JP6816292B2 - Water treatment method and water treatment equipment - Google Patents

Description

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

In recent years, there have been increasing opportunities for opaque membranes to be used in water and sewage treatment, factory wastewater treatment, and the like. However, it is known that high molecular weight organic substances contained in the water to be treated cause membrane blockage in the turbid film. Here, the opaque membrane refers to a microfiltration membrane (MF membrane) and an ultrafiltration membrane (UF membrane). Further, examples of the high molecular weight organic substance include biological metabolites contained in treated water for biological treatment, anionic polymers added in agglomeration solid-liquid separation treatment, and the like.

Therefore, the polymer organic matter is reduced by the aggregation treatment using an anion polymer in the pretreatment, the turbidity step is performed by sand filtration instead of the membrane, or the polymer organic matter is prepared by using a catalyst and an oxidizing agent in the pretreatment. Measures such as oxidative decomposition (see Patent Document 1) have been taken.

However, if the anionic polymer added in the coagulation treatment is excessively added, it causes further membrane blockage in the opaque membrane in the subsequent stage, so it is difficult to manage the operation in wastewater treatment or natural water treatment in factories where the water quality fluctuates. .. Further, when sand filtration is adopted, the quality of the treated water is inferior to that of the membrane treatment. When performing oxidative decomposition, the process and equipment become complicated.

Japanese Patent No. 6128964

An object of the present invention is to remove deterioration of treated water quality in a treatment using a turbid membrane of water to be treated containing a high molecular weight organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less. It is an object of the present invention to provide a water treatment method and a water treatment apparatus capable of suppressing clogging of a turbid film.

The present invention includes a decontamination step of treating water to be treated containing a high molecular weight organic substance having a weight average molecular weight in the range of 100,000 or more and 3,000,000 or less using a decontamination film . The material is at least one of polyvinylidene fluoride, polyvinyl chloride, and polyether sulfone, the high molecular weight organic substance is an anionic polymer flocculant, and the weight average molecular weight of the water to be treated is 30. A water treatment method in which a cation polymer in the range of 000 or more and 3,000,000 or less is added.

In the water treatment method, it is preferable that the cationic polymer has a structure of any one of polyamine-based, methacrylate-based, and polydiallyldimethylammonium chloride-based.

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 weight average molecular weight of the cationic polymer is preferably 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 agglomeration solid-liquid separation treatment using an anionic polymer flocculant and a biological treatment in the first stage of the turbidity step.

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

It is preferable that the water treatment method further includes a reverse osmosis membrane treatment step in which the treated water in the turbidity step is treated with a reverse osmosis membrane.

Further, the present invention comprises a decontamination device for treating water to be treated containing a polymer organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less using a decontamination film, and the water to be treated. A chemical injection means for adding a cationic polymer having a weight average molecular weight of 30,000 or more and a weight average molecular weight of 3,000,000 or less is provided , and the material of the turbid film is polyvinylidene fluoride, polyvinyl chloride, and poly. is at least one of polyethersulfone, the polymer organic material, Ru der anionic polymeric flocculant is a water treatment device.

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

In the water treatment device, it is preferable to provide a coagulation solid-liquid separation treatment device using an anionic polymer flocculant and a pretreatment device which is at least one of the biological treatment devices in front of the turbidity device.

In the water treatment device, it is preferable to provide a coagulation solid-liquid separation treatment device using an acrylamide-based anionic polymer flocculant in front of the deturbation device.

It is preferable that the water treatment apparatus further includes a reverse osmosis membrane treatment apparatus that treats the treated water of the decontamination apparatus with a reverse osmosis membrane.

According to the present invention, in a treatment using a turbid film of water to be treated containing a polymer organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less, the turbid film while suppressing deterioration of the treated water quality. Can suppress the blockage of.

It is a schematic block diagram which shows an example of the water treatment apparatus which concerns on embodiment of this invention. It is a schematic block diagram which shows another 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 cation polymer used and the time required for filtration (minutes) in an Example and a comparative example. It is a graph which shows the relationship between the weight average molecular weight and the membrane transmittance (%) of the cation polymer used in an Example and a comparative example.

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

An outline of an example of a water treatment apparatus according to an embodiment of the present invention is shown in FIG. 1, and its configuration will be described. The water treatment device 1 includes a decontamination device 12 for treating with a decontamination film. The water treatment device 1 may include a water tank 10 to be treated to store water to be treated, if necessary.

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

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

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

The water to be treated to which the cation polymer is added is sent to the decontamination device 12 through the water supply pipe 16 to be treated, and is deturbidized in the decontamination device 12 using a decontamination film (deturbation step). .. The treated water that has undergone the turbidization step is discharged through the treated water pipe 18.

