WO2021192002A1 - Water treatment system - Google Patents

Water treatment system Download PDF

Info

Publication number
WO2021192002A1
WO2021192002A1 PCT/JP2020/012884 JP2020012884W WO2021192002A1 WO 2021192002 A1 WO2021192002 A1 WO 2021192002A1 JP 2020012884 W JP2020012884 W JP 2020012884W WO 2021192002 A1 WO2021192002 A1 WO 2021192002A1
Authority
WO
WIPO (PCT)
Prior art keywords
water
pipe
chemical solution
mixed
membrane
Prior art date
Application number
PCT/JP2020/012884
Other languages
French (fr)
Japanese (ja)
Inventor
祐樹 佐藤
英二 今村
野田 清治
Original Assignee
三菱電機株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 三菱電機株式会社 filed Critical 三菱電機株式会社
Priority to CN202080098624.5A priority Critical patent/CN115297949A/en
Priority to JP2020552417A priority patent/JP6877656B1/en
Priority to PCT/JP2020/012884 priority patent/WO2021192002A1/en
Publication of WO2021192002A1 publication Critical patent/WO2021192002A1/en

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D65/00Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
    • B01D65/02Membrane cleaning or sterilisation ; Membrane regeneration
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/44Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00Biological treatment of water, waste water, or sewage
    • C02F3/02Aerobic processes
    • C02F3/12Activated sludge processes
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00Technologies for wastewater treatment
    • Y02W10/10Biological treatment of water, waste water, or sewage

