JPH09174046A - Water purifying apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water purifying apparatus suitable for purifying water of lakes and marshes, a landscaping basin or rivers, having a simple structure and high safety, good in water purifying treatment efficiency, not requiring the supply of energy or complicated maintenance and low in running cost. SOLUTION: A water purifying apparatus 10 is constituted by providing a molded object 16 formed by fixing ropes 12 made of a glass fiber being a support having a strip shape to a frame member 14 in a reticulated form and hollow spheres 18 made of a synthetic resin being the floats fixed to the molded object 16, and the molded object 16 and the hollow spheres 18 are fixed through pillar parts made of a synthetic resin and the molded object 16 is positioned at a depth of 2mm-10cm. A titanium oxide powder 22 being a photocatalyst is supported on the surfaces of the ropes 12 made of a glass fiber.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a water purification device,
More specifically, the present invention relates to a water purification device with good treatment efficiency, which is suitable for use in lakes, rivers, artificial landscape ponds in watershed parks and watershed parks, and which applies oxidative decomposition by photocatalytic activity.

[0002]

2. Description of the Related Art At present, as the water purification method for lakes, rivers, artificial ponds in watershed parks and water parks, and waterways, methods such as biological treatment, filtration, ultraviolet oxidation and ozone oxidation are used. However, ultraviolet oxidation, ozone oxidation, etc. require high energy input, and in biological treatment and filtration, maintenance such as atmosphere control and filter medium purification to maintain a desired treatment capacity is required, Moreover, both methods have a problem that the treatment efficiency is low for low-concentration pollution with BOD value of 10 mg / liter or less, such as an artificial pond, as compared with high-concentration pollution. There was a problem that the initial equipment cost and treatment cost would be high for water in lakes and rivers that have a large amount of water.

[0003] In particular, when fish and shellfish are reared in the Shukei pond, algae are generated due to organic substances and nutrient salts contained in the excrement of the fish and shellfish, and the ammonia concentration in water increases, resulting in water pollution and odor. May occur, which may adversely affect seafood. However, chemicals such as algicides cannot be used because they have a strong influence on seafood, and an effective water purification treatment method has not been found.

In addition, it is important to maintain clean and safe water quality in artificial ponds and waterways of urban hydrophilic parks where water can be played, and therefore water treatment by chemicals etc. has been unsuitable. .

On the other hand, when a substance having photocatalytic activity (hereinafter referred to as a photocatalyst) such as titanium oxide is irradiated with ultraviolet rays, radicals having a strong oxidizing ability are generated, and the radicals generate substances to be oxidized in liquid and gas. It is known to be oxidized.

[0006] It has been proposed to apply the photocatalytic activity to purify a fluid, for example, Japanese Patent Publication No. 4-54.
No. 511 describes a method of purifying a fluid, in which titanium oxide is made into a porous lump with a translucent substance, dispersed in the fluid, and photodecomposed by irradiation with ultraviolet rays. According to this method, since titanium oxide is formed into a lump by the binder, there is a problem that the surface area involved in the photocatalytic reaction is reduced and the reaction efficiency is poor.

Further, a method has been proposed in which glass beads coated with a photocatalyst such as titanium oxide used as a method for treating spilled oil are dispersed in water, but the used photocatalyst cannot be recovered and the glass beads themselves. However, there are problems such as secondary pollution due to the above and high cost.

[0008]

Therefore, an object of the present invention is a simple structure, which is suitable for use in a scenic pond, an artificial pond in a water park, a waterway, etc., has a high safety, and purifies water. It is an object of the present invention to provide a water purification device having a good treatment efficiency and a low running cost that does not require energy supply or complicated maintenance.

[0009]

As a result of earnest studies, the present inventors have found that a substance having a photocatalytic activity (hereinafter, appropriately referred to as a photocatalyst) is a string-shaped or hollow tube-shaped support, preferably a support surface. The present invention has been completed by finding that the above problems can be solved by using a material supported on the.

