the same reference numerals are assigned to the same configurations as those of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of Embodiment 1. As shown in FIG.
  • the ozone water 28 is referred to as the first cleaning water 28, and the cleaning water containing chemicals other than ozone is referred to as the second cleaning water 38.
  • the type of chemical contained in the second washing water 38 is not limited to one type.
  • a water treatment apparatus 100 equipped with the filter membrane cleaning apparatus of the present embodiment includes a cleaning channel 43 and a cleaning water tank 39 for storing second cleaning water 38 .
  • the cleaning channel 43 is a channel that connects the filtration membrane 3 and the cleaning water tank 39 .
  • FIG. 6 shows an example in which the flow path from the filtration membrane 3 to the switching portion 42 of the cleaning flow path 43 is shared with the membrane filtration flow path 4 and the ozone water supply flow path 35 .
  • the cleaning channel 43 includes a cleaning pump 40 for supplying the second cleaning water 38 stored in the cleaning water tank 39 to the filtration membrane 3 and a cleaning pump for measuring the flow rate of the second cleaning water 38 flowing through the cleaning channel 43 . It has flow rate measuring means 41 .
  • the type of chemical used in the second washing water 38 stored in the washing water tank 39 is not particularly limited as long as it is a substance capable of decomposing organic or inorganic substances other than ozone, and substances known in the art can be used.
  • agents capable of decomposing organic matter include sodium hypochlorite, hydrogen peroxide, and sodium hydroxide.
  • sodium hypochlorite is preferable as the type of chemical for the second washing water 38 because the chemical is inexpensive and the concentration can be easily maintained.
  • the types of chemicals in the second washing water 38 may be used singly or in combination of two or more.
  • the first agent When combining two or more agents capable of decomposing organic matter, the first agent preferably has a standard oxidation-reduction potential (25°C) of less than 2.0 V measured using a hydrogen electrode, and the second agent is hydrogen.
  • a standard oxidation-reduction potential (25° C.) measured using an electrode is preferably 2.0 V or more.
  • washing water containing sodium hypochlorite as the first chemical and ozone as the second chemical.
  • substances that can decompose inorganic substances are, for example, inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, and organic acids such as oxalic acid and citric acid. These may also be used singly or in combination of two or more. Two or more substances capable of decomposing organic substances and substances capable of decomposing inorganic substances may be used in combination. In that case, there is no limitation as to which one is used as the first drug or the second drug. For example, when a substance capable of decomposing organic substances is used as the first chemical, a substance capable of decomposing inorganic substances is used as the second chemical. When a substance capable of decomposing inorganic substances is used as the first chemical, a substance capable of decomposing organic substances may be used as the second chemical.
  • the drug concentration in the second washing water 38 is not particularly limited.
  • sodium hypochlorite (effective chlorine concentration) is 1.0 g/L or more and 5.0 g/L or less
  • sodium hydroxide is 1.0 g/L or more and 4.0 g/L.
  • hydrochloric acid, sulfuric acid, and nitric acid are 1.0 g/L or more and 10.0 g/L or less
  • oxalic acid is 1.0 g/L or more and 2.0 g/L or less
  • citric acid is 1 g/L.
  • L or more and 10 g/L or less is preferable.
  • the chemical concentration is lower than the above range, it takes time to decompose contaminants adhering to the filtration membrane 3, and as the amount of washing water 28 used increases, the capacity of the chemical tank also increases. On the other hand, if the concentration of the drug is higher than the above range, the amount of the drug to be used will increase, resulting in an increase in the cost required for the drug.
  • the time period for washing the filtration membrane 3 with the second washing water 38 is not particularly limited, and may be appropriately set according to the amount of contaminants adhering to the filtration membrane 3 and the like. In general, when using sodium hypochlorite, it is preferably 90 minutes or less, and when using oxalic acid or citric acid, it is preferably 5 minutes or more and 7 minutes or less.
  • the cleaning time of the filtration membrane 3 using the second cleaning water 38 is preferably short, and if the cleaning time is long, the membrane treatment of the water 1 to be treated is interrupted for a long time, resulting in a decrease in the amount of membrane filtered water.
  • the membrane surface permeation flux which is the amount of water supplied per membrane area of the second wash water 38, is not particularly limited. In general, it suffices if a flux that can be filled up to the end of the filtration membrane 3 can be secured. Specifically, when sodium hypochlorite is used, it is preferably 6 LMH (L/m 2 /h) or less. If the membrane surface permeation flux is too high, the required amount of the second washing water 38 increases, resulting in an increase in the cost required for the chemicals and an increase in the capacity of the chemical tank. If the membrane surface permeation flux is too low, the second wash water 38 will not be filled up to the end of the filtration membrane 3, and contaminants adhering to the filtration membrane 3 will not be decomposed.
  • All pumps and switching units are connected to the control unit 37. Also, the measurement results of all the flow rate measuring means and the pressure gauge 14 are sent to the control section 37 .
  • the control unit 37 controls operations of all pumps and switching units. Also, the control unit 37 controls the operation of the ozone supply unit.
  • the method for washing the filtration membrane 3 of the present embodiment includes a washing method in which the second washing water 38 is passed through the filtration membrane 3 and then the second washing water 38 is held as it is in the filtration membrane 3, A cleaning method of immersing and holding the membrane 3 in the second cleaning water 38 or the like can be used.
  • FIG. 7 is a flow chart showing the cleaning method of the filtration membrane 3 of Embodiment 2, and shows only the cleaning method of the filtration membrane 3 using the second washing water 38 .
  • the control unit 37 stops the membrane filtration pump 12 when the membrane filtration process is being performed (step S20). Next, the control unit 37 closes the membrane filtered water channel 15 side of the switching unit 42 and opens the cleaning channel 43 side (step S21). Then, the control unit 37 activates the washing pump 40 (step S22), supplies the second washing water 38 to the filtration membrane 3 through the washing flow path 43, and starts washing the filtration membrane 3. FIG. When finishing the cleaning process of the filtration membrane 3 using the second cleaning water 38, the control unit 37 stops the cleaning pump 40 (step S23) and closes the cleaning channel 43 side of the switching unit 42 (step S24). ), the supply of the second wash water 38 is stopped.
  • control unit 37 may generate and circulate ozone water 28 as the first cleaning water 28 at the same time as cleaning the filtration membrane 3 using the second cleaning water 38 described above.
  • the washing treatment of the filtration membrane 3 with the ozone water 28, which is the first washing water 28, can be started immediately. can be done.
  • the control unit 37 performs the cleaning process of the filtration membrane 3 using the ozone water 28 described in the first embodiment.
  • the ozone gas supplied from the ozone gas supply unit 23 is dissolved in the non-ozonated water supplied from the non-ozonated water supply channel 21 to form the ozone water 28.
  • a circulation channel 29 provided with a circulation pump 30 for circulating the generated ozone water 28, a supply of non-ozonated water to the circulation channel 29, and ozone in the circulation channel 29.
  • a non-ozonated water supply pump 19, a circulation pump 30, and an ozonated water supply pump are provided so as to simultaneously generate the water 28, circulate the ozonized water 28 in the circulation flow path 29, and supply the ozonated water 28 to the filtration membrane 3. and a control unit 37 for controlling 33 .
  • the water treatment apparatus 100 according to the present embodiment does not need to be provided with an ozonated water generation tower provided in the conventional water treatment apparatus.
  • the water treatment apparatus 100 of the present embodiment and the water treatment apparatus of the comparative example shown in FIG. When equal, the water treatment apparatus 100 of the present embodiment can more easily maintain the dissolved ozone concentration of the ozone water 28 than the water treatment apparatus of the comparative example shown in FIG. Therefore, the water treatment apparatus 100 according to the present embodiment can suppress reduction in the cleaning effect of the filtration membrane 3 more than the water treatment apparatus of the comparative example shown in FIG.
  • the water treatment apparatus 100 in the present embodiment includes a cleaning water tank 39 storing second cleaning water 38 containing chemicals other than ozone, and filtering the second cleaning water 38 stored in the cleaning water tank 39.
  • a wash pump 40 is provided for feeding the membrane 3 and further comprises a wash channel 43 connecting the filtration membrane 3 and the wash water bath 39 .
  • the filtration membrane 3 can be washed using both the first washing water 28 and the second washing water 38 which are the ozone water 28 .
  • control unit 37 may wash the filtration membrane 3 while diluting the second washing water 38 with the membrane filtered water 17 .
  • the control unit 37 closes the membrane filtered water channel 15 side of the switching unit 11 and opens the filtration membrane 3 side and the circulation channel 29 side.
  • the control unit 37 opens the cleaning channel 43 side of the switching unit 42 and opens the switching unit 18 and the switching unit 36 .
  • the controller 37 then activates the non-ozonated water supply pump 19 , the circulation pump 30 and the cleaning pump 40 . This makes it possible to wash the filtration membrane 3 while diluting the second washing water 38 with the membrane filtered water 17 .
  • control unit 37 adjusts at least one of the cleaning pump 40 and the non-ozonated water supply pump 19 according to the value of the cleaning flow rate measuring means 41 and the value of the non-ozonated water supply flow rate measuring means 20, so that the filtration membrane The concentration and flow rate of the diluted second wash water 38 supplied to 3 can be adjusted.
  • the filtration membrane 3 is washed using both the first washing water 28 and the second washing water 38 is shown, but the types of washing water are limited to two. do not have.
  • ozonized water 28 containing ozone cleaning water containing a substance capable of decomposing organic substances, and cleaning water containing inorganic substances may be used in combination.
  • the order of the washing waters for washing the filtration membrane 3 is not particularly limited.
  • the channel from the filtration membrane 3 to the switching part 42 of the cleaning channel 43 may be provided with means such as a static mixer for uniformly mixing the second cleaning water 38 and the membrane-filtered water 17 .
  • FIG. 8 is a schematic diagram of the water treatment device 100 of Embodiment 3.
  • Embodiment 1 and Embodiment 2 explained the example using the membrane filtered water 17 as non-ozonated water.
  • clarified water 45 other than membrane-filtered water 17 as non-ozonated water will be described.
  • the basic configuration of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of the present embodiment is the same as that of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of Embodiment 1 or Embodiment 2, there are differences only explained. Further, the same reference numerals are given to the same configurations as those of the water treatment apparatus 100 having the filtration membrane cleaning apparatus of Embodiments 1 and 2. As shown in FIG.
  • the water treatment apparatus 100 of the present embodiment includes a clarification water tank 44 in which clarified water 45 other than the membrane filtered water 17 is stored, and the non-ozonated water supply channel 21 connects the clarification water tank 44 and the circulation channel 29.
  • the clarified water 45 other than the membrane-filtered water 17 may be any water that can obtain the minimum water quality for producing the ozonized water 28. For example, tap water, industrial water, ion-exchanged water, pure water, and ultrapure At least one of water.
  • the cleaning treatment of the filtration membrane 3 of the present embodiment is the same as the cleaning treatment of the filtration membrane 3 described in the first or second embodiment, except that clarified water 45 is used as the non-ozonated water.
  • the ozone gas supplied from the ozone gas supply unit 23 is dissolved in the non-ozonated water supplied from the non-ozonated water supply channel 21 to form the ozone water 28.
  • a circulation channel 29 provided with a circulation pump 30 for circulating the generated ozone water 28, a supply of non-ozonated water to the circulation channel 29, and ozone in the circulation channel 29.
  • a non-ozonated water supply pump 19, a circulation pump 30, and an ozonated water supply pump are provided so as to simultaneously generate the water 28, circulate the ozonized water 28 in the circulation flow path 29, and supply the ozonated water 28 to the filtration membrane 3. and a control unit 37 for controlling 33 .
  • the water treatment apparatus 100 according to the present embodiment does not need to be provided with an ozonated water generation tower provided in the conventional water treatment apparatus.
  • the water treatment apparatus 100 of the present embodiment and the water treatment apparatus of the comparative example shown in FIG. When equal, the water treatment apparatus 100 of the present embodiment can more easily maintain the dissolved ozone concentration of the ozone water 28 than the water treatment apparatus of the comparative example shown in FIG. Therefore, the water treatment apparatus 100 according to the present embodiment can suppress reduction in the cleaning effect of the filtration membrane 3 more than the water treatment apparatus of the comparative example shown in FIG.
  • the water quality of the membrane filtered water 17 may be affected by the water quality of the water 1 to be treated. Therefore, if the membrane-filtered water 17 is used as the non-ozonated water, the ozone gas blown into the membrane-filtered water 17 reacts with the substances dissolved in the membrane-filtered water 17, and the amount of ozone that can be dissolved in the membrane-filtered water 17 decreases. There is As a result, a large amount of ozone gas is required to raise the dissolved ozone concentration of the ozone water 28, and it may take time to raise the dissolved ozone concentration to a preset concentration.
  • the drug reacts with the substance dissolved in the membrane-filtered water 17, and the drug concentration dissolved in the membrane-filtered water 17 increases. may decrease, and the cleaning effect of the filtration membrane 3 may decrease.
  • the water treatment apparatus 100 of the present embodiment uses clarified water 45 other than the membrane-filtered water 17 as non-ozonated water. Specifically, it is at least one of tap water, industrial water, ion-exchanged water, pure water, and ultrapure water. This makes it possible to efficiently and stably generate the ozonized water 28 and dilute the second wash water 38 compared to the case of using the membrane-filtered water 17 as the non-ozonated water.

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Abstract

This filtration membrane cleaning apparatus comprises: a circulation flow passage (29) in which ozone water (28) is generated through dissolving of ozone gas fed from an ozone gas supply unit (23), in non-ozone water fed from a non-ozone water supply flow passage (21) and which is provided with a circulation pump (30) that circulates the generated ozone water (28); and a control unit (37) which performs control on a non-ozone water supply pump (19), the circulation pump (30), and an ozone water supply pump (33) in such a manner as to cause supplying of non-ozone water to the circulation flow passage (29), generation of the ozone water (28) in the circulation flow passage (29), circulation of the ozone water (28) in the circulation flow passage (29), and supplying of the ozone water (28) to a filtration membrane (3) to take place simultaneously. With this configuration, a water treatment apparatus (100) according to an embodiment of the present invention is able to minimize decline of the cleaning effectiveness of the filtration membrane (3) without providing an ozone water generation column.

Description

濾過膜洗浄装置、水処理装置及び濾過膜洗浄方法Filtration membrane cleaning device, water treatment device, and filtration membrane cleaning method
　本開示は、濾過膜洗浄装置、水処理装置及び濾過膜洗浄方法に関する。 The present disclosure relates to a filtration membrane cleaning device, a water treatment device, and a filtration membrane cleaning method.
　下水、工場廃水等の被処理水の汚濁物質を分離除去する方法として、濾過膜を用いた膜濾過処理が知られている。膜濾過処理を継続して行うと、濾過膜の表面及び孔中に汚濁物質が付着し目詰まりが生じるため、濾過性能が徐々に低下する。そこで、濾過性能を維持するため、オゾン水を用いた濾過膜の洗浄が行われている。
　例えば特許文献１の水処理装置では、オゾンを含有しない非オゾン水をオゾン水生成塔へと送水し、オゾン水生成塔において非オゾン水にオゾンガスを供給することによりオゾン水が生成し、生成したオゾン水により濾過膜を洗浄する。 Membrane filtration using a filtration membrane is known as a method for separating and removing contaminants from water to be treated such as sewage and industrial wastewater. Continuing the membrane filtration process causes contaminants to adhere to the surface and pores of the filtration membrane, causing clogging, thereby gradually lowering the filtration performance. Therefore, in order to maintain filtration performance, the filtration membrane is washed with ozone water.
For example, in the water treatment apparatus of Patent Document 1, non-ozonated water containing no ozone is fed to an ozonated water generating tower, and ozone gas is supplied to the non-ozonated water in the ozonated water generating tower to generate ozonated water. Wash the filtration membrane with ozone water.
特開２００３－２５１１６０号公報Japanese Patent Application Laid-Open No. 2003-251160
　しかしながら、特許文献１の水処理装置では、濾過膜を洗浄するオゾン水を生成し貯蔵するためのオゾン水生成塔を設ける必要である。そのため、特許文献１の水処理装置では、オゾン水生成塔を設置するためのスペースの確保及びイニシャルコストが課題であった。そこで、オゾン水生成塔を設置することなくオゾン水を生成する方法として、オゾンガスを配管内に供給し、配管内の非オゾン水にオゾンガスを溶解させることにより、配管内でオゾン水を生成する方法を検討する。この方法を採用した場合、オゾンガス供給部から濾過膜までの距離が短い場合、又はオゾン水の濾過膜への供給速度が速い場合にオゾン水中の溶存オゾン濃度が予め設定された値まで上昇することなく濾過膜へ供給される虞がある。そのため、濾過膜の洗浄効果が低減するという課題があった。 However, in the water treatment apparatus of Patent Document 1, it is necessary to provide an ozonated water generating tower for generating and storing ozonized water for cleaning the filtration membrane. Therefore, in the water treatment apparatus of Patent Document 1, securing a space for installing the ozonated water generating tower and initial cost were problems. Therefore, as a method of generating ozonated water without installing an ozonated water generating tower, ozonized water is generated in a pipe by supplying ozonized gas into the pipe and dissolving the ozonated gas in the non-ozonized water in the pipe. Consider. When this method is adopted, if the distance from the ozone gas supply part to the filtration membrane is short, or if the supply speed of ozonated water to the filtration membrane is high, the concentration of dissolved ozone in the ozonated water will rise to a preset value. There is a risk that it will be supplied to the filtration membrane without Therefore, there is a problem that the cleaning effect of the filtration membrane is reduced.