Definitions

  • This application relates to a water treatment system.
  • Membrane treatment using a filtration membrane is used as a method for separating suspended solids in water to be treated.
  • a filtration membrane a cylindrical or sheet-shaped microfiltration membrane and an ultrafiltration membrane are generally used.
  • a filtration method there are an external pressure filtration method in which the water to be treated flows outside the cylindrical or sheet-shaped filtration membrane and the filtered water flows inward, and an external pressure filtration method in which the water to be treated flows inside the cylindrical filtration membrane and filters outside.
  • the surface of the filter membrane in contact with the water to be treated (outer surface in the external pressure filtration method, the inner surface in the internal pressure filtration method), and the surface of the filter membrane in contact with the filtered water (external pressure filtration method).
  • pollutants adhere to the inner surface, the outer surface in the internal pressure filtration method), or the pores of the filtration membrane, causing clogging, and the filtration performance gradually deteriorates.
  • the pressure required for filtration increases, so that the membrane filtration flux (unit time, amount of membrane-filtered water per unit membrane area) also decreases. Therefore, in order to maintain the performance of the filtration membrane, it is necessary to clean the filtration membrane regularly.
  • washing water containing an oxidizing agent such as sodium hypochlorite (also called “sodium hypochlorite”) or ozone is used from the secondary side in the direction opposite to the primary side of the filtration film.
  • an oxidizing agent such as sodium hypochlorite (also called “sodium hypochlorite”) or ozone.
  • a plurality of chemical solutions for example, an alkaline substance such as sodium hypochlorite, or an acidic substance such as hydrochloric acid, sulfuric acid, and citric acid are stored in separate chemical solution tanks, and a switching valve is used to sequentially pass a plurality of wash waters through filtration.
  • a switching valve is used to sequentially pass a plurality of wash waters through filtration.
  • the filter membrane may break with the continuous use of the filter membrane, and suspended solids and dissolved organic substances in the water to be treated may flow out into the filtered water.
  • the chemical solution remaining in the pipe is removed using the wash water from which the suspended solids and dissolved organic substances in the water to be treated have flowed out, the chemical solution reacts with the suspended solids and dissolved organic substances in the washing water to increase the concentration of the chemical solution. There was a problem that it could not be maintained.
  • the present application discloses a technique for solving the above-mentioned problems, and an object of the present application is to provide a water treatment system capable of supplying a chemical solution to a filtration membrane while maintaining the concentration of a plurality of chemical solutions. ..
  • the water treatment system disclosed in the present application comprises a water tank to be treated, a membrane module installed in the water tank to be treated and having a filtration film for filtering the water to be treated, and the filtration membrane.
  • a plurality of chemical solution supply units for supplying a plurality of chemical solutions for cleaning, and filtered water filtered by the membrane module, which remains in a pipe connecting the chemical solution supply unit and the water tank to be treated.
  • a washing water tank containing washing water used for removing the chemical solution, a gas supply device for supplying the gas used for removing the chemical solution remaining in the pipe, and a gas supply device installed in the pipe and described above. It is equipped with an integrated flow meter that measures the integrated flow rate of the washing water or the gas used for removing the chemical solution.
  • a water treatment system that ends the removal of the chemical solution when the value of the integrated flow meter exceeds the capacity of the pipe in the pipe.
  • the chemical solution can be applied to the filtration membrane while maintaining the concentration of the plurality of chemical solutions.
  • FIG. 1 It is a conceptual diagram which shows the water treatment system which includes the filtration membrane cleaning apparatus which concerns on Embodiment 1.
  • FIG. 2 It is a conceptual diagram which shows the water treatment system which includes the filtration membrane cleaning apparatus which concerns on Embodiment 2.
  • FIG. 2 It is a conceptual diagram which shows the water treatment system which includes the filtration membrane cleaning apparatus which concerns on Embodiment 4.
  • FIG. 1 It is a conceptual diagram which shows the water treatment system which includes the filtration membrane cleaning apparatus which concerns on Embodiment 1.
  • Embodiment 1 relates to a water treatment system having a filter membrane cleaning device used for separating suspended solids from treated water such as water supply, sewerage, industrial water, and various wastewaters by a filter membrane.
  • a filter membrane cleaning device used for separating suspended solids from treated water such as water supply, sewerage, industrial water, and various wastewaters by a filter membrane.
  • the washing water (filtered water) is passed through the pipe to eliminate the chemical solution remaining in the pipe. This prevents different types of chemicals from mixing in the pipe and reducing the concentration.
  • the present embodiment provides a water treatment system for preventing different types of chemicals from mixing in a pipe and reducing the concentration.
  • FIG. 1 is a conceptual diagram showing a water treatment system including the filtration membrane cleaning device according to the first embodiment.
  • the water treatment system is equipped with a filtration device.
  • the filtration device includes a water tank 2 to be treated for accommodating the water to be treated 1, a membrane module 3 having a filtration film for filtering the water to be treated 1, and filtered water filtered by the membrane module 3 (as wash water 17 described later). It has a filtered water pipe 4 for discharging (used).
  • the water tank 2 to be treated is provided with a water supply pipe 5 to be treated to supply the water 1 to be treated, and the filtered water pipe 4 is provided with an integrated flow meter 13 and a second backwash valve 36 from the membrane module 3 side.
  • the first backwash valve 32, the wash water supply valve 25, the pressure gauge 14, the filter valve 15, and the filter pump 16 are provided in this order.
  • a sludge extraction pipe 6 and a sludge circulation pipe 7 are connected to the water tank 2 to be treated, and an air diffuser 8 is arranged at the bottom of the water tank 2 to be treated.
  • the sludge extraction pipe 6 is provided with a sludge extraction pump 9 for extracting sludge
  • the sludge circulation pipe 7 is provided with a sludge circulation pump 10 for circulating sludge in the water tank 2 to be treated. ..
  • a membrane surface aeration blower 12 is connected to the air diffuser 8 via an air supply pipe 11.
  • the water to be treated 1 is filtered in this filtration device, the water to be treated 1 is filtered by the membrane module 3 by opening the filtration valve 15 and activating the filtration pump 16. Then, the filtered water filtered by the membrane module 3 is discharged to the washing water tank 18 via the filtered water pipe 4.
  • the membrane module 3 is continuously filtered with the water to be treated 1, the filtration membrane in the membrane module 3 is clogged with pollutants, so that it is necessary to clean the filtration membrane. Therefore, this water treatment system is further equipped with a filtration membrane cleaning device.
  • the filter membrane cleaning device uses a method of cleaning the filter membrane using a mixed water in which the first agent is mixed with the cleaning water 17 as a chemical solution, and a mixed water in which the cleaning water 17 is mixed with the second agent as the chemical solution. It is provided with a method of cleaning the filter membrane.
  • the filtration membrane cleaning device includes a cleaning water tank 18 for accommodating the cleaning water 17, a first drug storage tank 22 for accommodating the first drug, and a second drug. It is provided with a second drug storage tank 23 for accommodating.
  • the washing water tank 18 is provided with a turbidity meter 41 and a washing water pipe 24.
  • the wash water pipe 24 is provided with a backwash pump 19 and a switching valve 20. Further, the washing water pipe 24 is branched into two, and one washing water pipe 24A is connected to the filtered water pipe 4 by the washing water supply valve 25.
  • the other wash water pipe 24B is connected to the first backwash pipe 26 and the second backwash pipe 27 at the switching valve 21.
  • the first backwash pipe 26 is connected to the first air supply pipe 39 at the first air supply valve 31, and the second backwash pipe 27 is connected to the second air supply pipe 39 at the second air supply valve 35. It is connected to the air supply pipe 40.
  • a cleaning blower 38 is provided in the first air supply pipe 39 and the second air supply pipe 40.
  • An air supply device for cleaning the filtration membrane is configured by the first air supply pipe 39, the second air supply pipe 40, and the cleaning blower 38. It should be noted that not only air but also other gases may be used, and as will be described later, the chemical solution remaining in the pipe can be eliminated by supplying the gas by the gas supply device.
  • the first chemical storage tank 22 is provided with a first chemical supply pipe 28, and the first chemical supply pipe 28 is connected to the first backwash pipe 26.
  • the second chemical storage tank 23 is provided with a second chemical supply pipe 29, and the second chemical supply pipe 29 is connected to the second backwash pipe 27.
  • the first drug supply pipe 28 is provided with a first drug supply valve 30 and a first drug supply pump 33 (which also operates as a suction device as described later), and is provided with a second drug supply pipe.
  • the 29 is provided with a second drug supply valve 34 and a second drug supply pump 37 (which also operates as a suction device as will be described later).
  • the drug supply unit is composed of the first drug storage tank 22, the first drug supply pump 33, the first drug supply pipe 28, and the first backwash pipe 26, and the second drug storage tank 23,
  • the chemical supply unit is composed of the second chemical supply pump 37, the second chemical supply pipe 29, and the second backwash pipe 27.
  • all pumps, valves, and switching valves are connected to a control device, which controls the operation of all pumps, valves, and switching valves.
  • the filtration pump 16 is first stopped, the filtration valve 15 is closed, and then the filtration membrane cleaning treatment is started.
  • the switching from the filtration treatment of the water to be treated 1 to the cleaning treatment of the filtration membrane may be controlled by the time of the filtration treatment.
  • the filtration membrane in the membrane module 3 can be pretreated. For example, by exposing the filtration membrane in the membrane module 3 to air for a certain period of time, it is possible to easily remove pollutants adhering to the surface of the filtration membrane in contact with the water to be treated 1.
  • the switching valve 20, the washing water supply valve 25, the first backwash valve 32, and the second backwash valve 36 are opened to start the backwash pump 19, and the washing water pipes 24, 24A and filtered water are started from the washing water tank 18.
  • the filter membrane may be pre-cleaned by supplying the cleaning water 17 to the membrane module 3 via the pipe 4.
  • the switching valve 20, the switching valve 21, the first chemical supply valve 30, the first air supply valve 31, the first backwash valve 32 and the second backwash valve 36 are opened to start the backwash pump 19.
  • the filter membrane may be pre-cleaned by supplying the wash water 17 from the wash water tank 18 to the membrane module 3 via the wash water pipes 24 and 24B, the first backwash pipe 26, and the filtered water pipe 4.
  • the switching valve 20, the switching valve 21, the second chemical supply valve 34, the second air supply valve 35, and the second backwash valve 36 are opened to start the backwash pump 19, and the washing water is washed from the washing water tank 18.
  • the filter membrane may be pre-cleaned by supplying the wash water 17 to the membrane module 3 via the pipes 24 and 24B, the second backwash pipe 27, and the filtered water pipe 4.
  • first air supply valve 31, the first backwash valve 32, and the second backwash valve 36 are opened to start the washing blower 38, and the first air supply pipe 39 and the first backwash pipe 26 are started.
  • the filter membrane may be pre-cleaned by supplying air to the membrane module 3 via the filtered water pipe 4.
  • the second air supply valve 35 and the second backwash valve 36 are opened to start the cleaning blower 38, and the cleaning blower 38 is started via the second air supply pipe 40, the second backwash pipe 27, and the filtered water pipe 4.
  • the filter membrane may be pre-cleaned by supplying air to the membrane module 3. Similarly, when performing these preliminary cleanings, it is possible to easily remove the pollutant substances adhering to the surface of the filtration membrane in contact with the water to be treated 1.
  • the switching valve 20 is opened to start the backwash pump 19, and the washing water 17 is connected to the first backwashing pipe 26 from the washing water tank 18 via the washing water pipes 24 and 24B and the switching valve 21.
  • the first drug supply valve 30 is opened to start the first drug supply pump 33, and the first backwash pipe is supplied from the first drug storage tank 22 via the first drug supply pipe 28.
  • the first agent is supplied to 26.
  • the washing water 17 and the first chemical are mixed in the first backwashing pipe 26, and the mixed water is generated.
  • the first backwash pipe 26 may be provided with a device (for example, a static mixer) that uniformly mixes the wash water 17 and the first chemical.
  • the mixed water containing the first chemical is supplied to the membrane module 3 via the filtered water pipe 4, and the filtered membrane in the membrane module 3 is backwashed.
  • a tank for accommodating the washing water 17 is provided in the first backwash pipe 26, the first chemical is supplied into the tank, the washing water 17 and the first chemical are uniformly mixed, and the mixed water is mixed.
  • the filtration membrane in the membrane module 3 may be backwashed by supplying the membrane module 3 with a pump.
  • the mixed water containing the first chemical discharged from the membrane module 3 after the backflow cleaning can be discharged into the water tank 2 to be treated and used as the water 1 to be treated used for the filtration treatment.
  • the mixed water containing the first chemical discharged from the membrane module 3 after the backflow cleaning may be separately collected and treated as a treated liquid.
  • the mixed water after each backwashing treatment described below can also be treated in the same manner as described above.
  • the integrated flow rate meter 13 located between the membrane module 3 and the second backwash valve 36 is used to measure the integrated flow rate in the chemical solution exclusion.
  • the value of the integrated flow meter 13 between the membrane module 3 and the second backwash valve 36 indicates that the mixed water in which the first drug is mixed with the washing water 17 as the chemical solution and the second drug in the washing water 17 as the chemical solution. It is preferable to end the chemical solution elimination step when the mixed water exceeds the capacity of the pipe at the place where the mixed water passes.
  • the capacity inside the pipe refers to the amount of chemical solution filling the inside of the pipe.
  • the viscosity of the chemical solution to be excluded is 2 cP (CENTI POISE), (mPa ⁇ s), it is twice the capacity of the pipe, and if it is 3 cP (mPa ⁇ s), the chemical solution is eliminated when it is 3 times or more the capacity of the pipe. It is more preferable to end the process. Further, the method of removing the chemical solution, the exclusion time, and the exclusion flow rate may be different between the mixed water in which the first agent is mixed with the washing water 17 and the mixed water in which the second agent is mixed in the washing water 17. ..
  • the switching valve 20, the wash water supply valve 25 and the first The backwash valve 32 and the second backwash valve 36 are opened to start the backwash pump 19, and the wash water 17 is supplied from the wash water tank 18 to the membrane module 3 via the wash water pipes 24 and 24A and the filtered water pipe 4. By doing so, the filter membrane in the membrane module 3 is backwashed.
  • the switching valve 20, the switching valve 21, the first chemical supply valve 30, the first air supply valve 31, the first backwash valve 32, and the second backwash valve 36 are opened to start the backwash pump 19.
  • the filtered membrane in the membrane module 3 is backwashed.
  • the switching valve 20, the switching valve 21, the second chemical supply valve 34, the second air supply valve 35, and the second backwash valve 36 are opened to start the backwash pump 19, and the wash water pipe is connected from the wash water tank 18.
  • the first air supply valve 31, the first backwash valve 32, and the second backwash valve 36 are opened for washing. Filtering in the membrane module 3 by activating the blower 38 and supplying air (gas) to the membrane module 3 via the first air supply pipe 39, the first backwash pipe 26, and the filtered water pipe 4. Backwash the membrane.
  • the second air supply valve 35 and the second backwash valve 36 are opened to start the cleaning blower 38, and the cleaning blower 38 is started via the second air supply pipe 40, the second backwash pipe 27, and the filtered water pipe 4.
  • the filtration membrane in the membrane module 3 is backwashed.
  • the cleaning blower 38 If the cleaning blower 38 cannot be used, after closing the cleaning water supply valve 25, the first backwash valve 32, the second backwash valve 36, the first air supply valve 31, and the first chemical supply valve 30 is opened to start the first chemical supply pump 33 (suction device), and the filtered water pipe 4 and the backwash are passed through the filtered water pipe 4, the first backwash pipe 26 and the first chemical supply pipe 28.
  • the mixed water in which the first chemical is mixed with the washing water 17 in the pipe 26 is suction-transferred to the first chemical storage tank 22.
  • the mixed water can be applied to the filtration membrane while maintaining the concentration of the mixed water containing the second chemical solution. That is, consider the case where only the washing water 17 is used as the method for removing the chemical solution.
  • the washing water 17 is used as a method for removing the chemical solution, if the water quality of the washing water 17 is poor (suspended solids or dissolved organic substances are contained in the washing water 17), the suspended solids or dissolved substances in the washing water 17 are contained. Suspended solids may react with the second drug solution (supplied after the elimination of the mixed water mixed with the first drug).
  • the mixed water containing the first chemical discharged from the membrane module 3 after the chemical solution is removed can be discharged into the water tank 2 to be treated and used as the water 1 to be treated used for the filtration treatment.
  • the mixed water containing the first chemical discharged from the membrane module 3 after the backflow cleaning may be separately collected and treated as a treated liquid.
  • the second backwash valve 36 is opened to start the second chemical supply pump 37, and the washing water pipe 24 from the washing water tank 18
  • the wash water 17 is supplied to the second backwash pipe 27 via the 24B and the switching valve 21.
  • the second drug supply valve 34 is opened to start the second drug supply pump 37, and the second drug storage tank 23 is connected to the second backwash pipe 27 via the second drug supply pipe 29. Supply the drug.
  • the washing water 17 and the second chemical are mixed in the second backwash pipe 27 to become mixed water.
  • the second backwash pipe 27 may be provided with a device (for example, a static mixer) that uniformly mixes the wash water 17 and the second chemical.
  • the mixed water containing the second chemical is supplied to the membrane module 3 via the filtered water pipe 4, and the filtered membrane in the membrane module 3 is backwashed.
  • a tank for accommodating the washing water 17 is provided in the second backwash pipe 27, the second chemical is supplied into the tank, the washing water 17 and the second chemical are uniformly mixed, and the mixed water is mixed.
  • the filtration membrane in the membrane module 3 may be backwashed by supplying the membrane module 3 with a pump.
  • the cleaning process can be performed by the above method.
  • the second backwash valve 36, the first backwash valve 32, the washing water supply valve 25 and the filtration valve 15 are opened, the filtration pump 16 is started, and the subject is covered.
  • the filtration treatment of the water to be treated 1 can be continuously and efficiently performed.
  • the filtration membrane cleaning device having the above configuration, in the method for removing the chemical solution when cleaning the filtration membrane using a plurality of chemical solutions, a plurality of chemical solutions remaining in the pipe are efficiently removed. It can be applied to the filtration membrane while maintaining the concentration of the chemical solution. In addition, since a method other than washing with washing water can be selected for removing the chemical solution, the washing water can be saved. It is also possible to eliminate the chemical solution in the pipe by alternately circulating the washing water and the gas filtered by the filtration membrane. Such a method is a cleaning method called "pulse cleaning", and when liquid and gas are alternately circulated, the cleaning ability for the filter membrane or the pipe is higher than when only liquid or gas is circulated. improves.
  • the filter membrane is washed with the mixed water in which the first chemical is mixed with the washing water 17, and then remains in the pipe.
  • the mixed water in which the first chemical was mixed with the washed water 17 was removed, and the filter membrane was washed with the mixed water in which the second chemical was mixed with the washing water 17, and then the washing water 17 remaining in the pipe was used for the second. It is a method of removing the mixed water in which the two chemicals are mixed.
  • wash water is used to remove the chemical solution remaining in the pipe, and if the washing water cannot be supplied, gas is used to remove the chemical solution remaining in the pipe, and the gas supply device. If it cannot be used, suction is used to remove the chemical solution remaining in the pipe.
  • the mixed water used in the method for cleaning the filtration membrane according to the present embodiment is not particularly limited as long as it is plural, but if the number of mixed waters is too large, the types of chemicals used for each mixed water must be increased. .. Therefore, the mixed water used in the method for cleaning the filtration membrane according to the present embodiment is preferably 2 or 3 types, more preferably 2 types, from the viewpoint of reducing the cleaning cost.
  • the method for cleaning the filtration membrane using two kinds of mixed water has been described as an example, but the method for cleaning the filtration membrane using three or more kinds of mixed water can also be adopted.
  • the cleaning water may be held in the membrane as it is, or the filtration membrane is immersed in the cleaning liquid and held. May be good.
  • the washing water used for removing the chemical solution according to the present embodiment needs to be changed in real time to a method for removing the chemical solution other than the washing water according to the amount of suspended solids in the washing water. Therefore, it is necessary to measure the turbidity of the washing water in real time using an online turbidity meter for the washing water used for removing the chemical solution according to the present embodiment.
  • the lower the turbidity in the washing water the more preferable, but it is preferably lower than 1 NTU, more preferably 0 NTU.
  • the gas used for removing the chemical solution according to the present embodiment it is preferable to use a gas having low toxicity, but if a gas requiring a cylinder is used, the cost required for removing the chemical solution cannot be suppressed. Therefore, it is preferable to use air generated by a blower as the gas used in the chemical solution removing method according to the present embodiment.
  • the filter membrane to be the target of the filter membrane cleaning method according to the present embodiment is a pollutant by filtering water to be treated such as water supply, sewerage, secondary treated sewage water, industrial wastewater, seawater, and urine. Is a filtration film in a state where is adhered to the surface or in the pores.
  • the material of the filtration membrane that can be used in the method for cleaning the filtration membrane of the present embodiment is not particularly limited as long as it is not deteriorated by a chemical agent.
  • materials for filtration membranes include polyolefins such as polyethylene, polypropylene and polybutene.
  • the material of the filter membrane include tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP (FLUORINATED ETHYLENE PROPYLENE)), and tetrafluoroethylene-ethylene.
  • polymers ETFE (ETHYLENE TETRAFLUOROETHYLENE)
  • PCTFE polychlorotrifluoroethylene
  • ECTFE chlorotrifluoroethylene-ethylene copolymer
  • fluororesin compounds such as polytetrafluoroethylene (PTFE (POLYTETRAFLUOROETHYLENE)
  • the material of the filtration membrane include celluloses such as cellulose acetate and ethyl cellulose, and ceramics.
  • the material of the filtration membrane is preferably a fluororesin compound having excellent resistance to a strong oxidizing agent such as ozone.
  • the material of the filtration membrane may be a single substance or a combination of two or more of the above substances.
  • the type of the filtration membrane is not particularly limited, and various filtration membranes such as a microfiltration (MF (MICROFILTRATION MEMBRANE)) membrane and an ultrafiltration (UF (ULTRAFILTRATION MEMBRANE)) membrane can be used.
  • the average pore size of the filtration membrane is not particularly limited, but is preferably 0.001 ⁇ m to 1 ⁇ m, and more preferably 0.01 ⁇ m to 0.1 ⁇ m. If the filtration membrane has an average pore size in this range, the filtration membrane cleaning method of the present embodiment can be used not only for pollutants adhering to the surface of the filtration membrane in contact with the water to be treated, but also for the filtration membrane in contact with the cleaning water.
  • the pollutant that is chemically attached to the surface or the pores of the filtration membrane can be efficiently removed.
  • the shape of the filtration membrane is not particularly limited, and can be a cylindrical shape or a flat membrane shape. Among them, the shape of the filtration membrane is preferably cylindrical.
  • the filtration membrane may be incorporated in the membrane module 3, and the membrane module 3 may be an immersion type, a casing type, or a monolith type. Further, the filtration method of the filtration membrane can be either a total filtration method or a cross-flow filtration method.
  • the water flow method of the filter membrane is not particularly limited, and is an external pressure filtration method in which the water to be treated flows outside the filter membrane and the wash water flows inside, and the water to be treated flows inside the filter membrane and the wash water flows outside. It may be any of the internal pressure filtration methods in which water is flowed.
  • the mixed water in which the first chemical is mixed with the washing water 17 and the mixed water in which the second chemical is mixed with the washing water 17 are not particularly limited as long as they are substances capable of decomposing organic substances or inorganic substances. Examples of chemical solutions capable of decomposing organic substances include sodium hypochlorite, hydrogen peroxide, sodium hydroxide, ozone water and the like. These can be used alone or in combination of two or more.
  • mixed water in which sodium hypochlorite or hydrogen peroxide is dissolved in washing water 17 can be used.
  • mixed water in which ozone is dissolved in the washing water 17 can be used.
  • an inorganic acid such as hydrochloric acid, sulfuric acid or nitric acid, or an organic acid such as oxalic acid or citric acid can be used. These can also be used alone or in combination of two or more. Further, two or more kinds of substances capable of decomposing organic substances and substances capable of decomposing inorganic substances can be used in combination. When two or more kinds of substances capable of decomposing organic substances and substances capable of decomposing inorganic substances are used in combination, which one is used as the mixed water in which the first drug is mixed or the mixed water in which the second drug is mixed is particularly limited.
  • a substance capable of decomposing an organic substance is used as a mixed water mixed with a first agent
  • a substance capable of decomposing an inorganic substance is used as a mixed water mixed with a second agent
  • a substance capable of decomposing an inorganic substance is used as a mixed water.
  • a substance capable of decomposing an organic substance may be used as the mixed water in which the second drug is mixed.
  • the concentration of the chemical solution in the washing water is not particularly limited, but when a substance capable of decomposing organic substances is used, sodium hypochlorite (effective chlorine concentration) is 1.0 g / L or more and 5.0 g / L or less, and sodium hydroxide is used. It is preferably 1.0 g / L or more and 4.0 g / L or less. For ozone water, it is preferably 5 mg / L or more and 100 mg / L or less, and more preferably 20 mg / L or more and 30 mg / L or less.
  • 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. It is preferably L or more and 10 g / L or less.
  • the cleaning time of the filtration membrane using the mixed water containing the chemical solution is not particularly limited, and may be appropriately set according to the amount of pollutants adhering to the filtration membrane. Generally, 90 minutes or less is preferable when sodium hypochlorite is used, and 5 to 7 minutes is preferable when oxalic acid or citric acid is used. It is preferable that the washing time is short, and when the washing time is long, the total washing time is long and the time for interrupting the filtration treatment by the filtration membrane of the water to be treated is also long, so that the amount of water to be filtered through the filtration membrane is reduced. That is, normally, in the filtration treatment using a filtration membrane for sewage and wastewater treatment, the water to be treated is filtered all day long.
  • the chemical solution cleaning of the filtration membrane is performed by stopping the filtration treatment of the water to be treated, the longer the cleaning time, the shorter the time for filtering the water to be treated. That is, since the time for filtering the water to be treated is shortened, the amount of water that can be filtered (the amount of washing water) is also reduced.
  • the membrane surface permeation flux (water permeation amount per membrane area) of the mixed water containing the chemical solution is not particularly limited. In general, it is sufficient to secure a flux that can be filled up to the end of the filtration membrane, and particularly when ozone water is used, it is sufficient to secure a flux that can maintain the concentration during transportation. Specifically, when sodium hypochlorite is used, it is 6 LMH (L / m 2 / h) or less, when ozone water is used, it is 50 LMH (L / m 2 / h) or less, and more preferably 30 LMH (L / h). m 2 / h) or less.
  • the permeation flux is too high, the cost of the drug increases as the required amount of mixed water increases. It also increases the capacity of the drug storage tank. If the permeation flux on the membrane surface is too low, the mixed water will not be filled to the end of the filtration membrane, and the pollutants adhering to the filtration membrane cannot be decomposed. When ozone water is used, the concentration decreases during transportation.
  • washing water and gas are generally used, and further, a suction method is used.
  • gas is preferably used, and washing water is more preferable.
  • the turbidity of the washing water In the state where the filtration membrane is not broken, that is, the suspended solids or dissolved organic substances in the water to be treated do not flow out into the washing water, the turbidity of the washing water generally shows 0 NTU.
  • the turbidity of the washing water generally shows 1 NTU or more.
  • the washing water from which the suspended solids or dissolved organic substances in the water to be treated have flowed out is used as a method for removing the chemical solution remaining in the pipe
  • the chemical solution reacts with the suspended solids or dissolved organic substances in the washing water, and the concentration of the chemical solution is concentrated. Cannot be maintained. That is, unlike the stage where the washing water 17 and the chemicals are mixed in the backwash pipe to generate the mixed water, it is necessary to keep the state as clean as possible at the stage where the chemical solution remaining in the pipe is removed. Therefore, in the selection of the chemical solution exclusion method, the washing water is preferentially selected, but when the turbidity of the washing water is 1 NTU or more, a gas is selected. If it is difficult to supply gas, select a suction method.
  • the timing of removing the chemical solution is before the supply of the mixed water mixed with the first drug, between the supply of the mixed water mixed with the first drug and the mixed water mixed with the second drug, and further. It is preferable after the supply of the mixed water mixed with the second agent, but more preferably between the supply of the mixed water mixed with the first agent and the supply of the mixed water mixed with the second agent. ..
  • the direction of chemical solution exclusion is the same flow direction as the mixed water mixed with the first drug and the mixed water mixed with the second drug, the mixed water mixed with the first drug and the mixed water mixed with the second drug.
  • the flow direction may be opposite to that of the above, but it is preferable that the flow direction is the same as that of the mixed water in which the first agent is mixed and the mixed water in which the second agent is mixed. That is, there are two directions for removing the chemical solution, one is from the secondary side to the primary side of the filtration membrane (the same direction as the flow of the chemical solution), and the other is from the primary side to the secondary side of the filtration membrane.
  • the direction (the same direction as the direction in which the water to be treated 1 is filtered). In removing the chemical solution, either direction may be used, but the same direction as the chemical solution (direction from the secondary side to the primary side of the filtration membrane) is preferable because the chemical solution in the pipe and the inside of the filtration membrane can be completely eliminated.
  • the method for treating the chemical solution excluded by the chemical solution exclusion is not particularly limited.
  • the flow direction is the same as that of the mixed water mixed with the first drug and the mixed water mixed with the second drug, it is preferable to eliminate the water in the filtration membrane or the reaction tank (water tank 2 to be treated), but it is excluded in the filtration membrane. It is more preferable to do so.
  • the flow direction opposite to that of the mixed water in which the first drug is mixed and the mixed water in which the second drug is mixed it is preferable to remove the drug into the drug storage tank or the treated water tank (washing water tank 18). It is more preferable to remove it into the storage tank.
  • the time for removing the chemical solution may be any time as long as it can secure a flow rate equal to or larger than the capacity of the pipe at the place where the mixed water mixed with the first drug and the mixed water mixed with the second drug pass. .. If the removal time is short, the chemical solution remaining in the pipe cannot be completely removed, so that the concentration of the chemical is lowered when the mixed water containing the chemical is supplied. If the exclusion time is long, the total washing time is long, so that the time for interrupting the filtration treatment of the water to be treated by the filtration membrane is also long, and the amount of water treated by the filtration membrane is reduced.
  • the flow velocity for removing the chemical solution may be appropriately set according to the amount of the chemical solution remaining in the pipe. It is preferable that the exclusion flow velocity is high, and if the exclusion flow velocity is slow, the chemical solution adhering to the pipe cannot be completely removed due to the decrease in shear stress caused by the exclusion flow rate. Decreases.
  • the chemical solution exclusion control method is controlled by measuring the integrated flow rate of the fluid used for chemical solution exclusion using an integrated flow meter 13 located between the filtration membrane and the second backwash valve 36. The value of the integrated flow meter 13 between the filtration membrane and the second backwash valve 36 is the capacity of the pipe where the mixed water mixed with the first chemical and the mixed water mixed with the second chemical pass.
  • the chemical solution exclusion step When the above is reached, it is preferable to end the chemical solution exclusion step. If the viscosity of the chemical solution to be excluded is 2 cP (mPa ⁇ s), it is twice the capacity of the pipe, and if it is 3 cP (mPa ⁇ s), it is 3 times or more the capacity of the pipe, the chemical solution removal step is terminated. Is more preferable. Further, the chemical solution exclusion method, the exclusion time, and the exclusion flow rate may be different between the mixed water in which the first drug is mixed and the mixed water in which the second drug is mixed.
  • the filtration membrane when the filtration membrane is washed with a plurality of chemicals, the filtration membrane is washed with mixed water containing the first chemical in order to avoid mixing of different kinds of chemicals in the pipe.
  • a chemical solution removing step is introduced between the cleaning of the filtration membrane with the mixed water containing the second chemical, and the chemical solution remaining in the pipe is removed.
  • the washing water 17 When the turbidity of the washing water 17 that has passed through the filtration membrane is low, the washing water 17 is used to remove the chemical solution remaining in the pipe, and when the turbidity of the washing water 17 is high, gas is used to remain in the pipe. When the gas cannot be supplied, the chemical solution remaining in the pipe is eliminated by using suction.
  • the filtration membrane is washed with a plurality of chemical solutions, the chemicals remaining in the piping are efficiently removed, the chemical solutions are prevented from reacting with each other, and the filtration is performed while maintaining the concentration of the multiple chemical solutions. Can be applied to the membrane.
  • the washing water can be saved by selecting a method other than washing with washing water that has passed through the filtration membrane for removing the chemical solution.
  • FIG. 2 is a conceptual diagram showing a water treatment system including the filtration membrane cleaning device according to the second embodiment. Since the basic configuration of the water treatment system including the filter membrane cleaning device according to the present embodiment is the same as that of the water treatment system including the filter membrane cleaning device according to the first embodiment, only the differences are obtained. explain. Further, the same reference numerals are given to the same configurations as those of the water treatment system including the filtration membrane cleaning device according to the first embodiment.
  • the water treatment system including the filtration membrane cleaning device according to the present embodiment has a structure suitable for using ozone as the mixed water mixed with the second chemical. That is, in the water treatment system including the filtration membrane cleaning device according to the present embodiment, the ozone water generation tower 45 is connected to the second backwash pipe 27 branched by the second backwash valve 36. Therefore, it is different from the water treatment system provided with the filtration membrane cleaning device according to the first embodiment.
  • An air diffuser 44 is arranged at the bottom of the ozone water generation tower 45, and an ozone generator 42 is connected to the air diffuser 44 via an ozone supply pipe 43.
  • the ozone raw material supplied to the ozone generator 42 is not particularly limited, and for example, liquid oxygen or oxygen generated by PSA (PRESSURE SWING ADSORPTION) or PVSA (PRESSURE VACUUM SWING ADSORPTION) can be used.
  • a water treatment system having such a structure, when backflow cleaning is performed using mixed water in which ozone (second chemical) is mixed with the cleaning water 17, the switching valve 20, the switching valve 21, and the second chemical are supplied.
  • the valve 34 is opened, the backwash pump 19 is started, and the wash water 17 is supplied from the wash water tank 18 to the ozone water generation tower 45 via the wash water pipes 24 and 24B and the second chemical supply valve 34.
  • ozone water as a mixed water in which ozone is mixed with the washing water 17 in the ozone water generation tower 45. To generate.
  • the ozone water generated in the ozone water generation tower 45 is supplied to the membrane module 3 via the second backwash pipe 27 and the filtered water pipe 4, and the filtered membrane in the membrane module 3 is backwashed. Further, in the water treatment system according to the present embodiment, the ozone exhaust pipe 46, the ozone exhaust treatment equipment 47, and the treated ozone pipe 48 are provided.
  • FIG. 2 illustrates the case where the air diffuser 44 is used as the ozone gas supply device
  • the device is not particularly limited as long as it can generate ozone water in which the ozone gas and the cleaning water 17 are in contact with each other.
  • an ozone gas supply device such as an ejector type, a mechanical stirring type, or a downward injection type can be used.
  • all pumps, valves, and switching valves are connected to a control device, and the operation of all pumps, valves, and switching valves is controlled by this control device.
  • ozone used as the mixed water mixed as the second chemical
  • either ozone or a chemical other than ozone is mixed as the first chemical.
  • ozone is used as mixed water or mixed water mixed as a second drug
  • a drug other than ozone is mixed as a second drug. It may be used as water.
  • FIG. 3 is a conceptual diagram showing a water treatment system including the filtration membrane cleaning device according to the third embodiment. Since the basic configuration of the water treatment system including the filter membrane cleaning device according to the present embodiment is the same as that of the water treatment system including the filter membrane cleaning device according to the first embodiment, only the differences are obtained. explain. Further, the same reference numerals are given to the same configurations as those of the water treatment system including the filtration membrane cleaning device according to the first embodiment.
  • the water treatment system including the filtration membrane cleaning device according to the present embodiment cleans the filtration membrane according to the first embodiment in that a water supply pipe 49 is provided instead of the backwash pump 19. It is different from the water treatment system equipped with the device.
  • the water supply pipe 49 is connected to the first backwash pipe 26 and the second backwash pipe 27 via the wash water pipe 24B branched by the switching valve 20.
  • the water supplied from the water supply pipe 49 according to the present embodiment is not particularly limited as long as the turbidity is lower than 1 NTU. Examples include tap water, groundwater, reservoir water, surface water, underground water, lake water, and seawater.
  • the switching valve 20, the washing water supply valve 25, the first backwash valve 32 and the second backwash valve 36 are opened to release water.
  • the switching valve 20, the switching valve 21, the first chemical supply valve 30, the first air supply valve 31, the first backwash valve 32, and the second backwash valve 36 are opened to supply water.
  • the switching valve 20, the switching valve 21, the second chemical supply valve 34, the second air supply valve 35, and the second backwash valve 36 are opened to supply water.
  • FIG. 4 is a conceptual diagram showing a water treatment system including the filtration membrane cleaning device according to the fourth embodiment. Since the basic configuration of the water treatment system including the filter membrane cleaning device according to the present embodiment is the same as that of the water treatment system including the filter membrane cleaning device according to the first embodiment, only the differences are obtained. explain. Further, the same reference numerals are given to the same configurations as those of the water treatment system including the filtration membrane cleaning device according to the first embodiment.
  • the water treatment system including the filtration membrane cleaning device according to the present embodiment is provided with a gas cylinder 50 as a gas supply device instead of the cleaning blower 38, and the filtration according to the first embodiment is provided. It differs from a water treatment system equipped with a membrane cleaning device.
  • the gas cylinder 50 is connected to the first backwash pipe 26 branched by the first air supply pipe 39 and the first air supply valve 31. Further, the gas cylinder 50 is connected to the second backwash pipe 27 branched by the second air supply pipe 40 and the second air supply valve 35.
  • the gas supplied from the gas cylinder 50 according to the present embodiment is not particularly limited as long as it is not toxic to the human body, and a substance known in the art can be used. Examples include oxygen, nitrogen, carbon dioxide and carbon dioxide.
  • the first air supply valve 31, the first backwash valve 32 and the second backwash valve 36 are opened to supply gas. ..
  • the second air supply valve 35 and the second backwash valve 36 are opened to supply gas.
  • the chemical elimination method can be selected according to the pressure of the gas cylinder 50.
  • a chemical solution elimination method can be selected according to the pressure of the air pump. For example, when the residual pressure of the gas cylinder 50 decreases, the pressure of the pressure gauge 14 decreases. In addition, if the air pump also fails or a pipe leaks, the pressure of the pressure gauge 14 also drops. Even if such a problem occurs, another chemical solution exclusion method can be selected, so that the chemical solution elimination is not hindered.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Microbiology (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

