JPWO2019044312A1 - Water treatment method and water treatment apparatus - Google Patents

Abstract

In the treatment using a turbidity-treating film containing polymer organic matter having a weight average molecular weight of 100,000 or more and 30,000,000 or less, the deterioration of the treated water is suppressed and the blocking of the turbidity film is suppressed. Provided are a water treatment method and a water treatment apparatus that can be used. It includes a turbidity treatment step for treating water to be treated containing a polymer organic material having a weight average molecular weight in the range of 100,000 to 30,000,000 using a turbidity membrane, and the weight average molecular weight is 30 in the water to be treated. A water treatment method in which a cationic polymer in the range of 3,000 to 3,000,000 is added.

Description

  The present invention relates to a water treatment method and a water treatment apparatus.

  In recent years, opportunities for using turbidity membranes are increasing in water and sewage treatment and factory wastewater treatment. However, it is known that high molecular organic substances contained in the water to be treated cause membrane clogging in the turbidity membrane. Here, the turbidity membrane means a microfiltration membrane (MF membrane) and an ultrafiltration membrane (UF membrane). Examples of the polymer organic material include biological metabolites contained in treated water for biological treatment and anionic polymers added in the aggregation solid-liquid separation treatment.

  For this reason, the polymer organic matter is reduced by agglomeration treatment using an anionic polymer in the pretreatment, the turbidity process is performed using sand filtration instead of the membrane, or the polymer organic matter is removed using a catalyst and an oxidizing agent in the pretreatment. Measures such as oxidative decomposition (see Patent Document 1) are taken.

  However, if the anionic polymer added in the coagulation treatment is excessively added, it will cause further membrane clogging in the subsequent turbidity membrane, so that it is difficult to manage the operation in the wastewater treatment or natural water treatment of the factory where the water quality varies. . Moreover, when sand filtration is employ | adopted, the quality of the treated water is inferior compared with a membrane process. When oxidative decomposition is performed, the process and apparatus become complicated.

Japanese Patent No. 6128964

  The object of the present invention is to remove water while suppressing deterioration of treated water in a treatment using a turbidity-treated membrane containing a polymer organic material having a weight average molecular weight in the range of 100,000 to 30,000,000. An object of the present invention is to provide a water treatment method and a water treatment apparatus capable of suppressing clogging of a turbid film.

  The present invention includes a turbidity treatment step for treating water to be treated containing a polymer organic material having a weight average molecular weight in the range of 100,000 to 30,000,000 using a turbidity membrane, In this water treatment method, a cationic polymer having a weight average molecular weight of 30,000 or more and 3,000,000 or less is added.

  In the water treatment method, the cationic polymer is preferably a cationic polymer having a structure selected from polyamine-based, methacrylate-based, and polydiallyldimethylammonium chloride-based structures.

  In the water treatment method, the cationic polymer is preferably a dimethylamine / epichlorohydrin / ethylenediamine condensate or a dimethylamine / epichlorohydrin / ammonia condensate.

  In the water treatment method, the cationic polymer preferably has a weight average molecular weight in the range of 200,000 or more and 3,000,000 or less.

  In the water treatment method, it is preferable to perform at least one pretreatment of an aggregation solid-liquid separation treatment using an anionic polymer and a biological treatment before the turbidity removing step.

  In the preceding stage of the turbidity step in the water treatment method, it is preferable to perform an aggregation solid-liquid separation treatment using an acrylamide-based anionic polymer.

  In the water treatment method, it is preferable that the material of the turbidity removal film is at least one of polyvinylidene fluoride, polyvinyl chloride, and polyethersulfone.

  The water treatment method preferably further includes a reverse osmosis membrane treatment step of treating the treated water in the turbidity removal step with a reverse osmosis membrane.

