JPH03154698A - Method for improving dissolved oxygen amount in limited water area and fish shelter structure using the same - Google Patents

Abstract

PURPOSE:To increase the amount of dissolved oxygen in a water area by providing a partition wall for preventing the diffusion of a rising stream around the water area and injecting O2-containing gas in the water area while utilizing the rising force of the rising stream flowing from below to above to form flow becoming a revolving stream wherein the rising stream naturally flows from above to below within the water area. CONSTITUTION:An air diffusion apparatus 10 performs aeration operation by injecting O2-containing gas. A rising stream 110 is generated by the rising force of many air bubbles generated at this time and O2 contained in many air bubbles is dissolved in the rising stream to increase the amount of dissolved oxygen in the rising stream. Further, the rising stream 110 naturally flows from above to below by a partition wall 14 to form the flow becoming a revolving stream 120 and water increased in the amount of dissolved oxygen is not diffused to the circumference to be prevented from dilution. Therefore, the amount of dissolved oxygen in the water area increases to an amount necessary for keeping and activating an ecological system and, at the same time, the water area can be also purified.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a method for increasing the amount of dissolved oxygen in a predetermined limited water area and improving the amount of dissolved oxygen in the water area, and a fish nest structure using the same. Regarding.

[Conventional technology] Due to water pollution in recent years, rivers, lakes, and the sea have become depleted of dissolved oxygenffl.
(Do) has decreased and the biological system has been destroyed in many places. For this reason, a proposal has been made to install an air diffuser in a predetermined water area and to eject a gas containing at least 02 from the air diffuser to perform aeration.

This conventional technique is shown in FIG. 8, in which an air diffuser [0] is installed at the bottom of a restricted water area 100 to be purified, and a gas containing 02 is spouted to perform aeration. Due to the buoyancy of the bubbles generated by this aerage gin, an upwelling flow shown by an arrow 110 is generated, and 02, which rises with this upwelling flow, dissolves in water and increases the amount of dissolved oxygen.

[Problems to be Solved by the Invention] However, although this conventional technology can increase the amount of dissolved oxygen in the water area 100 to some extent, the water with increased amount of dissolved oxygen diffuses into the surrounding area in a short time and becomes diluted. It will be done.

In particular, in such conventional technology, when there is a flow shown by arrow A in the water area 100, the upwelling flow 110 generated by the aerage gin itself flows in the direction of flow A, so that the amount of dissolved oxygen is increased. Diffusion and dilution of water proceeds at a faster speed.

Therefore, this conventional technology can be used for purification in designated water areas, fish farms, etc.
Even if attempts were made to use it to improve the amount of dissolved oxygen in fish nests at marine farms, etc., there was a problem in that it was not possible to secure a sufficient amount of dissolved oxygen required for maintaining and activating biological systems.

The present invention has been made in view of such conventional problems, and its purpose is to provide a method for improving the amount of dissolved oxygen that can increase the amount of dissolved oxygen in a predetermined limited water area.

Furthermore, another object of the present invention is to maintain a predetermined biological system within a confined water area that constitutes a fish nest space.

The object of the present invention is to provide a fish nest structure capable of obtaining a sufficient amount of dissolved oxygen required for activation.

[Means for solving problems]

In order to achieve the above object, the method of the present invention uses an aeration device to blow out a gas containing at least 02 to form an upwelling flow from below to above a predetermined limited water area, and also includes: A partition wall is installed around the area to prevent upwelling from dispersing, and by utilizing the upward force of upwelling, the upwelling flows naturally form a swirling flow from upward to downward within the restricted water area. It is characterized by increasing the amount of dissolved oxygen in water bodies.

In addition, in order to achieve the other object, the fish nest structure of the present invention includes a diffuser that spouts gas containing at least 02 toward the limited water area of the fish nest space to form an upwelling flow from below to above. and a bulkhead installed around the limited water area to prevent the upwelling from dispersing, which utilizes the upward force of the upwelling to form a flow that naturally turns the upwelling into a swirling flow from above to below. and , and is characterized by increasing the amount of dissolved oxygen within the confined water area of the fish nest space.

[Function] First, in the present invention, an aeration device is used to perform aeration in which a gas containing at least 02 is ejected toward a predetermined limited water area, thereby forming an upwelling flow from below to above the limited water area. As a result, the 02 that rises with the upwelling flow melts into water, increasing the amount of dissolved oxygen in the restricted water area.