The present invention comprises: a treated-water tank (2) that accommodates water for treatment (1); a membrane module (3) having a filtration membrane that filters the water for treatment (1) and is positioned in the treated-water tank (2); a plurality of chemical-solution-supply units that, in a respective manner, supply a plurality of chemical solutions for cleaning the filtration membrane; a cleaning water tank (18) that accommodates cleaning water (17), which is filtered water that has been filtered by the membrane module (3), the cleaning water (17) being used in order to remove the chemical solutions remaining within piping by which the chemical solution supply units and the treated-water tank (2) are connected; an air supply device that supplies air used in order to remove the chemical solutions remaining within the piping; and an integrating flowmeter (13) that measures the integrated flow rate of the cleaning liquid (17) or the air used in removing the chemical solutions, the integrating flowmeter (13) being positioned in the piping.

Description

水処理システムWater treatment system
 本願は、水処理システムに関するものである。 This application relates to a water treatment system.
被処理水の懸濁物質を分離する方法として、濾過膜を利用した膜処理が用いられている。例えば、下水及び工場廃水の処理において、活性汚泥法により被処理水を処理した後、濾過膜を用いて懸濁物質を分離除去している。濾過膜としては、一般的に円筒状又はシート状の精密濾過膜及び限外濾過膜が用いられている。また濾過方式として、円筒状又はシート状の濾過膜の外側に被処理水を流し、内側に濾過水を流す外圧濾過方式と、円筒状の濾過膜の内側に被処理水を流し、外側に濾過水を流す内圧濾過方式とがある。このような濾過膜を用いた膜処理では、濾過膜の継続的な使用に伴い濾過性能が低下する。 Membrane treatment using a filtration membrane is used as a method for separating suspended solids in water to be treated. For example, in the treatment of sewage and factory wastewater, after treating the water to be treated by the activated sludge method, suspended solids are separated and removed using a filtration membrane. As the filtration membrane, a cylindrical or sheet-shaped microfiltration membrane and an ultrafiltration membrane are generally used. In addition, as a filtration method, there are an external pressure filtration method in which the water to be treated flows outside the cylindrical or sheet-shaped filtration membrane and the filtered water flows inward, and an external pressure filtration method in which the water to be treated flows inside the cylindrical filtration membrane and filters outside. There is an internal pressure filtration method in which water flows. In the membrane treatment using such a filtration membrane, the filtration performance deteriorates with the continuous use of the filtration membrane.
具体的には、濾過膜の継続的な使用に伴い、被処理水と接する濾過膜の表面(外圧濾過方式では外面、内圧濾過方式では内面)、濾過水と接する濾過膜の表面(外圧濾過方式では内面、内圧濾過方式では外面)、又は濾過膜の孔中に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。特に濾過膜に目詰りが生じると、濾過時に必要な圧力が増加するため、膜濾過流束(単位時間、単位膜面積当たりの膜濾過水量)も低下してしまう。そのため、濾過膜の性能を維持するためには、濾過膜を定期的に洗浄する必要がある。 Specifically, with the continuous use of the filter membrane, the surface of the filter membrane in contact with the water to be treated (outer surface in the external pressure filtration method, the inner surface in the internal pressure filtration method), and the surface of the filter membrane in contact with the filtered water (external pressure filtration method). Then, pollutants adhere to the inner surface, the outer surface in the internal pressure filtration method), or the pores of the filtration membrane, causing clogging, and the filtration performance gradually deteriorates. In particular, when the filtration membrane is clogged, the pressure required for filtration increases, so that the membrane filtration flux (unit time, amount of membrane-filtered water per unit membrane area) also decreases. Therefore, in order to maintain the performance of the filtration membrane, it is necessary to clean the filtration membrane regularly.
そこで濾過性能を維持する方法として、濾過膜の一次側とは逆方向の二次側から次亜塩素酸ナトリウム(「次亜塩素酸ソーダ」とも呼ばれる)又はオゾン等の酸化剤を含有する洗浄水を用いて濾過膜の逆流洗浄を行うことにより、膜濾過水と接する濾過膜の表面又は濾過膜の孔中に分子間力で化学的に付着した汚濁物質を酸化分解して洗浄する方法がある。 Therefore, as a method for maintaining the filtration performance, washing water containing an oxidizing agent such as sodium hypochlorite (also called "sodium hypochlorite") or ozone is used from the secondary side in the direction opposite to the primary side of the filtration film. There is a method of oxidatively decomposing and cleaning pollutants chemically adhered by intermolecular force to the surface of the filter membrane in contact with the membrane-filtered water or the pores of the filter membrane by performing backflow cleaning of the filter membrane using ..
また複数の薬液、例えば次亜塩素酸ナトリウム等のアルカリ性物質、又は塩酸、硫酸、クエン酸等の酸性物質をそれぞれ別の薬液タンクに貯留し、切り替え弁により複数の洗浄水を順次通水する濾過膜の洗浄方法がある(特許文献1参照)。 Further, a plurality of chemical solutions, for example, an alkaline substance such as sodium hypochlorite, or an acidic substance such as hydrochloric acid, sulfuric acid, and citric acid are stored in separate chemical solution tanks, and a switching valve is used to sequentially pass a plurality of wash waters through filtration. There is a method for cleaning the membrane (see Patent Document 1).
更に酸化剤による洗浄効果をより高めるため、次亜塩素酸ナトリウムを含有する洗浄水を用いて濾過膜の逆流洗浄を行った後、オゾンを含有する洗浄水を用いて濾過膜を逆流洗浄する方法もある(特許文献2参照)。 Further, in order to further enhance the cleaning effect of the oxidizing agent, a method of performing backflow cleaning of the filter membrane with cleaning water containing sodium hypochlorite and then backflow cleaning of the filter membrane with cleaning water containing ozone. There is also (see Patent Document 2).
特開2005-193132号公報Japanese Unexamined Patent Publication No. 2005-193132 特許第5933854号Patent No. 5933854
濾過膜を利用した膜処理では、濾過膜の継続的な使用に伴い濾過膜が破断し、被処理水中の懸濁物質及び溶存態有機物が濾過水に流出することがある。被処理水中の懸濁物質及び溶存態有機物が流出した洗浄水を用いて配管内に残存した薬液の排除を行うと、薬液と洗浄水中の懸濁物質、溶存態有機物が反応し薬液の濃度を維持することができないという問題点があった。 In the membrane treatment using the filter membrane, the filter membrane may break with the continuous use of the filter membrane, and suspended solids and dissolved organic substances in the water to be treated may flow out into the filtered water. When the chemical solution remaining in the pipe is removed using the wash water from which the suspended solids and dissolved organic substances in the water to be treated have flowed out, the chemical solution reacts with the suspended solids and dissolved organic substances in the washing water to increase the concentration of the chemical solution. There was a problem that it could not be maintained.
本願は、上記のような問題を解決するための技術を開示するものであり、複数の薬液の濃度を維持しながら薬液を濾過膜に供することができる水処理システムを提供することを目的とする。 The present application discloses a technique for solving the above-mentioned problems, and an object of the present application is to provide a water treatment system capable of supplying a chemical solution to a filtration membrane while maintaining the concentration of a plurality of chemical solutions. ..
本願に開示される水処理システムは、被処理水を収容する被処理水槽と、前記被処理水槽に設置されるとともに前記被処理水を濾過処理する濾過膜を有する膜モジュールと、前記濾過膜を洗浄するための複数の薬液をそれぞれ供給する複数の薬液供給部と、前記膜モジュールで濾過処理された濾過水であって、前記薬液供給部と前記被処理水槽を接続する配管内に残存した前記薬液を排除するために用いられる洗浄水を収容する洗浄水槽と、前記配管内に残存した前記薬液を排除するために用いられる気体を供給する気体供給装置と、前記配管に設置されるとともに、前記薬液の排除に用いられる前記洗浄水または前記気体の積算流量を測定する積算流量計とを備え、
前記積算流量計の値が、前記配管における配管内容量以上になった場合に前記薬液の排除を終了する水処理システム。
The water treatment system disclosed in the present application comprises a water tank to be treated, a membrane module installed in the water tank to be treated and having a filtration film for filtering the water to be treated, and the filtration membrane. A plurality of chemical solution supply units for supplying a plurality of chemical solutions for cleaning, and filtered water filtered by the membrane module, which remains in a pipe connecting the chemical solution supply unit and the water tank to be treated. A washing water tank containing washing water used for removing the chemical solution, a gas supply device for supplying the gas used for removing the chemical solution remaining in the pipe, and a gas supply device installed in the pipe and described above. It is equipped with an integrated flow meter that measures the integrated flow rate of the washing water or the gas used for removing the chemical solution.
A water treatment system that ends the removal of the chemical solution when the value of the integrated flow meter exceeds the capacity of the pipe in the pipe.
本願に開示される水処理システムによれば、複数の薬液の濃度を維持しながら薬液を濾過膜に供することができる。 According to the water treatment system disclosed in the present application, the chemical solution can be applied to the filtration membrane while maintaining the concentration of the plurality of chemical solutions.
実施の形態1に係る濾過膜の洗浄装置を備える水処理システムを示す概念図である。It is a conceptual diagram which shows the water treatment system which includes the filtration membrane cleaning apparatus which concerns on Embodiment 1. FIG. 実施の形態2に係る濾過膜の洗浄装置を備える水処理システムを示す概念図である。It is a conceptual diagram which shows the water treatment system which includes the filtration membrane cleaning apparatus which concerns on Embodiment 2. 実施の形態3に係る濾過膜の洗浄装置を備える水処理システムを示す概念図である。It is a conceptual diagram which shows the water treatment system which includes the filtration membrane cleaning apparatus which concerns on Embodiment 3. FIG. 実施の形態4に係る濾過膜の洗浄装置を備える水処理システムを示す概念図である。It is a conceptual diagram which shows the water treatment system which includes the filtration membrane cleaning apparatus which concerns on Embodiment 4. FIG.
実施の形態1.
本実施の形態は、上水道、下水道、工業用水、各種廃水等の被処理水から濾過膜により懸濁物質を分離する際に使用される濾過膜の洗浄装置を有する水処理システムに関するものである。
複数の薬液を用いて濾過膜を洗浄する方法では、異なる種類の薬液が配管内で混合し反応すると、洗浄に供する薬液の濃度の低下及び有毒なガスの発生が想定される。従ってこれらの薬液が極力混合しないよう操作をする必要がある。特にオゾンと次亜塩素酸ナトリウムが混合すると、オゾン濃度が直ちに低下することが分かっており、複数の薬液を用いて濾過膜を洗浄する方法では、配管内に残存した薬液の排除機構を設けることが望ましい。そのため複数の薬液を用いて濾過膜を洗浄する方法では、薬液を濾過膜へ供給後、洗浄水(濾過水)を配管内へ通水し配管内に残存した薬液を排除する。これにより異なる種類の薬液が配管内で混合し濃度が低下することを防止する。本実施の形態は異なる種類の薬液が配管内で混合し濃度が低下することを防止するための水処理システムを提供するものである。
Embodiment 1.
The present embodiment relates to a water treatment system having a filter membrane cleaning device used for separating suspended solids from treated water such as water supply, sewerage, industrial water, and various wastewaters by a filter membrane.
In the method of cleaning the filtration membrane using a plurality of chemical solutions, when different types of chemical solutions are mixed and reacted in the pipe, it is expected that the concentration of the chemical solution used for cleaning will decrease and toxic gas will be generated. Therefore, it is necessary to operate so that these chemicals are not mixed as much as possible. In particular, it is known that when ozone and sodium hypochlorite are mixed, the ozone concentration decreases immediately, and in the method of cleaning the filtration membrane using multiple chemical solutions, a mechanism for removing the chemical solution remaining in the piping should be provided. Is desirable. Therefore, in the method of cleaning the filter membrane using a plurality of chemical solutions, after the chemical solution is supplied to the filter membrane, the washing water (filtered water) is passed through the pipe to eliminate the chemical solution remaining in the pipe. This prevents different types of chemicals from mixing in the pipe and reducing the concentration. The present embodiment provides a water treatment system for preventing different types of chemicals from mixing in a pipe and reducing the concentration.
以下、本実施の形態に係る薬液排除装置の好適な実施の形態について図面を用いて説明する。
図1は、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムを示す概念図である。図において、水処理システムは濾過装置を備えている。濾過装置は被処理水1を収容する被処理水槽2と、被処理水1を濾過処理する濾過膜を有する膜モジュール3と、膜モジュール3で濾過処理された濾過水(後述する洗浄水17として使用される)を排出する濾過水配管4とを有する。被処理水槽2には、被処理水1を供給する被処理水供給配管5が設けられており、濾過水配管4には、膜モジュール3側から積算流量計13、第2の逆洗バルブ36、第1の逆洗バルブ32、洗浄水供給バルブ25、圧力計14、濾過バルブ15及び濾過ポンプ16が順に設けられている。また、被処理水槽2には汚泥引抜配管6及び汚泥循環配管7が接続されており、被処理水槽2の底部に散気装置8が配置されている。また、汚泥引抜配管6には汚泥を引抜くための汚泥引抜ポンプ9が設けられるとともに、汚泥循環配管7には汚泥を被処理水槽2内で循環させるための汚泥循環ポンプ10が設けられている。更に散気装置8には、空気供給配管11を介して膜面曝気ブロワ12が接続されている。
Hereinafter, a preferred embodiment of the chemical solution removing device according to the present embodiment will be described with reference to the drawings.
FIG. 1 is a conceptual diagram showing a water treatment system including the filtration membrane cleaning device according to the first embodiment. In the figure, the water treatment system is equipped with a filtration device. The filtration device includes a water tank 2 to be treated for accommodating the water to be treated 1, a membrane module 3 having a filtration film for filtering the water to be treated 1, and filtered water filtered by the membrane module 3 (as wash water 17 described later). It has a filtered water pipe 4 for discharging (used). The water tank 2 to be treated is provided with a water supply pipe 5 to be treated to supply the water 1 to be treated, and the filtered water pipe 4 is provided with an integrated flow meter 13 and a second backwash valve 36 from the membrane module 3 side. , The first backwash valve 32, the wash water supply valve 25, the pressure gauge 14, the filter valve 15, and the filter pump 16 are provided in this order. Further, a sludge extraction pipe 6 and a sludge circulation pipe 7 are connected to the water tank 2 to be treated, and an air diffuser 8 is arranged at the bottom of the water tank 2 to be treated. Further, the sludge extraction pipe 6 is provided with a sludge extraction pump 9 for extracting sludge, and the sludge circulation pipe 7 is provided with a sludge circulation pump 10 for circulating sludge in the water tank 2 to be treated. .. Further, a membrane surface aeration blower 12 is connected to the air diffuser 8 via an air supply pipe 11.
この濾過装置において被処理水1の濾過処理を行う場合、濾過バルブ15を開き、濾過ポンプ16を起動させることにより、被処理水1が膜モジュール3で濾過される。そして膜モジュール3で濾過された濾過水は、濾過水配管4を介して洗浄水槽18へ排出される。膜モジュール3において、被処理水1の継続的な濾過処理を行うと、膜モジュール3中の濾過膜が汚濁物質によって目詰まりするため、濾過膜の洗浄を行う必要がある。
そこでこの水処理システムは、濾過膜の洗浄装置を更に備えている。濾過膜の洗浄装置は、薬液として洗浄水17に第1の薬剤を混合した混合水を用いて濾過膜を洗浄する方法と、薬液として洗浄水17に第2の薬剤を混合した混合水を用いて濾過膜を洗浄する方法とを備えている。
When the water to be treated 1 is filtered in this filtration device, the water to be treated 1 is filtered by the membrane module 3 by opening the filtration valve 15 and activating the filtration pump 16. Then, the filtered water filtered by the membrane module 3 is discharged to the washing water tank 18 via the filtered water pipe 4. When the membrane module 3 is continuously filtered with the water to be treated 1, the filtration membrane in the membrane module 3 is clogged with pollutants, so that it is necessary to clean the filtration membrane.
Therefore, this water treatment system is further equipped with a filtration membrane cleaning device. The filter membrane cleaning device uses a method of cleaning the filter membrane using a mixed water in which the first agent is mixed with the cleaning water 17 as a chemical solution, and a mixed water in which the cleaning water 17 is mixed with the second agent as the chemical solution. It is provided with a method of cleaning the filter membrane.
具体的には図1に示すように、濾過膜の洗浄装置は、洗浄水17を収容する洗浄水槽18と、第1の薬剤を収容する第1の薬剤貯留槽22と、第2の薬剤を収容する第2の薬剤貯留槽23とを備えている。洗浄水槽18には、濁度計41と洗浄水配管24が設けられている。洗浄水配管24には、逆洗ポンプ19及び切換弁20が設けられている。また、洗浄水配管24は2つに分岐しており、一方の洗浄水配管24Aは洗浄水供給バルブ25において濾過水配管4に接続されている。他方の洗浄水配管24Bは、切換弁21において第1の逆洗配管26と第2の逆洗配管27に接続されている。 Specifically, as shown in FIG. 1, the filtration membrane cleaning device includes a cleaning water tank 18 for accommodating the cleaning water 17, a first drug storage tank 22 for accommodating the first drug, and a second drug. It is provided with a second drug storage tank 23 for accommodating. The washing water tank 18 is provided with a turbidity meter 41 and a washing water pipe 24. The wash water pipe 24 is provided with a backwash pump 19 and a switching valve 20. Further, the washing water pipe 24 is branched into two, and one washing water pipe 24A is connected to the filtered water pipe 4 by the washing water supply valve 25. The other wash water pipe 24B is connected to the first backwash pipe 26 and the second backwash pipe 27 at the switching valve 21.
第1の逆洗配管26は、第1の空気供給バルブ31において第1の空気供給配管39に接続されており、第2の逆洗配管27は、第2の空気供給バルブ35において第2の空気供給配管40に接続されている。また第1の空気供給配管39及び第2の空気供給配管40には、洗浄ブロワ38が設けられている。そして第1の空気供給配管39、第2の空気供給配管40及び洗浄ブロワ38により濾過膜を洗浄するための空気供給装置が構成されている。尚空気のみならず他の気体であっても良く、後に説明するように、気体供給装置により気体を供給することにより配管内に残存した薬液を排除することができる。 The first backwash pipe 26 is connected to the first air supply pipe 39 at the first air supply valve 31, and the second backwash pipe 27 is connected to the second air supply pipe 39 at the second air supply valve 35. It is connected to the air supply pipe 40. A cleaning blower 38 is provided in the first air supply pipe 39 and the second air supply pipe 40. An air supply device for cleaning the filtration membrane is configured by the first air supply pipe 39, the second air supply pipe 40, and the cleaning blower 38. It should be noted that not only air but also other gases may be used, and as will be described later, the chemical solution remaining in the pipe can be eliminated by supplying the gas by the gas supply device.
第1の薬剤貯留槽22には第1の薬剤供給配管28が設けられており、第1の薬剤供給配管28は第1の逆洗配管26に接続されている。第2の薬剤貯留槽23には、第2の薬剤供給配管29が設けられており、第2の薬剤供給配管29は第2の逆洗配管27に接続されている。第1の薬剤供給配管28には、第1の薬剤供給バルブ30及び第1の薬剤供給ポンプ33(後に説明するように吸引装置としても動作する)が設けられており、第2の薬剤供給配管29には、第2の薬剤供給バルブ34及び第2の薬剤供給ポンプ37(後に説明するように吸引装置としても動作する)が設けられている。そして第1の薬剤貯留槽22、第1の薬剤供給ポンプ33、第1の薬剤供給配管28、第1の逆洗配管26により薬剤供給部が構成されるとともに、第2の薬剤貯留槽23、第2の薬剤供給ポンプ37、第2の薬剤供給配管29、第2の逆洗配管27により薬剤供給部が構成される。
なお図示していないが、全てのポンプ、バルブ、並びに切換弁は、制御装置に接続されおり、この制御装置により、全てのポンプ、バルブ、並びに切換弁の動作が制御される。
The first chemical storage tank 22 is provided with a first chemical supply pipe 28, and the first chemical supply pipe 28 is connected to the first backwash pipe 26. The second chemical storage tank 23 is provided with a second chemical supply pipe 29, and the second chemical supply pipe 29 is connected to the second backwash pipe 27. The first drug supply pipe 28 is provided with a first drug supply valve 30 and a first drug supply pump 33 (which also operates as a suction device as described later), and is provided with a second drug supply pipe. The 29 is provided with a second drug supply valve 34 and a second drug supply pump 37 (which also operates as a suction device as will be described later). The drug supply unit is composed of the first drug storage tank 22, the first drug supply pump 33, the first drug supply pipe 28, and the first backwash pipe 26, and the second drug storage tank 23, The chemical supply unit is composed of the second chemical supply pump 37, the second chemical supply pipe 29, and the second backwash pipe 27.
Although not shown, all pumps, valves, and switching valves are connected to a control device, which controls the operation of all pumps, valves, and switching valves.
上記のような構成を有する濾過膜の洗浄装置を用いて濾過膜の洗浄処理を行う場合、まず濾過ポンプ16を停止して濾過バルブ15を閉じた後、濾過膜の洗浄処理を開始する。被処理水1の濾過処理から濾過膜の洗浄処理への切換えは、濾過処理の時間によって管理すればよい。
濾過処理の終了後、濾過膜の洗浄処理を開始する前に、膜モジュール3中の濾過膜を予備処理することができる。例えば、膜モジュール3中の濾過膜を一定の間空気に曝すことにより、被処理水1と接する濾過膜の表面に付着した汚濁物質を除去し易くできる。又切換弁20及び洗浄水供給バルブ25及び第1の逆洗バルブ32及び第2の逆洗バルブ36を開けて逆洗ポンプ19を起動し、洗浄水槽18から洗浄水配管24、24A及び濾過水配管4を介して洗浄水17を膜モジュール3に供給することにより、濾過膜を予備洗浄してもよい。
When the filtration membrane cleaning treatment is performed using the filtration membrane cleaning device having the above configuration, the filtration pump 16 is first stopped, the filtration valve 15 is closed, and then the filtration membrane cleaning treatment is started. The switching from the filtration treatment of the water to be treated 1 to the cleaning treatment of the filtration membrane may be controlled by the time of the filtration treatment.
After the filtration treatment is completed and before the cleaning treatment of the filtration membrane is started, the filtration membrane in the membrane module 3 can be pretreated. For example, by exposing the filtration membrane in the membrane module 3 to air for a certain period of time, it is possible to easily remove pollutants adhering to the surface of the filtration membrane in contact with the water to be treated 1. Further, the switching valve 20, the washing water supply valve 25, the first backwash valve 32, and the second backwash valve 36 are opened to start the backwash pump 19, and the washing water pipes 24, 24A and filtered water are started from the washing water tank 18. The filter membrane may be pre-cleaned by supplying the cleaning water 17 to the membrane module 3 via the pipe 4.