　本開示は、上述した課題を解決するためになされたものであり、濾過膜の洗浄効果の低減を抑制することができる濾過膜洗浄装置を提供することを目的とするものである。 The present disclosure has been made to solve the above-described problems, and aims to provide a filtration membrane cleaning device capable of suppressing a reduction in the cleaning effect of the filtration membrane.
　本開示に係る濾過膜洗浄装置は、オゾンガスを供給するオゾンガス供給部と、オゾンを含有しない水である非オゾン水を供給する非オゾン水供給ポンプが設けられた非オゾン水供給流路と、非オゾン水供給流路から供給された非オゾン水にオゾンガス供給部により供給されたオゾンガスが溶解されてオゾン水が生成される流路であり、生成されたオゾン水を循環させる循環ポンプが設けられ、オゾンガス供給部及び非オゾン水供給流路が接続された循環流路と、循環流路を循環しているオゾン水の一部を濾過膜へ供給するオゾン水供給ポンプが設けられ、循環流路に接続されたオゾン水供給流路と、循環流路への非オゾン水の供給、循環流路内でのオゾン水の生成、循環流路内におけるオゾン水の循環、及びオゾン水の濾過膜への供給を同時に行うように、非オゾン水供給ポンプ、循環ポンプ、及びオゾン水供給ポンプを制御する制御部と、を備えたものである。 The filtration membrane cleaning apparatus according to the present disclosure includes an ozone gas supply unit that supplies ozone gas, a non-ozonated water supply channel provided with a non-ozonated water supply pump that supplies non-ozonized water that is water that does not contain ozone, and non-ozonized water. A flow path for generating ozone water by dissolving ozone gas supplied from the ozone gas supply unit into non-ozonated water supplied from the ozone water supply flow path, and a circulation pump for circulating the generated ozone water is provided, A circulation channel to which the ozone gas supply unit and the non-ozonated water supply channel are connected, and an ozonated water supply pump that supplies part of the ozonized water circulating in the circulation channel to the filtration membrane are provided. Supply of non-ozonated water to the connected ozonated water supply channel and circulation channel, generation of ozonated water in the circulation channel, circulation of ozonated water in the circulation channel, and supply of ozonated water to the filtration membrane and a control unit for controlling the non-ozonated water supply pump, the circulation pump, and the ozonated water supply pump so as to supply simultaneously.
　また、本開示に係る水処理装置は、被処理水を膜濾過処理する濾過膜を有する膜分離槽と、膜分離槽により膜濾過処理された膜濾過水を貯水する膜濾過水槽と、オゾンガスを供給するオゾンガス供給部と、オゾンを含有しない水である非オゾン水を供給する非オゾン水供給ポンプが設けられた非オゾン水供給流路と、非オゾン水供給流路から供給された非オゾン水にオゾンガス供給部により供給されたオゾンガスが溶解されてオゾン水が生成される流路であり、生成されたオゾン水を循環させる循環ポンプが設けられ、オゾンガス供給部及び非オゾン水供給流路が接続された循環流路と、循環流路を循環しているオゾン水の一部を濾過膜へ供給するオゾン水供給ポンプが設けられ、循環流路に接続されたオゾン水供給流路と、循環流路への非オゾン水の供給、循環流路内でのオゾン水の生成、循環流路内におけるオゾン水の循環、及びオゾン水の濾過膜への供給を同時に行うように、非オゾン水供給ポンプ、循環ポンプ、及びオゾン水供給ポンプを制御する制御部と、を備えたものである。 Further, the water treatment apparatus according to the present disclosure includes a membrane separation tank having a filtration membrane for membrane filtration of water to be treated, a membrane filtration tank for storing the membrane filtered water subjected to membrane filtration by the membrane separation tank, and ozone gas. A non-ozonated water supply channel provided with an ozone gas supply unit to supply, a non-ozonated water supply pump that supplies non-ozonated water that is water not containing ozone, and non-ozonated water supplied from the non-ozonated water supply channel The ozonized water is generated by dissolving the ozone gas supplied from the ozone gas supply unit to the ozonated water supply unit. and an ozonized water supply pump that supplies part of the ozonized water circulating in the circulation flow path to the filtration membrane. The non-ozonated water supply pump simultaneously supplies the non-ozonated water to the passage, generates the ozonized water in the circulation passage, circulates the ozonated water in the circulation passage, and supplies the ozonated water to the filtration membrane. , a circulation pump, and a control unit that controls the ozone water supply pump.
　また、本開示に係る濾過膜洗浄方法は、オゾンを含有しない水である非オゾン水を循環流路に供給するステップと、循環流路において非オゾン水にオゾンガスを溶解させてオゾン水を生成するステップと、循環流路においてオゾン水を循環させるステップと、循環流路を循環しているオゾン水の一部を濾過膜へ供給するステップと、を有し、循環流路への非オゾン水の供給、循環流路内でのオゾン水の生成、循環流路内におけるオゾン水の循環、及びオゾン水の濾過膜への供給を同時に行うことを特徴とする。 In addition, the filtration membrane cleaning method according to the present disclosure includes the steps of supplying non-ozonated water, which is water containing no ozone, to the circulation flow path, and dissolving ozone gas in the non-ozonated water in the circulation flow path to generate ozonated water. circulating the ozonated water in the circulation channel; and supplying part of the ozonated water circulating in the circulation channel to the filtration membrane. The supply, the generation of ozonated water in the circulation channel, the circulation of the ozonized water in the circulation channel, and the supply of the ozonated water to the filtration membrane are performed simultaneously.
　本開示によれば、非オゾン水にオゾンガスを溶解させて生成されるオゾン水を用いて濾過膜を洗浄する濾過膜洗浄装置において、循環流路への非オゾン水の供給、循環流路内でのオゾン水の生成、循環流路内におけるオゾン水の循環、及びオゾン水の濾過膜への供給を同時に行うことにより、濾過膜の洗浄効果の低減を抑制することができる濾過膜洗浄装置を提供する。 According to the present disclosure, in a filtration membrane cleaning device that cleans a filtration membrane using ozonized water generated by dissolving ozone gas in non-ozonated water, the non-ozonated water is supplied to the circulation flow path, and in the circulation flow path , circulating the ozonized water in the circulation channel, and supplying the ozonated water to the filtration membrane at the same time, thereby suppressing a reduction in the cleaning effect of the filtration membrane. do.
実施の形態１の水処理装置の概略図である。1 is a schematic diagram of a water treatment apparatus according to Embodiment 1; FIG. 実施の形態１のオゾン水生成部及びオゾンガス供給部を示す概略図である。FIG. 2 is a schematic diagram showing an ozone water generating section and an ozone gas supply section according to Embodiment 1; 実施の形態１の濾過膜処理を示すフローチャートである。4 is a flow chart showing filtration membrane treatment of Embodiment 1. FIG. 実施の形態１の濾過膜の洗浄方法を示すフローチャートである。4 is a flow chart showing a method for cleaning a filtration membrane according to Embodiment 1. FIG. 実施の形態１の比較例の水処理装置の概略図である。1 is a schematic diagram of a water treatment device of a comparative example of Embodiment 1. FIG. 実施の形態２の水処理装置の概略図である。2 is a schematic diagram of a water treatment apparatus according to Embodiment 2; FIG. 実施の形態２の濾過膜の洗浄方法を示すフローチャートである。4 is a flow chart showing a method for cleaning a filtration membrane according to Embodiment 2. FIG. 実施の形態３の水処理装置の概略図である。3 is a schematic diagram of a water treatment device according to Embodiment 3. FIG.
実施の形態１．
　図１を用いて、実施の形態１における濾過膜洗浄装置を備える水処理装置１００について説明する。図１は実施の形態１の水処理装置１００の概略図である。水処理装置１００は、被処理水１を膜濾過処理するための濾過膜３を備える膜分離槽２と、膜分離槽２において膜濾過処理された膜濾過水１７を貯水する膜濾過水槽１６と、膜濾過流路４と、濾過膜洗浄装置とを備える。 Embodiment 1.
A water treatment apparatus 100 including a filtration membrane cleaning apparatus according to Embodiment 1 will be described with reference to FIG. FIG. 1 is a schematic diagram of a water treatment device 100 of Embodiment 1. FIG. The water treatment apparatus 100 includes a membrane separation tank 2 having a filtration membrane 3 for membrane filtration of the water 1 to be treated, and a membrane filtration tank 16 for storing the membrane filtered water 17 that has undergone membrane filtration in the membrane separation tank 2. , a membrane filtration channel 4 and a filtration membrane cleaning device.
　膜分離槽２では、例えば活性汚泥法により処理した被処理水１を濾過膜３により汚濁物質を分離除去する。被処理水１は、例えば上水道、下水道、下水二次処理水、工業排水、海水、屎尿等であり、被処理水流路５を介して膜分離槽２に流入される。膜分離槽２には、汚泥引抜流路１０が接続されてもよい。汚泥引抜流路１０には汚泥を引抜くための汚泥引抜ポンプ９が設けられている。また、膜分離槽２の底部に散気装置８を配置してもよい。散気装置８には、空気供給配管７を介して膜面曝気ブロワー６が接続される。 In the membrane separation tank 2, pollutants are separated and removed by the filtration membrane 3 from the water 1 to be treated, which has been treated, for example, by the activated sludge method. The water 1 to be treated is, for example, tap water, sewage, secondary treated water, industrial wastewater, seawater, human waste, etc., and flows into the membrane separation tank 2 through the water flow path 5 to be treated. A sludge extraction channel 10 may be connected to the membrane separation tank 2 . A sludge drawing pump 9 for drawing sludge is provided in the sludge drawing channel 10 . Also, an air diffuser 8 may be arranged at the bottom of the membrane separation tank 2 . A membrane surface aeration blower 6 is connected to the air diffuser 8 via an air supply pipe 7 .
　濾過膜３の材質は限定されないが、強い酸化剤であるオゾンに対する耐性に優れたフッ素系樹脂化合物が好ましい。他にも例えば、ポリエチレン、ポリプロピレン、ポリブテン等のポリオレフィン、テトラフルオロエチレン・パーフルオロアルキルビニルエーテル共重合体（ＰＦＡ）、テトラフルオロエチレン－ヘキサフルオロプロピレン共重合体（ＦＥＰ）、テトラフルオロエチレン－エチレン共重合体（ＥＴＦＥ）、ポリクロロトリフルオロエチレン（ＰＣＴＦＥ）、クロロトリフルオロエチレン－エチレン共重合体（ＥＣＴＦＥ）、ポリフッ化ビニリデン（ＰＶＤＦ）、ポリテトラフルオロエチレン（ＰＴＦＥ）等のフッ素系樹脂化合物、酢酸セルロース、エチルセルロース等のセルロース類、セラミック等を用いるとよい。また、上述の材質を２種以上組み合わせたものであってもよい。 The material of the filtration membrane 3 is not limited, but a fluorine-based resin compound that has excellent resistance to ozone, which is a strong oxidizing agent, is preferable. Other examples include polyolefins such as polyethylene, polypropylene, and polybutene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-ethylene copolymer. Fluorinated resin compounds such as coalescence (ETFE), polychlorotrifluoroethylene (PCTFE), chlorotrifluoroethylene-ethylene copolymer (ECTFE), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), cellulose acetate , celluloses such as ethyl cellulose, ceramics, and the like may be used. Also, a combination of two or more of the above materials may be used.
　濾過膜３の種類は限定されない。例えば、精密濾過（ＭＦ）膜、限外濾過（ＵＦ）膜等当該技術分野において公知の各種濾過膜３を用いるとよい。 The type of filtration membrane 3 is not limited. For example, various filtration membranes 3 known in the art, such as microfiltration (MF) membranes and ultrafiltration (UF) membranes, may be used.
　濾過膜３の平均孔径は限定されないが、好ましくは０．００１μｍ以上１μｍ以下、より好ましくは０．０１μｍ以上０．１μｍ以下である。この範囲の平均孔径を有する濾過膜３を用いることにより、被処理水１と接する濾過膜３の表面に付着した汚濁物質だけでなく、膜濾過水１７と接する濾過膜３の表面又は濾過膜３の孔中に化学的に付着した汚濁物質を効率的に除去することができる。 Although the average pore diameter of the filtration membrane 3 is not limited, it is preferably 0.001 μm or more and 1 μm or less, more preferably 0.01 μm or more and 0.1 μm or less. By using the filtration membrane 3 having an average pore size in this range, not only contaminants adhering to the surface of the filtration membrane 3 in contact with the water to be treated 1, but also the surface of the filtration membrane 3 in contact with the membrane filtered water 17 or the filtration membrane 3 Contaminants chemically adhered in the pores of the can be efficiently removed.
　濾過膜３の形状は、限定されない。例えば、円筒状、平膜状等の当該技術分野において公知の形状にするとよい。また、浸漬型、ケーシング型、モノリス型等を採用してもよい。 The shape of the filtration membrane 3 is not limited. For example, it may have a shape known in the technical field, such as a cylindrical shape or a flat film shape. Alternatively, an immersion type, a casing type, a monolith type, or the like may be employed.
　濾過膜３の通水方式は、限定されない。例えば、全量濾過方式、クロスフロー濾過方式にするとよい。濾過膜３の外側に被処理水１を流し、内側に膜濾過水１７を流す外圧濾過方式であってもよく、濾過膜３の内側に被処理水１を流し、外側に膜濾過水１７を流す内圧濾過方式であってもよい。 The water flow method of the filtration membrane 3 is not limited. For example, a dead end filtration method or a cross-flow filtration method may be used. An external pressure filtration method may be used in which the water to be treated 1 is allowed to flow outside the filtration membrane 3 and the membrane filtered water 17 is allowed to flow inside. An internal pressure filtration system may be used.
　膜濾過水槽１６は、膜分離槽２により膜濾過処理された膜濾過水１７を貯水する。 The membrane filtration water tank 16 stores the membrane filtration water 17 that has undergone membrane filtration in the membrane separation tank 2 .
　膜濾過流路４は例えば配管であり、濾過膜３と膜濾過水槽１６とを接続し、膜濾過水１７を膜濾過水槽１６に送水する流路である。膜濾過流路４は、膜濾過ポンプ１２、膜濾過水流量測定手段１３、圧力計１４を備える。膜濾過処理の際、膜濾過ポンプ１２により膜分離槽２において分離された膜濾過水１７は膜濾過水流路１５を介して膜濾過水槽１６に送水される。膜濾過水流量測定手段１３は膜濾過流路４を流れる膜濾過水１７の流量を測定する。 The membrane filtration channel 4 is, for example, a pipe, which connects the filtration membrane 3 and the membrane filtration water tank 16 and feeds the membrane filtration water 17 to the membrane filtration water tank 16 . The membrane filtration flow path 4 includes a membrane filtration pump 12 , a membrane filtration water flow rate measuring means 13 and a pressure gauge 14 . During the membrane filtration process, the membrane filtered water 17 separated in the membrane separation tank 2 by the membrane filtration pump 12 is sent to the membrane filtered water tank 16 through the membrane filtered water flow path 15 . Membrane-filtered water flow rate measuring means 13 measures the flow rate of membrane-filtered water 17 flowing through the membrane filtration channel 4 .
　次に、濾過膜洗浄装置について説明する。濾過膜洗浄装置はオゾンを含有しない水である非オゾン水にオゾンガスを溶解させてオゾン水２８を生成し、生成したオゾン水２８を用いて濾過膜３を洗浄する。濾過膜洗浄装置は、非オゾン水供給流路２１、循環流路２９、オゾンガス供給部２３、オゾン水供給流路３５、及び制御部３７を備える。非オゾン水供給流路２１、循環流路２９、及びオゾン水供給流路３５は例えば配管等により形成される。 Next, the filtration membrane cleaning device will be explained. The filtration membrane cleaning apparatus dissolves ozone gas in non-ozonated water, which is water containing no ozone, to generate ozone water 28, and uses the generated ozone water 28 to clean the filtration membrane 3. FIG. The filter membrane cleaning device includes a non-ozonated water supply channel 21 , a circulation channel 29 , an ozone gas supply section 23 , an ozone water supply channel 35 and a control section 37 . The non-ozonated water supply channel 21, the circulation channel 29, and the ozonated water supply channel 35 are formed by, for example, piping.
　非オゾン水供給流路２１は膜濾過水槽１６と循環流路２９とを接続し、膜濾過水槽１６に貯水された膜濾過水１７を循環流路２９に供給する流路である。すなわち、本実施の形態において、オゾン水２８の生成に用いる非オゾン水は、膜濾過水槽１６に貯水された膜濾過水１７である。非オゾン水供給流路２１は、切替部１８、非オゾン水供給ポンプ１９、非オゾン水供給流量測定手段２０を有する。切替部１８は、制御部３７からの指示に従い非オゾン水供給流路２１を開閉する。非オゾン水供給ポンプ１９は膜濾過水槽１６から非オゾン水である膜濾過水１７を循環流路２９に供給する。非オゾン水供給流量測定手段２０は、非オゾン水供給流路２１を流れる非オゾン水の流量を測定する。 The non-ozonated water supply channel 21 is a channel that connects the membrane-filtered water tank 16 and the circulation channel 29 and supplies the membrane-filtered water 17 stored in the membrane-filtered water tank 16 to the circulation channel 29 . That is, in the present embodiment, the non-ozonated water used to generate the ozonated water 28 is the membrane-filtered water 17 stored in the membrane-filtered water tank 16 . The non-ozonated water supply channel 21 has a switching unit 18 , a non-ozonated water supply pump 19 , and a non-ozonized water supply flow rate measuring means 20 . The switching unit 18 opens and closes the non-ozonated water supply channel 21 according to instructions from the control unit 37 . The non-ozonated water supply pump 19 supplies the membrane-filtered water 17 , which is non-ozonized water, from the membrane-filtered water tank 16 to the circulation flow path 29 . The non-ozonated water supply flow rate measuring means 20 measures the flow rate of the non-ozonated water flowing through the non-ozonated water supply channel 21 .
