JP6973832B1 - Aquatic animal farming equipment and farming methods - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a aquaculture apparatus which efficiently removes solid organic matter and the like, reduces hedroization of the organic matter and the like, and easily adjusts the dissolved oxygen concentration in the cultivation of aquatic animals using a sand layer. SOLUTION: A culture tank (10) for accommodating aquaculture water (11), a sand layer (12) arranged at the bottom of the culture tank (10), and / or along the sandy ground of the sand layer (12). , The bubble supply means (22) for sending bubbles toward the sandy ground of the sand layer (12) and the surface layer of the aquaculture water (11) were accompanied by the bubbles supplied by the bubble supply means (22) and surfaced. Aquaculture equipment for aquatic animals (100) that removes organic matter. [Selection diagram] Fig. 1

Description

The present invention relates to an aquatic animal aquaculture apparatus and aquaculture method. In particular, the present invention relates to aquaculture equipment suitable for aquaculture using a sand layer such as shrimp.

Various fish and shellfish are cultivated for mass production, stable supply, and high quality of foodstuffs. Aquaculture conditions differ depending on the ecology of fish and shellfish, and in general, aquaculture is carried out according to the conditions in which each fish and shellfish naturally inhabits. For example, prawns are nocturnal and rest in a sand layer depending on the time of day, so it is necessary to provide a sand layer or the like in the aquaculture site when culturing. The following documents and the like are disclosed for aquaculture using a sand layer.

Patent Document 1 has a aquaculture tank and water supply pipes arranged at regular intervals at the bottom of the aquaculture tank, and the water supply pipes are characterized by having spouts on the side surfaces at a constant pitch. Discloses aquaculture equipment for aquatic animals.

Patent Document 2 describes a circular water tank having a circular shape with a sand bed at the bottom and an annular septic tank for purifying seawater along the peripheral wall, and an upper peripheral edge of a drain pipe provided at the center of the bottom. In an aquaculture device having a first circulation mechanism for circulating seawater in one direction and a second circulation mechanism for circulating seawater near the peripheral wall of the circular water tank in the same direction, an opening in the drain pipe and the bottom thereof. Disclosed is an aquaculture animal farming apparatus characterized in that each of the seawater supply pipes to be connected to the septic tank is connected to the septic tank.

Patent Document 3 discloses a prawn aquaculture aquarium characterized in that a sand layer is provided at the bottom of the aquarium and a seawater outlet pipe having a large number of outlets and continuously supplying fresh seawater is provided in the sand layer. doing.

Japanese Unexamined Patent Publication No. 2017-085903 Japanese Unexamined Patent Publication No. 2002-360110 Japanese Unexamined Patent Publication No. 61-293325

One of the aquaculture targets that use the sand layer is prawns. Prawns are nocturnal and sneak into the sand during the day to rest. Also, at night, they go out on the sand or in the water to feed. For this reason, sand is required for tiger prawn farming. The tiger prawn aquaculture technology takes seawater into a large-area aquaculture tank, also known as a semi-embankment or a full-embankment. It also regulates the photosynthesis of diatoms and the dissolved oxygen concentration in aeration with a water wheel. Such traditional traditional prawn farming has the following problems.

(1) Maintaining the amount of dissolved oxygen. A large amount of aeration with a water wheel is required to maintain the amount of dissolved oxygen. In particular, it is necessary to prevent oxygen deficiency due to oxygen consumption, which increases at night when prawns are active. However, the conventional technology requires a huge power cost for aeration by a large water turbine, and the conventional technology cannot maintain the dissolved oxygen amount evenly to the bottom layer.
(2) Accumulation of solid organic matter and hedro. Solid organic matter such as feces, molting shells, residual food and diatoms are deposited on the sand layer, which is the growing environment for prawns. The deposited organic matter is decomposed by bacteria and becomes hedro. At this time, oxygen is also consumed, so if there is an area where oxygen is not supplied, oxygen is insufficient and an anaerobic environment is created, so that the nitrification of highly toxic ammonia does not proceed. It also generates harmful substances such as hydrogen sulfide. In particular, it is difficult to remove solid organic substances mixed in the sand layer.
(3) Difficult to remove from the sand layer. A great deal of human effort is required to net or dive to manually remove hedro to remove solid organic matter and hedro deposited on the sand layer. In addition, since it is mixed with the sand layer and the visibility is poor, there is a part that has to rely on the experience and intuition of experts, and it is difficult to manage efficiently.