又切換弁20、切換弁21、第1の薬剤供給バルブ30、第1の空気供給バルブ31、第1の逆洗バルブ32及び第2の逆洗バルブ36を開けて逆洗ポンプ19を起動し、洗浄水槽18から洗浄水配管24、24B、第1の逆洗配管26及び濾過水配管4を介して洗浄水17を膜モジュール3に供給することにより、濾過膜を予備洗浄してもよい。
更には切換弁20、切換弁21、第2の薬剤供給バルブ34、第2の空気供給バルブ35及び第2の逆洗バルブ36を開けて逆洗ポンプ19を起動し、洗浄水槽18から洗浄水配管24、24B、第2の逆洗配管27及び濾過水配管4を介して洗浄水17を膜モジュール3に供給することにより、濾過膜を予備洗浄してもよい。
Further, the switching valve 20, the switching valve 21, the first chemical supply valve 30, the first air supply valve 31, the first backwash valve 32 and the second backwash valve 36 are opened to start the backwash pump 19. The filter membrane may be pre-cleaned by supplying the wash water 17 from the wash water tank 18 to the membrane module 3 via the wash water pipes 24 and 24B, the first backwash pipe 26, and the filtered water pipe 4.
Further, the switching valve 20, the switching valve 21, the second chemical supply valve 34, the second air supply valve 35, and the second backwash valve 36 are opened to start the backwash pump 19, and the washing water is washed from the washing water tank 18. The filter membrane may be pre-cleaned by supplying the wash water 17 to the membrane module 3 via the pipes 24 and 24B, the second backwash pipe 27, and the filtered water pipe 4.
また、第1の空気供給バルブ31、第1の逆洗バルブ32及び第2の逆洗バルブ36を開けて洗浄ブロワ38を起動し、第1の空気供給配管39、第1の逆洗配管26及び濾過水配管4を介して、空気を膜モジュール3に供給することにより、濾過膜を予備洗浄してもよい。
更に第2の空気供給バルブ35及び第2の逆洗バルブ36を開けて洗浄ブロワ38を起動し、第2の空気供給配管40、第2の逆洗配管27及び濾過水配管4を介して、空気を膜モジュール3に供給することにより、濾過膜を予備洗浄してもよい。
これら予備洗浄を行う場合も同様に、被処理水1と接する濾過膜の表面に付着した汚濁物質を除去し易くできる。
Further, the first air supply valve 31, the first backwash valve 32, and the second backwash valve 36 are opened to start the washing blower 38, and the first air supply pipe 39 and the first backwash pipe 26 are started. The filter membrane may be pre-cleaned by supplying air to the membrane module 3 via the filtered water pipe 4.
Further, the second air supply valve 35 and the second backwash valve 36 are opened to start the cleaning blower 38, and the cleaning blower 38 is started via the second air supply pipe 40, the second backwash pipe 27, and the filtered water pipe 4. The filter membrane may be pre-cleaned by supplying air to the membrane module 3.
Similarly, when performing these preliminary cleanings, it is possible to easily remove the pollutant substances adhering to the surface of the filtration membrane in contact with the water to be treated 1.
濾過膜の洗浄処理では、まず切換弁20を開けて逆洗ポンプ19を起動し、洗浄水槽18から洗浄水配管24、24B及び切換弁21を介して第1の逆洗配管26に洗浄水17を供給すると共に、第1の薬剤供給バルブ30を開けて第1の薬剤供給ポンプ33を起動し、第1の薬剤貯留槽22から第1の薬剤供給配管28を介して第1の逆洗配管26に第1の薬剤を供給する。これにより、第1の逆洗配管26内で洗浄水17と第1の薬剤とが混合され、混合水が生成される。なお図示していないが、第1の逆洗配管26には、洗浄水17と第1の薬剤とを均一に混合する装置(例えば、スタティックミキサ)を設けてもよい。 In the cleaning process of the filter membrane, first, the switching valve 20 is opened to start the backwash pump 19, and the washing water 17 is connected to the first backwashing pipe 26 from the washing water tank 18 via the washing water pipes 24 and 24B and the switching valve 21. The first drug supply valve 30 is opened to start the first drug supply pump 33, and the first backwash pipe is supplied from the first drug storage tank 22 via the first drug supply pipe 28. The first agent is supplied to 26. As a result, the washing water 17 and the first chemical are mixed in the first backwashing pipe 26, and the mixed water is generated. Although not shown, the first backwash pipe 26 may be provided with a device (for example, a static mixer) that uniformly mixes the wash water 17 and the first chemical.
そして、第1の薬剤を含有する混合水を濾過水配管4を介して膜モジュール3に供給し、膜モジュール3中の濾過膜を逆流洗浄する。或いは第1の逆洗配管26に洗浄水17を収容する槽を設け、その槽内に第1の薬剤を供給して洗浄水17と第1の薬剤とを均一に混合し、この混合水をポンプで膜モジュール3に供給して膜モジュール3中の濾過膜を逆流洗浄してもよい。逆流洗浄後に膜モジュール3から排出される第1の薬剤を含有する混合水は、被処理水槽2内に排出し、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膜モジュール3から排出される第1の薬剤を含有する混合水は、処理済液として別途回収して処理してもよい。なお、以下に説明する各逆洗処理後の混合水についても、上記と同様に処理することができる。 Then, the mixed water containing the first chemical is supplied to the membrane module 3 via the filtered water pipe 4, and the filtered membrane in the membrane module 3 is backwashed. Alternatively, a tank for accommodating the washing water 17 is provided in the first backwash pipe 26, the first chemical is supplied into the tank, the washing water 17 and the first chemical are uniformly mixed, and the mixed water is mixed. The filtration membrane in the membrane module 3 may be backwashed by supplying the membrane module 3 with a pump. The mixed water containing the first chemical discharged from the membrane module 3 after the backflow cleaning can be discharged into the water tank 2 to be treated and used as the water 1 to be treated used for the filtration treatment. Alternatively, the mixed water containing the first chemical discharged from the membrane module 3 after the backflow cleaning may be separately collected and treated as a treated liquid. The mixed water after each backwashing treatment described below can also be treated in the same manner as described above.
又薬液排除の制御方法においては、膜モジュール3と第2の逆洗バルブ36の間にある積算流量計13を用いて、薬液排除における積算流量を測定することにより制御する。膜モジュール3と第2の逆洗バルブ36の間にある積算流量計13の値が、薬液として洗浄水17に第1の薬剤を混合した混合水及び薬液として洗浄水17に第2の薬剤を混合した混合水が通水する箇所の配管内容量以上になった場合に薬液排除工程を終了することが好ましい。
ここで配管内容量とは、配管内を満たしている薬液量のことを指す。例えば、薬液が通る箇所の配管の直径が10cm、配管の長さが全長10mであれば、配管内容量は0.05m×0.05m×3.14×10m=0.0785mとなる。薬液排除を実施する時間は、この配管内容量以上の洗浄水17又は気体を流せば良いということになる。例えば、洗浄水1m/minを配管内容量0.0785mになるまで流す場合、0.0785m÷1m/min=0.0785minとなり、洗浄水17を0.0785min以上流せば、配管内に残存している薬液を置換(排除)できることになる。
そして排除される薬液の粘度が2cP(CENTI POISE)、(mPa・s)ならば配管内容量の2倍、3cP(mPa・s)ならば配管内容量の3倍以上になった場合に薬液排除工程を終了することがより好ましい。また薬液排除の方法、排除時間及び排除流速は、洗浄水17に第1の薬剤を混合した混合水と洗浄水17に第2の薬剤を混合した混合水との間で差異を設けてもよい。
Further, in the method of controlling the chemical solution exclusion, the integrated flow rate meter 13 located between the membrane module 3 and the second backwash valve 36 is used to measure the integrated flow rate in the chemical solution exclusion. The value of the integrated flow meter 13 between the membrane module 3 and the second backwash valve 36 indicates that the mixed water in which the first drug is mixed with the washing water 17 as the chemical solution and the second drug in the washing water 17 as the chemical solution. It is preferable to end the chemical solution elimination step when the mixed water exceeds the capacity of the pipe at the place where the mixed water passes.
Here, the capacity inside the pipe refers to the amount of chemical solution filling the inside of the pipe. For example, if the diameter of the pipe through which the chemical solution passes is 10 cm and the length of the pipe is 10 m in total length, the internal capacity of the pipe is 0.05 m × 0.05 m × 3.14 × 10 m = 0.0785 m 3 . As for the time for removing the chemical solution, it is sufficient to flow the washing water 17 or the gas having a capacity equal to or larger than the capacity of the pipe. For example, if the flow of cleaning water 1 m 3 / min until the pipe inner volume 0.0785m 3, 0.0785m 3 ÷ 1m 3 /min=0.0785min next, be allowed to flow washing water 17 or 0.0785Min, the pipe It is possible to replace (eliminate) the chemical solution remaining in.
If the viscosity of the chemical solution to be excluded is 2 cP (CENTI POISE), (mPa · s), it is twice the capacity of the pipe, and if it is 3 cP (mPa · s), the chemical solution is eliminated when it is 3 times or more the capacity of the pipe. It is more preferable to end the process. Further, the method of removing the chemical solution, the exclusion time, and the exclusion flow rate may be different between the mixed water in which the first agent is mixed with the washing water 17 and the mixed water in which the second agent is mixed in the washing water 17. ..
次に濁度計41により計測した洗浄水17の濁度が1NTU(NEPHELOMETRIC TURBIDITY UNIT)(1NTUを濁度設定値とする)より低い場合は、切換弁20及び洗浄水供給バルブ25及び第1の逆洗バルブ32及び第2の逆洗バルブ36を開けて逆洗ポンプ19を起動し、洗浄水槽18から洗浄水配管24、24A及び濾過水配管4を介して洗浄水17を膜モジュール3に供給することにより、膜モジュール3中の濾過膜を逆流洗浄する。
あるいは切換弁20、切換弁21、第1の薬剤供給バルブ30、第1の空気供給バルブ31、第1の逆洗バルブ32及び第2の逆洗バルブ36を開けて逆洗ポンプ19を起動し、洗浄水槽18から洗浄水配管24、24B及び第1の逆洗配管26及び濾過水配管4を介して洗浄水17を膜モジュール3に供給することにより、膜モジュール3中の濾過膜を逆流洗浄する。
あるいは切換弁20、切換弁21、第2の薬剤供給バルブ34、第2の空気供給バルブ35及び第2の逆洗バルブ36を開けて逆洗ポンプ19を起動し、洗浄水槽18から洗浄水配管24、24B及び第2の逆洗配管27及び濾過水配管4を介して洗浄水17を膜モジュール3に供給することにより、膜モジュール3中の濾過膜を逆流洗浄する。
Next, when the turbidity of the wash water 17 measured by the turbidity meter 41 is lower than 1 NTU (NEPHELOMETRIC TURBIDITY UNIT) (1 NTU is set as the turbidity set value), the switching valve 20, the wash water supply valve 25 and the first The backwash valve 32 and the second backwash valve 36 are opened to start the backwash pump 19, and the wash water 17 is supplied from the wash water tank 18 to the membrane module 3 via the wash water pipes 24 and 24A and the filtered water pipe 4. By doing so, the filter membrane in the membrane module 3 is backwashed.
Alternatively, the switching valve 20, the switching valve 21, the first chemical supply valve 30, the first air supply valve 31, the first backwash valve 32, and the second backwash valve 36 are opened to start the backwash pump 19. By supplying the washing water 17 from the washing water tank 18 to the membrane module 3 via the washing water pipes 24 and 24B, the first backwashing pipe 26, and the filtered water pipe 4, the filtered membrane in the membrane module 3 is backwashed. do.
Alternatively, the switching valve 20, the switching valve 21, the second chemical supply valve 34, the second air supply valve 35, and the second backwash valve 36 are opened to start the backwash pump 19, and the wash water pipe is connected from the wash water tank 18. By supplying the washing water 17 to the membrane module 3 via the 24, 24B, the second backwash pipe 27, and the filtered water pipe 4, the filtered membrane in the membrane module 3 is backwashed.
また濁度計41の計測により洗浄水17の濁度が1NTU以上となった場合は、第1の空気供給バルブ31、第1の逆洗バルブ32及び第2の逆洗バルブ36を開けて洗浄ブロワ38を起動し、第1の空気供給配管39、第1の逆洗配管26及び濾過水配管4を介して、空気(気体)を膜モジュール3に供給することにより、膜モジュール3中の濾過膜を逆流洗浄する。
あるいは第2の空気供給バルブ35及び第2の逆洗バルブ36を開けて洗浄ブロワ38を起動し、第2の空気供給配管40、第2の逆洗配管27及び濾過水配管4を介して、空気(気体)を膜モジュール3に供給することにより、膜モジュール3中の濾過膜を逆流洗浄する。
If the turbidity of the washing water 17 is 1 NTU or more as measured by the turbidity meter 41, the first air supply valve 31, the first backwash valve 32, and the second backwash valve 36 are opened for washing. Filtering in the membrane module 3 by activating the blower 38 and supplying air (gas) to the membrane module 3 via the first air supply pipe 39, the first backwash pipe 26, and the filtered water pipe 4. Backwash the membrane.
Alternatively, the second air supply valve 35 and the second backwash valve 36 are opened to start the cleaning blower 38, and the cleaning blower 38 is started via the second air supply pipe 40, the second backwash pipe 27, and the filtered water pipe 4. By supplying air (gas) to the membrane module 3, the filtration membrane in the membrane module 3 is backwashed.
また洗浄ブロワ38が使用できない場合は、洗浄水供給バルブ25を閉じた後、第1の逆洗バルブ32、第2の逆洗バルブ36、第1の空気供給バルブ31、第1の薬剤供給バルブ30を開けて第1の薬剤供給ポンプ33(吸引装置)を起動し、濾過水配管4及び第1の逆洗配管26及び第1の薬剤供給配管28を介して、濾過水配管4及び逆洗配管26内の洗浄水17に第1の薬剤を混合した混合水を第1の薬剤貯留槽22へ吸引移送する。 If the cleaning blower 38 cannot be used, after closing the cleaning water supply valve 25, the first backwash valve 32, the second backwash valve 36, the first air supply valve 31, and the first chemical supply valve 30 is opened to start the first chemical supply pump 33 (suction device), and the filtered water pipe 4 and the backwash are passed through the filtered water pipe 4, the first backwash pipe 26 and the first chemical supply pipe 28. The mixed water in which the first chemical is mixed with the washing water 17 in the pipe 26 is suction-transferred to the first chemical storage tank 22.
このような薬液の排除を行うことにより、配管内に残存した薬液を効率的に排除し、更には薬液と薬液排除に使われる洗浄水が相互に反応することを防止することができる。従って第2の薬液を含有する混合水の濃度を維持しながら混合水を濾過膜に供することができる。
即ち薬液排除方法として洗浄水17のみを用いた場合について考える。薬液排除方法として洗浄水17を用いた場合、洗浄水17の水質が悪いと(洗浄水17中に懸濁物質または溶存態有機物が含まれている)、洗浄水17中の懸濁物質または溶存態有機物が(第1の薬剤を混合した混合水の排除後に供給する)第2の薬液と反応する可能性がある。逆洗配管内で洗浄水17と薬剤とが混合され、混合水が生成される段階と異なり、配管内に残存した薬液を排除する段階ではできるだけクリーンな状態にする必要がある。そして洗浄水17と第2の薬液が配管内で反応してしまうと、第2の薬液の濃度が濾過膜へ届く前に低下してしまい、濾過膜の洗浄能力の低下に繋がる恐れがある。このような現象を防ぐために空気による洗浄、更には吸引移送を行う。
By eliminating such a chemical solution, it is possible to efficiently eliminate the chemical solution remaining in the pipe and further prevent the chemical solution and the washing water used for removing the chemical solution from reacting with each other. Therefore, the mixed water can be applied to the filtration membrane while maintaining the concentration of the mixed water containing the second chemical solution.
That is, consider the case where only the washing water 17 is used as the method for removing the chemical solution. When the washing water 17 is used as a method for removing the chemical solution, if the water quality of the washing water 17 is poor (suspended solids or dissolved organic substances are contained in the washing water 17), the suspended solids or dissolved substances in the washing water 17 are contained. Suspended solids may react with the second drug solution (supplied after the elimination of the mixed water mixed with the first drug). Unlike the stage where the washing water 17 and the chemicals are mixed in the backwash pipe to generate the mixed water, it is necessary to keep the state as clean as possible at the stage where the chemical solution remaining in the pipe is removed. If the cleaning water 17 reacts with the second chemical solution in the pipe, the concentration of the second chemical solution decreases before it reaches the filtration membrane, which may lead to a decrease in the cleaning ability of the filtration membrane. In order to prevent such a phenomenon, cleaning with air and further suction transfer are performed.
また、薬液排除後に膜モジュール3から排出される第1の薬剤を含有する混合水は、被処理水槽2内に排出し、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膜モジュール3から排出される第1の薬剤を含有する混合水は、処理済液として別途回収して処理してもよい。 Further, the mixed water containing the first chemical discharged from the membrane module 3 after the chemical solution is removed can be discharged into the water tank 2 to be treated and used as the water 1 to be treated used for the filtration treatment. Alternatively, the mixed water containing the first chemical discharged from the membrane module 3 after the backflow cleaning may be separately collected and treated as a treated liquid.
次に洗浄水供給バルブ25及び第1の逆洗バルブ32を閉じた後、第2の逆洗バルブ36を開けて第2の薬剤供給ポンプ37を起動し、洗浄水槽18から洗浄水配管24、24B及び切換弁21を介して第2の逆洗配管27に洗浄水17を供給する。そして第2の薬剤供給バルブ34を開けて第2の薬剤供給ポンプ37を起動し、第2の薬剤貯留槽23から第2の薬剤供給配管29を介して第2の逆洗配管27に第2の薬剤を供給する。これにより第2の逆洗配管27内で洗浄水17と第2の薬剤とが混合され、混合水となる。なお図示していないが、第2の逆洗配管27には、洗浄水17と第2の薬剤とを均一に混合する装置(例えば、スタティックミキサ)を設けてもよい。そして第2の薬剤を含有する混合水を濾過水配管4を介して膜モジュール3に供給し、膜モジュール3中の濾過膜を逆流洗浄する。或いは第2の逆洗配管27に洗浄水17を収容する槽を設け、その槽内に第2の薬剤を供給して洗浄水17と第2の薬剤とを均一に混合し、この混合水をポンプで膜モジュール3に供給して膜モジュール3中の濾過膜を逆流洗浄してもよい。 Next, after closing the washing water supply valve 25 and the first backwash valve 32, the second backwash valve 36 is opened to start the second chemical supply pump 37, and the washing water pipe 24 from the washing water tank 18 The wash water 17 is supplied to the second backwash pipe 27 via the 24B and the switching valve 21. Then, the second drug supply valve 34 is opened to start the second drug supply pump 37, and the second drug storage tank 23 is connected to the second backwash pipe 27 via the second drug supply pipe 29. Supply the drug. As a result, the washing water 17 and the second chemical are mixed in the second backwash pipe 27 to become mixed water. Although not shown, the second backwash pipe 27 may be provided with a device (for example, a static mixer) that uniformly mixes the wash water 17 and the second chemical. Then, the mixed water containing the second chemical is supplied to the membrane module 3 via the filtered water pipe 4, and the filtered membrane in the membrane module 3 is backwashed. Alternatively, a tank for accommodating the washing water 17 is provided in the second backwash pipe 27, the second chemical is supplied into the tank, the washing water 17 and the second chemical are uniformly mixed, and the mixed water is mixed. The filtration membrane in the membrane module 3 may be backwashed by supplying the membrane module 3 with a pump.
なお上記濾過膜の洗浄装置では、薬剤を含有する2種の混合水を用いた場合について説明したが、薬剤を含有する3種以上の混合水を用いる場合、薬剤貯留槽を増加して、同様の方法にて洗浄処理を行うことができる。
濾過膜の洗浄装置を用いた洗浄処理が終了すると、第2の逆洗バルブ36、第1の逆洗バルブ32、洗浄水供給バルブ25及び濾過バルブ15を開き、濾過ポンプ16を起動し、被処理水1の濾過処理を再度行うことにより、被処理水1の濾過処理を連続的且つ効率的に行うことができる。
In the above-mentioned filtration membrane cleaning device, the case where two kinds of mixed water containing a drug is used has been described, but when three or more kinds of mixed water containing a drug are used, the drug storage tank is increased and the same applies. The cleaning process can be performed by the above method.
When the cleaning process using the filtration membrane cleaning device is completed, the second backwash valve 36, the first backwash valve 32, the washing water supply valve 25 and the filtration valve 15 are opened, the filtration pump 16 is started, and the subject is covered. By performing the filtration treatment of the treated water 1 again, the filtration treatment of the water to be treated 1 can be continuously and efficiently performed.
上記のような構成を有する濾過膜の洗浄装置によれば、複数の薬液を用いて濾過膜を洗浄する場合の薬液排除方法において、配管内に残存した薬液を効率的に排除しつつ、複数の薬液の濃度を維持しながら濾過膜に供することができる。また薬液排除において洗浄水による水洗以外の方法を選択できるので、洗浄水の節水ができる。
又濾過膜によって濾過された洗浄水と気体を交互に流通させることにより配管内の薬液を排除することもできる。このような方法は所謂「パルス洗浄」と呼ばれる洗浄方法のことであり、液体と気体を交互に流通させると、液体のみ又は気体のみを流通させた場合よりも、濾過膜または配管に対する洗浄能力が向上する。
According to the filtration membrane cleaning device having the above configuration, in the method for removing the chemical solution when cleaning the filtration membrane using a plurality of chemical solutions, a plurality of chemical solutions remaining in the pipe are efficiently removed. It can be applied to the filtration membrane while maintaining the concentration of the chemical solution. In addition, since a method other than washing with washing water can be selected for removing the chemical solution, the washing water can be saved.
It is also possible to eliminate the chemical solution in the pipe by alternately circulating the washing water and the gas filtered by the filtration membrane. Such a method is a cleaning method called "pulse cleaning", and when liquid and gas are alternately circulated, the cleaning ability for the filter membrane or the pipe is higher than when only liquid or gas is circulated. improves.
本実施の形態に係る薬液排除方法は、種類の異なる薬液の配管内での混合を避けるため、濾過膜を洗浄水17に第1の薬剤を混合した混合水で洗浄した後、配管内に残存した洗浄水17に第1の薬剤を混合した混合水を排除し、更に濾過膜を洗浄水17に第2の薬剤を混合した混合水で洗浄した後、配管内に残存した洗浄水17に第2の薬剤を混合した混合水を排除する方法である。この場合洗浄水の濁度が低い場合は洗浄水を用いて配管内に残存した薬液を排除し、洗浄水を供給できない場合は気体を用いて配管内に残存した薬液を排除し、気体供給装置を使用できない場合は吸引を用いて配管内に残存した薬液を排除するものである。 In the method for removing chemicals according to the present embodiment, in order to avoid mixing of different types of chemicals in the pipe, the filter membrane is washed with the mixed water in which the first chemical is mixed with the washing water 17, and then remains in the pipe. The mixed water in which the first chemical was mixed with the washed water 17 was removed, and the filter membrane was washed with the mixed water in which the second chemical was mixed with the washing water 17, and then the washing water 17 remaining in the pipe was used for the second. It is a method of removing the mixed water in which the two chemicals are mixed. In this case, if the turbidity of the washing water is low, wash water is used to remove the chemical solution remaining in the pipe, and if the washing water cannot be supplied, gas is used to remove the chemical solution remaining in the pipe, and the gas supply device. If it cannot be used, suction is used to remove the chemical solution remaining in the pipe.