Furthermore, in the present invention, a partition wall is installed around this limited water area to prevent the upwelling from dispersing, and by utilizing the upward force of the upwelling, the upwelling flows naturally turn into a swirling flow directed from above to below. form a flow.

In this way, according to the present invention, in a confined water area surrounded by a partition wall, the upwelling flow generated by aeration naturally forms a swirling flow from above to below, and dissolved oxygen The increased amount of water does not diffuse and dilute into the surroundings.

Therefore, the amount of dissolved oxygen in this limited water area can be increased to the amount necessary for maintaining and activating the biological system, and at the same time, the water area can be purified.

In particular, by applying this method of improving the amount of dissolved oxygen to the confined water area that makes up the fish nest space, it is possible to ensure a sufficient amount of dissolved oxygen necessary for maintaining and activating the biological system within the fish nest space. Therefore, the present invention can be applied to fish farms, for example, in bays, lakes, and rivers.

Fish nest structures such as marine farms are extremely suitable.

Furthermore, since the present invention can ensure a sufficient amount of dissolved oxygen within the fish nest space, if conditions sufficient to promote photosynthesis are also set within the fish nest space, plants will flourish and food for fish will be secured. The food chain can be stimulated, and the biological system within the water area can be maintained and activated more effectively.

In order to promote such photosynthesis, for example, a fish nest structure is formed so that natural light or light source light is input from one end of an optical fiber and the light is emitted from the other end to a predetermined part of the fish nest space. It is preferable to do so.

Furthermore, it is also preferable to insert the other end of the optical fiber into a phytoplankton incubator or the like and use this incubator to promote plankton reproduction within the fish nest space.

[Embodiments] Next, preferred embodiments of the present invention will be described in detail with reference to the drawings.

FIRST EMBODIMENT FIG. 2 shows an example of a marine farm to which the present invention is applied, and the marine farm consists of a plurality of fish nest structures 20-1°20 each having a grid-shaped fish nest space 200. -2. It is formed by arranging...

FIG. 1 shows a schematic cross-sectional view of the fish nest structure 20, and FIG. 3 shows a schematic plan view thereof.

The fish nest structure 20 of the embodiment includes a plurality of air diffusers 10 provided at the center of the bottom of the fish nest space 20 and a partition wall 14 for preventing upwelling flow diffusion installed around the fish nest space 200. include.

The air diffuser 10 communicates with the air diffuser of another adjacent fish nest structure 20 via the air duct 12, and
An aeration operation is performed to blow out a gas containing, for example, air. Due to the rising force of the many bubbles generated at this time,
In the fish nest space 200, an upwelling flow 1 flows upward from below.
10 is generated, and 02 contained in a large number of bubbles is melted into the upwelling flow, thereby increasing the amount of dissolved oxygen.

Furthermore, if the diffusion prevention partition wall 14 installed near the water surface is formed using a non-water permeable material as in the embodiment,
The partition wall itself must be formed to have sufficient strength against the flow of water. Therefore, in this embodiment, the partition wall 14 is formed using a porous curtain 22 having water permeability. As a result, some of the water flowing toward the porous curtain 22 passes through the curtain 22, so the pressure acting on the curtain 22 itself is reduced, increasing its mechanical strength and the members supporting it. The strength of can be reduced.

In particular, such a porous curtain 22 is extremely suitable for forming a fish nest structure in a water area where water flows, and the required water permeability is also suitable for forming a fish nest structure in a water area where water flow exists. Any one can be used as necessary as long as it does not prevent the rising flow 110 from forming the swirling flow 120.

Further, the porous curtain 22 defines a limited water area 100 that extends from the water surface of the fish nest space 200 to a predetermined depth, and is laid so as to surround the limited water area 100 in a square shape. In order to maintain the curtain 22 in a vertical position, a float 24 whose upper end is placed above the sea surface
It is fixedly attached, and its central and lower ends are supported by a wire 26 fixed to the seabed.

In this case, the porous curtain 22 has a predetermined water permeability coefficient, and has durability, cold resistance, chemical resistance,
It is preferable to use a sheet made of a material that is excellent in various properties such as weather resistance, and in the example, a high-strength polyester synthetic fiber is used. At this time, the hydraulic conductivity coefficient is preferably set appropriately depending on the environment in which the fish nest structure 20 is used, and in the example, it is 1.40X io -' to 7.5.
A polyester synthetic fiber having a water permeability coefficient of about X 10-' is used.