In the treatment using a turbid film of the water to be treated containing a high molecular weight organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less, the present inventors have weight-averaged the weight of the water to be treated of the turbid film. 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 the clogging of the turbid membrane while suppressing the deterioration of the treated water quality. In addition, it is possible to deturbate the water to be treated containing the above-mentioned polymer organic matter by a simple process or apparatus. It is considered that by adding the cationic polymer to the water to be treated of the turbid membrane, the polymer organic substance is captured by the cationic polymer, and the membrane clogging due to the polymer organic substance is suppressed. Further, by adding the above-mentioned cation polymer to the water to be treated of the turbid membrane, the rate of increase of the differential pressure in the turbid membrane is suppressed.

If the weight average molecular weight of the added cation polymer is too large, it becomes a load for membrane filtration by the turbid membrane, which causes an increase in the operating pressure of the turbid membrane. If the weight average molecular weight is too small, the cation polymer permeates the turbidizing membrane, causing deterioration of the treated water quality, which becomes a load on the reverse osmosis membrane when a reverse osmosis membrane device is provided in the subsequent stage. The pore size of the opaque membrane varies depending on the type and shape of the membrane, but the smaller one has a molecular weight cut-off of about 30,000 Da. Further, if the weight average molecular weight is 3,000,000 or less, it is considered that the turbid membrane filtration is not excessively burdened. 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 cation polymer to be added is in the range of 30,000 or more and 3,000,000 or less, preferably 200,000 or more and 3,000,000 or less, and is 200,000 or more and 200,000 or more. More preferably, it is in the range of 600,000 or less. When the weight average molecular weight of the cation polymer exceeds 3,000,000, the load on the membrane becomes slightly large, and the reduction amount of the filtration time may be small. When the weight average molecular weight of the cationic polymer is less than 30,000, the membrane permeability may be large, and particularly when it is less than 200,000, the membrane permeability may be large.

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

Examples of the polyamine-based cationic polymer include dimethylamine / epichlorohydrin / ammonia condensate, 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。The dimethylamine / epichlorohydrin / ammonia condensate is, for example, the following formula (1).

(1)
The structure represented by and the following formula (2)

(2)
It is a polymer containing the structure represented by. In the above polymer, the ratio of the structure represented by the formula (2) to the structure represented by the formula (1) is the 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。The dimethylamine / epichlorohydrin / ethylenediamine condensate has, for example, a structure represented by the formula (1) and the following formula (3).

(3)
It is a polymer containing the structure represented by. In the above polymer, the ratio of the structure represented by the formula (3) to the structure represented by the formula (1) is the 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. a and b represent the molar ratio of monomas (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-based cationic polymer is, for example, the following formula (5).

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

The amount of the cation polymer added 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 substance. If the amount of the cation polymer added is less than 1% by weight with respect to the weight of the polymer organic substance, the effect of suppressing clogging of the turbid film is less likely to be exhibited, and if it exceeds 100% by weight, the quality of treated water deteriorates and the cation polymer deteriorates. It may itself block the membrane.

The temperature of the water to be treated when the cation polymer is added is not particularly limited, but is, for example, in the range of 5 ° C to 40 ° C.

The water to be treated may be any water containing a high molecular weight organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less, and is not particularly limited. The high molecular weight organic substance contained in the water to be treated is an organic substance detected as a biopolymer in an LC-OCD analyzer (DOC-LABOR, model 8), and its characteristic is that the weight average molecular weight is 100. It is 3,000 or more, and the upper limit is not particularly set, but is, for example, 30,000,000 or less. Examples of the polymer organic matter contained in the water to be treated include biotransformers contained in the treated water for biological treatment, anionic polymers such as anionic polymer flocculants added in the coagulation solid-liquid separation treatment, and the like. ..

The content of the high molecular weight organic substance contained in the water to be treated is, for example, in the range of 0.1 mg / L to 10 mg / L, and 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 form are effective.

The sterilization membrane used in the sterilization 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 diameter of the microfiltration membrane is 0.1 μm or more and 10 μm or less. Expressed 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 opaque film may be a flat film type or a hollow fiber type.

This technique is effective when the material of the dehumidifying film is one that forms hydrogen bonds and easily chemically bonds with high molecular weight organic substances. For example, polyvinylidene fluoride, polyvinyl chloride, and polyether sulfone are effective. And so on.

In the water treatment method and the water treatment apparatus according to the present embodiment, a reverse osmosis membrane treatment apparatus for treating the treated water of the decontamination apparatus 12 with a reverse osmosis membrane is further provided, and the treated water in the decontamination step is treated 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, the coagulation solid-liquid separation treatment apparatus using an anion polymer and the pretreatment apparatus which is at least one of the biological treatment apparatus are provided in front of the sterilization apparatus 12. In the first stage of the turbidity step, it is preferable to perform at least one pretreatment of agglomeration solid-liquid separation treatment using an anion polymer and a biological treatment.