本実施の形態に係る濾過膜の洗浄方法に用いられる混合水は、複数であれば特に限定されないが、混合水の数が多すぎると、各混合水に用いる薬剤の種類を多くしなければならない。そのため、本実施の形態に係る濾過膜の洗浄方法に用いられる混合水は、洗浄コストを低減する観点から、好ましくは2種又は3種、より好ましくは2種である。上記においては、2種の混合水を用いた濾過膜の洗浄方法を例に説明したが、3種以上の混合水を用いた濾過膜の洗浄方法を採用することもできる。 The mixed water used in the method for cleaning the filtration membrane according to the present embodiment is not particularly limited as long as it is plural, but if the number of mixed waters is too large, the types of chemicals used for each mixed water must be increased. .. Therefore, the mixed water used in the method for cleaning the filtration membrane according to the present embodiment is preferably 2 or 3 types, more preferably 2 types, from the viewpoint of reducing the cleaning cost. In the above, the method for cleaning the filtration membrane using two kinds of mixed water has been described as an example, but the method for cleaning the filtration membrane using three or more kinds of mixed water can also be adopted.
本実施の形態に係る濾過膜の洗浄方法は、洗浄水を濾過膜内に通水した後、洗浄水をそのまま膜内で保持してもよく、又は濾過膜を洗浄液に浸漬して保持してもよい。
本実施の形態に係る薬液排除に用いられる洗浄水は、洗浄水中の懸濁物質量に応じて洗浄水以外の薬液排除方法にリアルタイムで変更する必要がある。従って本実施の形態に係る薬液排除に用いられる洗浄水は、オンライン濁度計を用いて洗浄水中の濁度をリアルタイムに測定する必要がある。洗浄水中の濁度は、低い程好ましいが、好ましくは1NTUより下、より好ましくは0NTUである。
In the method for cleaning the filter membrane according to the present embodiment, after the cleaning water is passed through the filtration membrane, the cleaning water may be held in the membrane as it is, or the filtration membrane is immersed in the cleaning liquid and held. May be good.
The washing water used for removing the chemical solution according to the present embodiment needs to be changed in real time to a method for removing the chemical solution other than the washing water according to the amount of suspended solids in the washing water. Therefore, it is necessary to measure the turbidity of the washing water in real time using an online turbidity meter for the washing water used for removing the chemical solution according to the present embodiment. The lower the turbidity in the washing water, the more preferable, but it is preferably lower than 1 NTU, more preferably 0 NTU.
本実施の形態に係る薬液排除に用いられる気体は、毒性の低い気体を用いることが好ましいが、ボンベを必要とする気体を用いると、薬液排除に要するコストを抑制することができない。そのため、本実施の形態に係る薬液排除方法に用いられる気体は、ブロワで発生させた空気を用いることが好ましい。
また、本実施の形態に係る濾過膜の洗浄方法の対象となる濾過膜は、上水道、下水道、下水二次処理水、工業排水、海水、屎尿などの被処理水を濾過処理することによって汚濁物質が表面又は孔中に付着した状態の濾過膜である。
As the gas used for removing the chemical solution according to the present embodiment, it is preferable to use a gas having low toxicity, but if a gas requiring a cylinder is used, the cost required for removing the chemical solution cannot be suppressed. Therefore, it is preferable to use air generated by a blower as the gas used in the chemical solution removing method according to the present embodiment.
Further, the filter membrane to be the target of the filter membrane cleaning method according to the present embodiment is a pollutant by filtering water to be treated such as water supply, sewerage, secondary treated sewage water, industrial wastewater, seawater, and urine. Is a filtration film in a state where is adhered to the surface or in the pores.
本実施の形態の濾過膜の洗浄方法に用いることができる濾過膜の材質は、薬剤によって劣化しなければ特に限定されない。濾過膜の材質の例としては、ポリエチレン、ポリプロピレン、ポリブテンなどのポリオレフィンがある。又濾過膜の材質の例としては、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(FLUORINATED ETHYLENE PROPYLENE))、テトラフルオロエチレン-エチレン共重合体(ETFE(ETHYLENE TETRAFLUOROETHYLENE))、ポリクロロトリフルオロエチレン(PCTFE(POLYCHLOROTRIFLUOROETHYLENE))、クロロトリフルオロエチレン-エチレン共重合体(ECTFE(ETHYLENE CHLOROTRIFLUOROETHYLENE))、ポリフッ化ビニリデン(PVDF(POLYVINYLIDENE DIFLUORIDE))、ポリテトラフルオロエチレン(PTFE(POLYTETRAFLUOROETHYLENE))などのフッ素系樹脂化合物がある。又濾過膜の材質の例としては、酢酸セルロース、エチルセルロースなどのセルロース類、更にはセラミックが挙げられる。その中でも濾過膜の材質は、オゾンのような強い酸化剤に対する耐性に優れたフッ素系樹脂化合物であることが好ましい。また、濾過膜の材質は、上記の各物質を単独又は2種以上を組み合わせたものであってもよい。 The material of the filtration membrane that can be used in the method for cleaning the filtration membrane of the present embodiment is not particularly limited as long as it is not deteriorated by a chemical agent. Examples of materials for filtration membranes include polyolefins such as polyethylene, polypropylene and polybutene. Examples of the material of the filter membrane include tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP (FLUORINATED ETHYLENE PROPYLENE)), and tetrafluoroethylene-ethylene. Polymers (ETFE (ETHYLENE TETRAFLUOROETHYLENE)), polychlorotrifluoroethylene (PCTFE (POLYCHLOROTRIFLUOROETHYLENE)), chlorotrifluoroethylene-ethylene copolymer (ECTFE (ETHYLENE CHLOROTRIFLUOROETHYLENE) There are fluororesin compounds such as polytetrafluoroethylene (PTFE (POLYTETRAFLUOROETHYLENE)). Examples of the material of the filtration membrane include celluloses such as cellulose acetate and ethyl cellulose, and ceramics. Among them, the material of the filtration membrane is preferably a fluororesin compound having excellent resistance to a strong oxidizing agent such as ozone. Further, the material of the filtration membrane may be a single substance or a combination of two or more of the above substances.
濾過膜の種類は特に限定されず、精密濾過(MF(MICROFILTRATION MEMBRANE))膜、限外濾過(UF(ULTRAFILTRATION MEMBRANE))膜等の各種濾過膜を用いることができる。濾過膜の平均孔径は特に限定されないが、好ましくは0.001μm~1μm、より好ましくは0.01μm~0.1μmである。この範囲の平均孔径を有する濾過膜であれば、本実施の形態の濾過膜の洗浄方法により、被処理水と接する濾過膜の表面に付着した汚濁物質だけでなく、洗浄水と接する濾過膜の表面又は濾過膜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。濾過膜の形状は特に限定されず、円筒状、平膜状の形状とすることができる。その中でも、濾過膜の形状は円筒状であることが好ましい。なお濾過膜は、膜モジュール3に組み込まれていてもよく、膜モジュール3は、浸漬型、ケーシング型、モノリス型を採用することができる。また濾過膜の濾過方式は、全量濾過方式又はクロスフロー濾過方式のいずれのものでも用いることができる。 The type of the filtration membrane is not particularly limited, and various filtration membranes such as a microfiltration (MF (MICROFILTRATION MEMBRANE)) membrane and an ultrafiltration (UF (ULTRAFILTRATION MEMBRANE)) membrane can be used. The average pore size of the filtration membrane is not particularly limited, but is preferably 0.001 μm to 1 μm, and more preferably 0.01 μm to 0.1 μm. If the filtration membrane has an average pore size in this range, the filtration membrane cleaning method of the present embodiment can be used not only for pollutants adhering to the surface of the filtration membrane in contact with the water to be treated, but also for the filtration membrane in contact with the cleaning water. The pollutant that is chemically attached to the surface or the pores of the filtration membrane can be efficiently removed. The shape of the filtration membrane is not particularly limited, and can be a cylindrical shape or a flat membrane shape. Among them, the shape of the filtration membrane is preferably cylindrical. The filtration membrane may be incorporated in the membrane module 3, and the membrane module 3 may be an immersion type, a casing type, or a monolith type. Further, the filtration method of the filtration membrane can be either a total filtration method or a cross-flow filtration method.
濾過膜の通水方式としては、特に限定されず、濾過膜の外側に被処理水を流し、内側に洗浄水を流す外圧濾過方式、濾過膜の内側に被処理水を流し、外側に洗浄水を流す内圧濾過方式のいずれであってもよい。
洗浄水17に第1の薬剤を混合した混合水及び洗浄水17に第2の薬剤を混合した混合水としては、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ない。有機物を分解可能な薬液の例として、次亜塩素酸ナトリウム、過酸化水素、水酸化ナトリウム、オゾン水などが挙げられる。これらは、単独又は2種以上を組み合わせて用いることができる。
第1の薬剤を混合した薬液として洗浄水17に次亜塩素酸ナトリウム又は過酸化水素を溶解させた混合水を用いることができる。第2の薬剤を混合した薬液として洗浄水17にオゾンを溶解させた混合水を用いることができる。
The water flow method of the filter membrane is not particularly limited, and is an external pressure filtration method in which the water to be treated flows outside the filter membrane and the wash water flows inside, and the water to be treated flows inside the filter membrane and the wash water flows outside. It may be any of the internal pressure filtration methods in which water is flowed.
The mixed water in which the first chemical is mixed with the washing water 17 and the mixed water in which the second chemical is mixed with the washing water 17 are not particularly limited as long as they are substances capable of decomposing organic substances or inorganic substances. Examples of chemical solutions capable of decomposing organic substances include sodium hypochlorite, hydrogen peroxide, sodium hydroxide, ozone water and the like. These can be used alone or in combination of two or more.
As the chemical solution mixed with the first drug, mixed water in which sodium hypochlorite or hydrogen peroxide is dissolved in washing water 17 can be used. As the chemical solution in which the second drug is mixed, mixed water in which ozone is dissolved in the washing water 17 can be used.
また無機物を分解可能な物質として、塩酸、硫酸、硝酸などの無機酸、シュウ酸、クエン酸などの有機酸を用いることができる。これらも、単独又は2種以上を組み合わせて用いることができる。また、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種類以上組み合わせて用いることもできる。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種類以上組み合わせて用いる場合、どちらを第1の薬剤を混合した混合水又は第2の薬剤を混合した混合水として用いるかは特に限定されず、有機物を分解可能な物質を第1の薬剤を混合した混合水として用いた場合は無機物を分解可能な物質を第2の薬剤を混合した混合水として用い、無機物を分解可能な物質を第1の薬剤を混合した混合水として用いた場合は有機物を分解可能な物質を第2の薬剤を混合した混合水として用いればよい。 Further, as a substance capable of decomposing an inorganic substance, an inorganic acid such as hydrochloric acid, sulfuric acid or nitric acid, or an organic acid such as oxalic acid or citric acid can be used. These can also be used alone or in combination of two or more. Further, two or more kinds of substances capable of decomposing organic substances and substances capable of decomposing inorganic substances can be used in combination. When two or more kinds of substances capable of decomposing organic substances and substances capable of decomposing inorganic substances are used in combination, which one is used as the mixed water in which the first drug is mixed or the mixed water in which the second drug is mixed is particularly limited. Instead, when a substance capable of decomposing an organic substance is used as a mixed water mixed with a first agent, a substance capable of decomposing an inorganic substance is used as a mixed water mixed with a second agent, and a substance capable of decomposing an inorganic substance is used as a mixed water. When the mixed water in which the first drug is mixed is used, a substance capable of decomposing an organic substance may be used as the mixed water in which the second drug is mixed.
洗浄水中の薬液濃度は、特に限定されないが、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)では1.0g/L以上5.0g/L以下、水酸化ナトリウムでは1.0g/L以上4.0g/L以下が好ましい。オゾン水では5mg/L以上100mg/L以下が好ましく、より好ましくは20mg/L以上30mg/L以下である。無機物を分解可能な物質を用いる場合、塩酸、硫酸、硝酸では1.0g/L以上10.0g/L以下、シュウ酸では1.0g/L以上2.0g/L以下、クエン酸では1g/L以上10g/L以下が好ましい。薬液濃度が上記範囲よりも低いと、濾過膜に付着した汚濁物質の分解に時間を要する。また、洗浄水の必要量の増大に伴い、薬剤貯蔵槽の容量も増大する。一方、第1の薬剤を混合した混合水又は第2の薬剤を混合した混合水の濃度が上記の範囲よりも高いと、薬液の消費量が多くなるため、薬液に要するコストが増大する。 The concentration of the chemical solution in the washing water is not particularly limited, but when a substance capable of decomposing organic substances is used, sodium hypochlorite (effective chlorine concentration) is 1.0 g / L or more and 5.0 g / L or less, and sodium hydroxide is used. It is preferably 1.0 g / L or more and 4.0 g / L or less. For ozone water, it is preferably 5 mg / L or more and 100 mg / L or less, and more preferably 20 mg / L or more and 30 mg / L or less. When a substance capable of decomposing inorganic substances is used, 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. It is preferably L or more and 10 g / L or less. If the concentration of the chemical solution is lower than the above range, it takes time to decompose the pollutants adhering to the filtration membrane. In addition, as the required amount of wash water increases, the capacity of the drug storage tank also increases. On the other hand, if the concentration of the mixed water mixed with the first drug or the mixed water mixed with the second drug is higher than the above range, the consumption of the chemical solution increases, so that the cost required for the chemical solution increases.
薬液を含有する混合水を用いた濾過膜の洗浄時間は、特に限定されず、濾過膜に付着した汚濁物質の量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、シュウ酸又はクエン酸を用いる場合は5分~7分が好ましい。
洗浄時間は短い方が好ましく、洗浄時間が長くなると、総洗浄時間が長くなり、被処理水の濾過膜による濾過処理を中断する時間も長くなるため、濾過膜を濾過する水量が低下する。
即ち通常、下水及び廃水処理の濾過膜による濾過処理において、被処理水の濾過は一日中行っている。濾過膜の薬液洗浄は、その被処理水の濾過処理を停止して行うことになるため、洗浄時間が長くなれば長くなるほど、被処理水を濾過する時間が短くなることになる。つまり、被処理水を濾過する時間が短くなるため、濾過処理できる水量(洗浄水量)も少なくなる。
The cleaning time of the filtration membrane using the mixed water containing the chemical solution is not particularly limited, and may be appropriately set according to the amount of pollutants adhering to the filtration membrane. Generally, 90 minutes or less is preferable when sodium hypochlorite is used, and 5 to 7 minutes is preferable when oxalic acid or citric acid is used.
It is preferable that the washing time is short, and when the washing time is long, the total washing time is long and the time for interrupting the filtration treatment by the filtration membrane of the water to be treated is also long, so that the amount of water to be filtered through the filtration membrane is reduced.
That is, normally, in the filtration treatment using a filtration membrane for sewage and wastewater treatment, the water to be treated is filtered all day long. Since the chemical solution cleaning of the filtration membrane is performed by stopping the filtration treatment of the water to be treated, the longer the cleaning time, the shorter the time for filtering the water to be treated. That is, since the time for filtering the water to be treated is shortened, the amount of water that can be filtered (the amount of washing water) is also reduced.
薬液を含有する混合水の膜面透過流束(膜の面積当たりの透水量)は、特に限定されない。一般的には、濾過膜末端まで充填可能な流束を確保できればよく、特にオゾン水を用いる場合は、搬送中の濃度維持が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/m/h)以下、オゾン水を用いる場合は50LMH(L/m/h)以下、より好ましくは30LMH(L/m/h)以下である。膜面透過流束が高すぎると、混合水の必要量の増大に伴い薬剤に要するコストが増大する。また、薬剤貯蔵槽の容量も増大する。膜面透過流束が低すぎると、混合水が濾過膜末端まで充填されず、濾過膜に付着した汚濁物質を分解できなくなる。また、オゾン水を用いる場合は、搬送中に濃度が低下する。 The membrane surface permeation flux (water permeation amount per membrane area) of the mixed water containing the chemical solution is not particularly limited. In general, it is sufficient to secure a flux that can be filled up to the end of the filtration membrane, and particularly when ozone water is used, it is sufficient to secure a flux that can maintain the concentration during transportation. Specifically, when sodium hypochlorite is used, it is 6 LMH (L / m 2 / h) or less, when ozone water is used, it is 50 LMH (L / m 2 / h) or less, and more preferably 30 LMH (L / h). m 2 / h) or less. If the permeation flux is too high, the cost of the drug increases as the required amount of mixed water increases. It also increases the capacity of the drug storage tank. If the permeation flux on the membrane surface is too low, the mixed water will not be filled to the end of the filtration membrane, and the pollutants adhering to the filtration membrane cannot be decomposed. When ozone water is used, the concentration decreases during transportation.
薬液排除に用いられる方法としては、一般的には洗浄水、気体が用いられ、更には吸引方法が用いられるが、その中でも気体を用いることが好ましく、洗浄水を用いることがより好ましい。濾過膜が破断していない状態、すなわち被処理水中の懸濁物質又は溶存態有機物が洗浄水に流出していない状態では、洗浄水の濁度は一般的に0NTUを示す。一方、濾過膜が破断している状態、すなわち被処理水中の懸濁物質又は溶存態有機物が洗浄水に流出している状態では、洗浄水の濁度は一般的に1NTU以上を示す。 As the method used for removing the chemical solution, washing water and gas are generally used, and further, a suction method is used. Among them, gas is preferably used, and washing water is more preferable. In the state where the filtration membrane is not broken, that is, the suspended solids or dissolved organic substances in the water to be treated do not flow out into the washing water, the turbidity of the washing water generally shows 0 NTU. On the other hand, when the filtration membrane is broken, that is, when suspended solids or dissolved organic substances in the water to be treated are flowing out into the washing water, the turbidity of the washing water generally shows 1 NTU or more.
被処理水中の懸濁物質又は溶存態有機物が流出した洗浄水を、配管内に残存した薬液の排除方法として用いると、薬液と洗浄水中の懸濁物質、溶存態有機物が反応し、薬液の濃度を維持することができない。即ち逆洗配管内で洗浄水17と薬剤とが混合され、混合水が生成される段階と異なり、配管内に残存した薬液を排除する段階ではできるだけクリーンな状態にする必要がある。そのため、薬液排除方法の選択においては、洗浄水を優先的に選択するが、洗浄水の濁度が1NTU以上の場合は気体を選択する。また、気体の供給が困難である場合は、吸引方法を選択する。 When the washing water from which the suspended solids or dissolved organic substances in the water to be treated have flowed out is used as a method for removing the chemical solution remaining in the pipe, the chemical solution reacts with the suspended solids or dissolved organic substances in the washing water, and the concentration of the chemical solution is concentrated. Cannot be maintained. That is, unlike the stage where the washing water 17 and the chemicals are mixed in the backwash pipe to generate the mixed water, it is necessary to keep the state as clean as possible at the stage where the chemical solution remaining in the pipe is removed. Therefore, in the selection of the chemical solution exclusion method, the washing water is preferentially selected, but when the turbidity of the washing water is 1 NTU or more, a gas is selected. If it is difficult to supply gas, select a suction method.
薬液排除を行うタイミングは、第1の薬剤を混合した混合水の供給よりも前の段階、第1の薬剤を混合した混合水と第2の薬剤を混合した混合水の供給の間、更には第2の薬剤を混合した混合水の供給の後が好ましいが、その中でも第1の薬剤を混合した混合水の供給と第2の薬剤を混合した混合水の供給の間であることがより好ましい。
薬液排除の実施方向は、第1の薬剤を混合した混合水及び第2の薬剤を混合した混合水と同じ流れ方向、第1の薬剤を混合した混合水及び第2の薬剤を混合した混合水と逆の流れ方向のいずれであってもよいが、第1の薬剤を混合した混合水及び第2の薬剤を混合した混合水と同じ流れ方向であることが好ましい。
即ち薬液排除を実施する方向は2つあり、一つは濾過膜の二次側から一次側に向かう方向(薬液の流れと同じ方向)と、もう一つが濾過膜の一次側から二次側に向かう方向(被処理水1が濾過される方向と同じ方向)である。薬液の排除にあたり、どちらの方向でも良いが、薬液と同じ方向(濾過膜の二次側から一次側に向かう方向)の方が、配管内及び濾過膜内部の薬液を排除しきれるため好ましい。
The timing of removing the chemical solution is before the supply of the mixed water mixed with the first drug, between the supply of the mixed water mixed with the first drug and the mixed water mixed with the second drug, and further. It is preferable after the supply of the mixed water mixed with the second agent, but more preferably between the supply of the mixed water mixed with the first agent and the supply of the mixed water mixed with the second agent. ..
The direction of chemical solution exclusion is the same flow direction as the mixed water mixed with the first drug and the mixed water mixed with the second drug, the mixed water mixed with the first drug and the mixed water mixed with the second drug. The flow direction may be opposite to that of the above, but it is preferable that the flow direction is the same as that of the mixed water in which the first agent is mixed and the mixed water in which the second agent is mixed.
That is, there are two directions for removing the chemical solution, one is from the secondary side to the primary side of the filtration membrane (the same direction as the flow of the chemical solution), and the other is from the primary side to the secondary side of the filtration membrane. The direction (the same direction as the direction in which the water to be treated 1 is filtered). In removing the chemical solution, either direction may be used, but the same direction as the chemical solution (direction from the secondary side to the primary side of the filtration membrane) is preferable because the chemical solution in the pipe and the inside of the filtration membrane can be completely eliminated.
また、薬液排除により排除した薬液の処理方法については特に限定されない。第1の薬剤を混合した混合水及び第2の薬剤を混合した混合水と同じ流れ方向の場合は、濾過膜又は反応槽(被処理水槽2)へ排除することが好ましいが、濾過膜へ排除することがより好ましい。
また、第1の薬剤を混合した混合水及び第2の薬剤を混合した混合水と逆の流れ方向の場合は、薬剤貯蔵槽又は処理水槽(洗浄水槽18)へ排除することが好ましいが、薬剤貯蔵槽へ排除することがより好ましい。
薬液排除の時間は、一般的には第1の薬剤を混合した混合水及び第2の薬剤を混合した混合水が通水する箇所の配管内容量以上の流量を確保できる排除時間であればよい。排除時間が短いと、配管内に残存した薬液を排除しきれないため、薬剤を含有する混合水を供給した際に薬剤の濃度が低下する。排除時間が長いと、総洗浄時間が長くなるため、被処理水の濾過膜による濾過処理を中断する時間も長くなり、濾過膜による処理される水量が低下する。
