WO2022176405A1

WO2022176405A1 - Controlled release solid flocculant and water treatment device

Info

Publication number: WO2022176405A1
Application number: PCT/JP2021/048670
Authority: WO
Inventors: 楓太山口; 洋輔小中; 俊輔郡; 正彦塩井
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2021-02-19
Filing date: 2021-12-27
Publication date: 2022-08-25
Also published as: JP2022127142A

Abstract

A controlled release solid flocculant 1 which includes a solid flocculant part 10 containing a polymer flocculant, and also includes a protecting part 50 for protecting the solid flocculant part 10 from contact with water, wherein part of the surface 12 of the solid flocculant part 10 is covered by the protecting part 50. The weight-average molecular weight of the polymer flocculant is preferably at least 1,000. The flocculant surface coverage rate, which is the percentage of the surface 12 of the solid flocculant part 10 which is covered by the protecting part 50, is preferably 20-99%, inclusive.

Description

Time-release solid flocculant and water treatment equipment

This disclosure relates to a sustained-release solid flocculant and a water treatment device.

Because well water, tap water, and other domestic water may contain inorganic substances such as sand, iron rust, and iron ions, inorganic ions, and impurities such as bacteria, it is often used after being treated. For example, tap water may be contaminated with the above-mentioned impurities due to deterioration of raw water quality, deterioration of water pipes, etc., and the quality of domestic water may deteriorate. In addition, well water may be mixed with the above-mentioned impurities due to deterioration of water quality or insolubilization due to oxidation of dissolved ions, etc., and the water quality of domestic water may deteriorate.

Conventionally known methods for treating impurities in water include a water treatment method in which filtration is performed using a membrane or a sand filter medium, and a method in which a disinfectant such as a chlorine agent is used. Furthermore, as a method for removing finer particles, a water treatment method is known in which impurities are coarsened using an inorganic flocculant or a polymer flocculant. Specifically, a flocculating agent or a bactericidal agent is added to the water _W0 to be treated, such as well water, to inactivate bacteria, etc. by the bactericidal action, and flocs containing suspended solids are formed using the flocculating action of the coagulant. Then, a method of obtaining clean post-treatment water TW by removing flocs by filtration or the like is known. In order to obtain the treated water TW of stable quality, it is preferable that the change in the treatment conditions of the water treatment method is small. For this reason, it is preferable that the concentration of the coagulant in the water to be treated _W0 is small.

Generally, when a flocculant is used for flocculation treatment, the flocculant is dissolved in water, and then the flocculant solution is injected into the water to be treated using a pump. However, this method has a problem that the purification of the water to be treated is costly because the pumps used are expensive. In addition, since it is assumed that the flocculant is completely dissolved in water and then injected with a pump, the specifications are such that the flocculant dissolves quickly. Therefore, there is a problem that the coagulant cannot be dissolved in the water to be treated little by little continuously without using a pump.

As a method for inexpensively achieving sustained release for such problems, a tablet is formed by solidifying a polymer flocculant and coating the surface of the polymer flocculant with a substance that inhibits the dissolution of the polymer flocculant. We can think of a way to do this.

Patent Document 1 discloses a cleaning wastewater treatment agent for sludge-adhered wood, which is obtained by granulating a mixture of a polymer flocculant, a pH adjuster and an adsorbent, and coating the outer peripheral surface of the granules with an inorganic flocculant. ing. According to this washing wastewater treatment agent, since the outer peripheral surface is coated with an inorganic coagulant, it is said that deliquescence and oxidative decomposition can be prevented and the coagulation ability can be maintained for a long period of time.

JP 2013-78717 A

However, in general, inorganic flocculants dissolve easily when in contact with water. Therefore, based on Patent Document 1, it is difficult to produce a solid flocculant in which the polymer flocculant has sustained release properties.

The present disclosure has been made in view of such problems of the conventional technology. An object of the present disclosure is to provide a sustained-release solid flocculant in which a polymer flocculant has sustained-release properties, and a water treatment apparatus using the sustained-release solid flocculant.

In order to solve the above problems, a sustained-release solid flocculant according to an aspect of the present disclosure includes a solid flocculant part containing a polymer flocculant, and a protection part that protects the solid flocculant part from contact with water. and a portion of the surface of the solid flocculant portion is covered with the protective portion.

Also, the water treatment device according to the aspect of the present disclosure uses the sustained-release solid flocculant.

FIG. 1 is a diagram showing an example of the sustained-release solid flocculant according to the first embodiment. FIG. 2 is a diagram showing a solid flocculant part that constitutes the sustained-release solid flocculant shown in FIG. FIG. 3 is a diagram showing an example of the sustained-release solid flocculant according to the second embodiment. FIG. 4 is a diagram showing an example of a sustained-release solid flocculant according to the third embodiment. FIG. 5 is a diagram showing an example of a solid flocculant according to the reference embodiment. Drawing 6 is a key map showing an example of the water treatment equipment concerning an embodiment. 7 is a cross-sectional view of an example of a drug dissolving device that constitutes the water treatment device shown in FIG. 6. FIG. FIG. 8 is a perspective view showing an example of a drug tank that constitutes the drug dissolving device shown in FIG. FIG. 9 is a graph showing the relationship between water flow time and eluted chlorine concentration. FIG. 10 is a graph showing the relationship between water flow time and turbidity.

A sustained-release solid flocculant and a water treatment device according to embodiments will be described below with reference to the drawings. Note that the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may differ from the actual ratios.

<Slow-release solid flocculant>
[First embodiment]
A sustained-release solid flocculant according to the first embodiment will be described. FIG. 1 is a diagram showing an example of the sustained-release solid flocculant according to the first embodiment. As shown in FIG. 1, the sustained-release solid flocculant 1A (1) includes a solid flocculant portion 10A (10) containing a polymer flocculant and a protective portion that protects the solid flocculant portion 10A from contact with water. 50A (50). In the sustained-release solid flocculant 1A, part of the surface 12 of the solid flocculant portion 10A is covered with the protective portion 50A.

(Solid flocculant section)
The solid flocculant part 10A constituting the sustained-release solid flocculant 1A will be described with reference to FIG. FIG. 2 is a diagram showing a solid flocculant part 10A that constitutes the sustained-release solid flocculant 1A shown in FIG.

The solid flocculant part 10A is made of a solid substance containing a polymer flocculant. As the polymer flocculant, for example, one or more selected from the group consisting of nonionic polymer flocculants, anionic polymer flocculants, cationic polymer flocculants, and amphoteric polymer flocculants are used. It is preferable that the polymer flocculant is a cationic polymer flocculant because it facilitates flocculation of negatively charged impurities in water, such as sand and fungi, which may be mixed in with domestic water.

The polymer flocculant, for example, usually has a weight average molecular weight of 1000 or more, preferably 10,000 to 50,000,000, more preferably 100,000 to 5,000,000. When the weight-average molecular weight of the polymer flocculant is within the above range, it is preferable because it has high flocculating properties and solubility suitable for sustained release.

Examples of polymer flocculants include starch, guar gum, tamarind gum, polyethylene glycol (PEG), xanthan gum, polyamine, polydiallyldimethylammonium chloride (PDADMAC), melamine colloid, polydicyandiamide, polyacrylic acid, and polymethacrylic acid ester. , polyacrylate, sodium polyarginine, cellulose, moringa, polyalginic acid, polysilica iron (PSI), chitosan, cationic starch, cationic guar gum, polylysine, and one or more selected from the group consisting of polyglutamic acid substance is used. Among these, polydicyandiamide, polyacrylic acid, polymethacrylic acid ester, polyacrylic acid ester, and chitosan have high purification performance, and have been used as food additives, water purification plants, and wastewater treatment plants, and are safe for humans. Preferable because it is guaranteed.

The content of the polymer flocculant in the solid flocculant part 10A is usually 1 to 100% by mass, preferably 10 to 100% by mass. When the content of the polymer flocculant in the solid flocculant portion 10A is within the above range, a part of the flocculant and water can come into contact with water from the initial stage of use, and the flocculant component can be eluted, which is preferable.

The solid flocculant part 10A is a solid substance containing a polymer flocculant.

As the molded body, for example, a powder molded body obtained by molding powder of a polymer flocculant, a molded body melted and solidified once, and the like are used. Pellets, tablets and the like are usually used as powder compacts.

The average particle size D ₅₀ of the powder of the polymer flocculant used as a raw material for powder compacts such as pellets is, for example, 0.001 to 1000 μm, preferably 0.01 to 10 μm. When the average particle size _D50 of the powder of the polymer flocculant is within the above range, voids between particles in the tablet can be reduced when molded, water intrusion into the tablet is suppressed, and the dissolution life is improved. Therefore, it is preferable.

Incidentally, the polymer flocculant forming the solid flocculant portion 10A usually has a property of absorbing water and swelling when it comes into contact with water. For this reason, when the solid flocculant part 10A, which is a solid substance containing a polymer flocculant, usually contacts water such as the water to be treated _W0 , it absorbs water, expands, and dissolves in water such as the water to be treated _W0 . Or collapse. However, when the solid flocculant portion 10A dissolves or disintegrates in water such as the water to be treated _W0 , the concentration of the polymer flocculant in water usually rises sharply, and the solid flocculant portion 10A gradually increases. It is not preferable because it impairs the release property. Therefore, in the sustained-release solid coagulant 1A, a part of the surface 12 of the solid coagulant portion 10A is covered with a protective portion 50 that protects the solid coagulant portion 10A from contact with water. The protection unit 50 will be described later.