　循環流路２９は、オゾン水２８が生成され、生成されたオゾン水２８を循環させるための流路である。循環流路２９には、オゾンガス供給部２３、非オゾン水供給流路２１、オゾン水供給流路３５、オゾンガス排除部２６、及び越流水流路２７が接続される。オゾンガス排除部２６は、循環流路２９においてオゾン水２８に溶解されなかったオゾンガスを循環流路２９から排出するための例えば配管である。越流水流路２７は、循環流路２９内において予め設定された水量を超えるオゾン水２８が循環する場合に、オゾン水２８を循環流路２９から排除するための流路である。越流水流路２７は、オゾンガス排除部２６にオゾン水２８が混入することを防ぐために、循環流路２９においてオゾンガス排除部２６よりも低い水位に設けられる。 The circulation channel 29 is a channel for generating the ozone water 28 and for circulating the generated ozone water 28 . The circulation flow path 29 is connected with the ozone gas supply section 23 , the non-ozonated water supply flow path 21 , the ozone water supply flow path 35 , the ozone gas removal section 26 , and the overflow water flow path 27 . The ozone gas removal unit 26 is, for example, a pipe for discharging the ozone gas that has not been dissolved in the ozone water 28 in the circulation flow path 29 from the circulation flow path 29 . The overflow water channel 27 is a channel for removing the ozonized water 28 from the circulation channel 29 when the ozone water 28 circulates in the circulation channel 29 in an amount exceeding a preset amount. The overflow water passage 27 is provided at a water level lower than the ozone gas removal portion 26 in the circulation passage 29 in order to prevent the ozone gas removal portion 26 from being mixed with the ozone water 28 .
　また、循環流路２９は、切替部３６、循環ポンプ３０、循環流量測定手段３１、及び溶存オゾン濃度測定手段３２を有する。切替部３６は、循環流路２９とオゾン水供給流路３５を接続し、制御部３７からの指示に従いオゾン水２８の流路を切替可能な例えば三方弁である。循環ポンプ３０は、循環流路２９においてオゾン水２８を循環させる。循環流量測定手段３１は、循環流路２９を流れるオゾン水２８の流量を測定する。溶存オゾン濃度測定手段３２は、循環流路２９におけるオゾン水２８の溶存オゾン濃度を測定し、例えば吸光度式オゾン濃度計又は電極式オゾン濃度計である。溶存オゾン濃度測定手段３２は、循環流路２９の切替部３６とオゾンガス供給部２３が接続された部分との間に配置するとよい。図示していないが、循環流路２９には、オゾン水２８を均一に混合する手段である例えばスタティックミキサーが設けられていてもよい。 The circulation flow path 29 also has a switching section 36 , a circulation pump 30 , a circulation flow rate measuring means 31 , and a dissolved ozone concentration measuring means 32 . The switching unit 36 is, for example, a three-way valve that connects the circulation flow path 29 and the ozonized water supply flow path 35 and can switch the flow path of the ozonated water 28 according to an instruction from the control unit 37 . The circulation pump 30 circulates the ozone water 28 in the circulation flow path 29 . The circulation flow rate measuring means 31 measures the flow rate of the ozone water 28 flowing through the circulation flow path 29 . The dissolved ozone concentration measuring means 32 measures the dissolved ozone concentration of the ozone water 28 in the circulation flow path 29, and is, for example, an absorbance type ozone concentration meter or an electrode type ozone concentration meter. The dissolved ozone concentration measuring means 32 is preferably arranged between the switching portion 36 of the circulation flow path 29 and the portion to which the ozone gas supply portion 23 is connected. Although not shown, the circulation flow path 29 may be provided with means for uniformly mixing the ozone water 28, such as a static mixer.
　オゾンガス供給部２３はオゾンガスを生成し、生成したオゾンガスを循環流路２９に供給する。オゾンガス供給部２３に供給されるオゾン原料は、限定されない。例えば、液体酸素、ＰＳＡ（Ｐｒｅｓｓｕｒｅ　Ｓｗｉｎｇ　Ａｄｓｏｒｐｔｉｏｎ）、ＰＶＳＡ（Ｐｒｅｓｓｕｒｅ　Ｖａｃｕｕｍ　Ｓｗｉｎｇ　Ａｄｓｏｒｐｔｉｏｎ）で生成した酸素を用いるとよい。 The ozone gas supply unit 23 generates ozone gas and supplies the generated ozone gas to the circulation flow path 29 . The ozone raw material supplied to the ozone gas supply unit 23 is not limited. For example, oxygen generated by liquid oxygen, PSA (Pressure Swing Adsorption), or PVSA (Pressure Vacuum Swing Adsorption) may be used.
　図２は実施の形態１のオゾン水生成部２２及びオゾンガス供給部２３を示す概略図である。図２は、図１の２２で示す部分の詳細を示す拡大図である。オゾン水生成部２２は、循環流路２９におけるオゾンガス供給部２３、非オゾン水供給流路２１、オゾンガス排除部２６、及び越流水流路２７が接続された部分である。オゾンガス供給部２３は循環流路２９に接続され、循環流路２９内にオゾンガスを供給する。より詳細には、循環流路２９のオゾン水生成部２２は散気装置２５を備え、散気装置２５にはオゾンガス供給配管２４を介してオゾンガス供給部２３が接続される。図２では、オゾンガス供給部２３から循環流路２９内にオゾンガスを供給する手段として散気装置２５を用いた場合を例示したが、循環流路２９内において非オゾン水にオゾンガスを溶解しオゾン水２８を生成し得る手段であれば特に限定されず、例えば、エジェクタ式、機械攪拌式、及び下方注入式のオゾンガスの供給手段を用いてもよい。 FIG. 2 is a schematic diagram showing the ozone water generator 22 and the ozone gas supply unit 23 of Embodiment 1. FIG. FIG. 2 is an enlarged view showing details of the portion indicated by 22 in FIG. The ozone water generator 22 is a portion of the circulation channel 29 to which the ozone gas supply part 23, the non-ozonated water supply channel 21, the ozone gas removal part 26, and the overflow water channel 27 are connected. The ozone gas supply unit 23 is connected to the circulation flow path 29 and supplies ozone gas into the circulation flow path 29 . More specifically, the ozone water generator 22 of the circulation flow path 29 has an air diffuser 25 to which the ozone gas supply unit 23 is connected via an ozone gas supply pipe 24 . FIG. 2 illustrates the case where the air diffuser 25 is used as a means for supplying ozone gas from the ozone gas supply unit 23 into the circulation flow path 29. There is no particular limitation as long as the means is capable of generating 28. For example, ejector type, mechanical stirring type, and downward injection type ozone gas supply means may be used.
　循環流路２９では非オゾン水供給流路２１から供給された非オゾン水にオゾンガスが溶解されることにより、生成されたオゾン水２８を循環ポンプ３０により循環する。より厳密には、非オゾン水供給流路２１から循環流路２９に供給された非オゾン水は循環流路２９を循環するオゾン水２８と混合して希釈されたオゾン水２８となり、この希釈されたオゾン水２８にオゾンガス供給部２３により供給されたオゾンガスが溶解される。 In the circulation channel 29 , the ozone water 28 generated by dissolving the ozone gas in the non-ozonized water supplied from the non-ozonized water supply channel 21 is circulated by the circulation pump 30 . More precisely, the non-ozonated water supplied from the non-ozonated water supply channel 21 to the circulation channel 29 is mixed with the ozonized water 28 circulating through the circulation channel 29 to become the diluted ozonated water 28. The ozone gas supplied from the ozone gas supply unit 23 is dissolved in the ozone water 28 thus obtained.
　上述のとおり本実施の形態の水処理装置１００は、オゾンガス供給部２３からオゾンガスを循環流路２９内に供給する。これにより、本実施の形態の水処理装置１００は、循環流路２９のオゾン水生成部２２においてオゾン水２８を生成することができるので、従来の水処理装置が備えるオゾン水生成塔を備える必要がない。 As described above, the water treatment apparatus 100 of the present embodiment supplies ozone gas from the ozone gas supply unit 23 into the circulation flow path 29 . As a result, the water treatment apparatus 100 of the present embodiment can generate the ozonized water 28 in the ozonized water generating section 22 of the circulation flow path 29, so it is necessary to include the ozonized water generating tower provided in the conventional water treatment apparatus. There is no
　従来の水処理装置が備えるオゾン水生成塔とは、濾過膜３を洗浄するために必要なオゾン水２８の容量を貯水可能に設計された水槽である。本実施の形態のオゾン水生成部２２の最大容量は、濾過膜３の洗浄に必要なオゾン水２８の容量よりも小さく設計することができる。例えば、オゾン水生成部２２の最大容量は、濾過膜３の洗浄に必要なオゾン水２８の容量の４分の１以下である。 The ozonated water generation tower provided in the conventional water treatment apparatus is a water tank designed to store the volume of ozonized water 28 necessary for cleaning the filtration membrane 3 . The maximum capacity of the ozone water generator 22 of the present embodiment can be designed to be smaller than the capacity of the ozone water 28 required for cleaning the filtration membrane 3 . For example, the maximum capacity of the ozone water generator 22 is a quarter or less of the capacity of the ozone water 28 required for cleaning the filtration membrane 3 .
　また、オゾン水生成部２２は循環流路２９の一部であり、生成されたオゾン水２８はオゾン水生成部２２に貯水されるのではなく、循環流路２９を循環する点においても従来の水処理装置が備えるオゾン水生成塔と異なる。 In addition, the ozone water generator 22 is a part of the circulation flow path 29, and the generated ozone water 28 is not stored in the ozone water generator 22 but circulated through the circulation flow path 29. It is different from the ozonated water generation tower provided in the water treatment equipment.
　さらに、オゾン水生成部２２は越流水流路２７が接続されるが、従来の水処理装置が備えるオゾン水生成塔は一般的に越流水流路２７が接続されていない。 Furthermore, the ozonized water generating unit 22 is connected to the overflow water flow path 27, but the ozonized water generating tower provided in the conventional water treatment apparatus is generally not connected to the overflow water flow path 27.
　図１に戻り、オゾン水供給流路３５は、循環流路２９と濾過膜３とを接続し、循環流路２９を循環しているオゾン水２８の一部を濾過膜３へ供給する流路である。オゾン水供給流路３５の一部は、膜濾過流路４と共有であってもよい。図１では、切替部１１によりオゾン水供給流路３５及び膜濾過流路４が接続され、切替部１１から濾過膜３までの流路が共有である例を示している。切替部１１は制御部３７の指示に従い膜濾過水１７又はオゾン水２８の流路を切替可能な例えば三方弁である。オゾン水供給流路３５は、オゾン水供給ポンプ３３及びオゾン水供給流量測定手段３４を備える。オゾン水供給ポンプ３３は、オゾン水供給流路３５を介して循環流路２９から濾過膜３へオゾン水２８を送水する。オゾン水供給流量測定手段３４は、オゾン水供給流路３５を流れるオゾン水２８の流量を測定する。 Returning to FIG. 1 , the ozonated water supply channel 35 connects the circulation channel 29 and the filtration membrane 3 and supplies part of the ozonated water 28 circulating in the circulation channel 29 to the filtration membrane 3 . is. A part of the ozone water supply channel 35 may be shared with the membrane filtration channel 4 . FIG. 1 shows an example in which the ozone water supply channel 35 and the membrane filtration channel 4 are connected by the switching part 11 and the channel from the switching part 11 to the filtration membrane 3 is shared. The switching unit 11 is, for example, a three-way valve capable of switching the flow path of the membrane-filtered water 17 or the ozone water 28 according to instructions from the control unit 37 . The ozonated water supply flow path 35 includes an ozonized water supply pump 33 and an ozonized water supply flow rate measuring means 34 . The ozone water supply pump 33 feeds the ozone water 28 from the circulation channel 29 to the filtration membrane 3 via the ozone water supply channel 35 . The ozonated water supply flow rate measuring means 34 measures the flow rate of the ozonized water 28 flowing through the ozonized water supply channel 35 .
　全てのポンプ及び切替部は制御部３７に接続されている。そして、制御部３７は、全てのポンプ及び切替部の動作を制御する。また、全ての流量測定手段および圧力計１４の測定結果は制御部３７に送信される。また、制御部３７はオゾンガス供給部２３の動作を制御する。制御部３７による制御方法については、後述する水処理方法で説明する。 All pumps and switching units are connected to the control unit 37. The control unit 37 controls the operations of all pumps and switching units. Also, the measurement results of all the flow rate measuring means and the pressure gauge 14 are sent to the control section 37 . Also, the control unit 37 controls the operation of the ozone gas supply unit 23 . A control method by the control unit 37 will be described later in the water treatment method.
　次に、水処理装置１００を用いた水処理方法について説明する。水処理方法は、膜濾過処理と濾過膜３の洗浄処理に大別される。膜濾過処理は、活性汚泥法により被処理水１を処理した後、濾過膜３を用いて汚濁物質を分離除去する。膜濾過処理を継続して行うと、濾過性能が低下するという問題がある。具体的には、濾過膜３の継続的な使用に伴い、被処理水１に接する濾過膜３の表面、濾過水と接する濾過膜３の表面、濾過膜３の孔中にそれぞれ汚濁物質が付着して目詰まりが生じ、濾過性能が徐々に低下する。特に、濾過膜３に目詰りが生じると、膜濾過処理の際に必要な圧力が増加する。そのため、膜濾過流束、単位時間及び単位膜面積当たりの膜濾過水量が低下する。そこで、水処理装置１００は、濾過膜３の性能を維持するため、定期的に濾過膜３の洗浄処理を行う。後述のポンプ及び切替部の動作は制御部３７により制御される。 Next, a water treatment method using the water treatment device 100 will be described. Water treatment methods are roughly divided into membrane filtration and cleaning of the filtration membrane 3 . In the membrane filtration process, the water to be treated 1 is treated by the activated sludge method, and then the filter membrane 3 is used to separate and remove contaminants. If the membrane filtration treatment is continuously performed, there is a problem that the filtration performance is lowered. Specifically, with continuous use of the filtration membrane 3, contaminants adhere to the surface of the filtration membrane 3 in contact with the water to be treated 1, the surface of the filtration membrane 3 in contact with the filtered water, and the pores of the filtration membrane 3. As a result, clogging occurs, and filtration performance gradually decreases. In particular, when the filtration membrane 3 is clogged, the pressure required for membrane filtration increases. Therefore, the membrane filtration flux, the membrane filtration water amount per unit time and unit membrane area are lowered. Therefore, in order to maintain the performance of the filtration membrane 3 , the water treatment apparatus 100 periodically cleans the filtration membrane 3 . The operation of the pump and the switching unit, which will be described later, is controlled by the control unit 37 .
　膜濾過処理と濾過膜３の洗浄処理の切換えは、例えば膜濾過処理の時間によって設定すればよい。 Switching between the membrane filtration process and the cleaning process of the filtration membrane 3 may be set by, for example, the time of the membrane filtration process.
　まず、膜濾過処理について説明する。図３は実施の形態１の濾過膜処理を示すフローチャートである。
　制御部３７は、切替部１１の循環流路２９側を閉じ、膜分離槽２側及び膜濾過水槽１６側を開く（ステップＳ１）。そして、制御部３７は膜濾過ポンプ１２を起動させる（ステップＳ２）。これにより、被処理水１が濾過膜３で膜濾過され、濾過膜３で濾過された膜濾過水１７が膜濾過流路４を介して膜濾過水槽１６へ送水される。また、制御部３７は、膜濾過処理中は膜面曝気ブロワー６を常時稼働させ、汚泥引抜ポンプ９を膜分離槽２内の汚泥濃度に応じて稼働時間を変更させ、膜分離槽２内の汚泥の引抜を行う。 First, the membrane filtration process will be explained. FIG. 3 is a flow chart showing filtration membrane treatment according to the first embodiment.
The control unit 37 closes the circulation channel 29 side of the switching unit 11 and opens the membrane separation tank 2 side and the membrane filtration water tank 16 side (step S1). Then, the controller 37 activates the membrane filtration pump 12 (step S2). As a result, the water 1 to be treated is membrane-filtered by the filtration membrane 3 , and the membrane-filtered water 17 filtered by the filtration membrane 3 is sent to the membrane-filtered water tank 16 through the membrane-filtered channel 4 . In addition, the control unit 37 constantly operates the membrane surface aeration blower 6 during the membrane filtration process, changes the operation time of the sludge extraction pump 9 according to the sludge concentration in the membrane separation tank 2, Pull out the sludge.
　次に、濾過膜３の洗浄処理について説明する。図４は実施の形態１の濾過膜の洗浄方法を示すフローチャートである。　膜濾過処理を行っていた場合は、制御部３７は、膜濾過ポンプ１２を停止して膜濾過処理を終了させる（ステップＳ３）。そして、制御部３７は、切替部１１の膜濾過水槽１６側を閉じ、膜分離槽２側及び循環流路２９側を開く（ステップＳ４）。 Next, the cleaning process of the filtration membrane 3 will be described. FIG. 4 is a flow chart showing a method for cleaning a filtration membrane according to Embodiment 1. FIG. When the membrane filtration process is being performed, the control unit 37 stops the membrane filtration pump 12 to end the membrane filtration process (step S3). Then, the control unit 37 closes the membrane filtration tank 16 side of the switching unit 11 and opens the membrane separation tank 2 side and the circulation channel 29 side (step S4).