  In addition, the present invention provides a turbidity treatment apparatus for treating water to be treated containing a polymer organic material having a weight average molecular weight of 100,000 to 30,000,000 using a turbidity membrane, and the water to be treated. And a chemical injection means for adding a cationic polymer having a weight average molecular weight in the range of 30,000 or more and 3,000,000 or less.

  In the water treatment apparatus, the cationic polymer is preferably a cationic polymer having a structure of any one of polyamine-based, methacrylate-based, and polydiallyldimethylammonium chloride-based.

  In the water treatment apparatus, the cationic polymer is preferably a dimethylamine / epichlorohydrin / ethylenediamine condensate or a dimethylamine / epichlorohydrin / ammonia condensate.

  In the water treatment apparatus, the cationic polymer preferably has a weight average molecular weight in the range of 200,000 or more and 3,000,000 or less.

  In the water treatment apparatus, it is preferable that a pretreatment apparatus which is at least one of an agglomerated solid-liquid separation treatment apparatus using an anionic polymer and a biological treatment apparatus is provided in the previous stage of the turbidity removal apparatus.

  In the water treatment apparatus, it is preferable that a flocculation solid-liquid separation treatment apparatus using an acrylamide-based anion polymer is provided upstream of the turbidity removal apparatus.

  In the water treatment apparatus, it is preferable that the material of the turbidity removal film is at least one of polyvinylidene fluoride, polyvinyl chloride, and polyethersulfone.

  The water treatment device preferably further includes a reverse osmosis membrane treatment device for treating the treated water of the turbidity removal device with a reverse osmosis membrane.

  According to the present invention, in a treatment using a turbidity-treating film containing a polymer organic material having a weight average molecular weight of 100,000 or more and 30,000,000 or less, a turbidity-treating film while suppressing deterioration of the treated water quality. Can be prevented.

It is a schematic structure figure showing an example of the water treatment equipment concerning the embodiment of the present invention. It is a schematic block diagram which shows the other example of the water treatment apparatus which concerns on embodiment of this invention. It is a graph which shows the relationship between the weight average molecular weight of the used cation polymer in Example and a comparative example, and the time required for filtration (minute). It is a graph which shows the relationship between the weight average molecular weight of the used cationic polymer and membrane permeability | transmittance (%) in an Example and a comparative example.

  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.

  An example of a water treatment apparatus according to an embodiment of the present invention is schematically shown in FIG. The water treatment device 1 includes a turbidity removal device 12 that performs treatment using a turbidity removal membrane. The water treatment apparatus 1 may include a water tank 10 to be treated for storing the water to be treated as necessary.

  In the water treatment apparatus 1 of FIG. 1, a treated water pipe 14 is connected to the inlet of the treated water tank 10. The outlet of the water tank 10 to be treated and the inlet of the turbidizer 12 are connected by a water supply pipe 16 to be treated. A treated water pipe 18 is connected to the turbidizer 12. A cation polymer addition pipe 20 is connected to the water tank 10 as chemical injection means for adding the cation polymer to the water to be treated.

  The operation of the water treatment method and the water treatment apparatus 1 according to this embodiment will be described.

  To-be-treated water containing a high molecular weight organic material having a weight average molecular weight in the range of 100,000 to 30,000,000 is stored in the to-be-treated water tank 10 through the to-be-treated water pipe 14 as necessary. In the water tank 10 to be treated, a cationic polymer having a weight average molecular weight in the range of 30,000 to 3,000,000 is added to the water to be treated through the cationic polymer addition pipe 20 (cation polymer addition step). The cationic polymer may be added in the treated water pipe 14 or may be added in the treated water supply pipe 16.

  The treated water to which the cationic polymer has been added is sent to the turbidity device 12 through the treated water supply pipe 16 and is turbidized using the turbidity membrane in the turbidity device 12 (turbidity removing step). . The treated water subjected to the turbidity process is discharged through the treated water pipe 18.