A water purifying apparatus according to claim 1 of the present invention is a molded body in which a substance having a photocatalytic activity is carried on a support having a string-like shape or a hollow tube-like shape and fixed to a frame, and a molded article. And a floating body fixed to the molded body, wherein when the floating body floats on the water surface, the molded body and the molded body are arranged so that the molded body is located in water at a depth that sunlight can reach. It is characterized in that it is fixed to a floating body.

From the viewpoint of effect, it is preferable that the molded body is fixed to the floating body so as to be positioned at a water depth of 2 mm to 10 cm.

The material of the support is preferably selected from glass, fibers, synthetic resins, ceramics, zeolite and activated carbon, and the string-like support is thread-shaped,
It is preferable to have a rope shape or a tape shape.

According to this apparatus, a pollutant in water such as a scenic pond is brought into contact with a photocatalyst such as titanium oxide and reacted by irradiation of sunlight, so that the reaction rate is fast and the photocatalytic reaction is highly efficient. You can By this reaction, COD is reduced by the oxidation of oxidizable substances in water, nitrification of ammonia generated in water, sterilization of fungi such as Escherichia coli is performed, and water in ponds, waterways, etc. is supplied with energy from other sources. Instead, the purification process can always be performed efficiently.

In the water purifying apparatus according to claim 2 of the present invention, the molded body carrying the photocatalyst has a water depth of 2 mm to 1 mm.
Since it is fixed so as to be positioned at 0 cm, the intensity of the sunlight irradiating the photocatalyst is kept in a suitable range, and the contact state with water is good, so that the photocatalytic reaction efficiency can be improved.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) FIG. 1 is a schematic perspective view showing the structure of a water purification apparatus 10 according to Embodiment 1.

The water purifying apparatus 10 shown in FIG. 1 has a molded body 16 in which a rope 12 made of glass fiber, which is a support having a string-like shape, is fixed to a frame body 14 in a net shape, and a floating body fixed to the molded body 16. The hollow sphere 18 made of synthetic resin, which is the body.

The molded body 16 and the hollow sphere 18 are fixed to each other via a column portion 20 made of synthetic resin.

On the surface of the glass fiber rope 12, titanium oxide powder 22, which is a substance having photocatalytic activity, is carried.

FIG. 2 is a schematic sectional view showing a state in which the water purification device 10 of the first embodiment is placed in water. The hollow sphere 18 made of synthetic resin floats on the water surface, and the molded body 16 fixed to the hollow sphere 18 through the column 20 is located in water.

Here, the molded body 1 located underwater from the water surface
The distance to 6 (represented by d in FIG. 2), that is, the water depth is preferably about 2 mm to 10 cm. When the molded body 16 is located at a shallower depth than 2 mm,
Depending on the conditions, the net-like glass fiber rope 12 supporting the photocatalyst that constitutes the molded body 16 is exposed on the water surface, which is not preferable in terms of photocatalytic reaction efficiency. Moreover, when the molded body 16 is positioned deeper than 10 cm in water depth,
Ultraviolet rays of an effective wavelength contained in sunlight reaching the photocatalyst surface are attenuated, and the photocatalytic reaction efficiency is reduced.

That is, in order to efficiently carry out the photocatalytic reaction, ultraviolet rays (for example, a wavelength of 360
nm) is preferably 0.1 mW / cm ² or more, and the illuminance of ultraviolet rays of the above wavelength is about 5 mW / cm ² when the sunlight is fine.

Position of molded body 16 in water (water depth)
Can be adjusted according to the floating state of the floating body 18 on the water surface, the distance between the molded body 16 and the floating body 18, and the like. This adjustment can be usually adjusted by the length of the column portion 20 that fixes the molded body 16 and the floating body 18, the weight of the molded body 16, and the like. Further, the fixation between the molded body 16 and the floating body 18 does not necessarily have to be through the column portion 20, and if the distance d from the water surface to the molded body 16 in the water is within the preferable range, the schematic cross-sectional view of FIG. As shown in, the molded body 16 and the floating body 18 may be directly fixed to each other.