In order to prevent the generation of harmful substances due to the accumulation of hedro in these sand layers, some aquaculture methods for removing organic substances from the sand layers have been proposed as in Patent Documents 1 to 3. These can prevent the stagnation of organic matter in the sand layer due to the structure in which the organic matter is flushed upward by a water stream. The organic matter released into the water is discharged from the drainage port on the bottom of the aquaculture tank through a filter. Therefore, it is not possible to prevent the accumulation of organic substances on the filter.

Under such circumstances, the present invention provides a culture device and aquaculture method that efficiently remove solid organic matter and the like, reduce the formation of organic matter and the like, and easily adjust the dissolved oxygen concentration when culturing aquatic animals using a sand layer. The purpose is to do.

As a result of diligent research to solve the above problems, the present inventor has found that the following invention meets the above object, and has arrived at the present invention. That is, the present invention relates to the following invention.

<1> Aquaculture tanks containing aquaculture water, a sand layer arranged at the bottom of the aquaculture tank, and bubbles containing oxygen along the sandy ground of the sandy layer and / or toward the sandy ground of the sandy layer. An aquatic animal aquaculture device that removes organic substances that have floated along with the bubbles supplied by the bubble supply means on the surface layer of the aquaculture water.
<2> The aquaculture apparatus according to <1>, which has a foreign matter removing means for removing the floating organic matter on the surface layer of the aquaculture water.
<3> The bubble supply means can supply two or more types of bubbles selected from the group consisting of the first bubble to the third bubble having different bubble rise rates.
The first bubble has a bubble rising rate of 50 mm / sec or less, and has a bubble rising rate of 50 mm / sec or less.
The second bubble has a bubble rising rate of 5 to 500 mm / sec, and the bubble rising rate is higher than that of the first bubble.
The aquaculture apparatus according to <1> or <2>, wherein the third bubble has a bubble rising rate of 50 mm / sec or more and a bubble rising rate higher than that of the second bubble.
<4> The culture apparatus according to any one of <1> to <3>, which has a switching means for switching the bubbles supplied by the bubble supply means according to the time zone and / or the oxygen concentration of the culture water.
<5> Any of the above <1> to <4>, wherein a plurality of the bubble supply means are arranged and the supply directions are arranged so as to have different supply directions when the aquaculture tank is viewed in a plan view. The aquaculture equipment described in the crab.
<6> The aquaculture apparatus according to any one of <1> to <5>, wherein the aquatic animal is prawn.
<7> Aquaculture tanks accommodating aquaculture water, a sand layer arranged at the bottom of the aquaculture tank, and air bubbles are sent out along the sandy ground of the sandy layer and / or toward the sandy ground of the sandy layer. It is a method of aquatic animal aquaculture using aquaculture apparatus having a bubble supply means, and has a bubble supply step of supplying bubbles by the bubble supply means and a removal step of removing organic substances that have floated along with the bubbles. Aquaculture method for aquatic animals.

According to the aquaculture apparatus and aquaculture method of the present invention, when aquatic animals are cultivated using a sand layer, solid organic matter and the like can be efficiently removed, hedroization of the organic matter and the like can be reduced, and the dissolved oxygen concentration can be easily adjusted. can.

It is a schematic diagram which looked at the front view of the aquaculture apparatus which concerns on 1st Embodiment of this invention. It is a schematic diagram which looked at the plan view of the aquaculture apparatus which concerns on 1st Embodiment of this invention. It is a schematic diagram which looked at the foreign matter removing means used for the culture apparatus of this invention. It is the schematic which looked at the front view of the foreign matter removing means used for the culture apparatus of this invention. It is a schematic diagram which made the foreign matter removing means used for the culture apparatus of this invention a plan view. It is a schematic diagram which looked at the front view of the aquaculture apparatus which concerns on the 2nd Embodiment of this invention. It is a schematic diagram which looked at the front view of the aquaculture apparatus which concerns on the 3rd Embodiment of this invention. It is a flow chart which shows an example of the culture method of this invention. It is a flow figure which shows another example of the culture method of this invention. It is a figure for demonstrating the control of the culture method of this invention. It is an image for showing the outline of the bubble to supply in this invention.