  In the treatment using a turbidity-treating film containing a polymer organic material having a weight-average molecular weight in the range of 100,000 to 30,000,000, the weight-average molecular weight of the turbidity-treated water is a weight average. It has been found that by adding a cationic polymer having a molecular weight in the range of 30,000 or more and 3,000,000 or less, it is possible to suppress clogging of the turbidity membrane while suppressing deterioration of treated water quality. Moreover, the turbidity treatment of the water to be treated containing the above-mentioned polymer organic substance can be performed with a simple process or apparatus. By adding the cationic polymer to the water to be treated of the turbidity removal membrane, it is considered that the macromolecular organic matter is trapped by the cationic polymer, whereby the membrane occlusion by the polymeric organic matter is suppressed. Moreover, the rate of increase in the differential pressure in the turbidity membrane is suppressed by adding the cationic polymer to the water to be treated of the turbidity membrane.

  If the weight average molecular weight of the cationic polymer to be added is too large, it becomes a load of membrane filtration by the turbidity membrane, and increases the operating pressure of the turbidity membrane. If the weight average molecular weight is too small, the cationic polymer permeates through the turbidity membrane and causes deterioration of the quality of the treated water. When a reverse osmosis membrane device is provided in the subsequent stage, it becomes a load on the reverse osmosis membrane. The pore size of the turbidity membrane varies depending on the type and shape of the membrane, but is small and has a molecular weight cut-off of about 30,000 Da. Moreover, if it is a weight average molecular weight 3,000,000 or less, it will be considered that it will not become an excessive burden of turbidity membrane filtration. Therefore, it is considered that the weight average molecular weight of the added cationic polymer is preferably in the range of 30,000 or more and 3,000,000 or less.

  The weight average molecular weight of the cationic polymer to be added is in the range of 30,000 to 3,000,000, preferably in the range of 200,000 to 3,000,000, preferably 200,000 and A range of 600,000 or less is more preferable. When the weight average molecular weight of the cationic polymer exceeds 3,000,000, the load on the membrane is slightly increased, and the reduction amount of the filtration time may be reduced. When the weight average molecular weight of the cationic polymer is less than 30,000, the membrane permeability may increase, and when it is less than 200,000, the membrane permeability may increase.

  The cationic polymer may be any polymer having a cation having a weight average molecular weight of 30,000 or more and 3,000,000 or less, and is not particularly limited, but polyamine-based, methacrylate-based, and polydiallyldimethylammonium. A cationic polymer having any one of the chloride structures is preferred.

  Examples of the polyamine-based cationic polymer include a dimethylamine / epichlorohydrin / ammonia condensate, a dimethylamine / epichlorohydrin / ethylenediamine condensate, and the like.

（１）
で表される構造、および、下記式（２）

（２）
で表される構造を含むポリマである。上記ポリマでは、式（２）で表される構造と式（１）で表される構造の割合が、モル比（式（２）で表される構造：式（１）で表される構造）で例えば０．０１：９．９９〜７：３であればよい。Examples of the dimethylamine / epichlorohydrin / ammonia condensate include the following formula (1):

(1)
And a structure represented by the following formula (2)

(2)
It is a polymer containing the structure represented by these. In the polymer, the ratio of the structure represented by the formula (2) to the structure represented by the formula (1) is a molar ratio (structure represented by the formula (2): structure represented by the formula (1)). For example, it may be 0.01: 9.99 to 7: 3.

（３）
で表される構造を含むポリマである。上記ポリマでは、式（３）で表される構造と式（１）で表される構造の割合が、モル比（式（３）で表される構造：式（１）で表される構造）で例えば０．０１：９．９９〜７：３であればよい。Examples of the dimethylamine / epichlorohydrin / ethylenediamine condensate include the structure represented by the formula (1) and the following formula (3):

(3)
It is a polymer containing the structure represented by these. In the polymer, the ratio of the structure represented by the formula (3) to the structure represented by the formula (1) is a molar ratio (structure represented by the formula (3): structure represented by the formula (1)). For example, it may be 0.01: 9.99 to 7: 3.

