JP2011230038A - Water treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water treatment apparatus with more excellent treatment performances than water treatment apparatuses using only carbon powder.SOLUTION: The water treatment apparatus for separating waste of processed water in solid and liquid includes a mixing means for mixing the processed water, ion exchange resin powder, and activated carbon powder, and a solid-liquid separation means for performing solid-liquid separation of the processed water containing the ion exchange resin powder and the activated carbon powder.

Description

  The present invention relates to a water treatment apparatus for removing soluble and insoluble waste contained in liquids such as river water, lake water, ground water, human waste, sewage, and wastewater.

  As a conventional water treatment apparatus, a system for solid-liquid separation after mixing powdered activated carbon in water to be treated is generally known. This method mixes and stirs powdered activated carbon in the water to be treated, adsorbs organic matter to the powdered activated carbon, and then separates the powdered activated carbon into solid and liquid. 1 and the like.

Japanese Patent No. 2525701

  In the water treatment apparatus using the powdered activated carbon as described above, the following problems are associated with the removal of organic substances, particularly trihalomethane generation ability (THMFP). First, since activated carbon cannot basically remove ionic substances, it cannot remove bromide ions in water to be treated, which are greatly involved in the production of trihalomethanes. Secondly, powdered activated carbon is consumed in a relatively large amount, but is disposable, and when used continuously for a long period of time, it is necessary to reduce the amount of use as much as possible in order to reduce running costs.

  Then, an object of this invention is to provide the water treatment apparatus which can solve at least any one of the said subjects.

  The present invention is a water treatment apparatus for solid-liquid separation of waste water to be treated, which comprises mixing means for mixing the water to be treated, powder ion exchange resin and powdered activated carbon, the powder ion exchange resin and the powder. Solid-liquid separation means for performing solid-liquid separation of water to be treated containing activated carbon.

  Moreover, the said water treatment apparatus WHEREIN: It is preferable that the said powder ion exchange resin contains an anion exchange resin or an amphoteric ion exchange resin.

  Further, in the water treatment apparatus, the solid-liquid separation means includes a membrane filtration device, a coagulation filtration device, a coagulation membrane filtration device, a coagulation sediment filtration device, a coagulation sedimentation membrane filtration device, a pressure flotation filtration device, and a pressure flotation membrane filtration. Preferably any of the devices.

  Moreover, the said water treatment apparatus WHEREIN: It is preferable that the average particle diameter of the said powder ion exchange resin is the range of 30 micrometers-70 micrometers.

  According to the present invention, at least one of these problems can be solved.

It is a schematic diagram which shows an example of a structure of the water treatment apparatus which concerns on this embodiment. It is a schematic diagram which shows another example of a structure of the water treatment apparatus which concerns on this embodiment. It is a schematic diagram which shows another example of a structure of the water treatment apparatus which concerns on this embodiment. It is a schematic diagram which shows another example of a structure of the water treatment apparatus which concerns on this embodiment. It is a schematic diagram which shows another example of a structure of the water treatment apparatus which concerns on this embodiment.

  Embodiments of the present invention will be described below. This embodiment is an example for carrying out the present invention, and the present invention is not limited to this embodiment.

  FIG. 1 is a schematic diagram illustrating an example of a configuration of a water treatment device according to the present embodiment. As shown in FIG. 1, the water treatment apparatus 1 includes a mixing tank 10 as a mixing means, a water line 12 to be treated, an ion exchange resin / activated carbon addition line 14, a mixed liquid discharge line 16, and a solid-liquid separation means. As a membrane filtration device 18 and a treated water discharge line 20. A stirring device 22 is provided in the mixing tank 10. The stirrer 22 is not limited as long as the water to be treated, the powdered ion exchange resin, and the powdered activated carbon are sufficiently contacted. For example, stirring using a stirring blade, line stirring, pump circulation, or the like may be used.

  The ion exchange resin / activated carbon addition line 14 is not necessarily required, and an operator may directly add the powder ion exchange resin and the powdered activated carbon used in the present embodiment to the mixing tank 10. In addition, although mentioned later for details, since a powder ion exchange resin and powder activated carbon may be made into a slurry form and added to the mixing tank 10, it is preferable to install the ion exchange resin and activated carbon addition line 14 in that case.