In this way, by covering the circumference of the restricted water area 100 with the porous curtain 22, the upwelling flow 110 naturally becomes a swirling flow 120 from above to below by utilizing the upward force of the upwelling flow 110. This can prevent water with an increased amount of dissolved oxygen from diffusing into the surrounding area and diluting it.

Therefore, by performing aeration using the fish nest structure of the present invention, the amount of dissolved oxygen in the fish nest space 200 can be sufficiently increased to a value higher than that required for maintaining and activating the biological system. Moreover, the inside of the fish nest space 200 can be purified by increasing the amount of dissolved oxygen.

Note that in order for the upwelling flow 110 to naturally form the swirling flow 120 within the fish nest space 200, the restricted water area 100 must be
An important issue is what size to set.

The size of this limited water area 100 is set depending on the aeration capacity of the air diffuser 10, the water depth H, and various other conditions, but in the embodiment, the size of each side is set to 1.0 to 1.5 H. There is.

In addition, when a plurality of fish nest structures 20 are combined to form a marine farm or the like as in the embodiment, a gap is provided between the lower end of the porous curtain 22 and the seabed, so that fish can body 2
It is preferable to form the fish nest space 200 so that it can move freely within the fish nest space 200.

Furthermore, in addition to the marine farm of the present invention, for example, when purifying a desired water area, it is possible to form the structure so that fish can freely enter and leave the fish nest space 200 with an improved amount of dissolved oxygen from the surrounding water area. , it is also possible to more quickly restore the biological system near the water area.

Further, in the embodiment, a restricted water area 100 is set near the sea surface, and the amount of dissolved oxygen in this water area is increased. Therefore, the natural light that enters from the sea surface promotes photosynthesis in this area, and as a result of the flourishing of photosynthetic plants, the food chain can be stimulated, making it possible to effectively remove pollutants, and also to improve the environment. Since it can breed airborne microorganisms, it can also purify water.

Second Embodiment Next, a second preferred embodiment of the present invention will be described with reference to the drawings.

FIG. 4 shows a preferred example of an artificial reef to which the present invention is applied.

In the artificial fish reef of the embodiment, a plurality of fish nest structures 20 are aligned and arranged on the seabed, and a fish nest space 200 sufficient to secure living space elements for fish is formed within each fish nest structure 20.

FIG. 5 shows a schematic sectional view of the fish nest structure 20, and FIG. 6 shows a schematic explanatory view thereof.

The fish nest structure 20 of the embodiment has a fish nest space 200 separated by a partition wall 14.
The partition wall 14 of the embodiment includes a cylindrical part 30 formed to surround the side of the fish nest space, and a predetermined inclination in the vertical direction above the cylindrical part 30. and a ceiling portion 32 for covering.

The cylindrical portion 30 is formed to have a cylindrical rectangular cross section as shown in FIG. 6, and has a plurality of windows 34 formed therein so that fish can freely enter and exit the cylindrical portion 30.

An air diffuser 10 is provided at the center of the bottom of the fish nest space 200, and by performing an aeration operation, an upwelling flow 110 is formed upward from the bottom of the fish nest space 20. The partition wall 12 surrounding the space 200 forms a flow in which the upwelling flow 110 becomes a swirling flow 120.

Thereby, also with the fish nest structure 20 of this embodiment, the fish nest space 200 can be made into the restricted water area 100, and the amount of dissolved oxygen in this fish nest space 200 can be sufficiently increased.

In the embodiment described above, the partition wall 12 was formed using a porous curtain, but in the embodiment, it is preferable to form it using a normal wall material such as concrete.

Further, when the fish nest space 200 is formed as in the embodiment, it is necessary to release air generated by aeration from the fish nest space. For this purpose, one end of a hose 36 for removing air is attached to the top of the ceiling portion 32, and the other end of this hose 36 is fixedly attached to a float 38 floating above the sea surface.

As a result, excess air generated by aeration can be discharged into the atmosphere through this hose 36.

Further, it is preferable to provide a deodorizing device at a predetermined location of the hose 36, so that even if odor adheres to the air that has passed through the water, it can be reliably deodorized.

In addition, when a fish reef is constructed near the seabed in this way, there is a problem in that photosynthetic plants have difficulty propagating.

In other words, in addition to increasing the amount of dissolved oxygen in the fish nest space 200, it is also necessary to promote the feed effect for fish as a condition for a fish nest, and ensuring food for fish is especially important in highly polluted waters. This is the most difficult challenge in satisfying the above.

The advantage of the artificial fish reef of this example is that in addition to securing the amount of dissolved oxygen, which is the key point for a general fish nest as mentioned above, it also secures the feed effect for such fish and restores the biological system. It's in the point of gaining.