The solid flocculant part 10A shown in FIG. 2 is an example of a columnar pellet formed by molding the polymer flocculant powder. As shown in FIG. 2, the surface 12 of the solid flocculant portion 10A includes flat portions 14a (14) and 14b (14), which are circular surfaces forming the bottom and top surfaces of the cylinder, and side surfaces of the cylinder. It is composed of a curved surface portion 15 which is a cylindrical surface.

Here, S14a and 14b, which are the surface areas of the

flat portions

14a and 14b, respectively, and S15, which is the surface area of the curved surface portion 15, can be calculated by a known method. The total surface area S12 of the surface 12 constituting the solid flocculant portion 10A is the sum of S14a and 14b and S15 (S14a+S14b+S15).

Note that S14a and 14b can be easily calculated using the diameter D14 of the plane portion of the solid flocculant portion 10A and the like. Also, S15 is easily calculated using the diameter D14 of the flat portion of the solid flocculant portion 10A, the length L15 of the curved portion of the solid flocculant portion 10A, and the like.

As shown in FIG. 1, in the sustained-release solid flocculant 1A, part of the surface 12 of the solid flocculant portion 10A shown in FIG. 2 is covered with the protective portion 50A. Specifically, in the sustained-release solid flocculant 1A, the cylindrical curved surface portion 15 of the surface 12 of the solid flocculant portion 10A becomes the protective agent-coated portion 32, which is the surface coated with the protective portion 50A. ing. On the other hand, in the sustained-release solid flocculant 1A, the

circular plane portions

14a and 14b of the surface 12 of the solid flocculant portion 10A are not covered with the protective portion 50A and are exposed to the flocculant-exposed portion 22. It's becoming The protective agent-coated portion 32 and the coagulant-exposed portion 22 will be described below.

[Protective agent coated part]
In the sustained-release solid flocculant 1A shown in FIG. 1, the cylindrical curved surface portion 15 of the solid flocculant portion 10A shown in FIG.

Here, the planar portion of the protective agent-coated portion 32 is referred to as the flat portion 34 of the protective agent-coated portion, and the curved portion of the protective agent-coated portion 32 is referred to as the curved surface portion 35 of the protective agent-coated portion.

The protective agent-coated portion 32 of the sustained-release solid flocculant 1A shown in FIG. 1 is specifically the curved surface portion 35A (35) of the protective agent-coated portion. The curved surface portion 35A of the protective agent-coated portion corresponds to the tubular curved surface portion 15 of the solid flocculant portion 10A shown in FIG.

The surface area S35A of the curved surface portion 35A can be calculated by a known method. The total surface area S32 of the protective agent-covered portions 32 constituting the solid flocculant portion 10A is S35A.

The length L35 of the curved surface portion 35A of the protective agent coating portion 32 of the solid flocculant portion 10A shown in FIG. 1 is the same as the length L15 of the curved surface portion of the solid flocculant portion 10A. Further, the diameter D34 of the curved surface portion 35A of the protective agent coating portion 32 is the same as the diameter D14 of the flat surface portion of the solid flocculant portion 10A.

[Coagulant-exposed part]
In the sustained-release solid flocculant 1A shown in FIG. 1,

flat portions

14a and 14b, which are circular surfaces of the solid flocculant portion 10A shown in FIG.

Here, the planar portion of the coagulant-exposed portion 22 is referred to as a flat portion 24 of the coagulant-exposed portion, and the curved portion of the coagulant-exposed portion 22 is referred to as a curved portion 25 of the coagulant-exposed portion.

The coagulant-exposed portions 22 of the sustained-release solid coagulant 1A shown in FIG. 1 are specifically flat portions 24Aa (24) and 24Ab (24) of the coagulant-exposed portions. The flat portions 24Aa and 24Ab of the coagulant-exposed portion correspond to the circular

flat portions

14a and 14b of the solid coagulant portion 10A shown in FIG. 2, respectively.

The surface areas S24Aa and S24Ab of the planar portions 24Aa and 24Ab of the coagulant-exposed portion 22 can be calculated by a known method. The total surface area S22 of the coagulant-exposed portions 22 constituting the solid coagulant portion 10A is the sum of S24Aa and S24Ab (S24Aa+S24Ab).

The diameter D24 of the planar portions 24Aa and 24Ab of the coagulant exposed portion 22 of the solid coagulant portion 10A shown in FIG. 1 is the same as the diameter D14 of the planar portion of the solid coagulant portion 10A. The surface area S24 of the flat portion 24Aa of the coagulant exposed portion 22 is the same as the surface area S14a of the flat portion 14a. The surface area S24 of the flat portion 24Ab of the coagulant exposed portion 22 is the same as the surface area S14b of the flat portion 14b.

(protection part)
The protective part 50A that constitutes the sustained-release solid flocculant 1A will be described with reference to FIG.

The protective portion 50A is a portion that protects the solid flocculant portion 10A from contact with water. Specifically, the protective part 50A covers a part of the surface 12 of the solid flocculant part 10A, so that the solid flocculant part 10A comes into contact with water such as the water to be treated _W0 , absorbs water, and expands. and has the effect of suppressing dissolution or disintegration. Here, the action of the protection part 50A to protect the solid flocculant part 10A from contact with water means the action of suppressing water from reaching the surface 12 of the solid flocculant part 10A through the protection part 50A. The protection part 50A absorbs water, expands, dissolves or disintegrates upon contact with water such as the water to be treated _W0 , as long as it has the effect of protecting the solid flocculant part 10A from contact with water. may be In addition, it is more preferable that the protection part 50A dissolves or disintegrates in about the same time as the solid flocculant part, because it is easy to visually confirm the residual flocculant.

The protective part 50A contains a protective agent. The protective agent used is not particularly limited and has a function of protecting the solid flocculant portion 10A from contact with water when the protective portion 50A is formed.

Examples of protective agents include chlorine-containing compounds such as trichloroisocyanuric acid and dichloroisocyanuric acid, and polysaccharides such as starch, guar gum, and tamarind gum. Among them, the chlorine-containing compound sterilizes bacteria and the like contained in the water to be treated _W0 by increasing the chlorine concentration in the treated water TW obtained after the water treatment of the water to be treated _W0 , and Fe ions It is preferable because it is easy to obtain the post-treatment water TW having a low Fe concentration by oxidizing and aggregating such as. Moreover, it is preferable that the protective agent contains dichloroisocyanuric acid or trichloroisocyanuric acid as a main component.

In addition, polysaccharides are preferable because they have relatively low water absorbency, have the effect of increasing the aggregation of the polymer flocculant, and have low reactivity with the polymer flocculant and are highly safe for the human body.

When the protective agent contained in the protective part 50A contains a chlorine compound or a polysaccharide as a main component, it protects against contact with water, dissolves in about the same time as the flocculant, and simultaneously slowly releases components useful for water treatment. It is preferable because it can be done. Here, the "main component" means the largest content by mass in the protective agent contained in the protective portion 50A.

The form of the protective portion 50A is not particularly limited as long as the protective portion 50A has the effect of protecting the solid flocculant portion 10A from contact with water. As a form of the protective portion 50A, for example, a bulk body made of a protective agent, a powder compact obtained by molding powder of the protective agent, or the like is used.

The protective portion 50A shown in FIG. 1 has a cylindrical outer shape, and has an exposed surface 52 exposed to the outside and a portion that contacts the protective agent coating portion 32 of the solid flocculant portion 10A without being exposed to the outside. .

The exposed surface 52 of the protective portion 50A shown in FIG. 1 forms the side surface of the cylinder with exposed flat portions 54Aa (54) and 54Ab (54), which are annulus-shaped exposed surfaces 52 that form the top surface and the bottom surface of the cylinder. It consists of an exposed curved surface portion 55A (55) which is a cylindrical exposed surface 52. As shown in FIG.

Here, S54Aa and S54Ab, which are the surface areas of the exposed flat surface portions 54Aa and 54Ab, and S55A, which is the surface area of the exposed curved surface portion 55A, can be calculated by a known method. The total surface area S52 of the exposed surface 52 forming the protective portion 50A is the sum of S54Aa and S54Ab and S55A (S54Aa+S54Ab+S55A).

The surface area S54Aa of the exposed flat portion 54Aa and the surface area S54Ab of the exposed flat portion 54Ab are easily calculated using the diameter D54 of the exposed flat portion of the protection portion 50A and the diameter D14 of the flat portion of the solid coagulant portion. be. Further, the surface area S55A of the tubular exposed curved surface portion 55A is easily calculated using the diameter D54 of the exposed flat surface portion of the protective portion 50A and the length L55 of the exposed curved surface portion of the protective portion 50A.

(Flocculant surface coverage)
In the sustained-release solid flocculant 1A, part of the surface 12 of the solid flocculant portion 10A is covered with the protective portion 50A.

In the sustained-release solid flocculant 1A, the ratio of the surface covered with the protective part 50A to the surface 12 of the solid flocculant part 10A is called flocculant surface coverage. The flocculant surface coverage of the sustained-release solid flocculant 1A is usually 20% or more and 99% or less.

Specifically, in the sustained-release solid flocculant 1A shown in FIG. 1, the surface area S32 of the protective agent-coated portion 32 is the surface area S35A of the curved surface portion 35A. The surface area S12 of the surface 12 of the solid flocculant portion 10A is the sum of the surface area S14a of the flat portion 14a, the surface area S14b of the flat portion 14b, and the surface area S15 of the curved portion 15 (S14a+S14b+S15). Therefore, in the sustained-release solid flocculant 1A, the flocculant surface coverage ratio is (S35A)/(S14a+S14b+S15).