Hereinafter, embodiments of the present invention will be described in detail, but the description of the constituent elements described below is an example (representative example) of the embodiments of the present invention, and the present invention is described below unless the gist thereof is changed. It is not limited to the contents of. In addition, when the expression "~" is used in this specification, it is used as an expression including numerical values before and after it.

[Aquaculture apparatus of the present invention]
The aquaculture apparatus of the present invention comprises a aquaculture tank containing aquaculture water, a sand layer arranged at the bottom of the aquaculture tank, and along the sandy ground of the sandy layer and / or toward the sandy ground of the sandy layer. On the bubble supply means for sending out the bubbles and the surface layer of the aquaculture water, the organic matter floating along with the bubbles supplied by the bubble supply means is removed.

[Culturing method of the present invention]
The aquaculture method of the present invention comprises a aquaculture tank containing aquaculture water, a sand layer arranged at the bottom of the aquaculture tank, along the sandy ground of the sandy layer, and / or toward the sandy ground of the sandy layer. It is a method of aquatic animal aquaculture using an aquaculture device having a bubble supply means for sending bubbles, a bubble supply step of supplying bubbles by the bubble supply means, and removal of organic substances that have floated along with the bubbles. Has a process.

According to the aquaculture apparatus and aquaculture method of the present invention, when aquatic animals are cultivated using a sand layer, it is possible to efficiently remove solid organic matter and the like, reduce the formation of organic matter and the like, and maintain an appropriate dissolved oxygen concentration. can. In addition, in the present application, the aquaculture method of the present invention can be carried out by the aquaculture apparatus of the present invention, and the configurations corresponding to each can be mutually used in the present application.

The present invention keeps the entire aquaculture tank, including the sand layer and aquaculture seawater, which are the habitats of aquatic animals such as shellfish, always clean while suppressing running costs such as manpower and electricity costs, and the quality and production of aquatic animal cultivation. Provide aquaculture equipment that can increase sex.

[First Embodiment]
FIG. 1 is a schematic view of the aquaculture apparatus according to the first embodiment of the present invention as a front view. Further, FIG. 2 is a schematic view of the aquaculture apparatus according to the first embodiment of the present invention in a plan view. The aquaculture device 100 includes a aquaculture tank 10 for accommodating aquaculture water 11, a sand layer 12, and a bubble supply means 22. It also has foreign matter removing means 30, water supply means 50, and the like.

[Aquaculture tank 10]
The aquaculture tank 10 accommodates the aquaculture water 11. The size of the aquaculture tank 10 is set in consideration of the size of the aquatic animals to be cultivated, the aquaculture density, and the like. According to the present invention, the entire inside of the aquaculture tank can be efficiently used for aquaculture. Therefore, even if the whole aquaculture tank is generally cultivated with a large cage such as a shrimp, one side of the aquaculture tank is one side. A relatively small-scale aquaculture tank having a diameter of about 5 to 20 m and a diameter of about 5 to 20 m can be used in the case of a columnar shape or the like. It may be larger than these.

The shape of the aquaculture tank 10 is not particularly limited as long as it can be cultivated, such as a polygonal columnar shape, a columnar shape, and a weight stand shape. Use a columnar outer shape that becomes a circle when viewed in a plan view so that retention does not easily occur in a part of the aquaculture tank 10, or a truncated cone shape such that a sand layer or the like is easily collected on the bottom surface. be able to. The aquaculture tank 10 of the aquaculture apparatus 100 shown in FIG. 1 is a columnar one.

The aquaculture tank 10 can be made of concrete, fiber reinforced plastic (FRP), polypropylene resin, or the like in a world having sufficient strength.

[Aquaculture water 11]
The aquaculture water 11 is used according to the aquatic animals to be cultivated. For example, seawater, freshwater, brackish water in the middle of these can be used. These may be artificially adjusted or may be taken from a river or the sea.

[Aquatic animals]
The aquaculture device 100 is for cultivating aquatic animals. The aquatic animals to be cultivated can be edible fish and shellfish that require a sand layer 12. For example, it can be crustacean or shellfish. As crustaceans, shrimp and mantis shrimp are ecology with submersible nature. Examples of shellfish include clams and fulvia mutica. Among them, prawns such as prawns, which have an ecology of resting in the sand and are widely cultivated for food, are preferable.