  A treated water line 12 is connected to the raw water inlet (not shown) of the mixing tank 10, and an ion exchange resin / active carbon addition line is connected to the ion exchange resin / active carbon inlet (not shown) of the mixing tank 10. 14 is connected, and a mixed liquid discharge line 16 is connected to a mixed liquid discharge port (not shown) of the mixing tank 10. Further, the mixed liquid discharge line 16 from the mixing tank 10 is connected to an inlet (not shown) of the membrane filtration device 18. A treated water discharge line 20 is connected to a discharge port (not shown) of the membrane filtration device 18.

  Below, the processing method by the water treatment apparatus 1 of this embodiment is demonstrated.

  The treated water is introduced into the mixing tank 10 from the treated water line 12. Further, powder ion exchange resin and powdered activated carbon are also charged into the mixing tank 10. As described above, in the case of slurry, it is preferable to add to the mixing tank 10 through the ion exchange resin / activated carbon addition line 14. And the to-be-processed water, powder ion exchange resin, and powdered activated carbon are stirred and contacted in the mixing tank 10, and the waste material of to-be-processed water is adsorbed by the powder ion exchange resin. By this powder ion exchange resin, unnecessary substances in water, particularly organic substances, are adsorbed efficiently in a short time. Thereafter, the water to be treated is supplied from the mixed liquid discharge line 16 to the membrane filtration device 18, and the filtrate water solid-liquid separated by the membrane filtration device 18 is discharged from the treated water discharge line 20 as treated water.

  The present inventors have paid attention to the removal of organic substances in the treated water, particularly trihalomethane generating ability (THMFP), and as a result of examining and examining the method of removing THMFP from the treated water using various adsorbents, It was found that THMFP in the water to be treated can be efficiently adsorbed in the shortest time when the ion exchange resin is used in combination. That is, since the powder ion exchange resin can adsorb and fix bromide ions, which are constituents of trihalomethane, by ion exchange, THMFP can be removed more efficiently than when powdered activated carbon is used alone. Become. Normally, when the treatment water contains 0.1 mg / L or more of bromide ions, even if the organic substances (TOC) that are THM precursors are removed with activated carbon etc., they are completely removed and clean THM precursors and bromide ions And hypochlorous acid combine to form brominated THM (bromodichloromethane, dibromochloromethane, bromoform) relatively easily. Naturally, by reducing the TOC as a THM precursor, these brominated THMs are also reduced, but the THM removal rate tends to be lower than the TOC removal rate. Conversely, if most of the THMFP is chloroform, the TOC removal rate and the THMFP reduction rate tend to be similar.

  Furthermore, since the amount of powder ion-exchange resin added can be reduced due to its adsorption mechanism, the total amount added can be reduced even when used in combination with powdered activated carbon, compared with the case where powdered activated carbon is used alone. The device itself can also be made smaller, and a large amount of waste such as powdered activated carbon can be dispensed with.

  Powdered ion exchange resin adsorbs organic substances by charge or ion exchange, so when used in combination with powdered activated carbon, it can also remove hydrophilic substances and low molecular weight substances that are difficult to obtain with powdered activated carbon alone. Odorous substances and organic substances derived from humin can be removed. In addition, since the powder ion exchange resin has polarity, it is easily neutralized by charge neutralization with a small amount of aggregating agent, so that it can be easily separated by solid-liquid separation means such as membrane filtration or sand filtration. it can.

  In this embodiment, the mixing tank 10 is exemplified as the mixing means. However, if the contact time between the powder ion exchange resin and the powdered activated carbon and the water to be treated can be ensured, the mixing tank 10 does not need to be a tank and has a predetermined distance. (Line) etc. may be sufficient. The form of the mixing tank 10 is not particularly limited, such as a square tank or a round tank.

  The mixing tank 10 may be applied with the same design as the mixing tank used in general agglomeration equipment, and the residence time of the water to be treated in the mixing tank 10 is sufficient if it is 1 minute or longer. The longer the residence time of the water to be treated, the more the waste can be treated with certainty, so it is preferable to set it within a range of about 5 minutes to several tens of minutes.

  The membrane filtration device 18 used in the present embodiment is constituted by membrane modules such as a flat membrane type, an internal pressure type hollow fiber, an external pressure type hollow fiber, a monolith type, and a spiral type. Microfiltration membrane (MF), ultrafiltration membrane (UF), etc. are applied to the filtration membrane used in the membrane module, and various organic and inorganic materials, various pore sizes, and fractional products can be selected. is there.