In addition, in the sustained-release solid flocculant 1A, the flocculant surface coverage is preferably 30% or more and 90% or less, more preferably 30% or more and 80% or less. When the surface coverage of the flocculant is within the above range, it is possible to prevent contact with water and improve the dissolution life while allowing the flocculant component necessary for water treatment to elute, which is preferable.

(Water contact specific surface area ratio)
In the sustained release solid coagulant 1A, the water contact specific surface area ratio, which is the ratio of the surface area S52 of the exposed surface 52 of the protective part 50A to the surface area S22 of the coagulant exposed part 22 of the solid coagulant part 10A, is usually 0. It is 1 or more and 100 or less.

Further, in the sustained-release solid flocculant 1A, the water contact specific surface area ratio is preferably 1 or more and 40 or less, more preferably 10 or more and 30 or less. When the water contact specific surface area ratio is within the above range, the flocculant component necessary for water treatment can be eluted while preventing water contact and improving the dissolution life, which is preferable.

(action)
The sustained-release solid flocculant 1A includes a solid flocculant portion 10A that absorbs water, swells, and dissolves or disintegrates in water such as the water _W0 to be treated when it comes into contact with water such as the water _W0 to be treated, and a solid flocculant. and a protective portion 50A that covers a portion of the surface 12 of the portion 10A. The protective portion 50A has the function of preventing water from reaching the surface 12 of the solid flocculant portion 10A through the protective portion 50A, and protects the solid flocculant portion 10A from contact with water.

Therefore, when the sustained-release solid flocculant 1A comes into contact with water such as the water to be treated _W0 , the exposed portion of the surface 12 of the solid flocculant portion 10A absorbs water, swells, and dissolves or disintegrates in water. Releases macromolecular flocculants. On the other hand, even if the portion of the surface 12 of the solid flocculant portion 10A covered with the protective portion 50A comes into contact with water, it prevents water from reaching the surface 12 of the solid flocculant portion 10A through the protective portion 50A. For this reason, when the sustained-release solid flocculant 1A is brought into contact with water such as the water to be treated _W0 , the flocculant with respect to water is lower than the case of using the flocculant composed of the solid flocculant part 10A without the protective part 50A. Sustained release of the polymer flocculant is exhibited.

In the case where the protective part 50A contacts water such as the water _W0 to be treated and releases the protective agent into the water, when the sustained-release solid flocculant 1A is brought into contact with water such as the water _W0 to be treated, , the protective agent in the protective portion 50A can be released into the water. For example, when the protective agent contained in the protective portion 50A is a chlorine-containing compound, the chlorine-containing compound can be released into water. When the chlorine-containing compound is a substance that is water-soluble and releases chloride ions, contacting the sustained-release solid flocculant 1A with water such as the water to be treated _W0 can increase the chloride ion concentration in the water. can.

If the concentration of chloride ions in the water can be increased by releasing the protective agent in the protective part 50A into the water in this way, for example, when the water to be treated _W0 is water containing Fe, iron is oxidized. Agglomeration becomes possible.

[Second embodiment]
A sustained-release solid flocculant according to the second embodiment will be described. FIG. 3 is a diagram showing an example of the sustained-release solid flocculant according to the second embodiment. As shown in FIG. 3, the sustained-release solid flocculant 1B (1) includes a solid flocculant portion 10B (10) containing a polymer flocculant and a protective portion that protects the solid flocculant portion 10B from contact with water. 50Ba (50) and 50Bb (50). Further, in the sustained-release solid flocculant 1B, part of the surface 12 of the solid flocculant portion 10B is covered with the protective portions 50Ba and 50Bb.

The sustained-release solid flocculant 1B according to the second embodiment includes protective portions 50Ba (50) and 50Bb (50) instead of the protective portion 50A of the sustained-release solid flocculant 1A according to the first embodiment. The other members are the same as the sustained-release solid flocculant 1A. For this reason, the same reference numerals are given to the same members in the sustained-release solid coagulant 1B according to the second embodiment and the sustained-release solid coagulant 1A according to the first embodiment. omission or simplification of the description of

(Solid flocculant section)
As shown in FIG. 3, in the sustained-release solid flocculant 1B, a portion of the surface 12 of the solid flocculant portion 10B shown in FIG. 2 is covered with a protective portion 50B.

The solid flocculant part 10B is the same as the solid flocculant part 10A including the shape. Therefore, description of the solid flocculant section 10B is omitted. However, the protective portions 50Ba and 50Bb that partially cover the surface 12 of the solid flocculant portion 10B are different in shape from the protective portion 50A that partially covers the surface 12 of the solid flocculant portion 10A.

Specifically, in the sustained-release solid flocculant 1B, the

circular plane portions

14a and 14b of the surface 12 of the solid flocculant portion 10B are surfaces coated with the protective portions 50Ba and 50Bb, respectively. A covering portion 32 is formed. On the other hand, in the sustained-release solid flocculant 1B, the cylindrical curved surface portion 15 of the surface 12 of the solid flocculant portion 10B becomes the flocculant exposed portion 22, which is the surface exposed without being covered with the protective portion 50B. ing. The protective agent-coated portion 32 and the coagulant-exposed portion 22 will be described below.

[Protective agent coated part]
In the sustained-release solid flocculant 1B shown in FIG. 3, the

circular plane portions

14a and 14b of the solid flocculant portion 10B shown in FIG.

The protective agent-coated portion 32 of the sustained-release solid flocculant 1B shown in FIG. 3 is specifically flat portions 34Ba (34) and 34Bb (34) of the protective agent-coated portion. The flat portions 34Ba and 34Bb of the protective agent-coated portion correspond to the circular

flat portions

14a and 14b of the solid flocculant portion 10B shown in FIG. 2, respectively.

The surface areas S34Ba and S34Bb of the flat portions 34Ba and 34Bb of the protective agent-coated portion 32 constituting the solid flocculant portion 10B can be calculated by a known method. The total surface area S32 of the protective agent-covered portions 32 constituting the solid flocculant portion 10B is the sum of S34Ba and S34Bb (S34Ba+S34Bb).

The diameter D34 of the flat portions 34Ba and 34Bb of the protective agent-coated portion 32 of the solid flocculant portion 10B shown in FIG. 3 is the same as the diameter D14 of the flat portion of the solid flocculant portion 10B. The surface area S34 of the flat portion 34Ba of the protective agent-coated portion 32 is the same as the surface area S14a of the flat portion 14a. The surface area S34 of the flat portion 34Bb of the protective agent-coated portion 32 is the same as the surface area S14b of the flat portion 14b.

[Coagulant-exposed part]
In the sustained-release solid flocculant 1B shown in FIG. 3, the tubular curved surface portion 15 of the solid flocculant portion 10B shown in FIG.

The flocculant-exposed portion 22 of the sustained-release solid flocculant 1B shown in FIG. 3 is specifically the curved surface portion 25B (25) of the flocculant-exposed portion. The curved surface portion 25B of the coagulant exposed portion corresponds to the cylindrical curved surface portion 15 of the solid coagulant portion 10B shown in FIG.

The surface area S25B of the curved surface portion 25B can be calculated by a known method. The total surface area S22 of the coagulant-exposed portions 22 constituting the solid coagulant portion 10B is S25B.

The length L25 of the curved surface portion 35B of the coagulant exposed portion 22 of the solid coagulant portion 10B shown in FIG. 3 is the same as the length L15 of the curved surface portion of the solid coagulant portion 10B. Further, the diameter D24 of the curved surface portion 25B of the coagulant exposed portion 22 is the same as the diameter D34 and the diameter D14 of the flat portion of the solid coagulant portion 10B.

(protection part)
The protective parts 50Ba and 50Bb constituting the sustained-release solid flocculant 1B will be described with reference to FIG.

The protective parts 50Ba and 50Bb are the same as the protective part 50A of the sustained-release solid coagulant 1A according to the first embodiment, except for the shape. Therefore, the shapes of the protective portions 50Ba and 50Bb will be described below.

The protective portions 50Ba and 50Bb shown in FIG. 3 each have a cylindrical outer shape, and include an exposed surface 52 exposed to the outside and a portion not exposed to the outside but in contact with the protective agent coating portion 32 of the solid flocculant portion 10B. and have

The exposed surface 52 of the protective portion 50Ba shown in FIG. 3 includes an exposed flat surface portion 54Ba (54) that is a circular exposed surface 52 that forms the top surface of the cylinder, and a cylindrical exposed surface 52 that forms the side surface of the cylinder. It consists of an exposed curved surface portion 55Ba (55).

Here, S54Ba, which is the surface area of the exposed flat surface portion 54Ba, and S55Ba, which is the surface area of the exposed curved surface portion 55Ba, can be calculated by a known method. The total surface area S52 of the exposed surface 52 forming the protective portion 50Ba is the sum of S54Ba and S55Ba (S54Ba+S55Ba).

Also, the exposed surface 52 of the protective portion 50Bb shown in FIG. It consists of a certain exposed curved surface portion 55Bb.

Here, S54Bb, which is the surface area of the exposed flat surface portion 54Bb, and S55Bb, which is the surface area of the exposed curved surface portion 55Bb, can be calculated by a known method. The total surface area S52 of the exposed surface 52 forming the protective portion 50Bb is the sum of S54Bb and S55Bb (S54Bb+S55Bb).

The total surface area S52 of the exposed surfaces 52 constituting the protective portions 50Ba and 50Bb of the sustained-release solid flocculant 1B is the sum of S54Ba, S55Ba, S54Bb, and S55Bb (S54Ba+S55Ba+S54Bb+S55Bb).