The floating body 18 used here is a hollow sphere made of synthetic resin, but if the molded body 16 can be held at a suitable position below the water surface, its size, shape, The material is not particularly limited, and may be a hollow body made of an inorganic material such as glass or ceramic in addition to a synthetic resin, and may be formed of a material having a low specific gravity, such as expanded polystyrene or wood.

By arranging this water purification device 10 in a lake or a river, the surface of the titanium oxide powder 22 carried on the glass fiber rope 12 located near the water surface and the contact surface with water are exposed to the ultraviolet rays of sunlight. A photocatalytic reaction occurs to decompose or sterilize pollutants such as TCE, PCE and ammonia.

When the rope 12 carrying the photocatalyst is fixed in a net-like manner as in the first embodiment, the water is agitated at the net-like portion in a place where the water moves largely, and the water to be treated and the photocatalyst are treated. As the contact frequency with 22 improves,
Dissolution of oxygen required for the photocatalytic reaction from the atmosphere, contact between the surface of the photocatalyst 22 and the water to be treated, and separation of decomposition products are promoted, so that reduction in reaction efficiency can be prevented. further,
The net shape is preferable because it has high strength against external stress such as twisting and bending. This feature is similarly expressed in, for example, a lattice-shaped form.

The size of the water purifier 10 is not particularly limited, but considering the reaction efficiency and portability per piece, the frame body 14 of the molded body 16 having a size of about 2 m × 4 m has good usability. Is.

The water purifying device 10 has a size of a lake or a river,
Depending on the state of contamination, a plurality of them may be connected and used.
In rivers, etc., to prevent loss, it may be tied to the shore with ropes and used. (Embodiment 2) FIG. 4 is a schematic perspective view showing the structure of a water purifier 24 of Embodiment 2.

In the second embodiment, the photocatalyst 22 is carried on the surface of a wide tape-shaped support 26, the tape-shaped supports 26 are arranged in parallel, and both ends are fixed to the frame 14. Other than that, it is the same as the first embodiment.

According to this aspect of the molded body, a large light receiving area can be obtained, and the molding can be easily performed. The width and the fixed interval of the tape-shaped support 26 can be selected depending on the contamination state of the water to be treated, etc.
Those having a size of about cm are preferably used. (Embodiment 3) FIG. 5 is a schematic perspective view showing the structure of a water purifier 28 of Embodiment 3.

In the third embodiment, the photocatalyst 22 is carried on the surface of a hollow tube-shaped support 30 made of glass or porous ceramic and having a diameter of about 2 to 30 mm.
This hollow tube-shaped support 30 is fixed in the form of a wire 32 passing through the hollow portion, the wires 32 are arranged in parallel, and both ends are fixed to the frame body 14, but the same as in the first embodiment. Is.

When a large amount of suspended matter is present on the surface of the water to be treated, if it is an ordinary support, suspended matter may adhere to the surface of the photocatalyst 22 to lower the photocatalytic reaction efficiency. By supporting the photocatalyst 22 on the hollow tubular support 30 rotatably fixed as in Example 3,
The friction of rotation can prevent the adherence of suspended matter to the surface of the photocatalyst 22. The size and arrangement density of the rotatably fixed hollow-tube-shaped support 30 can be arbitrarily selected according to the purpose.

Titanium oxide is used as a photocatalyst in these processing devices 10, 24, 28, but the photocatalyst is not limited to this, and for example, Japanese Patent Publication No. 2-9.
A substance known as a substance having a photocatalytic activity as described in No. 850 can be optionally used. Among the photocatalysts, titanium oxide, iron oxide, tungsten oxide, zinc oxide, strontium titanate and the like are widely known as typical ones, among them, the photocatalytic activity effect, the viewpoint of safety and cost, and, From the viewpoint of adsorbing a phosphate compound in water, titanium oxide used in each example is preferable.