  Although the to-be-processed water used as the process target of this embodiment is not restrict | limited in particular, For example, river water, lake water, ground water, human waste, sewage, industrial wastewater etc. are mentioned. Further, in the present invention, there are no limitations on the substances to be adsorbed on the powder ion exchange resin and powdered activated carbon, but any soluble and insoluble substances are included, and various inorganic substances, organic compounds, ions, suspended substances, etc. Is mentioned.

  There are two methods for injecting the powder ion exchange resin into the mixing tank 10: adding the powder as it is, and injecting it as a slurry liquid. Here, the powder ion exchange resin is obtained by pulverizing generally produced ion exchange resin granules (for example, a particle diameter of 500 to 700 μm or more). When the slurry of the powder ion exchange resin is poured into the mixing tank 10, the concentration of the slurry is not limited, but for example, a slurry of 30 to 50% by volume is preferable in terms of workability. The addition amount of the powder ion exchange resin may be appropriately set depending on the quality of the water to be treated, but is generally in the range of 0.01 mg / L to 5 mg / L.

  The type of the powder ion exchange resin is not particularly limited, but is a powder anion exchange resin having an anion exchange group or an anion exchange group in that organic substances can be effectively removed from wastes in the water to be treated. A powder amphoteric ion exchange resin is preferred. This is because, in particular, naturally-occurring organic substances in the water to be treated are negatively charged or dissociated as anions, so that the powder anion exchange resin or powder zwitterion having the above anion exchange group It can be efficiently adsorbed by the exchange resin.

  As the particle size of the powder ion exchange resin increases, the specific surface area decreases, and the ability to remove unnecessary substances (particularly organic substances) in the water to be treated may decrease. Further, the smaller the particle size, the worse the sedimentation property, and the subsequent solid-liquid separation tends to be difficult. In the present embodiment, the average particle size of the powder ion exchange resin having a good balance between the specific surface area and the solid-liquid separation is preferably in the range of 30 μm to 70 μm.

  The powdered activated carbon is not particularly limited as long as it is powdered activated carbon generally used for water treatment.

  There are two methods for injecting the powdered activated carbon into the mixing tank 10: adding the powder as it is and injecting it as a slurry liquid. When injecting the powdered activated carbon slurry into the mixing tank 10, the concentration of the slurry is not limited, but for example, a slurry of 5 to 50% by volume is preferable in terms of workability. The addition amount of the powdered activated carbon may be appropriately set depending on the quality of the water to be treated, but is generally in the range of 0.1 mg / L to 50 mg / L.

  When injecting a slurry of powder ion exchange resin and powdered activated carbon into the mixing tank 10, separate slurry may be injected into the mixing tank 10 from separate pipes, or a mixed slurry of powder ion exchange resin and powdered activated carbon may be preliminarily prepared. It may be prepared and added to the mixing tank 10 from the ion exchange resin / activated carbon addition line 14. However, when using a mixed slurry, the addition rates of powdered activated carbon and powder ion exchange resin cannot be changed separately according to the quality of the water to be treated.

  As described above, the type of waste in the for-treatment water treated by the water treatment apparatus 1 of the present embodiment is not particularly limited, but the for-treatment water targeted for removal of organic substances having a molecular weight of 1000 or less. In this case, the water treatment apparatus of the present embodiment functions effectively.

  The residence time of the water to be treated in the mixing tank 10 may be appropriately set depending on the quality of the treated water, and is not particularly limited, but is approximately several minutes to several tens of minutes.

  FIG. 2 is a schematic diagram illustrating another example of the configuration of the water treatment apparatus of the present embodiment. In the water treatment device 2 shown in FIG. 2, the same reference numerals are given to the same configurations as those of the water treatment device 1 shown in FIG. 1, and the description thereof is omitted. As shown in FIG. 2, the water treatment device 2 includes a coagulation filtration device as a solid-liquid separation unit. The coagulation filtration apparatus includes a coagulation tank 24 and a filter 26. A stirring device 28 is provided in the aggregation tank 24. The stirring device 28 may be any device as long as the water to be treated and the powder ion exchange resin are sufficiently contacted. For example, stirring using a stirring blade, stirring by a pump, or the like may be used.