　次に、制御部３７は濾過膜３の予備洗浄を実施する（ステップＳ５）。濾過膜３の予備洗浄は必須ではないが、予備洗浄を行うことで被処理水１と接する濾過膜３の表面に付着した汚濁物質を除去し易くすることができる。具体的には、水処理装置１００は、薬剤を含有していない予備洗浄液を用いて濾過膜３を予備洗浄する。例えば、制御部３７は、切替部３６及び切替部１８を開き、非オゾン水供給ポンプ１９、循環ポンプ３０、及びオゾン水供給ポンプ３３を起動する。これにより、制御部３７は、膜濾過水１７を濾過膜３へ送水して、予備洗浄を実施することができる。また、水処理装置１００は濾過膜３を一定時間空気に曝すことにより、被処理水１と接する濾過膜３の表面に付着した汚濁物質を除去し易くしてもよい。 Next, the control unit 37 performs preliminary cleaning of the filtration membrane 3 (step S5). Pre-washing of the filtration membrane 3 is not essential, but pre-washing can facilitate removal of contaminants adhering to the surface of the filtration membrane 3 in contact with the water 1 to be treated. Specifically, the water treatment device 100 pre-washes the filtration membrane 3 using a pre-wash liquid that does not contain chemicals. For example, the control unit 37 opens the switching unit 36 and the switching unit 18 and activates the non-ozonated water supply pump 19 , the circulation pump 30 and the ozonated water supply pump 33 . Thereby, the control part 37 can water-feed the membrane filtered water 17 to the filtration membrane 3, and can implement preliminary washing. Further, the water treatment apparatus 100 may expose the filtration membrane 3 to air for a certain period of time to facilitate removal of contaminants adhering to the surface of the filtration membrane 3 in contact with the water 1 to be treated.
　次に、制御部３７はオゾン水２８の生成及び循環を行う。まず、制御部３７は、切替部３６のオゾン水供給流路３５側を閉じ、オゾン水２８が循環流路２９を循環するように循環流路２９側を開ける（ステップＳ６）。この際、循環流路２９内には前回濾過膜３の洗浄処理を実施した際に生成されたオゾン水２８が残っている。循環流路２９内に残っているオゾン水２８は、前回の濾過膜３の洗浄処理から時間が経過しているためオゾンが分解され溶存オゾン濃度は前回の濾過膜３の洗浄処理時よりも低くなっている。そこで、制御部３７は、循環ポンプ３０及びオゾンガス供給部２３を起動させる（ステップＳ７）。これにより、制御部３７は、循環流路２９内に残留するオゾン水２８にオゾンガスを溶解させ、より高濃度なオゾン水２８を生成し、生成したオゾン水２８を循環流路２９内で循環させる。そして、制御部３７は溶存オゾン濃度測定手段３２の値が予め設定された値に上昇したか否かを判断する（ステップＳ８）。制御部３７は溶存オゾン濃度測定手段３２の値が予め設定された値に上昇していないと判断した場合は、溶存オゾン濃度測定手段３２の値が予め設定された値に上昇するまでオゾンガス供給部２３からのオゾンガスの供給とオゾン水２８の循環を実施する。 Next, the control unit 37 generates and circulates the ozone water 28 . First, the control unit 37 closes the ozonized water supply channel 35 side of the switching unit 36 and opens the circulation channel 29 side so that the ozone water 28 circulates through the circulation channel 29 (step S6). At this time, the ozone water 28 generated when the filtration membrane 3 was washed last time remains in the circulation flow path 29 . The ozonized water 28 remaining in the circulation flow path 29 has a dissolved ozone concentration lower than that at the time of the previous cleaning treatment of the filtration membrane 3 because the time has passed since the previous cleaning treatment of the filtration membrane 3. It's becoming Therefore, the control unit 37 activates the circulation pump 30 and the ozone gas supply unit 23 (step S7). As a result, the control unit 37 dissolves the ozone gas in the ozonized water 28 remaining in the circulation flow path 29 to generate the ozonized water 28 with a higher concentration, and circulates the generated ozonated water 28 in the circulation flow path 29. . Then, the controller 37 determines whether or not the value of the dissolved ozone concentration measuring means 32 has increased to a preset value (step S8). When the control unit 37 determines that the value of the dissolved ozone concentration measuring means 32 has not increased to the preset value, the ozone gas supply unit continues to operate until the value of the dissolved ozone concentration measuring means 32 increases to the preset value. Supply of ozone gas from 23 and circulation of ozone water 28 are performed.
　溶存オゾン濃度測定手段３２における予め設定された値は、オゾン水供給流路３５を介して濾過膜３へ供給されるまでの時間にオゾンが分解されオゾン水２８の溶存オゾン濃度が減少することを考慮して、濾過膜３へ供給される際に達成したいオゾン水２８の溶存オゾン濃度よりも高く設定するとよい。オゾン水供給流路３５を介して濾過膜３へ供給されるまでの時間にオゾンがどの程度分解されるかは、オゾン水供給流路３５の長さ及び供給流量により異なるため、実験により検証するとよい。 The preset value in the dissolved ozone concentration measuring means 32 indicates that the dissolved ozone concentration of the ozonized water 28 decreases due to decomposition of ozone during the time until the ozonated water is supplied to the filtration membrane 3 through the ozonized water supply channel 35. Considering this, it is preferable to set the dissolved ozone concentration higher than the dissolved ozone concentration of the ozone water 28 to be achieved when supplied to the filtration membrane 3 . How much ozone is decomposed in the time before it is supplied to the filtration membrane 3 through the ozonized water supply channel 35 depends on the length of the ozonated water supply channel 35 and the supply flow rate. good.
　溶存オゾン濃度測定手段３２における予め設定された値は１０ｍｇ／Ｌ以上５０ｍｇ／Ｌ以下が好ましい。オゾン水２８の溶存オゾン濃度が１０ｍｇ／Ｌより低い場合、濾過膜３に付着した汚濁物質の分解に時間を要し、オゾン水２８の必要量が増大したりするため、濾過膜３の洗浄に係るランニングコストが増大する。一方、オゾン水２８の溶存オゾン濃度が５０ｍｇ／Ｌより高いと、オゾンガス供給部２３の稼働時間が長くなるため、オゾン水２８の生成に要するランニングコストが増大する。また、被処理水１の膜濾過を中断する時間も長くなるため、膜濾過水１７量が低下する。 The preset value in the dissolved ozone concentration measuring means 32 is preferably 10 mg/L or more and 50 mg/L or less. If the dissolved ozone concentration of the ozonated water 28 is lower than 10 mg/L, it takes time to decompose contaminants adhering to the filtration membrane 3, and the required amount of the ozonated water 28 increases. Such running costs increase. On the other hand, if the dissolved ozone concentration of the ozonized water 28 is higher than 50 mg/L, the operating time of the ozone gas supply unit 23 will be longer, so the running cost required to generate the ozonated water 28 will increase. In addition, the time during which the membrane filtration of the water 1 to be treated is interrupted is also lengthened, so the amount of membrane-filtered water 17 is reduced.
　仮に、循環流路２９内にオゾン水２８が残っていない場合は、制御部３７は切替部１８及び非オゾン水供給ポンプ１９を制御して、循環流路２９に予め設定された水量の非オゾン水を供給するとよい。 If the ozonized water 28 does not remain in the circulation passage 29, the control unit 37 controls the switching unit 18 and the non-ozonated water supply pump 19 to supply a predetermined amount of non-ozonated water to the circulation passage 29. It is good to supply water.
　制御部３７はオゾン水２８の生成及び循環を、上述の膜濾過処理と同時に実施してもよい。すなわち、図３及び図４においてＳ１～Ｓ２とＳ４～Ｓ８とを同時に実施してもよい。これにより、膜濾過処理が終了後に、速やかに濾過膜３の洗浄処理を開始することができる。 The control unit 37 may generate and circulate the ozone water 28 at the same time as the membrane filtration process described above. That is, S1 to S2 and S4 to S8 in FIGS. 3 and 4 may be performed simultaneously. As a result, the cleaning process of the filtration membrane 3 can be started immediately after the membrane filtration process is finished.
　次に、オゾン水２８の濾過膜３への供給を開始し、濾過膜３の逆洗浄を実施する場合について説明する。制御部３７は、循環流路２９への非オゾン水の供給、循環流路２９内でのオゾン水２８の生成、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給を同時に行うように、非オゾン水供給ポンプ１９、循環ポンプ３０、及びオゾン水供給ポンプ３３を制御する（ステップＳ９）。具体的な水処理装置１００の動作を以下に説明する。 Next, a case will be described in which the supply of the ozone water 28 to the filtration membrane 3 is started and the filtration membrane 3 is backwashed. The control unit 37 controls the supply of non-ozonated water to the circulation flow path 29, the generation of the ozonated water 28 within the circulation flow path 29, the circulation of the ozonated water 28 within the circulation flow path 29, and the filtering membrane 3 of the ozonated water 28. (step S9). A specific operation of the water treatment apparatus 100 will be described below.
　まず、制御部３７は、切替部１８を開け、切替部３６の全方向を開け、切替部１１の循環流路２９側及び膜分離槽２側を開けて膜濾過水槽１６側を閉じる。そして、制御部３７は、非オゾン水供給ポンプ１９及びオゾン水供給ポンプ３３を起動する。これにより、循環流路２９への非オゾン水の供給、循環流路２９内でのオゾン水２８の生成、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給が同時に行われ、濾過膜３の逆洗浄が開始される。上述のとおり、制御部３７はオゾン水２８の生成及び循環も継続して行うため、制御部３７は非オゾン水供給ポンプ１９及びオゾン水供給ポンプ３３に加え、循環ポンプ３０も駆動させている。 First, the control unit 37 opens the switching unit 18, opens all directions of the switching unit 36, opens the circulation flow path 29 side and the membrane separation tank 2 side of the switching unit 11, and closes the membrane filtration water tank 16 side. Then, the controller 37 activates the non-ozonated water supply pump 19 and the ozonated water supply pump 33 . As a result, the non-ozonated water is supplied to the circulation channel 29, the ozonated water 28 is generated within the circulation channel 29, the ozonated water 28 is circulated within the circulation channel 29, and the ozonated water 28 is supplied to the filtration membrane 3. Feeding is carried out at the same time and backwashing of the filtration membrane 3 is started. As described above, the control unit 37 also continues to generate and circulate the ozonated water 28 , so the control unit 37 drives the circulation pump 30 in addition to the non-ozonated water supply pump 19 and the ozonated water supply pump 33 .
　ここで、制御部３７による非オゾン水供給ポンプ１９、オゾン水供給ポンプ３３、及び循環ポンプ３０の制御方法を説明する。制御部３７は、非オゾン水供給ポンプ１９、オゾン水供給ポンプ３３、及び循環ポンプ３０を全て駆動させた上で、以下のようにそれぞれのポンプを制御する。 Here, a method of controlling the non-ozonated water supply pump 19, the ozonated water supply pump 33, and the circulation pump 30 by the control unit 37 will be described. After driving all of the non-ozonized water supply pump 19, the ozonated water supply pump 33, and the circulation pump 30, the control unit 37 controls each pump as follows.
　まず、非オゾン水供給流路２１から循環流路２９へ供給する非オゾン水の流量と、循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量とが同一になるように、非オゾン水供給ポンプ１９及びオゾン水供給ポンプ３３の少なくとも一方を制御する。すなわち、制御部３７は非オゾン水供給流量測定手段２０の値とオゾン水供給流量測定手段３４の値とが等しくなるように、非オゾン水供給ポンプ１９及びオゾン水供給ポンプ３３の少なくとも一方を制御する。例えば、制御部３７は、オゾン水供給流量測定手段３４の値が高くなった場合は、非オゾン水供給流量測定手段２０の値も高くなるよう非オゾン水供給ポンプ１９の出力を上げ、反対にオゾン水供給流量測定手段３４の値が低くなった場合は、非オゾン水供給流量測定手段２０の値も低くなるよう非オゾン水供給ポンプ１９の出力を下げるように制御する。 First, the flow rate of the non-ozonated water supplied from the non-ozonated water supply channel 21 to the circulation channel 29 and the flow rate of the ozonated water 28 supplied from the circulation channel 29 to the ozonated water supply channel 35 are made equal. , controls at least one of the non-ozonated water supply pump 19 and the ozonated water supply pump 33 . That is, the control unit 37 controls at least one of the non-ozonated water supply pump 19 and the ozonated water supply pump 33 so that the value of the non-ozonated water supply flow rate measuring means 20 and the value of the ozonized water supply flow rate measuring means 34 become equal. do. For example, when the value of the ozonated water supply flow rate measuring means 34 increases, the control unit 37 increases the output of the non-ozonated water supply pump 19 so that the value of the non-ozonated water supply flow rate measuring means 20 also increases. When the value of the ozonated water supply flow rate measuring means 34 becomes low, the output of the non-ozonated water supply pump 19 is controlled to be lowered so that the value of the non-ozonated water supply flow rate measuring means 20 also becomes low.
　そして、制御部３７は、循環流路２９におけるオゾン水２８の流量は、循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量より高くなるように、循環ポンプ３０を制御する。すなわち、制御部３７は循環流量測定手段３１の値がオゾン水供給流量測定手段３４の値より高くなるように、循環ポンプ３０及び前記オゾン水供給ポンプ３３の少なくとも一方を制御する。例えば、制御部３７は、オゾン水供給流量測定手段３４の値が循環流量測定手段３１の値より上昇した場合は、循環ポンプ３０の出力を上げるように制御する。 Then, the control unit 37 controls the circulation pump 30 so that the flow rate of the ozonized water 28 in the circulation flow path 29 is higher than the flow rate of the ozonated water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35. . That is, the control unit 37 controls at least one of the circulation pump 30 and the ozone water supply pump 33 so that the value of the circulation flow rate measuring means 31 becomes higher than the value of the ozone water supply flow rate measuring means 34 . For example, when the value of the ozone water supply flow rate measuring means 34 is higher than the value of the circulation flow rate measuring means 31, the control section 37 controls the output of the circulation pump 30 to be increased.
　制御部３７は、非オゾン水を循環流路２９へ供給したことにより、循環流路２９を循環するオゾン水２８が希釈され、循環流路２９内の溶存オゾン濃度測定手段３２により測定された溶存オゾン濃度の値が予め設定された閾値未満になった場合は、次のように制御する。制御部３７は、非オゾン水供給ポンプ１９及びオゾン水供給ポンプ３３を停止させ、切替部３６のオゾン水供給流路３５側を閉じ、切替部１８を閉じる。そして、制御部３７は循環ポンプ３０を継続して起動させる。これにより、制御部３７は、溶存オゾン濃度測定手段３２により測定された溶存オゾン濃度の値が予め設定された閾値未満である場合、循環流路２９への非オゾン水の供給、及びオゾン水２８の濾過膜３への供給を停止し、循環流路２９内でのオゾン水２８の生成、及び循環流路２９内におけるオゾン水２８の循環のみを実施する。これにより、循環流路２９を循環するオゾン水２８の溶存オゾン濃度は徐々に上昇する。その後、溶存オゾン濃度測定手段３２の値が予め設定された閾値以上になった場合、制御部３７は切替部３６のオゾン水供給流路３５側を開け、切替部１８を開けて、非オゾン水供給ポンプ１９及びオゾン水供給ポンプ３３を起動させる。つまり、制御部３７は、循環流路２９への非オゾン水の供給、循環流路２９内でのオゾン水２８の生成、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給を同時に行い、濾過膜３の逆洗浄を再開させる。これにより、オゾン水２８の溶存オゾン濃度を予め設定された閾値以上に保つことができる。 The controller 37 dilutes the ozonized water 28 circulating in the circulation flow path 29 by supplying the non-ozonated water to the circulation flow path 29 , and reduces the dissolved ozone concentration measured by the dissolved ozone concentration measuring means 32 in the circulation flow path 29 . When the ozone concentration value is less than the preset threshold value, the following control is performed. The control unit 37 stops the non-ozonated water supply pump 19 and the ozonated water supply pump 33 , closes the ozonated water supply channel 35 side of the switching unit 36 , and closes the switching unit 18 . Then, the controller 37 continues to activate the circulation pump 30 . Thereby, when the value of the dissolved ozone concentration measured by the dissolved ozone concentration measuring means 32 is less than the preset threshold value, the control unit 37 supplies the non-ozonated water to the circulation flow path 29 and the ozonated water 28 to the filtration membrane 3, and only the generation of the ozonized water 28 in the circulation flow path 29 and the circulation of the ozonated water 28 in the circulation flow path 29 are performed. As a result, the dissolved ozone concentration of the ozone water 28 circulating in the circulation flow path 29 gradually increases. After that, when the value of the dissolved ozone concentration measuring means 32 becomes equal to or higher than a preset threshold value, the control unit 37 opens the ozonated water supply channel 35 side of the switching unit 36, opens the switching unit 18, and The supply pump 19 and the ozone water supply pump 33 are started. That is, the control unit 37 supplies non-ozonated water to the circulation flow path 29, generates the ozonated water 28 in the circulation flow path 29, circulates the ozonated water 28 in the circulation flow path 29, and filters the ozonated water 28. The feed to the membrane 3 is carried out at the same time and the backwashing of the filtration membrane 3 is resumed. As a result, the dissolved ozone concentration of the ozone water 28 can be maintained at a preset threshold value or higher.