To restore biological systems in contaminated waters, it is necessary to restore the food chain.

The food chain is a cycle consisting of producers, consumers, and reducers as shown below.

(Producer) (Primary consumer) Abasic substances - Photosynthetic plants - Rotifera, Crustacea = (Secondary consumer) Fish → Organic matter → (Reducer) Barteria → And especially What is important is the presence of photosynthetic plants, which are the producers, and the conditions necessary for this photosynthesis (light, carbon dioxide gas, temperature, nutrient bases). Of these, securing light is an absolute requirement in contaminated waters.

Therefore, in this embodiment, a light concentrating device 40 is installed on the sea surface using a float 50, etc., and the sunlight is collected by the light concentrating device 40, and the visible light necessary for growing plants is transmitted to one end of the optical fiber 42. It is input to. This optical fiber 42 transmits light to the fish nest structure 20 and emits the light into the attached algae culture rod 44 and the phytoplankton culture vessel 46 .

The culture rod 44 has a cloudy white liquid-tight structure, and has a cylindrical shape filled with air.

Similarly, the phytoplankton culture vessel 46 has a cloudy white liquid-tight structure and is filled with air.

By irradiating light from the optical fiber 42 to the culture rod 44 and culture vessel 46, the light diffused by the internal air is emitted as relatively gentle light due to the cloudy white color of the rod 44 and culture vessel 46. become. By optimizing the amount of light for photosynthesis of plants, adherent algae can grow on the entire outer surface of each rod 44, and floating phytoplankton can be cultivated on the outer wall of the culture vessel 60. become.

In particular, the attached algae culture rod 44 placed in the living space of fish can attract fish by irradiating it with gentle light, and fish that prefer this type of algae as food are attracted to it. By doing so, it becomes possible to sequentially grow new attached algae.

These plankton and plants act as producers in the above-mentioned plant chain, so they breed zooplankton, which is the primary consumer, and as a result, secure food for fish, which is the secondary consumer. Can be done.

In this way, in this embodiment, even if the water area is heavily polluted, the biological system can be restored by irradiating the water area with light through the optical fiber 42, and especially in places where direct light does not strike, such as on the ocean floor. Remarkable effects can be achieved even in places.

FIG. 7 shows a specific configuration of the light condensing device 40, in which a large number of Fresnel lenses 54 supported by a curved arm 52 are disposed, and the The Fresnel lens 54 is made swingable by a motor (not shown). Further, the fulcrum shaft 52a of the curved arm 52 is rotatable by a motor (not shown), and as a result, the Fresnel lens 54 can be directed in the direction of sunlight irradiation.

One end of the optical fiber 42 (not shown in FIG. 7) is arranged at the light focusing position of each Fresnel lens 54, so that the light focused by the Fresnel lens 54 is incident thereon. Note that the Fresnel lens 54 has a refractive index that differs depending on the wavelength of sunlight when it passes through the lens. The position of one end of the optical fiber 42 is set at a position where visible light rays are focused, and light of other wavelengths, such as ultraviolet rays and infrared rays, is prevented from entering the one end of the optical fiber 42.

As mentioned above, this condensing device 40 has a structure that follows the position of the sun, but its control is performed by calculating the sun's position based on the year, month, day, and time indicated by the built-in clock mechanism, and based on this result. Based on this, the Fresnel lens 54 is moved in the direction of the sun. A solar position detection optical sensor 56 is arranged inside the transparent dome, and when direct sunlight is coming out, this sensor 56 detects the exact position of the sun and interrupts the movement position of the Fresnel lens 54. It's meant to be controlled.

Note that the present invention is not limited to the above embodiments,
Various modifications are possible within the scope of the invention.

For example, in the embodiments described above, the present invention was explained by taking as an example a fish nest structure installed in the ocean such as a bay, but the present invention is not limited to this, and can also be applied to a fish nest structure installed in a lake, river, etc. It goes without saying that it is possible.

Furthermore, the method for improving the amount of dissolved oxygen of the present invention not only improves the amount of dissolved oxygen in fish nest spaces, but also in bays and rivers.

It can also be used to purify polluted water bodies such as lakes, and in particular, by emitting natural light or light source light through an optical fiber, etc., to a restricted water area where the amount of dissolved oxygen has been improved by the method of the present invention. Since it can promote photosynthesis and promote the food chain, it can also effectively remove pollutants and purify water.