Further, the method for treating the chemical solution excluded by the chemical solution exclusion is not particularly limited. When the flow direction is the same as that of the mixed water mixed with the first drug and the mixed water mixed with the second drug, it is preferable to eliminate the water in the filtration membrane or the reaction tank (water tank 2 to be treated), but it is excluded in the filtration membrane. It is more preferable to do so.
Further, in the case of the flow direction opposite to that of the mixed water in which the first drug is mixed and the mixed water in which the second drug is mixed, it is preferable to remove the drug into the drug storage tank or the treated water tank (washing water tank 18). It is more preferable to remove it into the storage tank.
Generally, the time for removing the chemical solution may be any time as long as it can secure a flow rate equal to or larger than the capacity of the pipe at the place where the mixed water mixed with the first drug and the mixed water mixed with the second drug pass. .. If the removal time is short, the chemical solution remaining in the pipe cannot be completely removed, so that the concentration of the chemical is lowered when the mixed water containing the chemical is supplied. If the exclusion time is long, the total washing time is long, so that the time for interrupting the filtration treatment of the water to be treated by the filtration membrane is also long, and the amount of water treated by the filtration membrane is reduced.
薬液排除の流速は、配管内に残存している薬液の量に応じて適宜設定すればよい。排除流速は速い方が好ましく、排除流速が遅くなると、排除流速により生じるせん断応力の低下により、配管に付着した薬液を排除しきれなくなるため、薬剤を含有する混合水を供給した際に薬液の濃度が低下する。
薬液排除の制御方法は、濾過膜と第2の逆洗バルブ36の間にある積算流量計13を用いて、薬液排除に用いられる流体の積算流量を測定することにより制御する。濾過膜と第2の逆洗バルブ36の間にある積算流量計13の値が、第1の薬剤を混合した混合水及び第2の薬剤を混合した混合水が通水する箇所の配管内容量以上になった場合に薬液排除工程を終了することが好ましい。又排除される薬液の粘度が2cP(mPa・s)ならば配管内容量の2倍、3cP(mPa・s)ならば配管内容量の3倍以上になった場合に薬液排除工程を終了することがより好ましい。また、薬液排除方法、排除時間及び排除流速は、第1の薬剤を混合した混合水と第2の薬剤を混合した混合水で差異を設けてもよい。
The flow velocity for removing the chemical solution may be appropriately set according to the amount of the chemical solution remaining in the pipe. It is preferable that the exclusion flow velocity is high, and if the exclusion flow velocity is slow, the chemical solution adhering to the pipe cannot be completely removed due to the decrease in shear stress caused by the exclusion flow rate. Decreases.
The chemical solution exclusion control method is controlled by measuring the integrated flow rate of the fluid used for chemical solution exclusion using an integrated flow meter 13 located between the filtration membrane and the second backwash valve 36. The value of the integrated flow meter 13 between the filtration membrane and the second backwash valve 36 is the capacity of the pipe where the mixed water mixed with the first chemical and the mixed water mixed with the second chemical pass. When the above is reached, it is preferable to end the chemical solution exclusion step. If the viscosity of the chemical solution to be excluded is 2 cP (mPa · s), it is twice the capacity of the pipe, and if it is 3 cP (mPa · s), it is 3 times or more the capacity of the pipe, the chemical solution removal step is terminated. Is more preferable. Further, the chemical solution exclusion method, the exclusion time, and the exclusion flow rate may be different between the mixed water in which the first drug is mixed and the mixed water in which the second drug is mixed.
本実施形態においては、複数の薬剤を用いて濾過膜を洗浄する際に、種類の異なる薬剤の配管内での混合を避けるため、第1の薬剤を含有する混合水を用いた濾過膜の洗浄と、第2の薬剤を含有する混合水を用いた濾過膜の洗浄との間に薬液排除工程を導入し、配管内に残存した薬液を排除するものである。そして濾過膜を通過した洗浄水17の濁度が低い場合は洗浄水17を用いて配管内に残存した薬液を排除し、洗浄水17の濁度が高い場合は気体を用いて配管内に残存した薬液を排除し、気体を供給できない場合は吸引を用いて配管内に残存した薬液を排除するものである。
これにより複数の薬液を用いて濾過膜を洗浄する場合に、配管内に残存した薬剤を効率的に排除しつつ、薬液同士が反応することを防止し、複数の薬液の濃度を維持しながら濾過膜に供することができる。また、薬液排除において濾過膜を通過した洗浄水による水洗以外の方法を選択できることで、洗浄水の節水ができる。
In the present embodiment, when the filtration membrane is washed with a plurality of chemicals, the filtration membrane is washed with mixed water containing the first chemical in order to avoid mixing of different kinds of chemicals in the pipe. A chemical solution removing step is introduced between the cleaning of the filtration membrane with the mixed water containing the second chemical, and the chemical solution remaining in the pipe is removed. When the turbidity of the washing water 17 that has passed through the filtration membrane is low, the washing water 17 is used to remove the chemical solution remaining in the pipe, and when the turbidity of the washing water 17 is high, gas is used to remain in the pipe. When the gas cannot be supplied, the chemical solution remaining in the pipe is eliminated by using suction.
As a result, when the filtration membrane is washed with a plurality of chemical solutions, the chemicals remaining in the piping are efficiently removed, the chemical solutions are prevented from reacting with each other, and the filtration is performed while maintaining the concentration of the multiple chemical solutions. Can be applied to the membrane. In addition, the washing water can be saved by selecting a method other than washing with washing water that has passed through the filtration membrane for removing the chemical solution.
実施の形態2.
図2は実施の形態2に係る濾過膜の洗浄装置を備える水処理システムを示す概念図である。なお、本実施の形態に係る濾過膜の洗浄装置を備える水処理システムの基本的な構成は、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと同じであるため、相違点のみ説明する。また、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと同様の構成については、同一符号が付されている。
Embodiment 2.
FIG. 2 is a conceptual diagram showing a water treatment system including the filtration membrane cleaning device according to the second embodiment. Since the basic configuration of the water treatment system including the filter membrane cleaning device according to the present embodiment is the same as that of the water treatment system including the filter membrane cleaning device according to the first embodiment, only the differences are obtained. explain. Further, the same reference numerals are given to the same configurations as those of the water treatment system including the filtration membrane cleaning device according to the first embodiment.
図2において、本実施の形態に係る濾過膜の洗浄装置を備える水処理システムは、第2の薬剤を混合した混合水としてオゾンを用いる場合に適した構造を有している。すなわち、本実施の形態に係る濾過膜の洗浄装置を備える水処理システムは、第2の逆洗バルブ36で分岐された第2の逆洗配管27にオゾン水生成塔45が接続されている点で、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと異なる。オゾン水生成塔45の底部には散気装置44が配置されており、散気装置44にはオゾン供給配管43を介してオゾン発生器42が接続されている。オゾン発生器42に供給されるオゾン原料としては、特に限定されず、例えば、液体酸素、又はPSA(PRESSURE SWING ADSORPTION)若しくはPVSA(PRESSURE VACUUM SWING ADSORPTION)で生成した酸素を用いることができる。 In FIG. 2, the water treatment system including the filtration membrane cleaning device according to the present embodiment has a structure suitable for using ozone as the mixed water mixed with the second chemical. That is, in the water treatment system including the filtration membrane cleaning device according to the present embodiment, the ozone water generation tower 45 is connected to the second backwash pipe 27 branched by the second backwash valve 36. Therefore, it is different from the water treatment system provided with the filtration membrane cleaning device according to the first embodiment. An air diffuser 44 is arranged at the bottom of the ozone water generation tower 45, and an ozone generator 42 is connected to the air diffuser 44 via an ozone supply pipe 43. The ozone raw material supplied to the ozone generator 42 is not particularly limited, and for example, liquid oxygen or oxygen generated by PSA (PRESSURE SWING ADSORPTION) or PVSA (PRESSURE VACUUM SWING ADSORPTION) can be used.
このような構造を有する水処理システムでは、洗浄水17にオゾン(第2の薬剤)を混入する混合水を用いて逆流洗浄を行う際に、切換弁20、切換弁21及び第2の薬剤供給バルブ34を開き、逆洗ポンプ19を起動させ、洗浄水槽18から洗浄水配管24、24B及び第2の薬剤供給バルブ34を介してオゾン水生成塔45に洗浄水17を供給する。更にオゾン発生器42で発生させたオゾンガスをオゾン供給配管43を介して散気装置44から供給することにより、オゾン水生成塔45内で、洗浄水17にオゾンを混入した混合水としてのオゾン水を生成させる。そして、オゾン水生成塔45内で生成したオゾン水を第2の逆洗配管27及び濾過水配管4を介して膜モジュール3に供給し、膜モジュール3中の濾過膜を逆流洗浄する。更に本実施形態による水処理システムにおいては、排オゾン配管46、排オゾン処理設備47及び処理オゾン配管48が設けられている。 In a water treatment system having such a structure, when backflow cleaning is performed using mixed water in which ozone (second chemical) is mixed with the cleaning water 17, the switching valve 20, the switching valve 21, and the second chemical are supplied. The valve 34 is opened, the backwash pump 19 is started, and the wash water 17 is supplied from the wash water tank 18 to the ozone water generation tower 45 via the wash water pipes 24 and 24B and the second chemical supply valve 34. Further, by supplying the ozone gas generated by the ozone generator 42 from the air diffuser 44 via the ozone supply pipe 43, ozone water as a mixed water in which ozone is mixed with the washing water 17 in the ozone water generation tower 45. To generate. Then, the ozone water generated in the ozone water generation tower 45 is supplied to the membrane module 3 via the second backwash pipe 27 and the filtered water pipe 4, and the filtered membrane in the membrane module 3 is backwashed. Further, in the water treatment system according to the present embodiment, the ozone exhaust pipe 46, the ozone exhaust treatment equipment 47, and the treated ozone pipe 48 are provided.
このようにオゾン水生成塔45を設けることにより、オゾン水を効率良く生成させることができる。また、図2ではオゾンガスの供給装置として散気装置44を用いた場合を例示したが、オゾンガスと洗浄水17とを接触させたオゾン水を生成し得る装置であれば特に限定されない。例えば、エジェクタ式、機械攪拌式、下方注入式などのオゾンガスの供給装置を用いることができる。なお、図示していないが、全てのポンプ、バルブ、並びに切換弁は、制御装置に接続されおり、この制御装置により、全てのポンプ、バルブ、並びに切換弁の動作が制御される。 By providing the ozone water generation tower 45 in this way, ozone water can be efficiently generated. Further, although FIG. 2 illustrates the case where the air diffuser 44 is used as the ozone gas supply device, the device is not particularly limited as long as it can generate ozone water in which the ozone gas and the cleaning water 17 are in contact with each other. For example, an ozone gas supply device such as an ejector type, a mechanical stirring type, or a downward injection type can be used. Although not shown, all pumps, valves, and switching valves are connected to a control device, and the operation of all pumps, valves, and switching valves is controlled by this control device.
また、本実施の形態の濾過膜の洗浄装置では、オゾンを第2の薬剤として混合した混合水として用いた場合について説明したが、オゾンとオゾン以外の薬剤のどちらを第1の薬剤として混合した混合水又は第2の薬剤として混合した混合水として用いるかは特に限定されず、オゾンを第1の薬剤として混合した混合水として用いた場合はオゾン以外の薬剤を第2の薬剤として混合した混合水として用いればよい。 Further, in the filter membrane cleaning device of the present embodiment, the case where ozone is used as the mixed water mixed as the second chemical has been described, but either ozone or a chemical other than ozone is mixed as the first chemical. Whether it is used as mixed water or mixed water mixed as a second drug is not particularly limited, and when ozone is used as a mixed water mixed as a first drug, a drug other than ozone is mixed as a second drug. It may be used as water.
実施の形態3.
図3は実施の形態3に係る濾過膜の洗浄装置を備える水処理システムを示す概念図である。なお、本実施の形態に係る濾過膜の洗浄装置を備える水処理システムの基本的な構成は、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと同じであるため、相違点のみ説明する。また、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと同様の構成については、同一符号が付されている。
Embodiment 3.
FIG. 3 is a conceptual diagram showing a water treatment system including the filtration membrane cleaning device according to the third embodiment. Since the basic configuration of the water treatment system including the filter membrane cleaning device according to the present embodiment is the same as that of the water treatment system including the filter membrane cleaning device according to the first embodiment, only the differences are obtained. explain. Further, the same reference numerals are given to the same configurations as those of the water treatment system including the filtration membrane cleaning device according to the first embodiment.
図3において、本実施の形態に係る濾過膜の洗浄装置を備える水処理システムは、逆洗ポンプ19の代わりに給水配管49が設けられている点で、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと異なる。給水配管49は、切換弁20で分岐された洗浄水配管24Bを介して第1の逆洗配管26及び第2の逆洗配管27に接続されている。また、本実施の形態に係る給水配管49から供給する水は、濁度が1NTUより下であれば特に限定されない。例として、水道水、地下水、貯水池水、表流水、伏流水、湖沼水、海水が挙げられる。 In FIG. 3, the water treatment system including the filtration membrane cleaning device according to the present embodiment cleans the filtration membrane according to the first embodiment in that a water supply pipe 49 is provided instead of the backwash pump 19. It is different from the water treatment system equipped with the device. The water supply pipe 49 is connected to the first backwash pipe 26 and the second backwash pipe 27 via the wash water pipe 24B branched by the switching valve 20. Further, the water supplied from the water supply pipe 49 according to the present embodiment is not particularly limited as long as the turbidity is lower than 1 NTU. Examples include tap water, groundwater, reservoir water, surface water, underground water, lake water, and seawater.
このような構造を有する水処理システムでは、給水配管49から薬液排除を行う場合、切換弁20、洗浄水供給バルブ25、第1の逆洗バルブ32及び第2の逆洗バルブ36を開け水を供給する。又は切換弁20、切換弁21、第1の薬剤供給バルブ30、第1の空気供給バルブ31、第1の逆洗バルブ32及び第2の逆洗バルブ36を開け水を供給する。又は切換弁20、切換弁21、第2の薬剤供給バルブ34、第2の空気供給バルブ35及び第2の逆洗バルブ36を開け水を供給する。このように給水配管49を設けることにより、洗浄水を節水しながら薬液排除を効率良く行うことができる。 In a water treatment system having such a structure, when the chemical solution is removed from the water supply pipe 49, the switching valve 20, the washing water supply valve 25, the first backwash valve 32 and the second backwash valve 36 are opened to release water. Supply. Alternatively, the switching valve 20, the switching valve 21, the first chemical supply valve 30, the first air supply valve 31, the first backwash valve 32, and the second backwash valve 36 are opened to supply water. Alternatively, the switching valve 20, the switching valve 21, the second chemical supply valve 34, the second air supply valve 35, and the second backwash valve 36 are opened to supply water. By providing the water supply pipe 49 in this way, it is possible to efficiently remove the chemical solution while saving the washing water.
実施の形態4.
図4は実施の形態4に係る濾過膜の洗浄装置を備える水処理システムを示す概念図である。なお、本実施の形態に係る濾過膜の洗浄装置を備える水処理システムの基本的な構成は、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと同じであるため、相違点のみ説明する。また、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと同様の構成については、同一符号が付されている。
Embodiment 4.
FIG. 4 is a conceptual diagram showing a water treatment system including the filtration membrane cleaning device according to the fourth embodiment. Since the basic configuration of the water treatment system including the filter membrane cleaning device according to the present embodiment is the same as that of the water treatment system including the filter membrane cleaning device according to the first embodiment, only the differences are obtained. explain. Further, the same reference numerals are given to the same configurations as those of the water treatment system including the filtration membrane cleaning device according to the first embodiment.
図4において、本実施の形態に係る濾過膜の洗浄装置を備える水処理システムは、洗浄ブロワ38の代わりに気体供給装置としてのガスボンベ50が設けられている点で、実施の形態1に係る濾過膜の洗浄装置を備える水処理システムと異なる。ガスボンベ50は、第1の空気供給配管39及び第1の空気供給バルブ31で分岐された第1の逆洗配管26に接続されている。また、ガスボンベ50は、第2の空気供給配管40及び第2の空気供給バルブ35で分岐された第2の逆洗配管27に接続されている。
また、本実施の形態に係るガスボンベ50から供給する気体は、人体に毒性がなけ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。例として、酸素、窒素、二酸化炭素、炭酸ガスが挙げられる。
In FIG. 4, the water treatment system including the filtration membrane cleaning device according to the present embodiment is provided with a gas cylinder 50 as a gas supply device instead of the cleaning blower 38, and the filtration according to the first embodiment is provided. It differs from a water treatment system equipped with a membrane cleaning device. The gas cylinder 50 is connected to the first backwash pipe 26 branched by the first air supply pipe 39 and the first air supply valve 31. Further, the gas cylinder 50 is connected to the second backwash pipe 27 branched by the second air supply pipe 40 and the second air supply valve 35.
Further, the gas supplied from the gas cylinder 50 according to the present embodiment is not particularly limited as long as it is not toxic to the human body, and a substance known in the art can be used. Examples include oxygen, nitrogen, carbon dioxide and carbon dioxide.
このような構造を有する水処理システムでは、ガスボンベ50により薬液排除を行う場合、第1の空気供給バルブ31、第1の逆洗バルブ32及び第2の逆洗バルブ36を開け、気体を供給する。又は第2の空気供給バルブ35及び第2の逆洗バルブ36を開け、気体を供給する。このようにガスボンベ50を設けることにより、空気以外の気体を用いて薬液排除を行うことができる。そのため空気または酸素を用いることのできない嫌気及び無酸素環境下における膜処理においても、気体を用いた薬液排除を行うことができる。また嫌気及び無酸素環境下において、本実施の形態に係る濾過膜の洗浄装置を実施する場合は、酸素の供給に係る散気装置8、空気供給配管11及び膜面曝気ブロワ12を省略する。 In a water treatment system having such a structure, when the chemical solution is removed by the gas cylinder 50, the first air supply valve 31, the first backwash valve 32 and the second backwash valve 36 are opened to supply gas. .. Alternatively, the second air supply valve 35 and the second backwash valve 36 are opened to supply gas. By providing the gas cylinder 50 in this way, the chemical solution can be removed using a gas other than air. Therefore, even in the membrane treatment in an anaerobic and anoxic environment where air or oxygen cannot be used, the chemical solution using gas can be removed. Further, when the filter membrane cleaning device according to the present embodiment is implemented in an anaerobic and oxygen-free environment, the air diffuser 8, the air supply pipe 11, and the membrane aeration blower 12 related to the supply of oxygen are omitted.
そして気体の供給に用いるガスボンベ50を用いる場合はガスボンベ50の圧力に応じて、薬液排除方法を選択できる。更にはエアーポンプを用いる場合はエアーポンプの圧力に応じて、薬液排除方法を選択できる。例えば、ガスボンベ50の残圧が少なくなると、圧力計14の圧力が低下する。また、エアーポンプも故障または配管の漏れが生じた場合、やはり圧力計14の圧力が低下する。このような不具合が生じた場合でも、他の薬液排除方法を選択できるため、薬液排除に支障をきたさない。
即ち気体供給装置から供給される気体の圧力が基準値よりも低い場合、洗浄水17を用いて配管内に残存した薬液を排除するか、あるいは吸引装置により配管内に残存した薬液を薬剤貯留槽22、23へ吸引移送するかのうちのいずれか1つの方法を選択するものである。
When the gas cylinder 50 used for supplying the gas is used, the chemical elimination method can be selected according to the pressure of the gas cylinder 50. Furthermore, when an air pump is used, a chemical solution elimination method can be selected according to the pressure of the air pump. For example, when the residual pressure of the gas cylinder 50 decreases, the pressure of the pressure gauge 14 decreases. In addition, if the air pump also fails or a pipe leaks, the pressure of the pressure gauge 14 also drops. Even if such a problem occurs, another chemical solution exclusion method can be selected, so that the chemical solution elimination is not hindered.
That is, when the pressure of the gas supplied from the gas supply device is lower than the reference value, the chemical solution remaining in the pipe is removed by using the washing water 17, or the chemical solution remaining in the pipe is removed by the suction device in the chemical storage tank. One of the methods of suction transfer to 22 and 23 is selected.
 本願は、様々な例示的な実施の形態及び実施例が記載されているが、1つ、または複数の実施の形態に記載された様々な特徴、態様、及び機能は特定の実施の形態の適用に限られるのではなく、単独で、または様々な組み合わせで実施の形態に適用可能である。
従って、例示されていない無数の変形例が、本願に開示される技術の範囲内において想定される。例えば、少なくとも1つの構成要素を変形する場合、追加する場合または省略する場合、さらには、少なくとも1つの構成要素を抽出し、他の実施の形態の構成要素と組み合わせる場合が含まれるものとする。
Although the present application describes various exemplary embodiments and examples, the various features, embodiments, and functions described in one or more embodiments are applications of a particular embodiment. It is not limited to, but can be applied to embodiments alone or in various combinations.
Therefore, innumerable variations not illustrated are envisioned within the scope of the techniques disclosed in the present application. For example, it is assumed that at least one component is modified, added or omitted, and further, at least one component is extracted and combined with the components of other embodiments.
1 被処理水、2 被処理水槽、3 膜モジュール、13 積算流量計、17 洗浄水、18 洗浄水槽、22 第1の薬剤貯留槽、23 第2の薬剤貯留槽、33 第1の薬剤供給ポンプ、37 第2の薬剤供給ポンプ、38 洗浄ブロワ。 1 Water to be treated, 2 Water tank to be treated, 3 Membrane module, 13 Integrated flow meter, 17 Wash water, 18 Wash water tank, 22 1st drug storage tank, 23 2nd drug storage tank, 33 1st drug supply pump , 37 Second drug supply pump, 38 Cleaning blower.