（４）
で表される構造を含むポリマである。ａ，ｂはモノマのモル比（ａ：ｂ＝０．０１：９．９９〜９．９９：０．０１）を表す。The methacrylate-based cationic polymer is, for example, the following formula (4)

(4)
It is a polymer containing the structure represented by these. a and b represent the molar ratio of monomers (a: b = 0.01: 9.99 to 9.99: 0.01).

（５）
で表される構造を含むポリマである。ｎは繰り返し単位を表す。The polydiallyldimethylammonium chloride cationic polymer is, for example, the following formula (5):

(5)
It is a polymer containing the structure represented by these. n represents a repeating unit.

  The addition amount of the cationic polymer is, for example, in the range of 1 to 100% by weight and preferably in the range of 2 to 10% by weight with respect to the weight of the polymer organic material. When the addition amount of the cationic polymer is less than 1% by weight with respect to the weight of the high molecular organic substance, it becomes difficult to exert the effect of suppressing the clogging of the turbidity membrane. It may occlude the membrane itself.

  Although the temperature of the to-be-processed water at the time of adding a cationic polymer does not have a restriction | limiting in particular, For example, it is the range of 5 to 40 degreeC.

  The water to be treated may be water containing a high molecular weight organic material having a weight average molecular weight in the range of 100,000 to 30,000,000, and is not particularly limited. The polymer organic substance contained in the water to be treated is an organic substance detected as a biopolymer in an LC-OCD analyzer (manufactured by DOC-LABOR, model 8), and has a weight average molecular weight of 100. The upper limit is not particularly defined, but is, for example, 30,000,000 or less. Examples of the polymer organic substance contained in the water to be treated include a biological metabolite contained in the treated water for biological treatment, an anionic polymer such as an anionic polymer flocculant added in the aggregation solid-liquid separation treatment, and the like. .

  The content of the high molecular organic substance contained in the water to be treated is, for example, in the range of 0.1 mg / L to 10 mg / L, particularly in the case of the range of 0.2 mg / L to 1.0 mg / L. The water treatment method and the water treatment apparatus according to the embodiment are effective.

  The turbidity membrane used in the turbidity treatment is a microfiltration membrane (MF membrane) or an ultrafiltration membrane (UF membrane). The nominal pore size of the ultrafiltration membrane is 0.01 μm or more and less than 0.1 μm, and the pore size of the microfiltration membrane is 0.1 μm or more and 10 μm or less. In terms of molecular weight cut-off, the molecular weight cut-off of the ultrafiltration membrane is 1,000 or more and less than 1,000,000.

  The turbidity removal membrane may be a flat membrane type or a hollow fiber type.

  The technology of the present invention is effective when the material of the turbidity film is one that forms a hydrogen bond and is likely to be chemically bonded to a high molecular organic substance. For example, polyvinylidene fluoride, polyvinyl chloride, polyethersulfone, etc. Etc.

  In the water treatment method and the water treatment apparatus according to the present embodiment, the water treatment method and the water treatment apparatus further include a reverse osmosis membrane treatment device that treats the treated water of the turbidity removal device 12 with a reverse osmosis membrane, and treats the treated water in the turbidity process with the reverse osmosis membrane. It is preferable to further include a reverse osmosis membrane treatment step.

  In the water treatment method and the water treatment apparatus according to the present embodiment, a pretreatment apparatus that is at least one of an agglomerated solid-liquid separation treatment apparatus using an anionic polymer and a biological treatment apparatus is provided in the previous stage of the turbidity removal apparatus 12. In the previous stage of the turbidity removing step, it is preferable to perform at least one pretreatment of an agglomerated solid-liquid separation treatment using an anionic polymer and a biological treatment.