FIG. 2 shows a schematic configuration of another example of the water treatment apparatus according to the present embodiment. The water treatment device 3 further includes a decontamination device 12 for treating with a decontamination membrane and a reverse osmosis membrane treatment device 24 for treating the treated water of the decontamination device 12 with a reverse osmosis membrane. In addition, the water treatment device 3 includes a coagulation solid-liquid separation treatment device using an anion polymer and a pretreatment device 22 which is at least one of the biological treatment devices in front of the turbidity removal device 12. The water treatment device 3 may include a water tank 10 to be treated to store the water to be treated, if necessary.

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

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

The water to be treated to which the cation polymer is added is sent to the decontamination device 12 through the water supply pipe 16 to be treated, and is deturbidized in the decontamination device 12 using a decontamination film (deturbation step). .. The treated water that has undergone the turbidization step is sent to the reverse osmosis membrane treatment device 24 through the treated water pipe 18, and is treated with the reverse osmosis membrane using the reverse osmosis membrane in the reverse osmosis membrane treatment device 24 (reverse osmosis membrane). Processing process). The permeated water is discharged through the permeated water pipe 26, and the concentrated water is discharged through the concentrated water pipe 28.

Even when a reverse osmosis membrane treatment device for treating the treated water of the decontamination device with a reverse osmosis membrane is further provided after the water treatment device 3 as in the water treatment device 3 of FIG. 2, the weight average molecular weight is 30. By using a cationic polymer in the range of 000 or more and 3,000,000 or less, the permeation of the turbid film of the cationic polymer is suppressed, and the load on the reverse osmosis membrane is reduced.

As in the case of the water treatment device 3 of FIG. 2, a pretreatment device which is at least one of a coagulation solid-liquid separation treatment device using an anion polymer and a biological treatment device is provided in front of the sterilization device 12. 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 to a biological metabolite contained in treated water for biological treatment or in agglomeration solid-liquid separation treatment. It is possible to suppress the clogging of the turbid film by a high molecular weight organic substance such as an anionic polymer such as an anionic polymer flocculant.

The reverse osmosis membrane treatment may be any treatment using a reverse osmosis membrane, and is not particularly limited.

The coagulation solid-liquid separation treatment may be a treatment including a coagulation treatment using a coagulant and a solid-liquid separation treatment, and is not particularly limited, and examples thereof include a coagulation sedimentation treatment and a coagulation pressure flotation treatment. .. Examples of the anion polymer used in the coagulation solid-liquid separation treatment include an acrylamide-based anionic polymer flocculant. The agglomerated solid-liquid separation treated water contains this anionic polymer as a high molecular weight organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less. In particular, when the agglomerated solid-liquid separation treated water contains an acrylamide-based anion polymer as a polymer organic substance having a weight average molecular weight in the range of 100,000 or more and 3,000,000 or less, the water treatment according to the present embodiment. The method and water treatment equipment are preferably applied.

The biological treatment may be any treatment using organisms such as microorganisms, and is not particularly limited. The biotreated water contains anionic polymers such as biotransformers as high molecular weight organic substances having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

<Examples 1 to 5>
50 L of water to be treated containing a high molecular weight organic substance was prepared and passed through a turbid film. As the polymer organic substance, 0.2 mg / L of an anion polymer (acrylamide-based anionic polymer flocculant) having a weight average molecular weight of 10,000,000 was added. As the turbidity membrane, an ultrafiltration membrane (hollow fiber type) manufactured by Ritsusho Co., Ltd., material: polyvinyl chloride, molecular weight cut-off: 50,000 Da, pore diameter: 0.01 μm is used, and the membrane area is 1 m ^2. The module was made.

The water flow was carried out by adding 2 mg / L of each of the cationic polymers shown in Table 1 to the water to be treated, and the time required to filter all the water to be treated was measured. In addition, the membrane transmittance (%) of the polymer was measured by measuring the polymer concentration in the turbid membrane filtered water (treated water).

Polymer A (Example 1) is a polyamine-based cationic polymer, a dimethylamine / epichlorohydrin / ethylenediamine condensate (weight average molecular weight of 30,000), and polymer B (Example 2) is a polyamine-based polymer. Dimethylamine / epichlorohydrin / ethylenediamine condensate (weight average molecular weight 70,000), which is a cationic polymer of the above, 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 the polymer D (Example 4) is a polydialyldimethylammonium chloride-based cationic polymer (weight average molecular weight 600,000), and the polymer E (implementation). Example 5) is a methacrylate-based cationic polymer (weight average molecular weight 3,000,000).