Further, in order to improve the photocatalytic activity of these photocatalysts, it is made of a metal that can coexist with these and become a reduction reaction site in the photocatalytic reaction, for example, platinum, gold, palladium, silver, copper, nickel, cobalt. A metal selected from the group, preferably platinum, gold, palladium, silver or the like can be used in combination.

As the support for supporting the photocatalyst, a substance which can be formed into a string shape or a hollow tube shape, is not deteriorated by a photocatalytic reaction, and is durable and easy to process can be arbitrarily used. From the viewpoint of durability and processing into a fiber shape and capable of taking a large surface area, the glass fiber made of the glass of this example is the most suitable,
In addition, fibers, synthetic resins, ceramics, zeolite, activated carbon and the like can be preferably used. Suitable fibers include carbon fibers and synthetic fibers having excellent durability. Further, as the ceramic, it is preferable to use a porous ceramic from the viewpoint that a large surface area can be obtained.

When the water to be treated is slightly turbid and the absorption of sunlight is large, transparent glass or glass fiber is used as the material of the support to scatter the incident light inside the glass and to reach a deep portion of the photocatalyst. It is preferable to allow the reaction to proceed effectively. When the concentration of oxidant in the water to be treated is high, it is preferable to add zeolite or activated carbon to immobilize the photocatalyst to adsorb and concentrate the oxidizable substance and improve the removal rate. Further, the photocatalytic reaction can be promoted by adding a trace amount of copper or iron.

These materials can be processed into filaments or fibers and used as filaments such as single yarns, twisted yarns and aligned yarns. Further, it is possible to use several yarns by twisting them together to form a rope, or weaving these yarns into a wide tape. In addition, a synthetic resin or the like can be formed into a film shape and cut into a string shape or a tape shape before use.

Inorganic materials such as glass and ceramics and synthetic resins can be used by molding them into a hollow tube shape in addition to the above string shape and tape shape.

The shape of the support is preferably as large as possible in terms of surface area, and from that point of view, a twisted yarn, rope or woven fabric is preferable to a tape-shaped one obtained by cutting a monofilament or a film. From a microscopic point of view, it is more preferable that the fibers have fine whisker-like fibers branching out. Further, in the case of a solid material, a material having fine irregularities on its surface or a material having a multi-layered quality can be cited as a suitable example. These can be arbitrarily selected according to the purpose.

As a method for forming a titanium oxide film on the surface of the support, any known method can be used.
For example, a method in which titanium oxide sol is applied on a support by spin coating, dip coating, etc. and fired if desired, a method in which titanium oxide formed into a film is adhered to the support can be used.

As another method of forming a titanium oxide film, titanium oxide slurry (titanium oxide powder dispersed in water at a concentration of 10 to 20 g / liter) is sprayed under an ultraviolet irradiation condition and dried. , A method of firing.

The support processed into a string shape or a hollow tube shape and carrying a photocatalyst on the surface is used by being fixed to an appropriate frame. The material of the frame is not particularly limited as long as it satisfies the requirements of durability and strength when used in water,
Known materials such as rust-prevented metal, synthetic resin having good water resistance and weather resistance can be used.

From the viewpoint of efficiently taking the light receiving surface, the support is fixed to the frame by a method in which the support members are knitted and woven and fixed in a net shape, a method in which the support is fixed in a lattice shape parallel to the vertical and horizontal directions, and a wide width. A method of arranging and fixing tape-shaped supports in parallel, by fixing the wire to the frame by passing the wire through the hollow part of the hollow-tube-shaped support, and fixing the hollow-tube-shaped support rotatably And the like.

In this water purifying apparatus, since the photocatalyst itself has a stain adhesion preventing property and a sterilizing property, almost no maintenance is required, but a decrease in photocatalytic activity due to physical adhesion of a titanium oxide film is recognized. In such a case, it is preferable from the viewpoint of effectiveness that the water purifying device is once recovered and maintenance for cleaning the photocatalyst surface is appropriately performed.