The surface area S54a of the exposed flat portion 54Ba and the surface area S54b of the exposed flat portion 54Bb are easily calculated using the diameter D54 of the exposed flat portions 54Ba and 54Bb, respectively. Further, the surface area S55Ba of the exposed curved surface portion 55Ba and the surface area S55Bb of the exposed curved surface portion 55Bb can be easily determined using the diameter D54 of the exposed flat surface portions 54Ba and 54Bb and the lengths L55Ba and L55Bb of the exposed curved surface portions 55Ba and 55Bb, respectively. Calculated.

(Flocculant surface coverage)
In the sustained-release solid flocculant 1B, part of the surface 12 of the solid flocculant portion 10B is covered with protective portions 50Ba and 50Bb.

In the sustained-release solid flocculant 1B, the flocculant surface coverage ratio is the ratio of the surface covered with the protective portions 50Ba and 50Bb to the surface 12 of the solid flocculant portion 10B. The flocculant surface coverage of the sustained-release solid flocculant 1B is within the same numerical range as the flocculant surface coverage of the sustained-release solid flocculant 1A. The reason for this is the same as the reason for the flocculant surface coverage of the sustained-release solid flocculant 1A, so the explanation is omitted.

In the sustained-release solid flocculant 1B shown in FIG. 3, specifically, the surface area S32 of the protective agent-coated portion 32 is the sum of the surface areas S34Ba and S34Bb of the flat portions 34Ba and 34Bb (S34Ba+S34Bb). The surface area S12 of the surface 12 of the solid flocculant portion 10B is the sum of the surface area S14a of the flat portion 14a, the surface area S14b of the flat portion 14b, and the surface area S15 of the curved portion 15 (S14a+S14b+S15). Therefore, in the sustained-release solid flocculant 1B, the flocculant surface coverage is (S34Ba+S34Bb)/(S14a+S14b+S15).

(Water contact specific surface area ratio)
In the sustained-release solid coagulant 1B, the water contact specific surface area ratio, which is the ratio of the surface area S52 of the exposed surfaces 52 of the protective portions 50Ba and 50Bb to the surface area S22 of the coagulant-exposed portion 22 of the solid coagulant portion 10B, is It is within the same numerical range as the water contact specific surface area ratio of the solid release flocculant 1A. The reason is the same as the reason for the water contact specific surface area ratio of the sustained-release solid flocculant 1A, so the explanation is omitted.

(action)
Since the action of the sustained-release solid flocculant 1B is the same as the action of the sustained-release solid flocculant 1A, the explanation is omitted.

[Third Embodiment]
A sustained-release solid flocculant according to the third embodiment will be described. FIG. 4 is a diagram showing an example of a sustained-release solid flocculant according to the third embodiment. As shown in FIG. 4, the sustained-release solid flocculant 1C(1) includes a solid flocculant portion 10C(10) containing a polymer flocculant and a protective portion that protects the solid flocculant portion 10C from contact with water. 50Ca (50) and 50Cb (50). Further, in the sustained-release solid coagulant 1C, part of the surface 12 of the solid coagulant portion 10C is covered with protective portions 50Ca and 50Cb.

As shown in FIG. 4, the sustained-release solid coagulant 1C according to the third embodiment has a cylindrical shape as a whole by combining the solid coagulant portion 10C, the protective portion 50Ca, and the protective portion 50Cb. ing.

The solid coagulant part 10C of the sustained-release solid coagulant 1C according to the third embodiment is the same as the solid coagulant part 10A of the sustained-release solid coagulant 1A according to the first embodiment except for its shape. be. In addition, the protective portion 50Ca and the protective portion 50Cb of the sustained-release solid coagulant 1C according to the third embodiment are similar to the protective portion 50A of the sustained-release solid coagulant 1A according to the first embodiment except for their shapes. are the same.

For this reason, the same reference numerals are given to the same members in the sustained-release solid coagulant 1C according to the third embodiment and the sustained-release solid coagulant 1A according to the first embodiment. omission or simplification of the description of

(Solid flocculant section)
As shown in FIG. 4, in the sustained-release solid coagulant 1C, a portion of the surface 12 of the solid coagulant portion 10C shown in FIG. 2 is covered with a protective portion 50C.

The solid flocculant section 10C is the same as the solid flocculant section 10A except for the shape. Therefore, the shape of the solid flocculant portion 10C will be described below, and the description of other aspects of the solid flocculant portion 10C will be omitted.

The solid flocculant part 10C is formed by cutting the cylindrical sustained-release solid flocculant 1C along the height direction using two parallel planes, thereby forming two arcuate columns and one It is a member of a rounded rectangular columnar body when it is cut into a rounded rectangular columnar body.

Specifically, the solid coagulant portion 10C of the rounded rectangular columnar body has a cross section obtained by cutting perpendicularly to the height direction of the solid coagulant portion 10C. It is a columnar body which is a rectangle with rounded corners and is composed of two arcuate curves connecting the ends of the column. The two arcuate columnar bodies are protective portions 50Ca and 50Cb.

The solid flocculant portion 10C has six surfaces: flat portions 24Ca(24), 24Cb(24), 34Ca(34) and 34Cb(34), and curved portions 25Ca(25) and 25Cb(25). .

[Protective agent coated part]
In the sustained-release solid flocculant 1C shown in FIG. 4, among the six surfaces, the plane portions 34Ca and 34Cb are protective agent-coated portions 32, which are surfaces coated with the protective portions 50Ca and 50Cb. The plane portions 34Ca and 34Cb are the plane portions 34Ca and 34Cb of the protective agent-coated portion.

The surface areas S34Ca and S34Cb of the planar portions 34Ca and 34Cb of the protective agent-coated portion 32 constituting the solid flocculant portion 10C can be calculated by a known method. The total surface area S32 of the protective agent-covered portions 32 constituting the solid flocculant portion 10C is the sum of S34Ca and S34Cb (S34Ca+S34Cb).

[Coagulant-exposed part]
In the sustained-release solid flocculant 1C shown in FIG. 4, among the six surfaces, the flat portions 24Ca and 24Cb and the curved portions 25Ca and 25Cb are exposed without being covered with the protective portion 50C. It becomes part 22. The flat portions 24Ca and 24Cb are the flat portions 24Aa and 24Ab of the coagulant-exposed portions, and the curved portions 25Ca and 25Cb are the curved portions 25Ca and 25Cb of the coagulant-exposed portions.

The surface areas S24Ca and S24Cb and S25Ca and S25Cb of the planar portions 24Ca and 24Cb and the curved portions 25Ca and 25Cb of the flocculant-exposed portion 22 constituting the solid flocculant portion 10C are calculated by a known method. be able to.

The total surface area S22 of the coagulant-exposed portions 22 constituting the solid coagulant portion 10C is the sum of S24Ca and S24Cb and S25Ca and S25Cb (S24Ca+S24Cb+S25Ca+S25Cb).

(protection part)
The protective parts 50Ca and 50Cb constituting the sustained-release solid flocculant 1C will be described with reference to FIG.

The protective portions 50Ca and 50Cb shown in FIG. 4 are arcuate columnar bodies, respectively, and include an exposed surface 52 exposed to the outside and a portion not exposed to the outside but in contact with the protective agent coating portion 32 of the solid flocculant portion 10C. , has

The exposed surface 52 of the protective portion 50Ca shown in FIG. 52 and an exposed curved surface portion 55Ca (55).

Here, S54Caa and S54Cab, which are the surface areas of the exposed flat surface portions 54Caa and 54Cab, and S55Ca, which is the surface area of the exposed curved surface portion 55Ca, can be calculated by a known method. The total surface area S52 of the exposed surface 52 forming the protective portion 50Ca is the sum of S54Caa and S54Cab and S55Ca (S54Caa+S54Cab+S55Ca).

In addition, the exposed surface 52 of the protection portion 50Cb shown in FIG. It consists of an exposed curved surface portion 55Cb (55) which is the exposed surface 52 .

Here, S54Cba and S54Cbb, which are the surface areas of the exposed flat surface portions 54Cba and 54Cbb, and S55Cb, which is the surface area of the exposed curved surface portion 55Cb, can be calculated by a known method. The total surface area S52 of the exposed surface 52 forming the protective portion 50Cb is the sum of S54Cba and S54Cbb and S55Cb (S54Cba+S54Cbb+S55Cb).

The total surface area S52 of the exposed surfaces 52 forming the protective portions 50Ca and 50Cb forming the sustained-release solid flocculant 1C is the sum of S54Caa, S54Cab, S55Ca, S54Cba, S54Cbb, and S55Cb. This sum is specifically S54Caa+S54Cab+S55Ca+S54Cba+S54Cbb+S55Cb.

(Flocculant surface coverage)
In the sustained-release solid flocculant 1C, part of the surface 12 of the solid flocculant portion 10C is covered with protective portions 50Ca and 50Cb.

In the sustained-release solid flocculant 1C, the flocculant surface coverage ratio is the ratio of the surface covered with the protective portions 50Ca and 50Cb to the surface 12 of the solid flocculant portion 10C. The flocculant surface coverage of the sustained-release solid flocculant 1C is within the same numerical range as the flocculant surface coverage of the sustained-release solid flocculant 1A. The reason for this is the same as the reason for the flocculant surface coverage of the sustained-release solid flocculant 1A, so the explanation is omitted.