[Sand layer 12]
The sand layer 12 is a layer of sand arranged on the bottom side of the aquaculture tank 10. As the sand used for the sand layer 12, those suitable for the ecology of aquatic animals can be appropriately used. Although sea sand is generally used, it is preferable to use coarse sand having a low density such as anthracite so that aquatic animals can easily dive and solid organic matter can easily move. The thickness of the sand layer 12 is appropriately adjusted depending on the type of aquatic animal, for example, in the case of prawns, it can be about 5 to 20 cm.

[Bubble supply means 22]
The bubble supply means 22 sends out bubbles along the sandy ground of the sand layer 12. Alternatively, air bubbles are sent toward the sandy ground of the sand layer 12. The bubble supply means 22 may send out bubbles in both the direction along the sandy ground and the direction toward the sandy ground. At this time, a plurality of bubble supply means 22 may be arranged and sent out in both the direction along the sandy ground and the direction toward the sandy ground, or the single bubble supply means 22 may send bubbles in a plurality of directions. May be sent in both directions by sending.

The bubble supply means 22 sucks the aquaculture water 11 from the water supply pipe 21 by the circulation pump 23, and supplies the aquaculture water into the culture tank 10 as water containing bubbles through the water supply pipe 20 and the bubble supply means 22. As the bubble supply means 22, one that can variably control the bubble diameter can be used. Water containing bubbles may be referred to as bubble water.

The aquaculture apparatus and the like of the present invention utilize the power of air to discharge solid organic matter around the sand layer 12. For this purpose, bubble water containing bubbles is sent out from the bubble supply means provided on the surface layer portion or the lower portion of the sand layer. Due to the bubble separation effect of bubbles, solid organic matter is released upward from the sand layer, and the organic matter is pushed up to the surface of the water without staying in the water.

The bubbles supplied by the bubble supply means 22 are bubbles containing oxygen. In supplying such bubbles, the gas used is, for example, air, high-purity oxygen, or a mixed gas in which oxygen is appropriately mixed with air or another gas to adjust the oxygen concentration. Can be done. The oxygen concentration of the gas can be 20 to 100%.

It is preferable that the bubble supply means 22 can supply two or more types of bubbles having different bubble rise rates. The bubbles are preferably those that supply two or more kinds of bubbles selected from the group consisting of the following first bubbles to third bubbles. The bubble rising rate shall be in seawater at 25 ° C. Based on the Stokes equation, assuming seawater at 25 ° C, the time it takes for bubbles generated at the bottom of the water at a depth of 1 m to reach the water surface is about 10 minutes when the bubble diameter is 50 μm (rising speed: about). 1.5 mm / sec), about 2.7 minutes when the bubble diameter is 100 μm (rising speed: about 6.1 mm / sec), about 1.6 seconds when the bubble diameter is 1 mm (rising speed: about 611 mm / sec) Seconds).

The first bubble has a bubble rising rate of 50 mm / sec or less. The lower limit of the bubble rising rate does not have to be set in particular, and nanobubbles, which are also called ultrafine bubbles, may be substantially 0 mm / sec or a theoretically negative value. Such first bubbles are useful for improving the dissolved oxygen concentration, and positively supply them during times when oxygen consumption is active.

The second bubble has a bubble rising rate of 5 to 500 mm / sec and a bubble rising rate higher than that of the first bubble. The second bubble is suitable for adsorbing or ascending an organic substance because it has a relatively large surface area with respect to the capacity of the gas in addition to improving the dissolved oxygen concentration. Therefore, it is positively supplied during the time when organic matter is discharged.

The third bubble has a bubble rising rate of 50 mm / sec or more and a bubble rising rate higher than that of the second bubble. The third bubble may not have an upper limit, but may be, for example, 5 m / sec or less, 2 m / sec or less, 1 m / sec or less, or the like. The third bubble is a bubble suitable for adsorbing and rising organic matter, and is also suitable for creating a rising water flow from the bottom side of the cultured water 11 to the water surface side and a convection facing the outer periphery on the water surface. Along with this rising water flow and the convection toward the outer circumference on the water surface, the bubbles adsorbing the organic matter are moved to the water surface and moved to the outer circumference of the aquaculture tank 10. Therefore, the organic matter that has surfaced after the time zone for discharging the organic matter is positively supplied from the foreign matter removing means 30 to the outside of the aquaculture tank 10.