  In the water treatment apparatus 2, the mixed liquid discharge line 16 a from the mixing tank 10 is connected to a mixed liquid supply port (not shown) of the coagulation tank 24, and is aggregated to the coagulant supply port (not shown) of the coagulation tank 24. An agent addition line 30 is connected, and a pH adjuster addition line 32 is connected to a pH adjuster supply port (not shown) of the coagulation tank 24. The mixed liquid discharge line 16b from the aggregation tank 24 is connected to a supply port (not shown) of the filter 26. A treated water discharge line 20 is connected to a discharge port (not shown) of the filter 26.

  Below, the processing method by the water treatment apparatus 2 of this embodiment is demonstrated.

  The treated water is introduced into the mixing tank 10 from the treated water line 12. Powder ion exchange resin is also charged into the mixing tank 10. Then, the water to be treated and the powder ion exchange resin are agitated and contacted in the mixing tank 10, and the waste of the water to be treated is adsorbed to the powder ion exchange resin. Thereafter, the water to be treated is supplied from the mixed liquid discharge line 16a to the aggregation tank 24. Further, an arbitrary amount of the flocculant is supplied from the flocculant addition line 30 to the flocculent tank 24. Since the powder ion exchange resin has polarity, it is easily neutralized by charge neutralization even with a small amount of aggregating agent and aggregates easily and strongly, so that subsequent solid-liquid separation is facilitated.

  Moreover, a pH adjuster is supplied to the aggregation tank 24 from the pH adjuster addition line 32 as needed, and pH adjustment is performed. In the agglomeration tank 24, the powder ion exchange resin and the suspended matter in the water to be treated are micro-flocculated, then supplied from the mixed liquid discharge line 16b to the filter 26, and solid-liquid separated by the filter 26. The The filtered water subjected to solid-liquid separation is discharged from the treated water discharge line 20 as treated water.

  The coagulation tank 24 is a tank for coagulating the powder ion exchange resin and the like by diffusing the coagulant into the water to be treated containing the powder ion exchange resin, and has the same design as the coagulation tank used for general coagulation precipitation equipment. It is preferable to select a facility in which the residence time of the water to be treated in the coagulation tank 24 is about 1 to 5 minutes and no short circuit flow occurs. Here, in this embodiment, although the coagulation tank 24 is used, if the contact time of to-be-processed water and the coagulant | flocculant can be ensured, it is not necessary to be a tank, A pipe | tube (line) etc. which have predetermined distance It may be.

  The method for adding the flocculant is not particularly limited, but a method capable of quantitative control injection is preferable, and for example, a natural flow method, an ink jet method, a pump pressure method, and the like are common. The flocculant is not particularly limited, and examples thereof include polyaluminum chloride (PAC), sulfate band, iron chloride and the like. Further, if necessary, pH adjusting agents such as acids and alkalis, aggregation aids such as activated silicic acid and acrylamide can be used.

  The filter 26 is used for solid-liquid separation of water to be treated containing (flocculated) powder ion exchange resin. For example, a sand filter or the like is used. The sand filter is preferably water filtration equipment or rapid filtration equipment used in general industries. Both gravity and pressure systems can be used, and it is preferable to use them according to local conditions, filtration speed, and sand layer. .

  The filtration rate of the sand filter is determined according to the quality of the water to be treated, but is generally in the range of 120 m / day to 360 m / day. The height and composition of the sand layer are determined by the filtration rate and the quality of the water to be treated, but the total filter layer height is generally in the range of 60 cm to 80 cm, and the sand layer is silica sand having a particle size of 0.45 mm to 0.6 mm. Is preferably used. In the case of multi-layer filtration, it is preferable to use anthracite, garnet, or the like. The anthracite preferably has a particle size in the range of 0.8 mm to 1.2 mm, and the garnet preferably has a particle size in the range of 0.3 mm to 0.4 mm.

  FIG. 3 is a schematic diagram illustrating another example of the configuration of the water treatment device according to the present embodiment. The water treatment device 3 shown in FIG. 3 includes an agglomerated membrane filtration device as solid-liquid separation means. The aggregation membrane filtration device includes an aggregation tank 24 and a membrane filtration device 18. Even with such a configuration, it is possible to efficiently remove unnecessary materials in the water to be treated.