In the sustained-release solid flocculant 1C shown in FIG. 4, specifically, the surface area S32 of the protective agent-coated portion 32 is the sum of the surface areas S34Ca and S34Cb of the flat portions 34Ca and 34Cb (S34Ca+S34Cb). The surface area S12 of the surface 12 of the solid flocculant portion 10C is the sum of the surface areas S24Ca, S24Cb, S34Ca and S34Cb of the flat portions 24Ca, 24Cb, 34Ca and 34Cb and the surface areas S25Ca and S25Cb of the curved portions 25Ca and 25Cb. be. Specifically, this sum is S24Ca+S24Cb+S34Ca+S34Cb+S25Ca+S25Cb. Therefore, in the sustained-release solid flocculant 1C, the flocculant surface coverage ratio is (S34Ca+S34Cb)/(S24Ca+S24Cb+S34Ca+S34Cb+S25Ca+S25Cb).

(Water contact specific surface area ratio)
In the sustained-release solid coagulant 1C, the water contact specific surface area ratio, which is the ratio of the surface area S52 of the exposed surfaces 52 of the protective portions 50Ca and 50Cb to the surface area S22 of the coagulant-exposed portion 22 of the solid coagulant portion 10C, is It is within the same range as the water contact specific surface area ratio of the solid release flocculant 1A. The reason is the same as the reason for the water contact specific surface area ratio of the sustained-release solid flocculant 1A, so the explanation is omitted.

(Action)
Since the action of the sustained-release solid flocculant 1C is the same as the action of the sustained-release solid flocculant 1A, the explanation is omitted.

[Reference form]
A solid flocculant according to the reference embodiment will be described. FIG. 5 is a diagram showing an example of a solid flocculant according to the reference embodiment. As shown in FIG. 5, the solid flocculant 5D(5) includes a solid flocculant portion 10D(10) containing a polymer flocculant and a protective portion 50D(50) that protects the solid flocculant portion 10D from contact with water. ) and Moreover, in the solid flocculant 5D, a part of the surface 12 of the solid flocculant portion 10D is covered with the protective portion 50D.

A solid flocculant 5D according to the reference embodiment uses a protective portion 50D (50) instead of the protective portion 50A of the sustained-release solid flocculant 1A according to the first embodiment. It is the same as the release solid flocculant 1A. For this reason, the same reference numerals are given to the same members in the solid flocculant 5D according to the reference embodiment and the sustained-release solid flocculant 1A according to the first embodiment, and the description of the members and their actions is omitted or simplified. become

(Solid flocculant section)
As shown in FIG. 5, in solid flocculant 5D, part of surface 12 of solid flocculant section 10D shown in FIG. 2 is covered with protective section 50D.

The solid flocculant part 10D is the same as the solid flocculant part 10A including the shape. Therefore, description of the solid flocculant section 10D is omitted. However, the protective portion 50D that partially covers the surface 12 of the solid flocculant portion 10D has a different shape from the protective portion 50A that partially covers the surface 12 of the solid flocculant portion 10A.

Specifically, in the solid flocculant 5D, the circular flat portion 14a of the surface 12 of the solid flocculant portion 10D serves as the protective agent-coated portion 32, which is the surface covered with the protective portion 50D. On the other hand, in the solid flocculant 5D, the circular flat portion 14b and the cylindrical curved surface portion 15 of the surface 12 of the solid flocculant portion 10D are exposed without being covered with the protective portion 50D. It's now 22. The protective agent-coated portion 32 and the coagulant-exposed portion 22 will be described below.

[Protective agent coated part]
In the solid flocculant 5D shown in FIG. 5, the flat portion 14a, which is the circular surface of the solid flocculant portion 10D shown in FIG.

The protective agent-coated portion 32 of the solid flocculant 5D shown in FIG. 5 is specifically the flat portion 34D (34) of the protective agent-coated portion. The planar portion 34D of the protective agent-coated portion corresponds to the circular planar portion 14a of the solid flocculant portion 10D shown in FIG.

The surface area S34D of the planar portion 34D of the protective agent-coated portion 32 constituting the solid flocculant portion 10D can be calculated by a known method. The total surface area S32 of the protective agent-covered portions 32 constituting the solid flocculant portion 10D is S34D.

The diameter D34 of the plane portion 34D of the protective agent-coated portion 32 of the solid flocculant portion 10D shown in FIG. 5 is the same as the diameter D14 of the plane portion of the solid flocculant portion 10D. The surface area S34 of the flat portion 34D of the protective agent-coated portion 32 is the same as the surface area S14a of the flat portion 14a. The surface area S34 of the flat portion 34D of the protective agent-coated portion 32 is the same as the surface area S14b of the flat portion 14b.

[Coagulant-exposed part]
In the solid flocculant 5D shown in FIG. 5, the planar portion 14b and the tubular curved surface portion 15 of the solid flocculant portion 10D shown in FIG.

The coagulant-exposed portion 22 of the solid coagulant 5D shown in FIG. 5 is specifically a flat portion 24D (24) and a curved portion 25D (25) of the coagulant-exposed portion. The planar portion 24D of the coagulant exposed portion corresponds to the planar portion 14b of the solid coagulant portion 10D shown in FIG. The curved surface portion 25D of the coagulant exposed portion corresponds to the cylindrical curved surface portion 15 of the solid coagulant portion 10D shown in FIG.

S24D, which is the surface area of the flat portion 24D, and S25D, which is the surface area of the curved portion 25D, can be calculated by a known method. The total surface area S22 of the coagulant-exposed portions 22 constituting the solid coagulant portion 10D is the sum of S24D and S25D (S24D+S25D).

The length L25 of the curved surface portion 35D of the coagulant exposed portion 22 of the solid coagulant portion 10D shown in FIG. 5 is the same as the length L15 of the curved surface portion of the solid coagulant portion 10D. Further, the diameter D24 of the curved surface portion 25D of the flocculant exposed portion 22 is the same as the diameter D34 and the diameter D14 of the flat surface portion of the solid flocculant portion 10D.

(protection part)
The protective portion 50D that constitutes the solid flocculant 5D will be described with reference to FIG.

The protective part 50D is the same as the protective part 50A of the sustained-release solid coagulant 1A according to the first embodiment, except for its shape. Therefore, the shape of the protective portion 50D will be described below.

The protective portion 50D shown in FIG. 5 has a cylindrical outer shape, and has an exposed surface 52 exposed to the outside and a portion not exposed to the outside but in contact with the protective agent coating portion 32 of the solid flocculant portion 10D. .

The exposed surface 52 of the protective portion 50D shown in FIG. 5 includes the exposed flat portion 54D (54), which is the circular exposed surface 52 forming the top surface of the cylinder, and the cylindrical exposed surface 52 forming the side surface of the cylinder. It consists of an exposed curved surface portion 55D (55).

Here, S54D, which is the surface area of the exposed flat surface portion 54D, and S55D, which is the surface area of the exposed curved surface portion 55D, can be calculated by a known method. The total surface area S52 of the exposed surface 52 forming the protective portion 50D is the sum of S54D and S55D (S54D+S55D).

The surface area S54 of the exposed flat portion 54D can be easily calculated using the diameter D54 of the exposed flat portion 54D and the like. Further, the surface area S55D of the exposed curved surface portion 55D is easily calculated using the diameter D54 of the exposed flat surface portion 54D and the length L55D of the exposed curved surface portion 55D.

(Flocculant surface coverage)
In solid flocculant 5D, part of surface 12 of solid flocculant portion 10D is covered with protective portion 50D.

In the solid flocculant 5D, the flocculant surface coverage rate is the ratio of the surface covered with the protective part 50D to the surface 12 of the solid flocculant part 10D. However, the flocculant surface coverage of the solid flocculant 5D is usually lower than that of the sustained-release solid flocculant 1A.

In addition, in the solid flocculant 5D shown in FIG. 5, specifically, the surface area S32 of the protective agent-coated portion 32 is the surface area S34D of the plane portion 34D. The surface area S12 of the surface 12 of the solid flocculant portion 10D is the sum of the surface area S14a of the flat portion 14a, the surface area S14b of the flat portion 14b, and the surface area S15 of the curved portion 15 (S14a+S14b+S15). Therefore, with solid flocculant 5D, the flocculant surface coverage is (S34D)/(S14a+S14b+S15). However, solid flocculant 5D tends to have a flocculant surface coverage of less than 30%.

(Water contact specific surface area ratio)
In the solid flocculant 5D, the water contact specific surface area ratio, which is the ratio of the surface area S52 of the exposed surface 52 of the protective part 50D to the surface area S22 of the flocculant exposed part 22 of the solid flocculant part 10D, is the controlled-release solid flocculant. It is within the same range as the water contact specific surface area ratio of 1A. The reason is the same as the reason for the water contact specific surface area ratio of the sustained-release solid flocculant 1A, so the explanation is omitted.

(Action)
The action of the solid flocculant 5D is the same as the action of the sustained-release solid flocculant 1A, so the explanation is omitted. However, in the solid flocculant 5D, since the degree of covering the solid flocculant portion 10D with the protective portion 50D is generally low, the polymer flocculant is relatively easily eluted from the solid flocculant portion 10D, resulting in sustained release. tends to be low.

<Water treatment equipment>
Next, a water treatment device according to an embodiment will be described. The water treatment device according to the embodiment is a device using the sustained-release solid flocculant 1 according to the embodiment.

Drawing 6 is a key map showing an example of the water treatment equipment concerning an embodiment. As shown in FIG. 6, the water treatment apparatus 500 according to the embodiment includes a pump 200 for sending the water to be treated _W0 to the drug dissolving apparatus 100 and the like, the drug dissolving apparatus 100, and the water discharged from the drug dissolving apparatus 100. and a filter 300 that filters the water _W2 after passing through. A sustained-release solid flocculant 1 according to an embodiment is placed in a drug dissolving device 100 .