These first to third bubbles are controlled so that they can be switched according to the time zone, the dissolved oxygen concentration measured by a sensor, the activity state of aquatic animals captured by a camera, etc. be able to. In the control, the operation conditions of the same bubble supply means 22 may be switched, or a plurality of bubble supply means 22 suitable for each bubble may be arranged and supplied.

In addition, in order to maintain the dissolved oxygen amount at an appropriate value by increasing the oxygen dissolving effect by making the fine bubble diameter extremely small during the time when the organism actively feeds and feeds, or during the time when the dehulling activity is performed. It is considered that the oxygen consumption required for the organism to carry out feeding activity and dehulling activity should be sufficient as long as it can be maintained. As a reference, it has been said that the required oxygen consumption for prawns is 77 to 135 mL / kg / hour at rest and about three times that during activity (Reference: National Coastal Fisheries Promotion and Development Association (1993)). Environmental conditions of aquatic organisms, guidelines for designing facilities for coastal fishing ground development projects).

In the demonstration experiment of the aquaculture apparatus according to the present invention, DO (Dissolved Oxygen) may change to a relatively low value. In addition, the activity of prawns may be less than that of conventional aquaculture. This is because the aquaculture density is high and oxygen consumption is high, so there is no extra activity to keep the balance between activity and oxygen concentration decrease, or there is no need to search for food, so no extra activity is done. Conceivable. In addition, even though these tendencies are observed, growth is fast and molting occurs frequently. In other words, it is considered that nutrition is used for growth because there is less need for activities such as searching for food. Therefore, it is considered that growth can be accelerated by suppressing power consumption and maintaining an active oxygen amount without maintaining an excessively high dissolved oxygen concentration.

Bubbles can be generated, for example, by the circulation pump 23 and the bubble generation nozzle. The size of the bubbles is adjusted by controlling the supply amount of these bubble generation nozzles and the like. Therefore, the rising rate of bubbles in seawater at 25 ° C. may be grasped in advance, and the setting condition may be regarded as the rising rate of bubbles during aquaculture.

For the bubble rising rate, the distance from the bubble supply means 22 to the water surface of the aquaculture water 11 is set to D, and the image of the bubbles generated from the bubble supply means 22 and reaching the water surface of the aquaculture water 11 is acquired, and the bubbles generated at a certain point in time T0. It can be derived by measuring the time T1 at which the water reaches the water surface of the cultured water 11 and calculating with D / (T1-T0). When the bubble generated from the bubble supply means 22 is so small that it cannot be recognized as an image, it can be identified as a bubble having a bubble rising speed of 50 mm / sec or less. When the bubble generated from the bubble supply means 22 has a size that can be recognized as an image, 100 bubbles generated at the time of T0 are randomly captured, and the ascending speed of these is measured and the average value is obtained. Thereby, the size of the bubble supplied from the nozzle can be derived.

The bubble supply means 22 does not need to be constantly operated during aquaculture. It may operate intensively during the time period when the activity of aquatic animals becomes active and there is a concern that the dissolved oxygen decreases, or the time period when feces, residual food, and molting shells occur. Alternatively, a sensor for the dissolved oxygen concentration as an index thereof may be attached to have a control means for controlling the presence or absence of operation in conjunction with the measured value.

The bubble water discharged to the sand layer 12 diffuses the surface layer portion of the sand layer 12, adsorbs the organic matter in the vicinity of the sand layer 12, pushes it up to the aquaculture water 11, and further reaches the water surface of the aquaculture water 11. Bubbles adsorbing organic matter that have reached the water surface of the aquaculture water 11 float on the water surface in the form of bubbles and are discharged to the outside. When excluding it to the outside, it may overflow from the container of the aquaculture tank 10, or a configuration for removing it may be provided in the aquaculture tank.