  FIG. 4 is a schematic diagram illustrating another example of the configuration of the water treatment apparatus according to the present embodiment. In the water treatment device 4 shown in FIG. 4, the same components as those in the water treatment device 2 shown in FIG. The water treatment device 4 shown in FIG. 4 includes a coagulation sedimentation filtration device as solid-liquid separation means. The coagulation sedimentation filtration apparatus includes a coagulation tank 24, a flock formation tank 34 that communicates with the aggregation tank 24, a sedimentation tank 36 that is provided in the subsequent stage of the flock formation tank 34, and a filter 26. And between the mixing tank 10 and the coagulation tank 24, between the flock formation tank 34 and the settling tank 36, and between the settling tank 36 and the filter 26 are connected by the mixed liquid discharge lines 16a, 16b, and 16c. Yes.

  Below, the processing method by the water treatment apparatus 4 of this embodiment is demonstrated.

  The treated water is introduced into the mixing tank 10 from the treated water line 12. Powder ion exchange resin is also charged into the mixing tank 10. Then, the water to be treated and the powder ion exchange resin are agitated and contacted in the mixing tank 10, and the waste of the water to be treated is adsorbed to the powder ion exchange resin. Thereafter, the water to be treated is supplied from the mixed liquid discharge line 16a to the aggregation tank 24. Further, an arbitrary amount of the flocculant is supplied from the flocculant addition line 30 to the flocculent tank 24. Moreover, a pH adjuster is supplied to the aggregation tank 24 from the pH adjuster addition line 32 as needed, and pH adjustment is performed. In the agglomeration tank 24, the powder ion exchange resin, suspended substances in the water to be treated, and the like are microflocked and sent to the flock formation tank 34. In the flock formation tank 34, flocs are coarsened, and the water to be treated that has been flocked is sent to the settling basin 36 from the mixed liquid discharge line 16b. The settled solid matter is discharged out of the system from the sludge line 40 below the settling basin 36, and the supernatant water at the top of the settling basin is supplied to the filter 26 from the mixed liquid discharge line 16c. The solid-liquid separation is performed by 26. The separated filtered water is discharged from the treated water discharge line 20 as treated water.

  Since the true specific gravity of the powder ion exchange resin is about 1.1, the flocs have good sedimentation properties. However, when a large amount of suspended matter is contained in the water to be treated, the sedimentation basin 36 after flocculation as in this embodiment. After the flocs are settled and separated, solid-liquid separation is performed by the subsequent filter 26 or the like, so that both removal of organic substances and the solid-liquid separation treatment can be achieved satisfactorily.

  The floc-forming tank 34 can be applied with the same design as the floc-forming tank used in general coagulation sedimentation equipment, and preferably a tank that has a residence time of about 20 to 40 minutes and does not cause short-circuit flow or stagnation. Is done. The flock forming tank 34 is provided with a stirring device 38. The stirrer 38 installed in the floc forming tank 34 is preferably a slow stirrer in order to coarsen the floc.

  The sedimentation basin 36 is not particularly limited as long as flocs can be separated by sedimentation, and examples thereof include a lateral flow sedimentation basin and an inclined plate sedimentation basin. Further, depending on the amount of suspended water to be treated, a high-speed coagulating sedimentation basin in which the flock formation tank 34 and the sedimentation basin 36 are combined can be employed.

  FIG. 5 is a schematic diagram illustrating another example of the configuration of the water treatment device according to the present embodiment. The water treatment device 5 shown in FIG. 5 includes a coagulation sedimentation membrane filtration device as a solid-liquid separation means. The coagulation sedimentation membrane filtration apparatus includes a coagulation tank 24, a flock formation tank 34, a sedimentation basin 36, and a membrane filtration apparatus 18. Even with such a configuration, it is possible to efficiently remove unnecessary materials in the water to be treated.

  As other solid-liquid separation means, a generally known pressurized flotation filtration device, a pressurized flotation membrane filtration device, or the like can be employed. The pressurization flotation device is not particularly limited as long as the floc can be floated and separated, but, for example, a high-speed pressurization flotation tank as known in Japanese Patent Application Laid-Open No. 2010-005519 can also be used. .

  The water treatment apparatus shown in FIGS. 1 to 5 is an example of an apparatus that can be used in the present invention, and the present invention is not limited to the above-illustrated apparatus at all, as long as the gist of the present invention is not changed. Various types of water treatment devices can be employed.