In the water treatment apparatus 500 , the water to be treated W ₀ introduced into the introduction line 410 is sent to the main line 420 by the pump 200 . During water treatment, the water to be treated _W0 is introduced into the main line 420, the sustained release introduction line 430, and the drug dissolving device 100. FIG. In the drug dissolving apparatus ₁₀₀ , post-contact water W1 is generated from the water W0 to be treated by water treatment using the sustained _- release solid coagulant ₁ , and is discharged outside the drug dissolving apparatus 100 as water W2 after passage. After-passing water W2 discharged out of drug _- dissolving device 100 flows through sustained release discharge line 440 and main line 460, is introduced into filter 300, is filtered by filter 300, and is treated water TW. Generate. The treated water TW discharged from the filter 300 flows through the discharge line 470 and is discharged.

On the other hand, when water treatment is not performed, the water to be treated _W0 sent to the main line 420 flows through, for example, the untreated line 450 and the main line 460, is introduced into the filter 300, and is introduced into the filter 300. to produce untreated filtered water _W3 . The untreated filtered water W ₃ discharged from the filter 300 is discharged through the discharge line 470 .

(drug dissolving device)
FIG. 7 is a cross-sectional view of an example 100A of the drug dissolving device 100 that constitutes the water treatment device 500 shown in FIG. As shown in FIG. 7, the drug dissolving apparatus 100A includes a container portion 110, a drug tank 120A (120) arranged in the container portion 110, and an introduction portion 130 for introducing the water to be treated _W0 into the container portion 110. And prepare.

The container portion 110 includes a container body portion 111 and a lid portion 112 , and a space is formed inside the container portion 110 by the container body portion 111 and the lid portion 112 . The container main body 111 has a disk-shaped bottom surface 111a and a cylindrical peripheral wall 111b, and has an open upper end. The lid portion 112 is detachably attached to the upper end of the container main body portion 111 . Specifically, the lid portion 112 includes a disk-shaped upper surface portion 112a and a peripheral wall portion extending downward from the outer peripheral end of the upper surface portion 112a and formed to be slightly larger than the peripheral wall portion 111b of the container main body portion 111. 112b. Note that the container part 110 may have a shape different from that shown in FIG. 7 as long as a space can be formed inside.

A drug reservoir 120A containing the sustained-release solid coagulant 1 is arranged in the container part 110 . In the drug dissolving device 100A, by removing the lid part 112 from the container body part 111 and disposing the drug tank 120A in the container part 110, the sustained-release solid flocculant 1 is not touched and is slowly released into the container part 110. It is possible to put in a volatile solid flocculant 1.

As shown in FIGS. 7 and 8, the drug reservoir 120A includes a disc-shaped bottom portion 121 and a cylindrical peripheral wall extending upward from the outer peripheral end of the bottom portion 121 and surrounding the space above the bottom portion 121. a portion 122; The bottom portion 121 of the drug reservoir 120A has a shape such as a substantially square shape that is different from the shape shown in FIGS. It may be in shape. Moreover, the peripheral wall portion 122 may also have a shape such as a rectangular tube shape different from the shapes shown in FIGS. 7 and 8 .

The chemical tank 120A includes an inlet 123 for introducing the water to be treated _W0 and the like into a space surrounded by the peripheral wall portion 122 via the inlet 130, the introduced water to be treated _W0 and the sustained-release solid coagulant. and a discharge port 124 for discharging the post _- contact water W1 obtained by contacting the water W1 to the outside. The introduction port 123 is provided substantially at the center of the bottom surface portion 121 and is a through hole penetrating in a circular shape when viewed from the thickness direction of the bottom surface portion 121 . The discharge port 124 has a circular shape when viewed from the thickness direction of the bottom surface portion 121 . When the water to be treated W0 is supplied to the sustained-release solid flocculant ₁ through the inlet 123, the components such as the polymer flocculant contained in the sustained-release solid flocculant ₁ are dissolved in the treated water W0. By doing so, post _- contact water W1 is obtained. In the drug dissolving device 100A, a dispersing section 145, which will be described later, is placed on the introduction port 123, and the liquid such as the water to be treated _W0 introduced through the introduction port 123 flows through the dispersing section 145. distributed.

The drug dissolving device 100A includes an introduction pipe 151 for introducing the water to be treated _W0 into the bottom surface portion 111a of the container main body 111, and the post _- contact water W1 generated in the drug dissolving device 100A to the outside of the drug dissolving device 100A. and a discharge pipe 152 for discharging as water _W2 after passing through. The space inside the introduction pipe 151 and the space inside the introduction portion 130 constitute an introduction channel 141 . The space outside the introduction part 130 and the space inside the discharge pipe 152 constitute a discharge flow path 142 . A partition wall 153 is provided between the introduction pipe 151 and the discharge pipe 152 to separate them. At the lower end of the discharge pipe 152, a drain plug 154 for removing water inside the drug dissolving device 100A is provided.

It is preferable that the plurality of outlets 124 in the bottom surface portion 121 have the same shape. _The discharge port 124 is not particularly limited as long as it can discharge the water W1 after contact, and its shape, position, number, and the like are not particularly limited. For example, the plurality of discharge ports 124 may be long holes extending in the radial direction, or arcuate holes extending in the circumferential direction. In addition, the position of discharge port 124 in drug tank 120A is not limited to bottom surface portion 121 . The discharge port 124 may be provided in the peripheral wall portion 122, for example. Even in the modified example of the drug tank 120A in which the peripheral wall portion 122 is provided with the discharge port 124, the water to be treated _W0 can be brought into substantially uniform contact with the sustained-release solid coagulant 1. FIG.

As shown in FIG. 8, the peripheral wall portion 122 of the medicine tank 120A is cylindrical. Further, the bottom portion 121 of the medicine tank 120A is disc-shaped, and the imaginary central axis of the cylindrical peripheral wall portion 122 passes through the center of the bottom portion 121 . Eight outlets 124 are provided along the circumference of the bottom portion 121 in the drug tank 120A.

Above the introduction port 123 and the discharge port 124 of the drug tank 120A, the sustained-release solid flocculating agent 1 is arranged between the introduction port 123 and the sustained-release solid flocculating agent 1 so as to cover the introduction port 123. A dispersing section 145 for dispersing the flow of the water to be treated W0 toward the agent ₁ is further provided. In the drug dissolving device 100, the dispersion unit 145 is used to bring the dispersed water to be treated W0 into uniform contact with the entire lower portion of the sustained-release solid flocculant ₁ , so that the water W0 contained in the sustained-release solid flocculant 1 Components such as a polymer flocculant can be dissolved substantially uniformly in the water to be treated _W0 . Further, in the drug dissolving device 100 , by using the dispersing section 145 , for example, it is possible to prevent the granular sustained-release solid coagulant 1 from flowing out from the drug dissolving device 100 all at once. As a result, it is easy to keep the dissolved concentration of the sustained-release solid flocculant ₁ in the water to be treated W0 substantially constant.

The distributed portion 145 is a structure in which a large number of gaps are distributed in the thickness direction and radial direction. Specifically, the dispersed portion 145 is a multi-grain deposit formed by depositing a large number of grains. Since the dispersion part 145 is a multi-grain deposit, it is easily available.

The dispersing portion 145 has the function of dispersing the flow of the water to be treated _W0 that has been introduced into one portion of the inlet 123 by allowing it to pass through the gaps in the dispersing portion 145 . In addition, the dispersing section 145 also has the function of rectifying the flow of the water to be treated _W0 in the chemical tank 120A. The dispersing portion 145 is placed inside the peripheral wall portion 122 and on the bottom surface portion 121 so as to cover the introduction port 123 .

The dispersing part 145 disperses the water _W0 to be treated, and as long as the water to be treated W0 can be brought into substantially uniform contact with the lower part of the sustained-release solid flocculant ₁ , the dispersing part 145 has a structure other than the multi-grain sediment. It can be a body. The dispersion part 145 is, for example, a laminated structure of a plurality of nonwoven fabrics, a laminated structure of a plurality of woven fabrics, a three-dimensional fiber structure in which fibers are entangled, or a porous member having a structure similar to a sponge. may be

As shown in FIG. 8, in the drug dissolving device 100A, a mesh member 125 is placed on the bottom portion 121 formed with the introduction port 123 of the drug tank 120A and below the dispersing portion 145 so as to cover the introduction port 123. be done. Therefore, the mesh member 125 is interposed between the introduction port 123 and the dispersing section 145 in the drug dissolving device 100A. The mesh member 125 has many meshes smaller than the inlet 123 . Further, the mesh of the mesh member 125 is sized to prevent passage of the particles forming the dispersion portion 145, but to allow passage of the water to be treated _W0 .

The introduction part 130 is a substantially cylindrical pipe connected to the introduction port 123 of the bottom surface part 121 from below the bottom surface part 121 . The inside of the introduction part 130 forms an introduction channel 141 through which the water to be treated _W0 flows.

A discharge channel 142 is provided in a space inside the container main body 111 and outside the introduction part 130 of the drug dissolving device 100A. The post _- contact water W1 obtained by dissolving the components such as the polymer flocculant contained in the sustained-release solid flocculant ₁ in the water to be treated W0 is introduced into the discharge channel 142 through the discharge port 124. be done. The post _- contact water W1 flowing through the discharge channel 142 is discharged to the outside of the drug dissolving device 100A through the discharge pipe 152. As shown in FIG. When the post _- contact water W1 is discharged outside the drug dissolving device 100A, it becomes the post _- passage water W2 formed by discharging the water to be treated _W0 from the drug dissolving device 100A. Generally, the post _- contact water W1 flowing through the discharge channel 142 in the drug dissolving device 100A and the post _- passing water W2 discharged out of the drug dissolving device 100A have the same composition.