  The schematic structure of the other example of the water treatment apparatus which concerns on this embodiment is shown in FIG. The water treatment device 3 further includes a turbidity treatment device 12 for treatment using a turbidity removal membrane, and a reverse osmosis membrane treatment device 24 for treating the treated water of the turbidity reduction device 12 with a reverse osmosis membrane. Further, the water treatment device 3 includes a pretreatment device 22 that is at least one of an agglomerated solid-liquid separation treatment device using an anionic polymer and a biological treatment device in a stage preceding the turbidity removal device 12. The water treatment apparatus 3 may include a water tank 10 to be treated for storing the water to be treated as necessary.

  In the water treatment device 3 of FIG. 2, the outlet of the pretreatment device 22 and the inlet of the treated water tank 10 are connected by the treated water pipe 14. The outlet of the water tank 10 to be treated and the inlet of the turbidizer 12 are connected by a water supply pipe 16 to be treated. The outlet of the turbidizer 12 and the inlet of the reverse osmosis membrane treatment device 24 are connected by a treated water pipe 18. A permeate outlet 26 of the reverse osmosis membrane treatment device 24 is connected to a permeate outlet 26, and a concentrate outlet 28 is connected to the concentrate outlet. A cation polymer addition pipe 20 is connected to the water tank 10 as chemical injection means for adding the cation polymer to the water to be treated.

  In the water treatment device 3, water to be treated containing polymer organic matter having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less discharged from the pretreatment device 22 is necessary through the treatment water pipe 14. Is stored in the water tank 10 to be treated. In the water tank 10 to be treated, a cationic polymer having a weight average molecular weight in the range of 30,000 to 3,000,000 is added to the water to be treated through the cationic polymer addition pipe 20 (cation polymer addition step). The cationic polymer may be added in the treated water pipe 14 or may be added in the treated water supply pipe 16.

  The treated water to which the cationic polymer has been added is sent to the turbidity device 12 through the treated water supply pipe 16 and is turbidized using the turbidity membrane in the turbidity device 12 (turbidity removing step). . The treated water subjected to the turbidity process is sent to the reverse osmosis membrane treatment device 24 through the treated water pipe 18, and the reverse osmosis membrane treatment device 24 performs reverse osmosis membrane treatment using the reverse osmosis membrane (reverse osmosis membrane). Processing step). The permeated water is discharged through the permeated water pipe 26, and the concentrated water is discharged through the concentrated water pipe 28.

  Even in the case of further including a reverse osmosis membrane treatment device that treats the treated water of the turbidity treatment device with a reverse osmosis membrane in the subsequent stage of the turbidity removal device, as in the water treatment device 3 of FIG. By using a cationic polymer in the range of 000 or more and 3,000,000 or less, permeation of the cationic polymer through the turbidity-imparting membrane is suppressed, and the load on the reverse osmosis membrane is reduced.

  Like the water treatment device 3 in FIG. 2, the turbidity removal device 12 is provided with a pretreatment device that is at least one of an agglomerated solid-liquid separation treatment device using an anionic polymer and a biological treatment device in the previous stage. However, by using a cationic polymer having a weight average molecular weight in the range of 30,000 or more and 3,000,000 or less, for example, it is added in biological metabolites contained in the treated water of biological treatment, or in aggregation solid-liquid separation treatment It is possible to suppress clogging of the turbidity film by a polymer organic material such as an anionic polymer such as an anionic polymer flocculant.

  The reverse osmosis membrane treatment is not particularly limited as long as it is a treatment using a reverse osmosis membrane.

  The aggregation solid-liquid separation treatment is not particularly limited as long as it is a treatment including an aggregation treatment using a flocculant and a solid-liquid separation treatment. Examples of the aggregation solid-liquid separation treatment include an aggregation precipitation treatment and an aggregation pressure floating treatment. . Examples of the anionic polymer used in the flocculation solid-liquid separation treatment include an acrylamide type anionic polymer flocculant. The agglomerated solid-liquid separation treated water contains this anionic polymer as a high molecular weight organic material having a weight average molecular weight in the range of 100,000 to 30,000,000. In particular, when the flocculated solid-liquid separation treated water contains an acrylamide-based anionic polymer as a polymer organic material having a weight average molecular weight in the range of 100,000 to 30,000,000, the water treatment according to the present embodiment. The method and the water treatment apparatus are preferably applied.