Claims (8)

  1. 被処理水を収容する被処理水槽と、
    前記被処理水槽に設置されるとともに前記被処理水を濾過処理する濾過膜を有する膜モジュールと、
    前記濾過膜を洗浄するための複数の薬液をそれぞれ供給する複数の薬液供給部と、
    前記膜モジュールで濾過処理された濾過水であって、前記薬液供給部と前記被処理水槽を接続する配管内に残存した前記薬液を排除するために用いられる洗浄水を収容する洗浄水槽と、
    前記配管内に残存した前記薬液を排除するために用いられる気体を供給する気体供給装置と、
    前記配管に設置されるとともに、前記薬液の排除に用いられる前記洗浄水または前記気体の積算流量を測定する積算流量計とを備え、
    前記積算流量計の値が、前記配管における配管内容量以上になった場合に前記薬液の排除を終了する水処理システム。
    A water tank to be treated and a water tank to be treated
    A membrane module having a filtration membrane installed in the water tank to be treated and filtering the water to be treated,
    A plurality of chemical solution supply units for supplying a plurality of chemical solutions for cleaning the filtration membrane, and
    A washing water tank containing the washing water filtered by the membrane module and used for removing the washing water remaining in the pipe connecting the chemical solution supply unit and the water tank to be treated.
    A gas supply device that supplies a gas used for removing the chemical solution remaining in the pipe, and a gas supply device.
    It is provided with an integrated flow meter installed in the pipe and measuring the integrated flow rate of the washing water or the gas used for removing the chemical solution.
    A water treatment system that ends the removal of the chemical solution when the value of the integrated flow meter exceeds the capacity of the pipe in the pipe.
  2. 前記配管内に残存した前記薬液を前記薬液供給部へ吸引移送するための吸引装置を備えた請求項1記載の水処理システム。 The water treatment system according to claim 1, further comprising a suction device for suction-transferring the chemical solution remaining in the pipe to the chemical solution supply unit.
  3. 前記洗浄水の濁度が濁度設定値よりも低い場合は前記洗浄水を用いて前記配管内に残存した前記薬液を排除し、
    前記洗浄水の濁度が前記濁度設定値以下の場合は前記気体供給装置により前記気体を供給するか、あるいは前記気体供給装置が使用できない場合には前記吸引装置により前記配管内に残存した前記薬液を前記薬液供給部へ吸引移送する請求項2記載の水処理システム。
    When the turbidity of the washing water is lower than the turbidity set value, the washing water is used to remove the chemical solution remaining in the pipe.
    When the turbidity of the washing water is equal to or less than the turbidity set value, the gas is supplied by the gas supply device, or when the gas supply device cannot be used, the suction device remains in the pipe. The water treatment system according to claim 2, wherein the chemical solution is suction-transferred to the chemical solution supply unit.
  4. 前記洗浄水を用いることによる前記配管内に残存した前記薬液の排除と、前記気体供給装置により前記気体を供給することによる前記配管内に残存した前記薬液の排除とを交互に実行する請求項1記載の水処理システム。 Claim 1 in which the removal of the chemical solution remaining in the pipe by using the washing water and the removal of the chemical solution remaining in the pipe by supplying the gas by the gas supply device are alternately executed. The water treatment system described.
  5. 前記気体供給装置から供給される気体の圧力が基準値よりも低い場合、前記洗浄水を用いて前記配管内に残存した前記薬液を排除するか、あるいは前記吸引装置により前記配管内に残存した前記薬液を前記薬液供給部へ吸引移送するかのうちのいずれか1つを選択する請求項2記載の水処理システム。 When the pressure of the gas supplied from the gas supply device is lower than the reference value, the washing water is used to eliminate the chemical solution remaining in the pipe, or the suction device is used to remove the chemical solution remaining in the pipe. The water treatment system according to claim 2, wherein one of the two methods of suction-transferring the chemical solution to the chemical solution supply unit is selected.
  6. 前記薬液として前記洗浄水に次亜塩素酸ナトリウムを溶解させた混合水を用いる請求項1から請求項5のいずれか1項に記載の水処理システム。 The water treatment system according to any one of claims 1 to 5, wherein mixed water in which sodium hypochlorite is dissolved in the washing water is used as the chemical solution.
  7. 前記薬液として前記洗浄水に過酸化水素を溶解させた混合水を用いる請求項1から請求項5のいずれか1項に記載の水処理システム。 The water treatment system according to any one of claims 1 to 5, wherein a mixed water in which hydrogen peroxide is dissolved in the washing water is used as the chemical solution.
  8. 前記薬液として前記洗浄水にオゾンを溶解させた混合水を用いる請求項1から請求項5のいずれか1項に記載の水処理システム。 The water treatment system according to any one of claims 1 to 5, wherein mixed water in which ozone is dissolved in the washing water is used as the chemical solution.
PCT/JP2020/012884 2020-03-24 2020-03-24 Water treatment system WO2021192002A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN202080098624.5A CN115297949A (en) 2020-03-24 2020-03-24 Water treatment system
JP2020552417A JP6877656B1 (en) 2020-03-24 2020-03-24 Water treatment system
PCT/JP2020/012884 WO2021192002A1 (en) 2020-03-24 2020-03-24 Water treatment system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2020/012884 WO2021192002A1 (en) 2020-03-24 2020-03-24 Water treatment system