<Action>
The action of the water treatment device 500 incorporating the drug dissolving device 100A will be described. First, water to be treated W ₀ such as well water is introduced into the introduction pipe 151 . The water to be treated _W0 may contain impurities such as inorganic substances such as Fe, Mn and sand; bacteria and the like. The water W ₀ to be treated passes through the introduction channel 141 in the introduction portion 130 and is introduced into the chemical tank 120A via the introduction port 123 . In the chemical tank 120A, the water to be treated _W0 is introduced into the gaps of the dispersing portion 145, thereby being dispersed. As a result, the water to be treated W0 introduced from below the sustained-release solid flocculant ₁ contacts the sustained-release solid flocculant 1 almost uniformly.

When the water to be treated W0 contacts the sustained-release solid flocculant ₁ , the polymer flocculant in the solid flocculant part 10 dissolves in the water to be treated _W0 to obtain post _- contact water W0. The post _- contact water W1 passes through the discharge port 124 from the inside of the drug tank 120A and flows down to the discharge channel 142 below the discharge port 124 . The post _- contact water W1 flowing through the discharge channel 142 reaches the discharge pipe 152 and is discharged from the drug dissolving device 100 as the post _- contact water W2.

In the post _- contact water W1 and the post _- passage water _W2 , impurities such as suspended substances contained in the water to be treated W0 are captured by the polymer flocculant to form flocs. When the post-contact water W ₁ and the post-passing water W ₂ containing the flocs pass through the filter media in the filter 300 arranged downstream of the drug dissolving device 100, the flocs are removed and the impurity content is reduced. Afterwater TW is obtained.

As long as the protective part 50 has the function of protecting the solid flocculant part 10 from contact with water, it absorbs water, expands, dissolves or disintegrates upon contact with water such as the water to be treated _W0 . , the post-contact water W1 may contain _a protective agent that is a component in the protective portion 50 . When the post-contact water W1 contains _a protective agent, this protective agent can also remove impurities in the water to be treated _W0 . For example, when the protection part 50 is made of a water-soluble chlorine-containing compound, when the water to be treated _W0 containing Fe ions is introduced, the Fe ions and chloride ions react in the post _- contact water W1, An insoluble suspended material may be formed. In this case, filtering the insoluble suspended matter makes it possible to obtain the treated water TW from which the Fe ions have been removed.

The post-contact water W ₁ obtained by contacting the water to be treated W ₀ and the sustained-release solid flocculant 1 has a polymer flocculant concentration of preferably 0.001 mg/L or more and 1000 mg/L or less, more preferably is 0.01 mg/L or more and 1 mg/L or less. When the concentration of the polymer flocculant in the post _- contact water W1 is within the above range, it is preferable because appropriate flocculation is exhibited and water purification performance is improved.

In the case where the water treatment apparatus 500 further includes a drug dissolving device 100 holding the sustained _- release solid flocculant ₁ , the water W2 after passage, which is the water to be treated W0 discharged from the drug dissolving device 100, is a polymer flocculant. It is preferable if the concentration of the agent is within the specified range. That is, the post _- passage water W2 preferably has a polymer flocculant concentration of 0.001 mg/L or more and 1000 mg/L or less, more preferably 0.01 mg/L or more and 1 mg/L or less. It is preferable that the concentration of the polymer flocculant in the post _- passage water W2 is within the above range because appropriate flocculation is exhibited and water purification performance is improved.

If the post-contact water W1 in the drug-dissolving device ₁₀₀ circulates without further treatment in the drug-dissolving device 100 and is discharged outside the drug _- dissolving device ₁₀₀ as water W2 after passing through, the post-contact water W1 and After passage, the composition becomes substantially the same as the water _W2 .

The present embodiment will be described in more detail below with reference to Examples, but the present embodiment is not limited to these.

[Example 1]
(Slow-release solid flocculant)
A sustained-release solid flocculant 1A according to the first embodiment was prepared by the following procedure. As shown in FIG. 1, the sustained-release solid coagulant 1A includes a solid coagulant portion 10A and a protective portion 50A.

<Solid flocculant part>
As a raw material for the solid flocculant part 10A shown in FIG. 1, a polymethacrylate cationic polymer flocculant powder (Mitsubishi Chemical Co., Ltd. KP201G, weight average molecular weight: 3000000) was crushed with a mill mixer and then sieved through a 350 μm sieve. A powder classified by was prepared.

0.7 g of the above flocculant powder was placed in a cylindrical powder molding mold with a diameter of 8.6 mm and pressure-molded at 25° C. and 20 MPa to obtain a flocculant tablet with a diameter of 8.6 mm and a thickness of 10 mm. was taken. This flocculant tablet was used as the solid flocculant part 10A.

<Protection part>
As a raw material for the protective portion 50A shown in FIG. 1, a protective agent tablet containing trichloroisocyanuric acid as a main component (XS- 90H) was prepared. This protective agent tablet was used as the protective portion 50A.

<Preparation of solid release flocculant>
When a coagulant tablet with a diameter of 8.6 mm and a thickness of 10 mm as the solid coagulant portion 10A was fitted into the hollow portion with an inner diameter of 8.6 mm and a thickness of 10 mm of the protective agent tablet as the protective portion 50A, the coagulant tablet shown in FIG. A release solid flocculant 1A was obtained.

<Flocculant surface coverage>
The sustained-release solid flocculant 1A had a flocculant surface coverage of 69.9%.

<Water contact specific surface area ratio>
The sustained-release solid flocculant 1A had a water contact specific surface area ratio of 19.3 (1930%).
(water treatment equipment)
A water treatment device 500 shown in FIGS. 6 to 8 was used.

(Measurement of chlorine concentration and turbidity)
<Device configuration>
First, as the water to be treated _W0 to be introduced into the water treatment apparatus 500, a commercially available kaolin reagent was added to tap water to prepare simulated turbid water with a turbidity of 100 NTU.
Next, six pieces of sustained-release solid flocculant 1A were placed in the drug tank 120 in the drug dissolving device 100 of the water treatment device 500 .

<Water treatment cycle>
Using the water treatment apparatus 500 in which the sustained-release solid flocculant 1A was placed in the chemical bath 120, the following water treatment cycle was performed. First, the water to be treated _W0 was introduced into the water treatment apparatus 500 so that the flow rate of the introduction channel 141 in the drug dissolving apparatus 100 was 15 L/min. In the drug dissolving device 100, the sustained-release solid flocculant 1A was dissolved in the water to be treated _W0 to produce post _- contact water W1. After contact, the water W1 was discharged out of the drug dissolving device ₁₀₀ as water _W2 after passing. After _- passing water W2 discharged from the drug dissolving apparatus 100 was introduced into the filter 300 and filtered to obtain post-treatment water TW. The filter part of the filter 300 had an inner diameter of 250 mm, and was made by depositing 5 L of activated carbon, 6 L of sand filter medium with a particle size of 0.35 mm, and 4 L of gravel with a particle size of 10 mm.
The above treatment was regarded as one cycle of the water treatment cycle, and this one cycle was carried out for one hour.
After one cycle of the water treatment cycle was completed, a backwashing operation was performed to backwash the filter 300 with tap water.

<Repetition of water treatment cycle>
The 1-hour water treatment cycle and the backwashing operation were alternated, and the water treatment cycle was performed 7 times. The total water flow time, excluding the time for backwashing, was 7 hours.

<Measurement of chlorine concentration>
The eluted chlorine concentration [ppm] was measured for the post-passing water W ₂ discharged outside the drug dissolving apparatus 100 and before being introduced into the filter 300 . The results are shown in FIG. Note that the horizontal axis in FIG. 9 is the total value of the water flow time that does not include the time for the backwashing work.
From FIG. 9, it was found that the concentration of eluted chlorine was 5 to 10 ppm over the 7-hour water flow time, so that the concentration fluctuation was small and the protective agent contained in the protective portion 50A could be stably and gradually released.

<Measurement of turbidity>
The turbidity [NTU] of the treated water TW discharged out of the filter 300 was measured. The results are shown in FIG. The horizontal axis of FIG. 10 is the total value of the water flow time that does not include the time for the backwashing work. Moreover, "5NTU" in FIG. 10 indicates the WHO tap water turbidity standard. Furthermore, "50 NTU" in FIG. 10 is the untreated filtered water W discharged from the filter 300 when no sustained-release solid coagulant is placed in the drug tank 120 in the drug dissolving device 100 and water treatment is not performed. ₃ mean turbidity.
From FIG. 10, it was found that the turbidity of the post-treatment water TW was below 5 NTU throughout the 7-hour running time, and that the polymer flocculant contained in the solid flocculant portion 10A could be stably and sustainedly released.

<Situation of remaining solid flocculant part in sustained-release solid flocculant>
In the sustained-release solid flocculant 1A in the drug bath 120, the solid flocculant portion 10 remained even after 7 hours of water flow.

<Evaluation>
The sustained-release solid flocculant 1A of Example 1 is capable of stable and sustained release of two components, the protective agent contained in the protective portion 50A and the polymer flocculant contained in the solid flocculant portion 10A, and the water flow time is 7 It remained after hours. Therefore, the sustained-release solid flocculant 1A of Example 1 was found to be useful as a sustained-release solid flocculant.