　オゾン水２８を用いた濾過膜３の洗浄処理の時間は、特に限定されず、濾過膜３に付着した汚濁物質の量などに応じて適宜設定すればよい。一般的には、濾過膜３の洗浄処理の時間は６０分以下が好ましい。洗浄時間は短い方が好ましく、洗浄時間が長いとオゾンガス供給部２３の稼働時間やポンプの稼働時間が長くなるため、ランニングコストが増大する。また、被処理水１の膜処理を中断する時間も長くなるため、膜濾過水１７量が低下する。 The time for the cleaning treatment of the filtration membrane 3 using the ozone water 28 is not particularly limited, and may be appropriately set according to the amount of contaminants adhering to the filtration membrane 3 and the like. In general, it is preferable that the filtration membrane 3 is washed for 60 minutes or less. The shorter the cleaning time, the better. If the cleaning time is long, the operating time of the ozone gas supply unit 23 and the operating time of the pump become longer, resulting in an increase in running cost. In addition, since the time during which the membrane treatment of the water 1 to be treated is interrupted also becomes longer, the amount of the membrane-filtered water 17 decreases.
　オゾン水２８の濾過膜面積当たりの供給水量である膜面透過流束は、特に限定されず、濾過膜３末端まで充填可能な流束を確保できればよい。具体的に、オゾン水２８の膜面透過流束は、１ＬＭＨ（Ｌ／ｍ２／ｈ）以上６０ＬＭＨ以下が好ましい。オゾン水２８の膜面透過流束が６０ＬＭＨより高い場合、濾過膜３に付着した汚濁物質の分解速度よりもオゾン水２８の供給速度の方が速くなるため、汚染物質と反応しなかったオゾン水２８が濾過膜３の外側へ流出する。その結果、オゾン水２８の使用量が必要以上に増加し、濾過膜３の洗浄に要するコストが増大する可能性がある。オゾン水２８の膜面透過流束が１ＬＭＨより低い場合、オゾン水２８が濾過膜３末端まで充填されず、濾過膜３に付着した汚濁物質を分解できなくなったり、搬送中に濃度が低下したりする可能性がある。本実施の形態に係る濾過膜３の洗浄処理はオゾン水２８を濾過膜３内に通水した後、オゾン水２８をそのまま濾過膜３内で保持する洗浄方法、又は濾過膜３をオゾン水２８に浸漬して保持する洗浄方法などを用いることができる。 The membrane surface permeation flux, which is the amount of water supplied per filtration membrane area of the ozonized water 28, is not particularly limited as long as the flux that can be filled up to the end of the filtration membrane 3 can be secured. Specifically, the membrane surface permeation flux of the ozone water 28 is preferably 1 LMH (L/m2/h) or more and 60 LMH or less. When the membrane surface permeation flux of the ozonated water 28 is higher than 60 LMH, the supply speed of the ozonated water 28 is faster than the decomposition speed of the contaminants adhering to the filtration membrane 3, so the ozonized water that did not react with the contaminants 28 flows out of the filter membrane 3 . As a result, the amount of ozonated water 28 used increases more than necessary, and the cost required for cleaning the filtration membrane 3 may increase. If the membrane surface permeation flux of the ozonated water 28 is lower than 1 LMH, the ozonized water 28 is not filled up to the ends of the filtration membrane 3, and contaminants adhering to the filtration membrane 3 cannot be decomposed, or the concentration decreases during transportation. there's a possibility that. The cleaning treatment of the filtration membrane 3 according to the present embodiment is a cleaning method in which the ozone water 28 is passed through the filtration membrane 3 and then the ozone water 28 is retained in the filtration membrane 3 as it is, or the filtration membrane 3 is washed with the ozone water 28 . It is possible to use a cleaning method such as immersing in and holding.
　濾過膜３の洗浄処理後に濾過膜３から排出されるオゾン水２８は、膜分離槽２内に排出し、膜濾過処理に用いる被処理水１として利用することができる。或いは、逆流洗浄後に濾過膜３から排出されるオゾン水２８は、処理済液として別途回収して処理してもよい。 The ozone water 28 discharged from the filtration membrane 3 after the filtration membrane 3 has been washed can be discharged into the membrane separation tank 2 and used as the water to be treated 1 for membrane filtration. Alternatively, the ozone water 28 discharged from the filtration membrane 3 after back washing may be separately collected and treated as a treated liquid.
　濾過膜３の洗浄処理を終了する場合、制御部３７は、非オゾン水供給ポンプ１９、循環ポンプ３０、及びオゾン水供給ポンプ３３を停止させる（ステップＳ１０）。そして、制御部３７は切替部１１の循環流路２９側を閉じ、切替部１８を閉じる（ステップＳ１１）。これにより、オゾン水２８の供給及び循環を停止する。そして、制御部３７は、図３に示すＳ１及びＳ２を実施し、被処理水１の膜濾過処理を再開する。これにより、被処理水１の膜濾過処理を連続的且つ効率的に行うことができる。 When ending the cleaning process of the filtration membrane 3, the control unit 37 stops the non-ozonated water supply pump 19, the circulation pump 30, and the ozonated water supply pump 33 (step S10). Then, the control unit 37 closes the circulation flow path 29 side of the switching unit 11 and closes the switching unit 18 (step S11). As a result, the supply and circulation of the ozone water 28 are stopped. Then, the control unit 37 performs S1 and S2 shown in FIG. 3 and restarts the membrane filtration treatment of the water 1 to be treated. Thereby, the membrane filtration process of the to-be-processed water 1 can be performed continuously and efficiently.
　本実施の形態における水処理装置１００の効果を従来の水処理装置及び比較例の水処理装置と比較して説明する。図５は実施の形態１の比較例の水処理装置の概略図である。従来の水処理装置では、濾過膜３を洗浄するオゾン水２８を生成し貯水するためのオゾン水生成塔の設置が必要であった。そのため、従来の水処理装置では、オゾン水生成塔を設置するためのスペースの確保及びイニシャルコストが課題であった。 The effect of the water treatment device 100 of the present embodiment will be described in comparison with the conventional water treatment device and the water treatment device of the comparative example. FIG. 5 is a schematic diagram of a water treatment apparatus as a comparative example of Embodiment 1. FIG. A conventional water treatment apparatus requires installation of an ozonated water generating tower for generating and storing the ozonized water 28 for cleaning the filtration membrane 3 . Therefore, in the conventional water treatment apparatus, securing a space for installing the ozonated water generating tower and the initial cost were problems.
　図５に示す比較例の水処理装置は、膜濾過水槽１６と濾過膜３とを接続し、膜濾過水槽１６から膜濾過水１７を濾過膜３に供給するための流路に、オゾンガス供給部２３を接続し、流路内においてオゾン水２８の生成を行い、生成したオゾン水２８を濾過膜３へ供給する。比較例の水処理装置は、流路内においてオゾン水２８の生成を行うため、従来の水処理装置のオゾン水生成塔を設置する必要がない。しかしながら、比較例の水処理装置は、例えばオゾンガス供給部２３から濾過膜３までの距離が短い場合、又は濾過膜３へのオゾン水２８の供給流量が高い場合に、オゾンガス供給部２３から流路内に供給されたオゾンガスが膜濾過水１７に十分に溶解される前に濾過膜３に送水され、オゾン水２８中の溶存オゾン濃度が予め設定された値まで上昇することなく濾過膜３へ供給される虞がある。そのため、比較例の水処理装置は濾過膜３の洗浄効果が低減するという課題がある。 The water treatment apparatus of the comparative example shown in FIG. 23 are connected, ozone water 28 is generated in the channel, and the generated ozone water 28 is supplied to the filtration membrane 3 . Since the water treatment apparatus of the comparative example generates the ozonized water 28 in the flow path, it is not necessary to install an ozonated water generating tower of the conventional water treatment apparatus. However, in the water treatment apparatus of the comparative example, for example, when the distance from the ozone gas supply part 23 to the filtration membrane 3 is short, or when the supply flow rate of the ozone water 28 to the filtration membrane 3 is high, the flow path from the ozone gas supply part 23 Before the ozone gas supplied inside is sufficiently dissolved in the membrane filtered water 17, it is sent to the filtration membrane 3, and the dissolved ozone concentration in the ozone water 28 is supplied to the filtration membrane 3 without increasing to a preset value. There is a risk of being Therefore, the water treatment apparatus of the comparative example has a problem that the cleaning effect of the filtration membrane 3 is reduced.
　これに対し、本実施の形態における水処理装置１００は、図１に示すように、非オゾン水供給流路２１から供給された非オゾン水にオゾンガス供給部２３により供給されたオゾンガスが溶解されてオゾン水２８が生成される流路であり、生成されたオゾン水２８を循環させる循環ポンプ３０が設けられた循環流路２９と、循環流路２９への非オゾン水の供給、循環流路２９内でのオゾン水２８の生成、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給を同時に行うように、非オゾン水供給ポンプ１９、循環ポンプ３０、及びオゾン水供給ポンプ３３を制御する制御部３７を備える。これにより、本実施の形態における水処理装置１００は、従来の水処理装置が備えるオゾン水生成塔を設ける必要がない。そして、本実施の形態における水処理装置１００及び上述の比較例の水処理装置において、オゾンガス供給部２３から濾過膜３までの距離が等しく、濾過膜３へのオゾン水２８の供給流量が等しい場合に、本実施の形態における水処理装置１００は比較例の水処理装置よりもオゾン水２８の溶存オゾン濃度の維持を容易に行うことができる。そのため、本実施の形態における水処理装置１００は比較例の水処理装置よりも濾過膜３の洗浄効果の低減を抑制することができる。 On the other hand, in the water treatment apparatus 100 according to the present embodiment, as shown in FIG. A circulation flow path 29, which is a flow path for generating ozonated water 28 and is provided with a circulation pump 30 for circulating the generated ozonated water 28; The non-ozonated water supply pump 19, the circulation pump 30, and the A control unit 37 for controlling the ozone water supply pump 33 is provided. As a result, the water treatment apparatus 100 according to the present embodiment does not need to be provided with an ozonated water generation tower provided in conventional water treatment apparatuses. Then, in the water treatment apparatus 100 of the present embodiment and the water treatment apparatus of the comparative example described above, when the distance from the ozone gas supply unit 23 to the filtration membrane 3 is equal and the supply flow rate of the ozone water 28 to the filtration membrane 3 is equal Moreover, the water treatment apparatus 100 of the present embodiment can more easily maintain the dissolved ozone concentration of the ozone water 28 than the water treatment apparatus of the comparative example. Therefore, the water treatment apparatus 100 in the present embodiment can suppress reduction in the cleaning effect of the filtration membrane 3 more than the water treatment apparatus of the comparative example.
　すなわち、本実施の形態の水処理装置１００は循環流路２９内において非オゾン水にオゾンガスを溶解させてオゾン水２８を生成する。そして、本実施の形態の水処理装置１００は、循環流路２９への非オゾン水の供給、循環流路２９内でのオゾン水２８の生成、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給を同時に行うことにより、濾過膜３の洗浄処理に必要な容量のオゾン水２８を貯水する必要がない。これにより、従来の水処理装置において必要であったオゾン水生成塔の設置を不要とすることができる。 That is, the water treatment apparatus 100 of the present embodiment dissolves ozone gas in the non-ozonized water in the circulation flow path 29 to generate the ozonated water 28 . The water treatment apparatus 100 of the present embodiment supplies non-ozonated water to the circulation flow path 29, generates ozonated water 28 in the circulation flow path 29, circulates the ozonated water 28 in the circulation flow path 29, and the ozonized water 28 to the filtration membrane 3 at the same time, it is not necessary to store the ozonated water 28 in a volume necessary for cleaning the filtration membrane 3 . This eliminates the need to install an ozonated water generating tower, which is required in conventional water treatment equipment.
　また、上述の比較例の水処理装置のように、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給が同時に行われない場合、同じ量のオゾンガスがオゾンガス供給部２３から流路に供給されたとすれば、オゾンガス供給部２３から濾過膜３までの距離、及び濾過膜３へのオゾン水２８の供給流量によっては、オゾンガスが十分に溶解されず、オゾン水２８中の溶存オゾン濃度が予め設定された値まで上昇することなく濾過膜３へ供給される虞がある。本実施の形態の水処理装置１００は、循環流路２９への非オゾン水の供給、循環流路２９内でのオゾン水２８の生成、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給を同時に行う。すなわち、循環流路２９において生成されたオゾン水２８の全量が濾過膜３へ供給されるのではなく、循環流路２９において生成されたオゾン水２８の一部は濾過膜３へ供給され、一部は循環流路２９を循環する。このように、生成されたオゾン水２８の一部は循環流路２９を循環することにより、オゾン水２８が濾過膜３へ供給されるまでの時間が長くなるため、オゾン水２８中の溶存オゾン濃度を予め設定された値まで上昇させることが容易になる。そのため、本実施の形態における水処理装置１００は比較例の水処理装置よりも濾過膜３の洗浄効果の低減を抑制することができる。 Moreover, when the circulation of the ozone water 28 in the circulation flow path 29 and the supply of the ozone water 28 to the filtration membrane 3 are not performed at the same time as in the water treatment apparatus of the comparative example described above, the same amount of ozone gas is used as ozone gas. If the ozone gas is supplied from the supply unit 23 to the flow path, the ozone gas may not be sufficiently dissolved depending on the distance from the ozone gas supply unit 23 to the filtration membrane 3 and the flow rate of the ozone water 28 supplied to the filtration membrane 3. There is a risk that the dissolved ozone concentration in 28 will be supplied to the filtration membrane 3 without increasing to a preset value. The water treatment apparatus 100 of the present embodiment supplies non-ozonated water to the circulation passage 29, generates ozonated water 28 in the circulation passage 29, circulates the ozonated water 28 in the circulation passage 29, and ozonates the water. The water 28 is supplied to the filtration membrane 3 at the same time. That is, not all of the ozone water 28 generated in the circulation flow path 29 is supplied to the filtration membrane 3, but a part of the ozone water 28 generated in the circulation flow path 29 is supplied to the filtration membrane 3, The part circulates through the circulation channel 29 . In this way, part of the generated ozonated water 28 circulates through the circulation flow path 29 , which lengthens the time until the ozonated water 28 is supplied to the filtration membrane 3 . It becomes easier to increase the concentration to a preset value. Therefore, the water treatment apparatus 100 in the present embodiment can suppress reduction in the cleaning effect of the filtration membrane 3 more than the water treatment apparatus of the comparative example.
　また、非オゾン水供給流路２１から循環流路２９へ供給する非オゾン水の流量が循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量よりも多い場合、循環流路２９を循環するオゾン水２８の溶存オゾン濃度が上昇しにくい。また、越流水流路２７によって循環流路２９から排出されるオゾン水２８が増水するためオゾン水２８が無駄に消費される。逆に、循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量が非オゾン水供給から循環流路２９へ供給する非オゾン水の流量よりも多い場合、循環流路２９内を循環するオゾン水２８が枯渇し循環ポンプ３０が空運転をする虞がある。そこで、制御部３７は、非オゾン水供給流路２１から循環流路２９へ供給する非オゾン水の流量と、循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量とが同一になるように、非オゾン水供給ポンプ１９及びオゾン水供給ポンプ３３の少なくとも一方を制御する。これにより、循環流路２９に流入する非オゾン水の流量と、循環流路２９から流出するオゾン水２８の流量が等しくなるため、循環流路２９を循環するオゾン水２８の容量を一定に保つことができる。 Further, when the flow rate of the non-ozonated water supplied from the non-ozonated water supply channel 21 to the circulation channel 29 is greater than the flow rate of the ozonized water 28 supplied from the circulation channel 29 to the ozonized water supply channel 35, the circulation channel The dissolved ozone concentration of the ozone water 28 circulating through 29 is less likely to increase. In addition, since the ozonized water 28 discharged from the circulation flow path 29 is increased by the overflow water flow path 27, the ozonated water 28 is wasted. Conversely, when the flow rate of the ozonated water 28 supplied from the circulation channel 29 to the ozonated water supply channel 35 is greater than the flow rate of the non-ozonated water supplied from the non-ozonated water supply to the circulation channel 29, The ozonized water 28 circulating through the water is depleted, and the circulation pump 30 may run dry. Therefore, the controller 37 controls the flow rate of the non-ozonated water supplied from the non-ozonated water supply channel 21 to the circulation channel 29 and the flow rate of the ozonized water 28 supplied from the circulation channel 29 to the ozonated water supply channel 35. At least one of the non-ozonated water supply pump 19 and the ozonated water supply pump 33 is controlled to be the same. As a result, the flow rate of the non-ozonized water flowing into the circulation flow path 29 and the flow rate of the ozonated water 28 flowing out of the circulation flow path 29 become equal, so that the volume of the ozonized water 28 circulating through the circulation flow path 29 is kept constant. be able to.
　また、制御部３７は、循環流路２９におけるオゾン水２８の流量は、循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量より高くなるように、循環ポンプ３０及びオゾン水供給ポンプ３３の少なくとも一方を制御する。ここで、本実施の形態の循環流路２９におけるオゾン水２８の流量をｘ、循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量をｙとする。ｘ＞ｙである。 In addition, the control unit 37 controls the circulation pump 30 and the ozone water so that the flow rate of the ozonized water 28 in the circulation flow path 29 is higher than the flow rate of the ozonized water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35 . At least one of the supply pumps 33 is controlled. Here, let x be the flow rate of the ozonated water 28 in the circulation flow path 29 of the present embodiment, and y be the flow rate of the ozonated water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35 . x > y.