Further, in the water purifying apparatus of the present invention, a reflective light condensing plate such as a reflector for more efficiently concentrating sunlight on the photocatalyst surface can be fixed and used at a suitable position on the water surface. . Further, from the viewpoint of improving the efficiency of the photocatalytic reaction, an ultraviolet light source such as a black light may be arranged and used in order to maintain the purification function even when sunlight is not irradiated.

When the water purification apparatus of the present invention is applied to scenic ponds and artificial ponds, these may be used alone or in combination, and may be used by floating on the water surface.
When it is used in a waterway, it may be fixed to a seawall or the like with a rope to prevent it from being washed away.

The water purifying apparatus of the present invention is applied to the environment,
A suitable mode can be selected depending on the contamination state, for example, the presence or absence of organisms such as fish, the number of users, and the like.

The mode suitable for the treatment capacity is, for example, the size of the water purification device, the shape of the support, the type of photocatalyst used,
Suitable conditions can be achieved by adjusting the arrangement density of the support supporting the photocatalyst and the like.

The water purification apparatus of the present invention can be used in all fields requiring high water quality and safety, such as a scenic pond, an artificial pond in a water park, an artificial stream, a waterway, etc. It can be preferably used in an aqueous system with many pollutant concentrations.

As described above, the water purifying apparatus of the present invention has a simple structure. Therefore, the arrangement, collection and removal of the apparatus can be easily performed, energy supply and complicated maintenance are not required, and the safety is ensured. Its versatility has a wide range of applications.

[0050]

Industrial Applicability The water purification apparatus of the present invention is suitable for use in artificial ponds, waterways, etc. in a scenic pond, a water park, and is highly safe.
It has a simple structure, good water purification efficiency, and has an excellent effect that high energy supply and complicated maintenance are not required.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an outline of a water purification device according to a first embodiment.

FIG. 2 is a schematic cross-sectional view showing a state in which the water purification device according to the first embodiment is placed in water.

FIG. 3 is a schematic cross-sectional view showing a state in which a water purification device in which a floating body and a molded body are directly fixed to each other is arranged in water.

FIG. 4 is a perspective view showing an outline of a water purification device according to a second embodiment.

FIG. 5 is a perspective view showing an outline of a water purifying apparatus according to a third embodiment.

[Explanation of symbols]

 10 Water Purification Device 12 Glass Fiber Rope (Support) 14 Frame 16 Molded Body 18 Floating Body 22 Titanium Oxide (Substance Having Photocatalytic Activity) 24 Water Purification Device 26 Tape-shaped Support 28 Water Purification Device 30 Hollow Tube-shaped Support 32 wire

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takahisa Ogawa 1-5 Otsuka, Inzai-cho, Inba-gun, Chiba Inside Takenaka Corporation Technical Research Institute (72) Inventor Takeshi Hiromatsu 1-5 Otsuka, Inzai-cho, Inba-gun, Chiba Prefecture Bannaka Takenaka Corporation Technical Research Institute

Claims (4)

[Claims] 1. A molded body in which a substance having a photocatalytic activity is carried on a support body having a string-like shape or a hollow tube shape and fixed to a frame body, and a floating body fixed to the molded body is provided. A water purification device, characterized in that when the floating body floats on the water surface, the molded body and the floating body are fixed so that the molded body is located in water at a water depth that sunlight can reach. Water purifier to be. 2. The water purification apparatus according to claim 1, wherein the molded body is fixed to the floating body so as to be located at a water depth of 2 mm to 10 cm. 3. The water purifying apparatus according to claim 1, wherein the support is selected from glass, fibers, synthetic resins, ceramics, zeolite, and activated carbon. 4. The string-shaped support is thread-shaped, rope-shaped,
Alternatively, it has a tape-like shape.
Or the water purifier according to 2.