  As described above, according to the water treatment apparatus of the present embodiment, the removal rate of soluble and insoluble organic substances, particularly THMFP, contained in the for-treatment water can be improved.

  Hereinafter, although an example and a reference example are given and the present invention is explained more concretely in detail, the present invention is not limited to the following examples.

  In the examples, the industrial water was treated under the following conditions using the water treatment apparatus of FIG.

<Powder ion exchange resin>
For the powder ion exchange resin of the examples, an ion exchange resin having an average particle size of 0.59 mm to 0.70 mm (IRA402BL (OH) -HG, manufactured by Rohm and Haas) was crushed to an average particle size of about 40 μm. It was. Diamond Hope 6 MW (manufactured by Mitsubishi Chemical Calgon) was used as the powdered activated carbon in the examples. And 1 mg / L of powder ion exchange resin and 5 mg / L of powdered activated carbon were added to the mixing tank.

<Mixing tank>
Mixing tank capacity: 40L
Stirring speed: 120rpm
Processed water flow rate: 206L / h
Residence time of treated water: 11 min
<Coagulation tank>
Coagulation tank capacity: 40L
Stirring speed: 120rpm
Processing flow rate: 206L / h
Retention time of treated water: 11 min
Flocculant: Polyaluminum chloride (PAC)
<Membrane filtration device>
Filtration membrane: FE membrane from FE10 (Daisen Membrane Systems) Filtration flow rate: 206 L / h

  In Comparative Example 1, the test was performed under the same conditions as in Example except that only powdered activated carbon was added and the addition amount was 5 mg / L.

  In Comparative Example 2, the test was performed under the same conditions as in Example except that only powdered activated carbon was added and the addition amount was 20 mg / L.

  Comparative Example 3 was tested under the same conditions as in Example except that only powder ion exchange resin was added and the amount added was 1 mg / L.

  As test results of Examples and Comparative Examples 1 to 3, the quality of treated water of Examples and Comparative Examples 1 to 3 is summarized in Table 1.

  As can be seen from Table 1, when Examples and Comparative Examples 1 to 3 were compared, there was almost no difference in turbidity. Regarding the removal rate of chromaticity, Example and Comparative Example 3 to which the powder ion exchange resin was added improved more than Comparative Examples 1 and 2 to which the powder ion exchange resin was not added. Even if only the powder ion exchange resin was added as in Comparative Example 3, the removal effect of THMFP was seen to some extent, but by using the powder ion exchange resin and powdered activated carbon in combination as in the example, the remarkable effect of THMFP was obtained. There was a significant decrease. When powder ion exchange resin and powdered activated carbon are used in combination, bromide ions, which constitute trihalomethane, can be removed by powder ion exchange resin after efficiently adsorbing TOC components that are easily adsorbed. There was a tendency that can be effectively removed.

  1-5 Water treatment device, 10 Mixing tank, 12 Water to be treated line, 14 Ion exchange resin / activated carbon addition line, 16a, 16b, 16c Mixed liquid discharge line, 18 Membrane filtration device, 20 Treated water discharge line, 22, 28 , 38 Stirrer, 24 Coagulation tank, 26 Filter, 30 Coagulant addition line, 32 pH adjuster addition line, 34 Flock formation tank, 36 Sedimentation basin, 40 Waste mud line.

Claims (4)

  A water treatment apparatus for solid-liquid separation of waste water to be treated, the mixing means for mixing the water to be treated, a powder ion exchange resin, and powdered activated carbon, and a target containing the powder ion exchange resin and the powdered activated carbon. And a solid-liquid separation means for performing solid-liquid separation of the treated water.   The water treatment apparatus according to claim 1, wherein the powder ion exchange resin includes an anion exchange resin or an amphoteric ion exchange resin.   The solid-liquid separation means is any one of a membrane filtration device, an aggregation filtration device, an aggregation membrane filtration device, an aggregation precipitation filtration device, an aggregation precipitation membrane filtration device, a pressurized flotation filtration device, and a pressurized flotation membrane filtration device. The water treatment apparatus according to claim 1 or 2, characterized in that   The water treatment apparatus according to any one of claims 1 to 3, wherein an average particle diameter of the powder ion exchange resin is in a range of 30 µm to 70 µm.

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