　ここで、制御部３７は、循環流路２９におけるオゾン水２８の流量、及び循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量をともにｘに制御したと仮定する。この場合、オゾン水供給流路３５へ供給するオゾン水２８の流量が高いためオゾン水２８の溶存オゾン濃度の低減は抑制できるが、オゾン水２８の使用量は増加する。これに対し、本実施の形態の水処理装置１００は、オゾン水供給流路３５へ供給するオゾン水２８の流量ｙは循環流路２９におけるオゾン水２８の流量ｘよりも低いため、オゾン水２８の使用量を低減することができる。 Here, it is assumed that the control unit 37 controls both the flow rate of the ozonated water 28 in the circulation flow path 29 and the flow rate of the ozonated water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35 to x. In this case, since the flow rate of the ozonized water 28 supplied to the ozonized water supply channel 35 is high, the reduction of the dissolved ozone concentration of the ozonated water 28 can be suppressed, but the amount of the ozonized water 28 used increases. In contrast, in the water treatment apparatus 100 of the present embodiment, the flow rate y of the ozonized water 28 supplied to the ozonized water supply channel 35 is lower than the flow rate x of the ozonized water 28 in the circulation channel 29. can reduce the amount used.
　次に、制御部３７は、循環流路２９におけるオゾン水２８の流量、及び循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量をともにｙに制御したと仮定する。この場合、オゾン水２８の流量が低いため、オゾン水２８の使用量を低減することができるが、濾過膜３にオゾン水が供給された際にオゾン水２８の溶存オゾン濃度は低減する虞がある。これに対し、本実施の形態の水処理装置１００は、循環流路２９におけるオゾン水２８の流量ｘは、循環流路２９からオゾン水供給流路３５へ供給するオゾン水２８の流量ｙより高いため、オゾン水２８中の溶存オゾン濃度の低下を抑制することができる。 Next, it is assumed that the control unit 37 controls both the flow rate of the ozonized water 28 in the circulation flow path 29 and the flow rate of the ozonated water 28 supplied from the circulation flow path 29 to the ozonized water supply flow path 35 to y. In this case, since the flow rate of the ozonized water 28 is low, the amount of the ozonized water 28 used can be reduced. be. In contrast, in the water treatment apparatus 100 of the present embodiment, the flow rate x of the ozonated water 28 in the circulation flow path 29 is higher than the flow rate y of the ozonated water 28 supplied from the circulation flow path 29 to the ozonated water supply flow path 35. Therefore, a decrease in dissolved ozone concentration in the ozone water 28 can be suppressed.
　また、制御部３７は、溶存オゾン濃度測定手段３２により測定された溶存オゾン濃度の値が予め設定された閾値未満である場合、循環流路２９への非オゾン水の供給、及びオゾン水２８の濾過膜３への供給を停止し、循環流路２９内でのオゾン水２８の生成、及び循環流路２９内におけるオゾン水２８の循環のみを実施する。そして、制御部３７は、溶存オゾン濃度測定手段３２により測定された溶存オゾン濃度の値が予め設定された閾値以上となった場合に、循環流路２９への非オゾン水の供給、及びオゾン水２８の濾過膜３への供給を再開する。これにより、オゾン水２８の溶存オゾン濃度を予め設定された閾値以上に保つことができる。 Further, when the value of the dissolved ozone concentration measured by the dissolved ozone concentration measuring means 32 is less than a preset threshold value, the control unit 37 supplies the non-ozonated water to the circulation flow path 29 and the ozonated water 28. The supply to the filtration membrane 3 is stopped, and only the generation of the ozonated water 28 within the circulation flow path 29 and the circulation of the ozonated water 28 within the circulation flow path 29 are performed. Then, when the value of the dissolved ozone concentration measured by the dissolved ozone concentration measuring means 32 becomes equal to or higher than a preset threshold value, the control unit 37 supplies the non-ozonated water to the circulation flow path 29 and the ozonated water. The supply to the filtration membrane 3 of 28 is resumed. As a result, the dissolved ozone concentration of the ozone water 28 can be maintained at a preset threshold value or higher.
　また、濾過膜３の孔径が微小である場合、オゾン水２８に未溶解のオゾンガスが濾過膜３の細孔を透過しないため、未溶解のオゾンガスが濾過膜３を透過せず流路内でガスロックを起こす虞がある。そこで、本実施の形態の水処理装置１００は、循環流路２９に接続され、循環流路２９において溶解されなかったオゾンガスを循環流路２９から排出するオゾンガス排除部２６を備える。これにより、オゾン水２８に未溶解のオゾンガスを循環流路２９から排出できるので、ガスロックを防止することができる。 Further, when the pore diameter of the filtration membrane 3 is very small, the ozone gas undissolved in the ozone water 28 does not permeate the pores of the filtration membrane 3. Locking may occur. Therefore, the water treatment apparatus 100 of the present embodiment includes an ozone gas removal unit 26 connected to the circulation flow path 29 and discharging the ozone gas that has not been dissolved in the circulation flow path 29 from the circulation flow path 29 . As a result, the ozone gas that is not dissolved in the ozone water 28 can be discharged from the circulation flow path 29, thereby preventing gas lock.
　また、水処理装置１００は、オゾン水２８を濾過膜３へ供給しながら非オゾン水を循環流路２９へ供給する場合、オゾン水２８及び非オゾン水の供給開始のタイミングが必ずしも一致しない虞がある。例えば、オゾン水２８の濾過膜３への供給開始よりも、非オゾン水の循環流路２９への供給開始の方が早い場合を考える。この場合、循環流路２９内の水量が一時的に循環流路２９の最大容量を超え、流路、ポンプ、及び切替部に負荷が生じる。そこで、水処理装置１００は、循環流路２９に接続され、循環流路２９内において予め設定された水量を超えるオゾン水２８が循環する場合に、オゾン水２８を循環流路２９から排除する越流水流路２７を設ける。これにより、循環流路２９の水量が循環流路２９の最大容量を一時的に超える場合に、循環流路２９を循環するオゾン水２８を循環流路２９から排出することができる。そして、越流水流路２７は、循環流路２９においてオゾンガス排除部２６よりも低い水位に設けられる。これにより、循環流路２９内のオゾン水２８が増水した場合に、オゾンガス排除部２６にオゾン水２８が混入することを防止できる。 Further, when the water treatment apparatus 100 supplies the non-ozonated water to the circulation flow path 29 while supplying the ozonated water 28 to the filtration membrane 3, there is a possibility that the timings of starting the supply of the ozonized water 28 and the non-ozonated water do not always coincide. be. For example, consider a case where the supply of non-ozonated water to the circulation flow path 29 is started earlier than the supply of the ozonated water 28 to the filtration membrane 3 is started. In this case, the amount of water in the circulation flow path 29 temporarily exceeds the maximum capacity of the circulation flow path 29, causing loads on the flow path, the pump, and the switching section. Therefore, the water treatment apparatus 100 is connected to the circulation flow path 29, and when the ozonized water 28 exceeding the preset water amount circulates in the circulation flow path 29, the ozonized water 28 is removed from the circulation flow path 29. A running water flow path 27 is provided. As a result, the ozone water 28 circulating in the circulation channel 29 can be discharged from the circulation channel 29 when the amount of water in the circulation channel 29 temporarily exceeds the maximum capacity of the circulation channel 29 . The overflow water channel 27 is provided at a water level lower than that of the ozone gas removing section 26 in the circulation channel 29 . As a result, it is possible to prevent the ozonated water 28 from entering the ozone gas removing portion 26 when the ozonized water 28 in the circulation flow path 29 increases.
　また、本実施の形態の水処理装置１００は、非オゾン水として膜濾過水１７を用いる。これにより、非オゾン水を貯水するための水槽を新たに設ける必要がない。 Also, the water treatment apparatus 100 of the present embodiment uses the membrane filtered water 17 as the non-ozonated water. This eliminates the need to newly provide a water tank for storing non-ozonated water.
実施の形態２．
　実施の形態２における濾過膜洗浄装置を備える水処理装置１００について図６を用いて説明する。図６は実施の形態２の水処理装置１００の概略図である。実施の形態１では、濾過膜３を洗浄する洗浄水はオゾン水２８である例を示した。本実施の形態では濾過膜３を洗浄する洗浄水は、オゾン水２８、及びオゾン以外の薬剤を含有する洗浄水の少なくとも２種類の薬剤を用いる例を説明する。本実施の形態の濾過膜洗浄装置を備える水処理装置１００の基本的な構成は、実施の形態１の濾過膜洗浄装置を備える水処理装置１００と同じであるため、相違点のみ説明する。また、実施の形態１の濾過膜洗浄装置を備える水処理装置１００と同様の構成については同一符号が付されている。 Embodiment 2.
A water treatment apparatus 100 including a filtration membrane cleaning apparatus according to Embodiment 2 will be described with reference to FIG. FIG. 6 is a schematic diagram of the water treatment device 100 of Embodiment 2. As shown in FIG. Embodiment 1 shows an example in which the washing water for washing the filtration membrane 3 is the ozone water 28 . In the present embodiment, an example will be described in which at least two types of chemicals, ie, ozone water 28 and cleaning water containing chemicals other than ozone, are used as cleaning water for cleaning the filtration membrane 3 . Since the basic configuration of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of the present embodiment is the same as that of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of Embodiment 1, only differences will be described. Further, the same reference numerals are assigned to the same configurations as those of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of Embodiment 1. As shown in FIG.
　以下では、オゾン水２８を第一の洗浄水２８、オゾン以外の薬剤を含有する洗浄水を第二の洗浄水３８と称する。第二の洗浄水３８に含有される薬剤の種類は１種類に限定されない。 Hereinafter, the ozone water 28 is referred to as the first cleaning water 28, and the cleaning water containing chemicals other than ozone is referred to as the second cleaning water 38. The type of chemical contained in the second washing water 38 is not limited to one type.
　本実施の形態の濾過膜洗浄装置を備える水処理装置１００は、洗浄流路４３、第二の洗浄水３８を貯水する洗浄水槽３９を備える。 A water treatment apparatus 100 equipped with the filter membrane cleaning apparatus of the present embodiment includes a cleaning channel 43 and a cleaning water tank 39 for storing second cleaning water 38 .
　洗浄流路４３は、濾過膜３と洗浄水槽３９とを接続する流路である。図６では、洗浄流路４３の濾過膜３から切替部４２までの流路が膜濾過流路４及びオゾン水供給流路３５と共有である例を示している。洗浄流路４３は、洗浄水槽３９に貯水された第二の洗浄水３８を濾過膜３へ供給するための洗浄ポンプ４０、洗浄流路４３を流れる第二の洗浄水３８の流量を測定する洗浄流量測定手段４１を有する。 The cleaning channel 43 is a channel that connects the filtration membrane 3 and the cleaning water tank 39 . FIG. 6 shows an example in which the flow path from the filtration membrane 3 to the switching portion 42 of the cleaning flow path 43 is shared with the membrane filtration flow path 4 and the ozone water supply flow path 35 . The cleaning channel 43 includes a cleaning pump 40 for supplying the second cleaning water 38 stored in the cleaning water tank 39 to the filtration membrane 3 and a cleaning pump for measuring the flow rate of the second cleaning water 38 flowing through the cleaning channel 43 . It has flow rate measuring means 41 .
　洗浄水槽３９に貯水された第二の洗浄水３８の薬剤の種類は、オゾン以外の有機物又は無機物を分解可能な物質であれば特に限定されず、当該技術分野において公知の物質を用いることができる。有機物を分解可能な薬剤の例として、次亜塩素酸ナトリウム、過酸化水素、水酸化ナトリウムなどが挙げられる。その中でも第二の洗浄水３８の薬剤の種類は、薬剤が安価であり、濃度維持も容易な次亜塩素酸ナトリウムが好ましい。また、第二の洗浄水３８の薬剤の種類は、単独又は２種以上を組み合わせてもよい。有機物を分解可能な薬剤を２種類以上組み合わせる場合、第一の薬剤は水素電極を用いて測定された標準酸化還元電位（２５℃）が好ましくは２．０Ｖ未満であり、第二の薬剤は水素電極を用いて測定された標準酸化還元電位（２５℃）が好ましくは２．０Ｖ以上である。具体的には、第一の薬剤として次亜塩素酸ナトリウム、第二の薬剤としてオゾンを含有する洗浄水を用いることが好ましい。 The type of chemical used in the second washing water 38 stored in the washing water tank 39 is not particularly limited as long as it is a substance capable of decomposing organic or inorganic substances other than ozone, and substances known in the art can be used. . Examples of agents capable of decomposing organic matter include sodium hypochlorite, hydrogen peroxide, and sodium hydroxide. Among them, sodium hypochlorite is preferable as the type of chemical for the second washing water 38 because the chemical is inexpensive and the concentration can be easily maintained. Further, the types of chemicals in the second washing water 38 may be used singly or in combination of two or more. When combining two or more agents capable of decomposing organic matter, the first agent preferably has a standard oxidation-reduction potential (25°C) of less than 2.0 V measured using a hydrogen electrode, and the second agent is hydrogen. A standard oxidation-reduction potential (25° C.) measured using an electrode is preferably 2.0 V or more. Specifically, it is preferable to use washing water containing sodium hypochlorite as the first chemical and ozone as the second chemical.
　また、無機物を分解可能な物質は、例えば塩酸、硫酸、硝酸等の無機酸、シュウ酸、クエン酸等の有機酸である。これらも、単独又は２種以上を組み合わせて用いてもよい。有機物を分解可能な物質と無機物を分解可能な物質を２種以上組み合わせて用いてもよい。その場合、どちらを第一の薬剤又は第二の薬剤として用いるかは限定されない。例えば、有機物を分解可能な物質を第一の薬剤として用いた場合は無機物を分解可能な物質を第二の薬剤とする。無機物を分解可能な物質を第一の薬剤として用いた場合は有機物を分解可能な物質を第二の薬剤として用いればよい。 In addition, substances that can decompose inorganic substances are, for example, inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, and organic acids such as oxalic acid and citric acid. These may also be used singly or in combination of two or more. Two or more substances capable of decomposing organic substances and substances capable of decomposing inorganic substances may be used in combination. In that case, there is no limitation as to which one is used as the first drug or the second drug. For example, when a substance capable of decomposing organic substances is used as the first chemical, a substance capable of decomposing inorganic substances is used as the second chemical. When a substance capable of decomposing inorganic substances is used as the first chemical, a substance capable of decomposing organic substances may be used as the second chemical.
　第二の洗浄水３８中の薬剤濃度は、特に限定されない。例えば有機物を分解可能な物質を用いる場合、次亜塩素酸ナトリウム（有効塩素濃度）は１．０ｇ／Ｌ以上５．０ｇ／Ｌ以下、水酸化ナトリウムは１．０ｇ／Ｌ以上４．０ｇ／Ｌ以下が好ましい。無機物を分解可能な物質を用いる場合、塩酸、硫酸、硝酸は１．０ｇ／Ｌ以上１０．０ｇ／Ｌ以下、シュウ酸は１．０ｇ／Ｌ以上２．０ｇ／Ｌ以下、クエン酸は１ｇ／Ｌ以上１０ｇ／Ｌ以下が好ましい。薬剤濃度が上述の範囲よりも低いと、濾過膜３に付着した汚濁物質の分解に時間を要し、洗浄水２８の使用量の増大に伴い薬剤タンクの容量も増大する。一方、薬剤濃度が上述の範囲よりも高いと、薬剤の使用量が多くなるため、薬剤に要するコストが増大する。 The drug concentration in the second washing water 38 is not particularly limited. For example, when using a substance capable of decomposing organic matter, sodium hypochlorite (effective chlorine concentration) is 1.0 g/L or more and 5.0 g/L or less, and sodium hydroxide is 1.0 g/L or more and 4.0 g/L. The following are preferred. When using a substance capable of decomposing inorganic matter, hydrochloric acid, sulfuric acid, and nitric acid are 1.0 g/L or more and 10.0 g/L or less, oxalic acid is 1.0 g/L or more and 2.0 g/L or less, and citric acid is 1 g/L. L or more and 10 g/L or less is preferable. If the chemical concentration is lower than the above range, it takes time to decompose contaminants adhering to the filtration membrane 3, and as the amount of washing water 28 used increases, the capacity of the chemical tank also increases. On the other hand, if the concentration of the drug is higher than the above range, the amount of the drug to be used will increase, resulting in an increase in the cost required for the drug.
　第二の洗浄水３８を用いた濾過膜３の洗浄時間は、特に限定されず、濾過膜３に付着した汚濁物質の量などに応じて適宜設定すればよい。一般的には、次亜塩素酸ナトリウムを用いる場合は９０分以下、シュウ酸やクエン酸を用いる場合は５分以上７分以下が好ましい。第二の洗浄水３８を用いた濾過膜３の洗浄時間は短い方が好ましく、洗浄時間が長くなると、被処理水１の膜処理を中断する時間も長くなるため、膜濾過水量が低下する。 The time period for washing the filtration membrane 3 with the second washing water 38 is not particularly limited, and may be appropriately set according to the amount of contaminants adhering to the filtration membrane 3 and the like. In general, when using sodium hypochlorite, it is preferably 90 minutes or less, and when using oxalic acid or citric acid, it is preferably 5 minutes or more and 7 minutes or less. The cleaning time of the filtration membrane 3 using the second cleaning water 38 is preferably short, and if the cleaning time is long, the membrane treatment of the water 1 to be treated is interrupted for a long time, resulting in a decrease in the amount of membrane filtered water.