[Reference example 1]
<Measurement of turbidity>
Using the water treatment apparatus 500, the turbidity [NTU] of the water to be treated _W0 in the main line 460 before being introduced into the filter 300 without passing through the drug dissolving apparatus 100 was measured. Specifically, the turbidity [NTU] of the water to be treated _W0 in the main line 460 when the water to be treated _W0 was passed through the main line 420, the untreated line 450, and the main line 460 was measured. The results are shown in FIG.
From FIG. 10, it was found that the turbidity of the water to be treated _W0 was about 50 NTU throughout the 7 hours of water flow.

[Example 2]
(Slow-release solid flocculant)
A sustained-release solid flocculant 1A according to the first embodiment was produced in the same manner as in Example 1, except that a different flocculant powder was used as the raw material of the solid flocculant part 10A.
Specifically, as a raw material of the solid flocculant part 10A, polymethacrylate-based cationic polymer flocculant powder (Mitsubishi Chemical Co., Ltd. KP201L, weight average molecular weight: 500000) was crushed with a mill mixer and then sieved with a sieve of 350 μm. The powder classified by was used.

Except for the composition of the solid flocculant part 10A of the sustained-release solid flocculant 1A of Example 2, that is, the shape and size of the solid flocculant part 10A and the protective part 50A of the sustained-release solid flocculant 1A, was the same as the sustained-release solid flocculant 1A. Therefore, the flocculant surface coverage and the water contact specific surface area ratio of the sustained-release solid flocculant 1A of Example 2 were the same as those of the sustained-release solid flocculant 1A of Example 1.

(Measurement of residual rate of solid flocculant part)
First, one piece of sustained-release solid flocculant 1A was immersed in a container in which 100 mL of tap water was stored. Next, the tap water in the container was replaced every hour, and this replacement was repeated 5 times to immerse the sample for a total of 6 hours.
After immersion for 6 hours, the protective portion 50A of the sustained-release solid flocculant 1A and the solid flocculant portion 10A were separated.
The weight W _a of the solid flocculant portion 10A was measured, and W _a was divided by the weight W _b of the solid flocculant portion 10A before the immersion test (W _a /W _b ). This W _a /W _b was defined as the residual ratio of the solid flocculant.
After being immersed for 6 hours, the solid flocculant portion 10A had W _a of 0.527 g and W _b of 0.7 g. Therefore, the residual rate was 75.3%.

[Example 3]
(Slow-release solid flocculant)
A sustained-release solid flocculant 1B according to the second embodiment was prepared by the following procedure. As shown in FIG. 3, the sustained-release solid coagulant 1B includes a solid coagulant portion 10B and protective portions 50Ba and 50Bb.

<Raw material for solid flocculant part>
As a raw material for the solid flocculant part 10B shown in FIG. 3, the same flocculant powder as in Example 2 was prepared.

<Raw material for protective part>
A trichloroisocyanuric acid reagent (XS-90H manufactured by Shikoku Kasei Co., Ltd.) was used as a raw material for the protective portions 50Ba and 50Bb shown in FIG.

<Preparation of solid release flocculant>
First, 0.55 g of protective agent powder was charged into a cylindrical powder molding mold having a diameter of 8.6 mm. Next, 0.7 g of coagulant powder was put on top of the protective agent powder in the powder molding mold. Further, 0.55 g of protective agent powder was put on top of the aggregating agent powder in the powder molding mold. These three layers of powder were pressure-molded at 25° C. and 20 MPa, resulting in a sustained release with a diameter of 8.6 mm, a thickness of the protective portion 50Bb of 5 mm, a thickness of the solid flocculant portion 10B of 10 mm, and a thickness of the protective portion 50Ba of 5 mm. A solid flocculant 1B was obtained.

<Flocculant surface coverage>
The sustained-release solid flocculant 1B had a flocculant surface coverage of 30.1%.

<Water contact specific surface area ratio>
The sustained-release solid flocculant 1B had a water contact specific surface area ratio of 1.4 (140%).

(Measurement of residual rate of solid flocculant part)
The residual ratio of the solid flocculant part was measured in the same manner as in Example 2, except that the sustained-release solid flocculant 1B was used instead of the sustained-release solid flocculant 1A of Example 2.
After being immersed for 6 hours, the solid flocculant portion 10B had W _a of 0.221 g and W _b of 0.7 g. Therefore, the residual rate was 31.5%.

[Reference example 2]
(Solid flocculant)
A solid flocculant 5D was produced by the following procedure. As shown in FIG. 5, the solid flocculant 5D includes a solid flocculant portion 10D and a protective portion 50D.

<Raw material for solid flocculant part>
As a raw material for the solid flocculant part 10D shown in FIG. 5, the same flocculant powder as in Example 2 was prepared.

<Raw material for protective part>
As a raw material for the protective portion 50D shown in FIG. 5, the same protective agent powder as in Example 3 was produced.

<Preparation of sustained-release solid flocculant>
First, 0.7 g of coagulant powder was charged into a cylindrical powder molding mold having a diameter of 8.6 mm. Next, 1.1 g of protective agent powder was put on top of the aggregating agent powder in the powder molding mold. When these two layers of powder were pressure-molded at 25° C. and 20 MPa, solid flocculant 5D having a diameter of 8.6 mm, a thickness of solid flocculant portion 10D of 10 mm, and a thickness of protective portion 50D of 10 mm was obtained.

<Flocculant surface coverage>
Solid flocculant 5D had a flocculant surface coverage of 15.0%.

<Water contact specific surface area ratio>
Solid flocculant 5D had a water contact specific surface area ratio of 1.0 (100%).

(Measurement of residual rate of solid flocculant part)
The remaining ratio of the solid flocculant portion was measured in the same manner as in Example 2, except that the solid flocculant 5D was used instead of the sustained-release solid flocculant 1A of Example 2.
After being immersed for 6 hours, the solid flocculant portion 10D had W _a of 0.125 g and W _b of 0.7 g. Therefore, the residual rate was 17.9%.

[Comparative Example 1]
(Solid flocculant)
The solid flocculant part 10A of Example 2 was used as it was as the solid flocculant 5E. The solid flocculant 5E consists of only the solid flocculant section 10A shown in FIG. 2, and is the same member as the solid flocculant section 10A, but is referred to as the solid flocculant 5E for convenience. Therefore, the solid flocculant 5E does not have the protective portion 50. FIG.

<Flocculant surface coverage>
Since the solid flocculant 5E did not have the protection part 50, the flocculant surface coverage was 0%.

<Water contact specific surface area ratio>
Since the solid flocculant 5E did not have the protection part 50, the water contact specific surface area ratio was 0 (0%).

(Measurement of residual rate of solid flocculant part (solid flocculant))
In the same manner as in Example 2, except that instead of the sustained-release solid flocculant 1A of Example 2, a solid flocculant 5E consisting only of the solid flocculant part 10A was used. The survival rate was measured.
After being immersed for 6 hours, the solid flocculant portion 10A (solid flocculant 5E) had a Wa of 0 g and _a _Wb of 0.7 g. Therefore, the residual rate was 0%.

From the results of Examples 1 to 3, Reference Examples 1 and 2, and Comparative Example 1, the protective portion 50 covers the surface of the solid flocculant portion 10 at a specific ratio, so that the residual rate of the solid flocculant portion 10 is high. It turned out to be

The sustained-release solid coagulant and water treatment device according to the above embodiments can be applied to building entrance-installed water purifiers (POE), place-of-use installed water purifiers (POU), and the like.

The entire contents of Japanese Patent Application No. 2021-025107 (filing date: February 19, 2021) are incorporated herein.

Although the present embodiment has been described above, the present embodiment is not limited to these, and various modifications are possible within the scope of the gist of the present embodiment.

According to the present disclosure, it is possible to provide a sustained-release solid flocculant having sustained release properties of a polymer flocculant and a water treatment apparatus using the sustained-release solid flocculant.

1, 1A, 1B, 1C Slow-release

solid flocculants

5, 5D, 5E

Solid flocculants

10, 10A, 10B, 10C, 10D Solid flocculants 12

Surfaces

50, 50A, 50Ba, 50Bb, 50Ca, 50Cb, 50D Protection Part 100 drug dissolving device 500 water treatment device

Claims

a solid flocculant part containing a polymer flocculant;
and a protection part that protects the solid flocculant part from contact with water,
A sustained-release solid flocculant, wherein a part of the surface of the solid flocculant part is covered with the protective part.
The sustained-release solid flocculant according to claim 1, wherein the polymer flocculant has a weight average molecular weight of 1000 or more.
3. The sustained-release solid flocculation according to claim 1 or 2, wherein the flocculant surface coverage, which is the ratio of the surface of the solid flocculant portion covered with the protective portion, is 20% or more and 99% or less. agent.
The sustained-release solid flocculant according to any one of claims 1 to 3, wherein the protective agent contained in the protective part is mainly composed of a chlorine compound or a polysaccharide.
The sustained-release solid flocculant according to any one of claims 1 to 4, wherein the polymer flocculant is a cationic polymer flocculant.
The sustained-release solid flocculant according to claim 4 or 5, wherein the protective agent is mainly composed of dichloroisocyanuric acid or trichloroisocyanuric acid.
A water treatment device using the sustained-release solid flocculant according to any one of claims 1 to 6.
The post-contact water obtained by contacting the water to be treated with the sustained-release solid flocculant according to claim 7, wherein the concentration of the polymer flocculant is 0.001 mg/L or more and 1000 mg/L or less. Water treatment equipment.
further comprising a drug dissolving device that holds the sustained-release solid flocculating agent,
8. The water treatment apparatus according to claim 7, wherein the post-passage water obtained by discharging the water to be treated from the drug dissolving apparatus has a concentration of the polymer flocculant of 0.001 mg/L or more and 1000 mg/L or less.