Further, in the above embodiment, as the light guided by the optical fiber 42, the one that uses sunlight is superior in that it can utilize natural energy, but the present invention is not limited to this, but the one that uses light from a light source, Alternatively, sunlight and light source light may be switched and used.

[Effects of the Invention] As explained above, according to the present invention, aeration is performed to blow out a gas containing 0□ into a predetermined limited water area, and an upwelling flow from below to upward in the limited water area is It is possible to form a flow that naturally turns into a swirling flow from above to below. Therefore, the amount of dissolved oxygen within the restricted water area can be significantly increased, and the water area can be purified and biological systems can be maintained and activated.

In particular, according to the present invention, it is possible to sufficiently increase the amount of dissolved oxygen in the restricted water area within the fish nest space, and to fully satisfy the living space factors as necessary conditions for the fish nest.

Furthermore, according to the present invention, in addition to the living space element as an essential requirement for a fish nest, by providing light through an optical fiber, when the fish nest space is provided on the seabed or the like where light cannot reach, However, even in highly polluted waters where light cannot reach the water, it is possible to promote photosynthesis, increase the effectiveness of feed through the flourishing of plants, and further restore the biological system to start the food chain. It can also promote water purification.

[Brief explanation of the drawing]

1 to 3 show a preferred first embodiment of the present invention, FIG. 1 is a schematic side sectional view of the fish nest structure, and FIG. 2 is the fish nest structure of FIG. 1. 3 is a schematic illustration of the surface of the fish nest structure shown in FIG. 1, and FIGS. 4 to 7 are illustrations of a second preferred embodiment of the present invention. An example is shown. Figure 4 is an explanatory diagram of an artificial fish reef formed on the sea floor using a plurality of fish nest structures, Figure 5 is a schematic side cross-sectional diagram of the fish nest structure, and Figure 6 is an explanatory diagram of an artificial fish reef formed on the sea floor using a plurality of fish nest structures. FIG. 7 is an explanatory diagram of a light condensing device used in the fish nest structure shown in FIG. 5; FIG. 8 is an explanatory diagram showing an example of a conventional method for improving the amount of dissolved oxygen. It is. DESCRIPTION OF SYMBOLS 10... Air diffuser, 14... Partition wall, 20... Fish nest structure, 22... Porous curtain, 30... Cylindrical part, 32... Ceiling part, 42... Optical fiber 44... Adhesive algae culture rod, 46... Phytoplankton culture device, 100... Limited water area, 110... Upwelling flow, 120... swirling flow,
200...Fish nest space.

Claims (8)

[Claims] (1) Use an aeration device to blow out gas containing at least O_2 to form an upwelling flow from below to above a predetermined limited water area, and a partition wall around the limited water area to prevent the upwelling flow from dispersing. To increase the amount of dissolved oxygen in a confined water area by creating a natural swirling flow from above to below by using the upward force of the upwelling flow. A method for improving the amount of dissolved oxygen in a confined water area. (2) In claim (1), the limited water area is set near the water surface, and the partition wall for preventing upwelling flow diffusion includes a permeable porous curtain installed to surround the limited water area. A method for improving the amount of dissolved oxygen in a confined water area, characterized by being formed using the method. (3) an aeration device that blows out gas containing at least O_2 toward the restricted water area of the fish nest space to form an upwelling flow from below; A partition wall for preventing the upwelling flow from dispersing, which uses the upward force to naturally turn the upwelling flow into a swirling flow from above to below. A fish nest structure characterized by increasing. (4) In claim (3), the limited water area is set near the water surface of the water area, and the partition wall for preventing upwelling diffusion is a permeable porous wall constructed to surround the limited water area. A fish nest structure characterized by being formed using a curtain. (5) In claim (3), the limited water area is set in a deep part of the water area, and the partition wall includes: a cylindrical part formed to surround a side of the limited water area; and an upper part of the cylindrical part. What is claimed is: 1. A fish nest structure comprising: a ceiling portion that is covered with a predetermined slope in the vertical direction; and an air venting hose is provided between the ceiling portion and the water surface. (6) In any one of claims (3) to (5), an optical fiber is provided that receives natural light or light source light from one end and emits the light from the other end into the restricted water area of the fish nest space. A fish nest structure characterized by: (7) The fish nest structure according to claim (6), wherein the limited water area is provided with a phytoplankton incubator into which the other end of the optical fiber is inserted. (8) A fish nest structure according to any one of claims (5) to (7), characterized in that the air vent hose is provided with a deodorizing device.