  The biological treatment is not particularly limited as long as it uses a living organism such as a microorganism. Biologically treated water contains anionic polymers such as biological metabolites as high-molecular organic substances having a weight average molecular weight in the range of 100,000 to 30,000,000.

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

<Examples 1-5>
50 L of water to be treated containing a polymer organic material was prepared and passed through a turbidity membrane. As the high molecular organic substance, 0.2 mg / L of an anionic polymer (acrylamide-type anionic polymer flocculant) having a weight average molecular weight of 10,000,000 was added. As the turbidity removal membrane, an ultrafiltration membrane (hollow fiber type) having a material: polyvinyl chloride, a molecular weight cut off: 50,000 Da, and a pore size: 0.01 μm is used as the turbidity removal membrane, and the membrane area is 1 m ^2. A module was produced.

  Water flow was performed by adding 2 mg / L of the cationic polymer shown in Table 1 to the water to be treated, and measuring the time required to filter all the water to be treated. Further, the membrane permeability (%) of the polymer was measured by measuring the polymer concentration in the turbidity membrane filtered water (treated water).

  Polymer A (Example 1) is a polyamine-based cationic polymer, dimethylamine / epichlorohydrin / ethylenediamine condensate (weight average molecular weight 30,000), and polymer B (Example 2) is a polyamine-based polymer. Dimethylamine / epichlorohydrin / ethylenediamine condensate (weight average molecular weight 70,000), and polymer C (Example 3) is a polyamine-based cationic polymer, dimethylamine / epichloro. It is a hydrin-ammonia condensate (weight average molecular weight 200,000), and polymer D (Example 4) is a polydiallyldimethylammonium chloride based cationic polymer (weight average molecular weight 600,000) and polymer E (implemented). Example 5) is a methacrylate-based cationic polymer (weight average molecular weight 3,000). , It is a 000).

  The polymer concentration in the turbidity membrane filtered water (treated water) was measured using a combustion method TOC analyzer (manufactured by Shimadzu Corporation, TOC-V).

<Comparative Examples 1-3>
In Comparative Example 1, treatment was performed without adding a cationic polymer to the water to be treated. Polymer F (Comparative Example 2) is polyaluminum chloride (weight average molecular weight 2,500), and Polymer G (Comparative Example 3) is an acrylate-based cationic polymer (weight average molecular weight 10,000,000).

  The results are shown in Table 1 and FIGS. FIG. 3 shows the relationship between the weight average molecular weight of the used cationic polymer and the time required for filtration (minutes) in Examples and Comparative Examples. FIG. 4 shows the relationship between the weight average molecular weight of the used cationic polymer and the membrane permeability (%) in Examples and Comparative Examples.

  As shown in Table 1 and FIGS. 3 and 4, the cationic polymer having a weight average molecular weight in the range of 30,000 to 3,000,000 showed the most effective occlusion suppression effect on the turbidity membrane. Polymer F having a weight average molecular weight of 30,000 or less (Comparative Example 2) is not preferable because the time required for filtration is shortened but the cationic polymer easily permeates the turbidity membrane. In the polymer G (Comparative Example 3) having a weight average molecular weight of 3,000,000 or more, the time required for filtration is undesirably long. The polymer C of Example 3 was excellent in the balance between filtration time and membrane permeability.

  As described above, in the examples, in the treatment using the turbidity-treating film containing the polymer organic material having the weight average molecular weight in the range of 100,000 to 30,000,000, the deterioration of the treated water quality is suppressed. The obstruction of the turbidity membrane could be suppressed.