Publications (1)

Publication Number Publication Date
WO2021192002A1 true WO2021192002A1 (en) 2021-09-30

Family

ID=75961523

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2020/012884 WO2021192002A1 (en) 2020-03-24 2020-03-24 Water treatment system

Country Status (3)

Country Link
JP (1) JP6877656B1 (en)
CN (1) CN115297949A (en)
WO (1) WO2021192002A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003334414A (en) * 2002-05-20 2003-11-25 Hosokawa Micron Corp Filter cleaning method
JP2010023866A (en) * 2008-07-17 2010-02-04 Iwai Kikai Kogyo Co Ltd Liquid sending method for liquid left in pipeline
WO2016031331A1 (en) * 2014-08-29 2016-03-03 三菱電機株式会社 Filtration membrane cleaning method and cleaning device, and water treatment system
JP2016172218A (en) * 2015-03-17 2016-09-29 株式会社クボタ Cleaning method of separation membrane of membrane separation apparatus, and cleaning system

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3408699B2 (en) * 1996-09-05 2003-05-19 株式会社クボタ Sewage treatment equipment using immersion type membrane separation equipment
JP2004057883A (en) * 2002-07-26 2004-02-26 Mitsubishi Heavy Ind Ltd Water cleaning method using external pressure type hollow fiber membrane module and apparatus therefor
JP2004188252A (en) * 2002-12-09 2004-07-08 Sanki Eng Co Ltd Membrane filtration apparatus and its operating method
JP2005087887A (en) * 2003-09-17 2005-04-07 Fuji Electric Systems Co Ltd Membrane washing method
JP2007296500A (en) * 2006-05-08 2007-11-15 Toray Ind Inc Membrane separation apparatus and membrane filtration method
JP4192205B2 (en) * 2007-04-09 2008-12-10 メタウォーター株式会社 Membrane cleaning method and membrane cleaning apparatus
JP2009082858A (en) * 2007-10-01 2009-04-23 Kurita Water Ind Ltd Cleaning method for filter membrane
CN102616954B (en) * 2011-07-28 2013-09-11 广州市市政工程设计研究院 Integrated water purification and supply method and system
KR101573569B1 (en) * 2012-12-27 2015-12-01 롯데케미칼 주식회사 Cleaning system of separation membrane and method using the same
CN103566764B (en) * 2013-11-22 2016-01-13 厦门理工学院 A kind of recovery effluent cycle regeneration device and method of road cleaning sweeper

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003334414A (en) * 2002-05-20 2003-11-25 Hosokawa Micron Corp Filter cleaning method
JP2010023866A (en) * 2008-07-17 2010-02-04 Iwai Kikai Kogyo Co Ltd Liquid sending method for liquid left in pipeline
WO2016031331A1 (en) * 2014-08-29 2016-03-03 三菱電機株式会社 Filtration membrane cleaning method and cleaning device, and water treatment system
JP2016172218A (en) * 2015-03-17 2016-09-29 株式会社クボタ Cleaning method of separation membrane of membrane separation apparatus, and cleaning system

Also Published As

Publication number Publication date
JPWO2021192002A1 (en) 2021-09-30
JP6877656B1 (en) 2021-05-26
CN115297949A (en) 2022-11-04

Similar Documents

Publication Publication Date Title
JP5933854B1 (en) Method and apparatus for cleaning filtration membrane of water to be treated, and water treatment system
JP5821838B2 (en) Hollow fiber membrane filtration device and method for cleaning hollow fiber membrane module
JP2001079366A (en) Method for washing membrane
JP5467793B2 (en) Operation method of submerged membrane separator
WO2015156242A1 (en) Water treatment method and water treatment apparatus each using membrane
CN106103349A (en) Method for treating water
CN111032578B (en) Water treatment membrane cleaning device and cleaning method
WO2013111826A1 (en) Desalination method and desalination device
JP2015155076A (en) Separation film module cleaning method
JP2012086182A (en) Water treatment method and water treatment device
JP6877656B1 (en) Water treatment system
JP5126153B2 (en) Membrane separation activated sludge treatment equipment
WO2011108589A1 (en) Method for washing porous membrane module, and fresh water generator
JP2009082858A (en) Cleaning method for filter membrane
JP5423184B2 (en) Filtration membrane module cleaning method and cleaning apparatus
JP2006081979A (en) Membrane washing method
WO2022157926A1 (en) Cleaning device for filtration membrane, water treatment device, and cleaning method for filtration membrane
JP7325694B1 (en) Filtration membrane cleaning device
JP7120496B1 (en) Filtration membrane cleaning device, water treatment device, and filtration membrane cleaning method
JP2015123436A (en) Water treatment method
JP7284545B1 (en) MEMBRANE FILTRATION DEVICE AND WATER PURIFICATION SYSTEM USING THE SAME
JP2012239936A (en) Water treatment method and apparatus
JP2010253358A (en) Membrane separation type activated sludge treatment apparatus
US20230271140A1 (en) Method for washing hollow fiber membrane module
WO2019202775A1 (en) Method for cleaning filtration module, and filter device

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2020552417

Country of ref document: JP

Kind code of ref document: A

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20927338

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20927338

Country of ref document: EP

Kind code of ref document: A1