[Organic matter (foreign matter)]
Aquaculture of aquatic animals produces feces, molting shells, residual food, and solid organic matter such as diatoms. They can be a source of nutrients for microorganisms, unintended metabolism of microorganisms, and accumulation without decomposition, which can cause water pollution. In addition, it may be easily mixed with the sand layer, and if it gets into the gaps of the sand layer, it becomes difficult to supply dissolved oxygen, and it may be anaerobically treated to generate harmful components for aquatic animals, or it may become hedro and worsen. be. In the present invention, these solid organic substances and the like are removed by being accompanied by bubbles. It should be noted that these solid organic substances are not limited to those that are completely solid, but also include those that have viscosity, and may be referred to as foreign substances.

[Foreign matter removing means 30]
The foreign matter removing means 30 is arranged so that the intake port is arranged near the surface layer of the aquaculture water 11 of the aquaculture tank 10. In the aquaculture apparatus 100, air bubbles accompanied by organic matter and the like gather on the surface layer of the water surface of the aquaculture water 10, enter the intake port by water flow or convection, and can be discharged to the outside of the aquaculture tank 10 via the pipe 31.

[Water intake structure of foreign matter removing means 30]
FIG. 3 is a perspective view of the foreign matter removing means used in the aquaculture apparatus of the present invention. FIG. 3 shows the structure near the intake. FIG. 3A shows a comb tooth 301 provided on the upper part of the water intake. Further, FIG. 3B shows a net 302 provided on the upper part of the intake. By providing these structures, it is possible to prevent aquatic animals and the like contained in the cultured water 11 that are not excluded from being washed away. The foreign matter entrained by the air bubbles is discharged from the aquaculture tank 10 through the pipe 31 through the gaps between the comb teeth 301 and the net 302.

FIG. 4 is a schematic view of the foreign matter removing means used in the aquaculture apparatus of the present invention as a front view. FIG. 4A shows a state in which the intake port of the foreign matter removing means 30 is arranged on the water surface 111 of the aquaculture water 11. FIG. 4B has a structure in which the float 303 is arranged near the intake and the pipe is a flexible pipe 311. As a result, even if the water level changes, the intake port of the foreign matter removing means 30 will be near the water surface 111 of the aquaculture water 11. The pipe 310 and the flexible pipe 311 are piped to the outside of the wall 101 of the aquaculture tank so as to serve as a discharge port. Further, by using the flexible pipe 311, it becomes easy to move the foreign matter removing means 30 to the region where the bubble-like unnecessary organic matter adhering to the bubbles gathers due to the water flow or the wind direction, and the foreign matter removing effect is further enhanced.

FIG. 5 is a schematic view of the foreign matter removing means used in the aquaculture apparatus of the present invention in a plan view. The foreign matter removing means 30 shown in FIG. 5 is arranged between the wall 101 and the partition 33 arranged in the vicinity of the wall 101. The partition 33 is arranged near the water surface, and can be opened from the middle layer to the bottom layer so that the aquaculture water 11 can circulate. The partition 33 may be configured such that a water flow is generated in the circulation of the aquaculture water 11 so that the wall 101 and the partition 33 receive the water flow in a concave shape with respect to the traveling direction of the water flow. As a result, bubbles accompanying organic substances and the like floating on the water surface move by the water flow, gather so as to be captured by the concave portion with respect to the water flow, and are efficiently discharged from the water intake of the foreign matter removing means 30.

In this way, a swirling flow may be created in the aquaculture tank in order to promote the discharge of bubbles accompanied by organic matter, and a foreign matter removing means may be provided on the peripheral wall portion of the aquaculture aquarium. Further, foreign matter removing means may be scattered before the foamy organic matter moves depending on the wind direction or the like. Further, the water level in the aquarium may be raised by supplying water from the outside.

[Drainage port 40]
The drainage port 40 is an opening for drainage arranged at the bottom of the aquaculture tank 10. The drainage port 40 is used when draining water after aquaculture. The drainage filter 41 is installed near the intake port of the drainage port 40 so that the sand of the sand layer 12 and aquatic animals do not flow out.

[Water supply means 50]
The water supply means 50 is a means for supplying aquaculture water into the aquaculture tank 10. When the aquaculture water 11 in the aquaculture tank 10 is in a good state, the water supply means 50 can be stopped and the aquaculture water 11 in the aquaculture tank 10 can be circulated and used. When the aquaculture water 11 is in a deteriorated state, the water in the aquaculture tank 10 can be improved by supplying water from the outside via the water supply means 50. Further, depending on the amount of water supplied, the water level can be adjusted so that bubbles accompanying organic substances and the like floating on the water surface are discharged from the water intake of the foreign matter removing means 30.