  1,3 water treatment apparatus, 10 treated water tank, 12 turbidity removal apparatus, 14 treated water pipe, 16 treated water supply pipe, 18 treated water pipe, 20 cation polymer added pipe, 22 pretreatment apparatus, 24 reverse osmosis membrane Treatment equipment, 26 permeate piping, 28 concentrated water piping.

Claims (16)

Including a turbidity step of treating water to be treated containing a polymer organic material having a weight average molecular weight of 100,000 or more and 30,000,000 or less using a turbidity membrane;
A water treatment method comprising adding a cationic polymer having a weight average molecular weight of 30,000 to 3,000,000 to the water to be treated. The water treatment method according to claim 1,
The water treatment method, wherein the cationic polymer is a cationic polymer having a structure selected from polyamine-based, methacrylate-based, and polydiallyldimethylammonium chloride-based structures. The water treatment method according to claim 1 or 2,
The water treatment method, wherein the cationic polymer is a dimethylamine / epichlorohydrin / ethylenediamine condensate or a dimethylamine / epichlorohydrin / ammonia condensate. The water treatment method according to any one of claims 1 to 3,
A water treatment method, wherein the cationic polymer has a weight average molecular weight of 200,000 or more and 3,000,000 or less. The water treatment method according to any one of claims 1 to 4,
A water treatment method characterized by performing at least one pretreatment of an agglomeration solid-liquid separation treatment using an anionic polymer and a biological treatment in a previous stage of the turbidity removing step. The water treatment method according to claim 1, wherein
A water treatment method comprising performing an agglomeration solid-liquid separation process using an acrylamide-based anionic polymer in the previous stage of the turbidity removing step. The water treatment method according to any one of claims 1 to 6,
The water treatment method is characterized in that the material of the turbidity removal membrane is at least one of polyvinylidene fluoride, polyvinyl chloride, and polyethersulfone. The water treatment method according to any one of claims 1 to 7,
A water treatment method, further comprising a reverse osmosis membrane treatment step of treating the treated water in the turbidity removal step with a reverse osmosis membrane. A turbidity treatment apparatus for treating water to be treated containing a polymer organic material having a weight average molecular weight of 100,000 or more and 30,000,000 or less using a turbidity membrane;
A chemical injection means for adding a cationic polymer having a weight average molecular weight of 30,000 or more and 3,000,000 or less to the water to be treated;
A water treatment apparatus comprising: The water treatment device according to claim 9,
The water treatment apparatus, wherein the cationic polymer is a cationic polymer having a structure selected from a polyamine system, a methacrylate system, and a polydiallyldimethylammonium chloride system. The water treatment device according to claim 9 or 10,
A water treatment apparatus, wherein the cationic polymer is a dimethylamine / epichlorohydrin / ethylenediamine condensate or a dimethylamine / epichlorohydrin / ammonia condensate. The water treatment device according to any one of claims 9 to 11,
A water treatment apparatus, wherein the cationic polymer has a weight average molecular weight of 200,000 or more and 3,000,000 or less. The water treatment device according to any one of claims 9 to 12,
A water treatment device comprising a pretreatment device that is at least one of an agglomerated solid-liquid separation treatment device using an anionic polymer and a biological treatment device, in a preceding stage of the turbidity removal device. It is a water treatment apparatus of Claims 9-12,
A water treatment apparatus comprising a flocculation solid-liquid separation treatment apparatus using an acrylamide-based anion polymer in a preceding stage of the turbidity removal apparatus. The water treatment apparatus according to any one of claims 9 to 14,
The water treatment apparatus is characterized in that a material of the turbidity removal film is at least one of polyvinylidene fluoride, polyvinyl chloride, and polyethersulfone. The water treatment device according to any one of claims 9 to 15,
A water treatment device, further comprising a reverse osmosis membrane treatment device for treating the treated water of the turbidity removal device with a reverse osmosis membrane.

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