　第二の洗浄水３８の膜面積当たりの供給水量である膜面透過流束は、特に限定されない。一般的には、濾過膜３末端まで充填可能な流束を確保できればよい。具体的には、次亜塩素酸ナトリウムを用いる場合は、６ＬＭＨ（Ｌ／ｍ２／ｈ）以下が好ましい。膜面透過流束が高すぎると、第二の洗浄水３８の必要量の増大に伴い薬剤に要するコストが増大したり、薬剤タンクの容量が増大したりする。膜面透過流束が低すぎると、第二の洗浄水３８が濾過膜３末端まで充填されず、濾過膜３に付着した汚濁物質を分解できなくなる。 The membrane surface permeation flux, which is the amount of water supplied per membrane area of the second wash water 38, is not particularly limited. In general, it suffices if a flux that can be filled up to the end of the filtration membrane 3 can be secured. Specifically, when sodium hypochlorite is used, it is preferably 6 LMH (L/m 2 /h) or less. If the membrane surface permeation flux is too high, the required amount of the second washing water 38 increases, resulting in an increase in the cost required for the chemicals and an increase in the capacity of the chemical tank. If the membrane surface permeation flux is too low, the second wash water 38 will not be filled up to the end of the filtration membrane 3, and contaminants adhering to the filtration membrane 3 will not be decomposed.
　全てのポンプ及び切替部は制御部３７に接続されている。また、全ての流量測定手段および圧力計１４の測定結果は制御部３７に送信される。制御部３７は、全てのポンプ及び切替部の動作を制御する。また、制御部３７はオゾン供給部の動作を制御する。 All pumps and switching units are connected to the control unit 37. Also, the measurement results of all the flow rate measuring means and the pressure gauge 14 are sent to the control section 37 . The control unit 37 controls operations of all pumps and switching units. Also, the control unit 37 controls the operation of the ozone supply unit.
　本実施の形態の濾過膜３の洗浄方法は、第二の洗浄水３８を濾過膜３内に通水した後、第二の洗浄水３８をそのまま濾過膜３内で保持する洗浄方法や、濾過膜３を第二の洗浄水３８に浸漬して保持する洗浄方法などを用いることができる。 The method for washing the filtration membrane 3 of the present embodiment includes a washing method in which the second washing water 38 is passed through the filtration membrane 3 and then the second washing water 38 is held as it is in the filtration membrane 3, A cleaning method of immersing and holding the membrane 3 in the second cleaning water 38 or the like can be used.
　次に、本実施の形態の水処理装置１００を用いた水処理方法について説明する。ここでは、まず第二の洗浄水３８を用いて濾過膜３の洗浄処理したのちに、第一の洗浄水２８であるオゾン水２８を用いて濾過膜３の洗浄処理を実施する例を説明する。膜濾過処理及び第一の洗浄水２８であるオゾン水２８を用いて濾過膜３の洗浄処理を実施する方法は実施の形態１と同様であるため、第二の洗浄水３８を用いて濾過膜３の洗浄処理する方法について説明する。図７は実施の形態２の濾過膜３の洗浄方法を示すフローチャートであり、第二の洗浄水３８を用いた濾過膜３の洗浄方法のみ示している。 Next, a water treatment method using the water treatment device 100 of this embodiment will be described. Here, an example will be described in which the filtration membrane 3 is first washed with the second washing water 38, and then the filtration membrane 3 is washed with the ozone water 28, which is the first washing water 28. . Since the method of carrying out the membrane filtration treatment and the washing treatment of the filtration membrane 3 using the ozone water 28 as the first washing water 28 is the same as in Embodiment 1, the second washing water 38 is used to clean the filtration membrane 3. 3, the cleaning method will be described. FIG. 7 is a flow chart showing the cleaning method of the filtration membrane 3 of Embodiment 2, and shows only the cleaning method of the filtration membrane 3 using the second washing water 38 .
　制御部３７は、膜濾過処理を行っていた場合は膜濾過ポンプ１２を停止する（ステップＳ２０）。次に、制御部３７は切替部４２の膜濾過水流路１５側を閉じ、洗浄流路４３側を開く（ステップＳ２１）。そして、制御部３７は洗浄ポンプ４０を起動させ（ステップＳ２２）、洗浄流路４３を介して第二の洗浄水３８を濾過膜３へ供給し、濾過膜３の洗浄処理を開始する。第二の洗浄水３８を用いた濾過膜３の洗浄処理を終了する場合、制御部３７は、洗浄ポンプ４０を停止し（ステップＳ２３）、切替部４２の洗浄流路４３側を閉じ（ステップＳ２４）、第二の洗浄水３８の供給を停止する。 The control unit 37 stops the membrane filtration pump 12 when the membrane filtration process is being performed (step S20). Next, the control unit 37 closes the membrane filtered water channel 15 side of the switching unit 42 and opens the cleaning channel 43 side (step S21). Then, the control unit 37 activates the washing pump 40 (step S22), supplies the second washing water 38 to the filtration membrane 3 through the washing flow path 43, and starts washing the filtration membrane 3. FIG. When finishing the cleaning process of the filtration membrane 3 using the second cleaning water 38, the control unit 37 stops the cleaning pump 40 (step S23) and closes the cleaning channel 43 side of the switching unit 42 (step S24). ), the supply of the second wash water 38 is stopped.
　また、制御部３７は、上述の第二の洗浄水３８を用いて濾過膜３の洗浄処理と同時に、第一の洗浄水２８であるオゾン水２８の生成及び循環を実施してもよい。これにより、第二の洗浄水３８を用いて濾過膜３の洗浄処理を実施したのちに、速やかに第一の洗浄水２８であるオゾン水２８を用いて濾過膜３の洗浄処理を開始することができる。そして、制御部３７は、実施の形態１で説明したオゾン水２８を用いて濾過膜３の洗浄処理を実施する。 In addition, the control unit 37 may generate and circulate ozone water 28 as the first cleaning water 28 at the same time as cleaning the filtration membrane 3 using the second cleaning water 38 described above. As a result, after the filtration membrane 3 is washed with the second washing water 38, the washing treatment of the filtration membrane 3 with the ozone water 28, which is the first washing water 28, can be started immediately. can be done. Then, the control unit 37 performs the cleaning process of the filtration membrane 3 using the ozone water 28 described in the first embodiment.
　実施の形態１と同様、本実施の形態における水処理装置１００は、非オゾン水供給流路２１から供給された非オゾン水にオゾンガス供給部２３により供給されたオゾンガスが溶解されてオゾン水２８が生成される流路であり、生成されたオゾン水２８を循環させる循環ポンプ３０が設けられた循環流路２９と、循環流路２９への非オゾン水の供給、循環流路２９内でのオゾン水２８の生成、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給を同時に行うように、非オゾン水供給ポンプ１９、循環ポンプ３０、及びオゾン水供給ポンプ３３を制御する制御部３７とを備える。これにより、本実施の形態における水処理装置１００は、従来の水処理装置が備えるオゾン水生成塔を設けることなく必要がない。そして、本実施の形態における水処理装置１００及び図５に示す比較例の水処理装置において、オゾンガス供給部２３から濾過膜３までの距離が等しく、濾過膜３へのオゾン水２８の供給流量が等しい場合に 、本実施の形態における水処理装置１００は図５に示す比較例の水処理装置よりもよりもオゾン水２８の溶存オゾン濃度の維持を容易に行うことができる。そのため、本実施の形態における水処理装置１００は図５に示す比較例の水処理装置よりも濾過膜３の洗浄効果の低減を抑制することができる。 As in Embodiment 1, in the water treatment apparatus 100 of the present embodiment, the ozone gas supplied from the ozone gas supply unit 23 is dissolved in the non-ozonated water supplied from the non-ozonated water supply channel 21 to form the ozone water 28. A circulation channel 29 provided with a circulation pump 30 for circulating the generated ozone water 28, a supply of non-ozonated water to the circulation channel 29, and ozone in the circulation channel 29. A non-ozonated water supply pump 19, a circulation pump 30, and an ozonated water supply pump are provided so as to simultaneously generate the water 28, circulate the ozonized water 28 in the circulation flow path 29, and supply the ozonated water 28 to the filtration membrane 3. and a control unit 37 for controlling 33 . As a result, the water treatment apparatus 100 according to the present embodiment does not need to be provided with an ozonated water generation tower provided in the conventional water treatment apparatus. In the water treatment apparatus 100 of the present embodiment and the water treatment apparatus of the comparative example shown in FIG. When equal, the water treatment apparatus 100 of the present embodiment can more easily maintain the dissolved ozone concentration of the ozone water 28 than the water treatment apparatus of the comparative example shown in FIG. Therefore, the water treatment apparatus 100 according to the present embodiment can suppress reduction in the cleaning effect of the filtration membrane 3 more than the water treatment apparatus of the comparative example shown in FIG.
　また、本実施の形態における水処理装置１００は、オゾン以外の薬剤を含有する第二の洗浄水３８を貯水する洗浄水槽３９と、前記洗浄水槽３９に貯水された第二の洗浄水３８を濾過膜３へ供給するための洗浄ポンプ４０が設けられ、濾過膜３と洗浄水槽３９とを接続する洗浄流路４３とをさらに備える。これにより、オゾン水２８である第一の洗浄水２８と第二の洗浄水３８を併用して濾過膜３の洗浄処理を実施することができる。 Further, the water treatment apparatus 100 in the present embodiment includes a cleaning water tank 39 storing second cleaning water 38 containing chemicals other than ozone, and filtering the second cleaning water 38 stored in the cleaning water tank 39. A wash pump 40 is provided for feeding the membrane 3 and further comprises a wash channel 43 connecting the filtration membrane 3 and the wash water bath 39 . As a result, the filtration membrane 3 can be washed using both the first washing water 28 and the second washing water 38 which are the ozone water 28 .
　なお、制御部３７は、第二の洗浄水３８を膜濾過水１７により希釈しながら濾過膜３の洗浄処理を実施してもよい。具体的には、制御部３７は切替部１１の膜濾過水流路１５側を閉じ、濾過膜３側及び循環流路２９側を開く。そして、制御部３７は、切替部４２の洗浄流路４３側を開き、切替部１８及び切替部３６を開く。そして、制御部３７は非オゾン水供給ポンプ１９、循環ポンプ３０、及び洗浄ポンプ４０を起動させる。これにより、第二の洗浄水３８を膜濾過水１７により希釈しながら濾過膜３の洗浄処理を実施することが可能である。また、制御部３７は、洗浄流量測定手段４１の値及び非オゾン水供給流量測定手段２０の値に応じて、洗浄ポンプ４０及び非オゾン水供給ポンプ１９の少なくとも一方を調整することで、濾過膜３に供給する希釈した第二の洗浄水３８の濃度及び流量を調整することができる。 Note that the control unit 37 may wash the filtration membrane 3 while diluting the second washing water 38 with the membrane filtered water 17 . Specifically, the control unit 37 closes the membrane filtered water channel 15 side of the switching unit 11 and opens the filtration membrane 3 side and the circulation channel 29 side. Then, the control unit 37 opens the cleaning channel 43 side of the switching unit 42 and opens the switching unit 18 and the switching unit 36 . The controller 37 then activates the non-ozonated water supply pump 19 , the circulation pump 30 and the cleaning pump 40 . This makes it possible to wash the filtration membrane 3 while diluting the second washing water 38 with the membrane filtered water 17 . In addition, the control unit 37 adjusts at least one of the cleaning pump 40 and the non-ozonated water supply pump 19 according to the value of the cleaning flow rate measuring means 41 and the value of the non-ozonated water supply flow rate measuring means 20, so that the filtration membrane The concentration and flow rate of the diluted second wash water 38 supplied to 3 can be adjusted.
　また、本実施の形態では、第一の洗浄水２８と第二の洗浄水３８を併用して濾過膜３の洗浄処理を実施する例を示したが、洗浄水の種類は２種類に限られない。例えば、オゾンを含有するオゾン水２８、有機物を分解可能な物質を含有する洗浄水、及び無機物を含有する洗浄水を併用してもよい。また、複数の種類の洗浄水を用いて濾過膜３の洗浄処理する際、濾過膜３の洗浄処理を実施する洗浄水の順番は特に限定されない。 Further, in the present embodiment, an example in which the filtration membrane 3 is washed using both the first washing water 28 and the second washing water 38 is shown, but the types of washing water are limited to two. do not have. For example, ozonized water 28 containing ozone, cleaning water containing a substance capable of decomposing organic substances, and cleaning water containing inorganic substances may be used in combination. Further, when the filtration membrane 3 is washed using a plurality of types of washing water, the order of the washing waters for washing the filtration membrane 3 is not particularly limited.
　また、洗浄流路４３の濾過膜３から切替部４２までの流路は、第二の洗浄水３８及び膜濾過水１７を均一に混合する例えばスタティックミキサー等の手段を備えてもよい。 In addition, the channel from the filtration membrane 3 to the switching part 42 of the cleaning channel 43 may be provided with means such as a static mixer for uniformly mixing the second cleaning water 38 and the membrane-filtered water 17 .
実施の形態３．
　実施の形態３における濾過膜洗浄装置を備える水処理装置１００について図８を用いて説明する。図８は実施の形態３の水処理装置１００の概略図である。実施の形態１及び実施の形態２では、非オゾン水として膜濾過水１７を用いる例を説明した。本実施の形態では、非オゾン水として膜濾過水１７以外の清澄水４５を用いる例を説明する。本実施の形態の濾過膜洗浄装置を備える水処理装置１００の基本的な構成は、実施の形態１又は実施の形態２の濾過膜洗浄装置を備える水処理装置１００と同じであるため、相違点のみ説明する。また、実施の形態１及び実施の形態２の濾過膜洗浄装置を備える水処理装置１００と同様の構成については同一符号が付されている。 Embodiment 3.
A water treatment apparatus 100 including a filtration membrane cleaning apparatus according to Embodiment 3 will be described with reference to FIG. FIG. 8 is a schematic diagram of the water treatment device 100 of Embodiment 3. As shown in FIG. Embodiment 1 and Embodiment 2 explained the example using the membrane filtered water 17 as non-ozonated water. In the present embodiment, an example of using clarified water 45 other than membrane-filtered water 17 as non-ozonated water will be described. Since the basic configuration of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of the present embodiment is the same as that of the water treatment apparatus 100 including the filtration membrane cleaning apparatus of Embodiment 1 or Embodiment 2, there are differences only explained. Further, the same reference numerals are given to the same configurations as those of the water treatment apparatus 100 having the filtration membrane cleaning apparatus of Embodiments 1 and 2. As shown in FIG.
　本実施の形態の水処理装置１００は、膜濾過水１７以外の清澄水４５が貯水された清澄水槽４４を備え、非オゾン水供給流路２１は清澄水槽４４と循環流路２９とを接続する。膜濾過水１７以外の清澄水４５は、オゾン水２８を生成するに当たり最低限の水質を得ることができるものであればよく、例えば水道水、工水、イオン交換水、純水、及び超純水の少なくともいずれか一つである。 The water treatment apparatus 100 of the present embodiment includes a clarification water tank 44 in which clarified water 45 other than the membrane filtered water 17 is stored, and the non-ozonated water supply channel 21 connects the clarification water tank 44 and the circulation channel 29. . The clarified water 45 other than the membrane-filtered water 17 may be any water that can obtain the minimum water quality for producing the ozonized water 28. For example, tap water, industrial water, ion-exchanged water, pure water, and ultrapure At least one of water.
　本実施の形態の濾過膜３の洗浄処理は、実施の形態１又は実施の形態２に記載の濾過膜３の洗浄処理において非オゾン水として清澄水４５を用いる点以外は同様の方法である。 The cleaning treatment of the filtration membrane 3 of the present embodiment is the same as the cleaning treatment of the filtration membrane 3 described in the first or second embodiment, except that clarified water 45 is used as the non-ozonated water.
　実施の形態１と同様、本実施の形態における水処理装置１００は、非オゾン水供給流路２１から供給された非オゾン水にオゾンガス供給部２３により供給されたオゾンガスが溶解されてオゾン水２８が生成される流路であり、生成されたオゾン水２８を循環させる循環ポンプ３０が設けられた循環流路２９と、循環流路２９への非オゾン水の供給、循環流路２９内でのオゾン水２８の生成、循環流路２９内におけるオゾン水２８の循環、及びオゾン水２８の濾過膜３への供給を同時に行うように、非オゾン水供給ポンプ１９、循環ポンプ３０、及びオゾン水供給ポンプ３３を制御する制御部３７とを備える。これにより、本実施の形態における水処理装置１００は、従来の水処理装置が備えるオゾン水生成塔を設けることなく必要がない。そして、本実施の形態における水処理装置１００及び図５に示す比較例の水処理装置において、オゾンガス供給部２３から濾過膜３までの距離が等しく、濾過膜３へのオゾン水２８の供給流量が等しい場合に 、本実施の形態における水処理装置１００は図５に示す比較例の水処理装置よりもよりもオゾン水２８の溶存オゾン濃度の維持を容易に行うことができる。そのため、本実施の形態における水処理装置１００は図５に示す比較例の水処理装置よりも濾過膜３の洗浄効果の低減を抑制することができる。 As in Embodiment 1, in the water treatment apparatus 100 of the present embodiment, the ozone gas supplied from the ozone gas supply unit 23 is dissolved in the non-ozonated water supplied from the non-ozonated water supply channel 21 to form the ozone water 28. A circulation channel 29 provided with a circulation pump 30 for circulating the generated ozone water 28, a supply of non-ozonated water to the circulation channel 29, and ozone in the circulation channel 29. A non-ozonated water supply pump 19, a circulation pump 30, and an ozonated water supply pump are provided so as to simultaneously generate the water 28, circulate the ozonized water 28 in the circulation flow path 29, and supply the ozonated water 28 to the filtration membrane 3. and a control unit 37 for controlling 33 . As a result, the water treatment apparatus 100 according to the present embodiment does not need to be provided with an ozonated water generation tower provided in the conventional water treatment apparatus. In the water treatment apparatus 100 of the present embodiment and the water treatment apparatus of the comparative example shown in FIG. When equal, the water treatment apparatus 100 of the present embodiment can more easily maintain the dissolved ozone concentration of the ozone water 28 than the water treatment apparatus of the comparative example shown in FIG. Therefore, the water treatment apparatus 100 according to the present embodiment can suppress reduction in the cleaning effect of the filtration membrane 3 more than the water treatment apparatus of the comparative example shown in FIG.