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

<Comparative Examples 1 to 3>
In Comparative Example 1, the water to be treated was treated without adding a cation polymer. The polymer F (Comparative Example 2) is polyaluminum chloride (weight average molecular weight 2,500), and the 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. 3 and 4. FIG. 3 shows the relationship between the weight average molecular weight of the cation polymer used 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 cation polymer used and the membrane transmittance (%) in Examples and Comparative Examples.

As shown in Table 1 and FIGS. 3 and 4, cationic polymers having a weight average molecular weight in the range of 30,000 to 3,000,000 showed the most effect of suppressing obstruction of the opaque membrane. A polymer F having a weight average molecular weight of 30,000 or less (Comparative Example 2) is not preferable because the cation polymer easily permeates the turbid membrane, although the filtration time is shortened. In the polymer G having a weight average molecular weight of 3,000,000 or more (Comparative Example 3), the filtration time becomes long, which is not preferable. The polymer C of Example 3 had an excellent balance between the time required for filtration and the membrane transmittance.

As described above, in the examples, in the treatment using the turbid film of the water to be treated containing the polymer organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less, the deterioration of the treated water quality is suppressed. , It was possible to suppress the blockage of the turbid film.

1,3 Water treatment equipment, 10 Water tank to be treated, 12 Decontamination equipment, 14 Water treatment pipe, 16 Water treatment water supply pipe, 18 Treated water pipe, 20 Cationic polymer addition pipe, 22 Pretreatment equipment, 24 Reverse osmosis membrane Treatment equipment, 26 permeated water pipes, 28 concentrated water pipes.

Claims (14)

A decontamination step of treating water to be treated containing a high molecular weight organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less using a decontamination film is included.
The material of the turbid film is at least one of polyvinylidene fluoride, polyvinyl chloride, and polyether sulfone.
The polymer organic substance is an anionic polymer flocculant and is
A water treatment method comprising 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. The water treatment method according to claim 1.
A water treatment method, wherein the cationic polymer is a cationic polymer having a structure of any one of polyamine-based, methacrylate-based, and polydiallyldimethylammonium chloride-based. The water treatment method according to claim 1 or 2.
A 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 weight average molecular weight of the cationic polymer is in the range 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 comprising at least one pretreatment of a coagulation solid-liquid separation treatment using an anionic polymer flocculant and a biological treatment in the first stage of the turbidity step. The water treatment method according to claims 1 to 4.
A water treatment method characterized by performing a coagulation solid-liquid separation treatment using an acrylamide-based anionic polymer flocculant in the first stage of the turbidity step. The water treatment method according to any one of claims 1 to 6 .
A water treatment method further comprising a reverse osmosis membrane treatment step of treating the treated water in the turbidity step with a reverse osmosis membrane. A decontamination device that treats water to be treated containing a high molecular weight organic substance having a weight average molecular weight in the range of 100,000 or more and 30,000,000 or less using a decontamination film.
A medicinal 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.
Equipped with a,
The material of the turbid film is at least one of polyvinylidene fluoride, polyvinyl chloride, and polyether sulfone.
The polymer organic material, the water treatment apparatus according to claim der Rukoto anionic polymer flocculant. The water treatment apparatus according to claim 8 .
A water treatment apparatus, wherein the cationic polymer is a cationic polymer having a structure of any one of polyamine-based, methacrylate-based, and polydiallyldimethylammonium chloride-based. The water treatment apparatus according to claim 8 or 9 .
A water treatment apparatus, wherein the cationic polymer is a dimethylamine / epichlorohydrin / ethylenediamine condensate or a dimethylamine / epichlorohydrin / ammonia condensate. The water treatment apparatus according to any one of claims 8 to 10 .
A water treatment apparatus characterized in that the weight average molecular weight of the cationic polymer is in the range of 200,000 or more and 3,000,000 or less. The water treatment apparatus according to any one of claims 8 to 11 .
A water treatment device characterized in that a coagulation solid-liquid separation treatment device using an anionic polymer flocculant and a pretreatment device which is at least one of biological treatment devices are provided in front of the turbidity device. The water treatment apparatus according to claims 8 to 11 .
A water treatment apparatus characterized in that a coagulation solid-liquid separation treatment apparatus using an acrylamide-based anionic polymer flocculant is provided in front of the deturbation apparatus. The water treatment apparatus according to any one of claims 8 to 13 .
A water treatment apparatus further comprising a reverse osmosis membrane treatment apparatus for treating the treated water of the turbidity apparatus with a reverse osmosis membrane.

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