　また、膜濾過水１７の水質は被処理水１の水質の影響を受ける場合がある。そのため、非オゾン水として膜濾過水１７を用いると、膜濾過水１７に吹き込んだオゾンガスと膜濾過水１７中に溶解していた物質が反応し、膜濾過水１７に溶解できるオゾンが少なくなる場合がある。これにより、オゾン水２８の溶存オゾン濃度を上昇させるために大量のオゾンガスが必要になる、及び溶存オゾン濃度を予め設定された濃度に上昇させるまでに時間を要する虞がある。 Also, the water quality of the membrane filtered water 17 may be affected by the water quality of the water 1 to be treated. Therefore, if the membrane-filtered water 17 is used as the non-ozonated water, the ozone gas blown into the membrane-filtered water 17 reacts with the substances dissolved in the membrane-filtered water 17, and the amount of ozone that can be dissolved in the membrane-filtered water 17 decreases. There is As a result, a large amount of ozone gas is required to raise the dissolved ozone concentration of the ozone water 28, and it may take time to raise the dissolved ozone concentration to a preset concentration.
　また、実施の形態２において第二の洗浄水３８を膜濾過水１７により希釈する場合も、薬剤と膜濾過水１７中に溶解していた物質が反応し、膜濾過水１７に溶解する薬剤濃度が低下し、濾過膜３の洗浄効果が低減する虞がある。 Further, when the second washing water 38 is diluted with the membrane-filtered water 17 in Embodiment 2, the drug reacts with the substance dissolved in the membrane-filtered water 17, and the drug concentration dissolved in the membrane-filtered water 17 increases. may decrease, and the cleaning effect of the filtration membrane 3 may decrease.
　そこで、本実施の形態の水処理装置１００は、非オゾン水として膜濾過水１７以外の清澄水４５を用いる。具体的には、水道水、工水、イオン交換水、純水、及び超純水の少なくともいずれか一つである。これにより、非オゾン水として膜濾過水１７を用いた場合と比較して、オゾン水２８の生成及び第二の洗浄水３８の希釈を効率的かつ安定的に行うことが可能できる。 Therefore, the water treatment apparatus 100 of the present embodiment uses clarified water 45 other than the membrane-filtered water 17 as non-ozonated water. Specifically, it is at least one of tap water, industrial water, ion-exchanged water, pure water, and ultrapure water. This makes it possible to efficiently and stably generate the ozonized water 28 and dilute the second wash water 38 compared to the case of using the membrane-filtered water 17 as the non-ozonated water.
　なお、上述の実施の形態に示した構成は、一例を示すものであり、別の公知の技術と組み合わせることも可能である。また、実施の形態同士を組み合わせることも可能であるし、要旨を逸脱しない範囲で、構成の一部を省略、変更することも可能である。 It should be noted that the configuration shown in the above-described embodiment is an example, and can be combined with another known technique. Further, it is possible to combine the embodiments, and it is also possible to omit or change a part of the configuration without departing from the gist of the invention.
１　被処理水、２　膜分離槽、３　濾過膜、４　膜濾過流路、５　被処理水流路、６　膜面曝気ブロワー、７　空気供給配管、８　散気装置、９　汚泥引抜ポンプ、１０　汚泥引抜流路、１１　切替部、１２　膜濾過ポンプ、１３　膜濾過水流量測定手段、１４　圧力計、１５　膜濾過水流路、１６　膜濾過水槽、１７　膜濾過水、１８　切替部、１９　非オゾン水供給ポンプ、２０　非オゾン水供給流量測定手段、２１　非オゾン水供給流路、２２　オゾン水生成部　２３　オゾンガス供給部、２４　オゾンガス供給配管、２５　散気装置、２６　オゾンガス排除部、２７　越流水流路、２８　オゾン水（第一の洗浄水）、２９　循環流路、３０　循環ポンプ、３１　循環流量測定手段、３２　溶存オゾン濃度測定手段、３３　オゾン水供給ポンプ、３４　オゾン水供給流量測定手段、３５　オゾン水供給流路、３６　切替部、３７　制御部、３８　第二の洗浄水、３９　洗浄水槽、４０　洗浄ポンプ、４１　洗浄流量測定手段、４２　切替部、４３　洗浄流路、４４　清澄水槽、４５　清澄水、１００　水処理装置 1 Water to be treated, 2 Membrane separation tank, 3 Filtration membrane, 4 Membrane filtration channel, 5 Water channel to be treated, 6 Membrane surface aeration blower, 7 Air supply pipe, 8 Air diffuser, 9 Sludge extraction pump, 10 Sludge extraction Flow path 11 Switching section 12 Membrane filtration pump 13 Membrane filtered water flow rate measuring means 14 Pressure gauge 15 Membrane filtered water flow path 16 Membrane filtered water tank 17 Membrane filtered water 18 Switching section 19 Non-ozonated water supply pump 20 non-ozonated water supply flow rate measuring means 21 non-ozonated water supply channel 22 ozonated water generator 23 ozone gas supply part 24 ozone gas supply pipe 25 air diffuser 26 ozone gas removal part 27 overflow water channel 28 Ozonated water (first cleaning water), 29 Circulating flow path, 30 Circulating pump, 31 Circulating flow rate measuring means, 32 Dissolved ozone concentration measuring means, 33 Ozone water supply pump, 34 Ozonated water supply flow rate measuring means, 35 Ozonated water supply Flow path, 36 Switching section, 37 Control section, 38 Second cleaning water, 39 Cleaning water tank, 40 Cleaning pump, 41 Cleaning flow rate measuring means, 42 Switching section, 43 Cleaning flow path, 44 Clarification water tank, 45 Clarification water, 100 water treatment equipment

Claims (10)

  1. 　オゾンガスを供給するオゾンガス供給部と、
    　オゾンを含有しない水である非オゾン水を供給する非オゾン水供給ポンプが設けられた非オゾン水供給流路と、
    　前記非オゾン水供給流路から供給された非オゾン水に前記オゾンガス供給部により供給された前記オゾンガスが溶解されてオゾン水が生成される流路であり、生成された前記オゾン水を循環させる循環ポンプが設けられ、前記オゾンガス供給部及び前記非オゾン水供給流路が接続された循環流路と、
    　前記循環流路を循環している前記オゾン水の一部を濾過膜へ供給するオゾン水供給ポンプが設けられ、前記循環流路に接続されたオゾン水供給流路と、
    　前記循環流路への前記非オゾン水の供給、前記循環流路内での前記オゾン水の生成、前記循環流路内における前記オゾン水の循環、及び前記オゾン水の前記濾過膜への供給を同時に行うように、前記非オゾン水供給ポンプ、前記循環ポンプ、及び前記オゾン水供給ポンプを制御する制御部と、
    を備える濾過膜洗浄装置。     an ozone gas supply unit that supplies ozone gas;
    a non-ozonated water supply channel provided with a non-ozonated water supply pump for supplying non-ozonized water, which is water containing no ozone;
    A flow path for generating ozone water by dissolving the ozone gas supplied by the ozone gas supply unit into the non-ozonated water supplied from the non-ozonated water supply path, and circulating the generated ozone water. a circulation channel provided with a pump and connected to the ozone gas supply unit and the non-ozonated water supply channel;
    an ozonized water supply channel connected to the circulation channel, the ozonated water supply pump being provided to supply part of the ozonized water circulating in the circulation channel to the filtration membrane;
    supply of the non-ozonated water to the circulation channel, generation of the ozonated water in the circulation channel, circulation of the ozonated water in the circulation channel, and supply of the ozonated water to the filtration membrane a control unit that controls the non-ozonated water supply pump, the circulation pump, and the ozonated water supply pump to perform simultaneously;
    Filtration membrane cleaning device.
  2. 　前記制御部は、前記非オゾン水供給流路から前記循環流路へ供給する前記非オゾン水の流量と、前記循環流路から前記オゾン水供給流路へ供給する前記オゾン水の流量とが同一になるように、前記非オゾン水供給ポンプ及び前記オゾン水供給ポンプの少なくとも一方を制御することを特徴とする請求項１に記載の濾過膜洗浄装置。 The control unit sets the flow rate of the non-ozonated water supplied from the non-ozonated water supply channel to the circulation channel to be the same as the flow rate of the ozonized water supplied from the circulation channel to the ozonated water supply channel. 2. The filtration membrane cleaning device according to claim 1, wherein at least one of the non-ozonated water supply pump and the ozonated water supply pump is controlled so that
  3. 　前記制御部は、前記循環流路における前記オゾン水の流量は、前記循環流路から前記オゾン水供給流路へ供給する前記オゾン水の流量より高くなるように、前記循環ポンプ及び前記オゾン水供給ポンプの少なくとも一方を制御することを特徴とする請求項１又は請求項２に記載の濾過膜洗浄装置。 The control unit controls the circulation pump and the ozonated water supply so that the flow rate of the ozonized water in the circulation flow path is higher than the flow rate of the ozonized water supplied from the circulation flow path to the ozonized water supply flow path. 3. The filtration membrane cleaning device according to claim 1, wherein at least one of the pumps is controlled.
  4. 　前記循環流路は、前記循環流路における前記オゾン水の溶存オゾン濃度を測定する溶存オゾン濃度測定手段をさらに備え、
    　前記制御部は前記溶存オゾン濃度が予め設定された閾値未満である場合、前記循環流路への前記非オゾン水の供給、及び前記オゾン水の前記濾過膜への供給を停止し、前記循環流路内での前記オゾン水の生成、及び前記循環流路内における前記オゾン水の循環を実施し、前記溶存オゾン濃度が予め設定された前記閾値以上になった場合に、前記循環流路への前記非オゾン水の供給、及び前記オゾン水の前記濾過膜への供給を再開することを特徴とする請求項１から３のいずれか一項に記載の濾過膜洗浄装置。     The circulation channel further comprises dissolved ozone concentration measuring means for measuring the dissolved ozone concentration of the ozone water in the circulation channel,
    When the dissolved ozone concentration is less than a preset threshold value, the control unit stops supplying the non-ozonized water to the circulation channel and supplying the ozonated water to the filtration membrane, The ozonated water is generated in the passage, and the ozonized water is circulated in the circulation passage, and when the dissolved ozone concentration reaches or exceeds the preset threshold value, the ozonated water is supplied to the circulation passage. The filtration membrane cleaning apparatus according to any one of claims 1 to 3, wherein the supply of the non-ozonated water and the supply of the ozonated water to the filtration membrane are resumed.
  5. 　前記循環流路に接続され、前記循環流路内において予め設定された水量を超える前記オゾン水が循環する場合に、前記オゾン水を前記循環流路から排除するための越流水流路をさらに備えることを特徴とする請求項1から４のいずれか一項に記載の濾過膜洗浄装置。 It further comprises an overflow water channel connected to the circulation channel for removing the ozonated water from the circulation channel when the ozonated water exceeding a preset amount of water circulates in the circulation channel. 5. The filtration membrane cleaning device according to any one of claims 1 to 4, characterized in that:
  6. 　前記循環流路に接続され、前記循環流路において溶解されなかった前記オゾンガスを前記循環流路から排出するオゾンガス排除部をさらに備えることを特徴とする請求項1から５のいずれか一項に記載の濾過膜洗浄装置。 6. The ozone gas removal unit according to claim 1, further comprising an ozone gas removal unit connected to the circulation flow path for discharging the ozone gas that has not been dissolved in the circulation flow path from the circulation flow path. Filtration membrane cleaning equipment.
  7. 　前記オゾン以外の薬剤を含有する洗浄水を貯水する洗浄水槽と、
    　前記洗浄水槽に貯水された前記洗浄水を前記濾過膜へ供給するための洗浄ポンプが設けられ、前記濾過膜と前記洗浄水槽とを接続する洗浄流路とをさらに備えることを特徴とする請求項1から６のいずれか一項に記載の濾過膜洗浄装置。     a cleaning water tank storing cleaning water containing chemicals other than the ozone;
    3. The apparatus further comprises a washing pump for supplying the washing water stored in the washing water tank to the filtration membrane, and further comprising a washing flow path connecting the filtration membrane and the washing water tank. 7. The filtration membrane cleaning device according to any one of 1 to 6.
  8. 　前記非オゾン水は膜濾過水、水道水、工水、イオン交換水、純水、及び超純水の少なくともいずれか一つであることを特徴とする請求項1から７のいずれか一項に記載の濾過膜洗浄装置。 8. The method according to any one of claims 1 to 7, wherein the non-ozonated water is at least one of membrane filtered water, tap water, industrial water, ion-exchanged water, pure water, and ultrapure water. Filtration membrane cleaning device as described.
  9. 　被処理水を膜濾過処理する濾過膜を有する膜分離槽と、
    　前記膜分離槽により膜濾過処理された膜濾過水を貯水する膜濾過水槽と、
    　オゾンガスを供給するオゾンガス供給部と、
    　オゾンを含有しない水である非オゾン水を供給する非オゾン水供給ポンプが設けられた非オゾン水供給流路と、
    　前記非オゾン水供給流路から供給された非オゾン水に前記オゾンガス供給部により供給された前記オゾンガスが溶解されてオゾン水が生成される流路であり、生成された前記オゾン水を循環させる循環ポンプが設けられ、前記オゾンガス供給部及び前記非オゾン水供給流路が接続された循環流路と、
    　前記循環流路を循環している前記オゾン水の一部を前記濾過膜へ供給するオゾン水供給ポンプが設けられ、前記循環流路に接続されたオゾン水供給流路と、
    　前記循環流路への前記非オゾン水の供給、前記循環流路内での前記オゾン水の生成、前記循環流路内における前記オゾン水の循環、及び前記オゾン水の前記濾過膜への供給を同時に行うように、前記非オゾン水供給ポンプ、前記循環ポンプ、及び前記オゾン水供給ポンプを制御する制御部と、
    を備える水処理装置。     a membrane separation tank having a filtration membrane for membrane filtration of water to be treated;
    a membrane filtration water tank for storing membrane filtered water that has been subjected to membrane filtration by the membrane separation tank;
    an ozone gas supply unit that supplies ozone gas;
    a non-ozonated water supply channel provided with a non-ozonated water supply pump for supplying non-ozonated water, which is water containing no ozone;
    A flow path for generating ozone water by dissolving the ozone gas supplied by the ozone gas supply unit into the non-ozonated water supplied from the non-ozonated water supply path, and circulating the generated ozone water. a circulation channel provided with a pump and connected to the ozone gas supply unit and the non-ozonated water supply channel;
    an ozonized water supply channel connected to the circulation channel, provided with an ozonized water supply pump that supplies part of the ozonized water circulating in the circulation channel to the filtration membrane;
    supply of the non-ozonated water to the circulation channel, generation of the ozonated water in the circulation channel, circulation of the ozonated water in the circulation channel, and supply of the ozonated water to the filtration membrane a control unit that controls the non-ozonated water supply pump, the circulation pump, and the ozonated water supply pump to perform simultaneously;
    water treatment equipment.
  10. 　オゾンを含有しない水である非オゾン水を循環流路に供給するステップと、
    　前記循環流路において前記非オゾン水にオゾンガスを溶解させてオゾン水を生成するステップと、
    　前記循環流路において前記オゾン水を循環させるステップと、
    　前記循環流路を循環している前記オゾン水の一部を濾過膜へ供給するステップと、を有し、
    　前記循環流路への前記非オゾン水の供給、前記循環流路内での前記オゾン水の生成、前記循環流路内における前記オゾン水の循環、及び前記オゾン水の前記濾過膜への供給を同時に行うことを特徴とする濾過膜洗浄方法。     a step of supplying non-ozonated water, which is water that does not contain ozone, to the circulation channel;
    a step of dissolving ozone gas in the non-ozonated water in the circulation channel to generate ozonated water;
    circulating the ozone water in the circulation channel;
    a step of supplying part of the ozonized water circulating in the circulation channel to the filtration membrane;
    supply of the non-ozonated water to the circulation channel, generation of the ozonated water in the circulation channel, circulation of the ozonated water in the circulation channel, and supply of the ozonated water to the filtration membrane A filtration membrane cleaning method characterized in that they are carried out at the same time.
PCT/JP2022/003625 2022-01-31 2022-01-31 Filtration membrane cleaning apparatus, water treatment apparatus, and filtration membrane cleaning method WO2023145082A1 (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015156242A1 (en) * 2014-04-10 2015-10-15 三菱電機株式会社 Water treatment method and water treatment apparatus each using membrane
WO2019039155A1 (en) * 2017-08-23 2019-02-28 三菱電機株式会社 Water treatment membrane cleaning apparatus and cleaning method membrane
WO2020255201A1 (en) * 2019-06-17 2020-12-24 三菱電機株式会社 Filtration membrane cleaning apparatus, filtration membrane cleaning method and water treatment system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015156242A1 (en) * 2014-04-10 2015-10-15 三菱電機株式会社 Water treatment method and water treatment apparatus each using membrane
WO2019039155A1 (en) * 2017-08-23 2019-02-28 三菱電機株式会社 Water treatment membrane cleaning apparatus and cleaning method membrane
WO2020255201A1 (en) * 2019-06-17 2020-12-24 三菱電機株式会社 Filtration membrane cleaning apparatus, filtration membrane cleaning method and water treatment system

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