[Water purification treatment]
In the aquaculture apparatus of the present invention, it is also possible to use aquaculture water to which a microorganism such as Bacillus is added after removing viruses, diatoms and the like by using a water purification means such as a UV sterilizer. As a result, it is possible to prevent diseases, it becomes easier to maintain the water quality, the transparency increases, and it becomes easier to grasp the state inside the tank.

[Second embodiment]
FIG. 6 is a schematic view of the aquaculture apparatus according to the second embodiment of the present invention in a plan view. The aquaculture device 1001 is a modified example of the aquaculture device 100 according to the first embodiment. The aquaculture device 1001 is a device in which a plurality of bubble supply devices 22 are arranged. Further, these plurality of bubble supply devices 22 are arranged so that the supply directions are different when the aquaculture tank is viewed in a plan view. By supplying bubbles and bubble water from the plurality of bubble supply devices 22 in a plurality of different directions, the place where the bubbles are supplied becomes wide and the water flow becomes larger. The number of bubble supply devices 22 can be two or more or three or more. If it is excessively arranged, the labor required for preparing the equipment and the electric power consumed by the operation become excessive. Therefore, the number may be 20 or less, 15 or less, or 10 or less.

For example, when viewed in a plan view, the bubble water supply means 22 is oriented at 5 to 60 ° with respect to the angle toward the center of the aquaculture tank 10 when the angle toward the center of the aquaculture tank 10 is 0 °. Can be placed in. This angle may be 10 to 50 ° or 30 to 45 °.

In the aquaculture device 1001 of FIG. 6, four bubble supply devices 22 are arranged, and are arranged near the wall of the aquaculture tank 10 and near the apex of the inscribed square of the circle. The bubble supply device 22 is arranged to send bubble water toward the adjacent bubble supply device 22 arranged in a counterclockwise direction. With this arrangement, bubble water is sent out at an angle of 45 ° with respect to the angle toward the center of the aquaculture tank 10.

[Third embodiment]
FIG. 7 is a schematic view of the aquaculture apparatus according to the third embodiment of the present invention as a front view. The aquaculture device 1002 is a modified example of the aquaculture device 100 according to the first embodiment. The aquaculture apparatus 1002 arranges the filter 13 at the bottom of the aquaculture tank 10. The filter 13 is a mesh filter in which the sand of the sand layer 12 does not easily leak out. By providing the sand layer 12 on the filter 13, the lower part of the filter 13 has a double bottom-like structure without sand.

In the lower layer of the filter 13, a plurality of bubble supply devices 221 for supplying bubble water in a direction toward the sand layer 12 are arranged. With such a structure, it is possible to prevent the solid organic matter mixed in the sand layer 12 from being clogged and to be accompanied by bubbles and removed. This is particularly effective in preventing clogging or the like in the vicinity of the sand layer 12 to prevent anaerobic treatment from occurring and preventing hedro formation or the like.

[Aquaculture method]
FIG. 8 is a flow chart showing an example of the aquaculture method of the present invention. In the method of cultivating aquatic animals using an aquaculture device, first, step S1 which is a bubble supply step of supplying bubbles by a bubble supply means is performed during aquaculture. In addition, step S2, which is a removal step of removing the organic matter that has floated along with the bubbles, is performed. These are carried out continuously and until the aquaculture is completed. Step S3 for determining whether the aquaculture is completed is performed, and when the aquaculture is completed, the supply of bubbles and the like is terminated. Steps S1 and S2 are repeated until the aquaculture is completed. The step S1 for supplying air bubbles may not be performed all the time, and may be adjusted depending on the time zone and the situation in the water tank.

FIG. 9 is a flow chart showing another example of the aquaculture method of the present invention. This flow first performs step S11 to supply a first bubble in order to improve the dissolved oxygen of the aquaculture water during the aquaculture. It is determined in step S21 whether the predetermined time has elapsed. When the predetermined time has elapsed, step S31 for supplying the third bubble is performed. Further, even if the judgment in step S21 is before the lapse of a predetermined time, it is determined in step S22 whether the activity of the aquatic animal has subsided and the oxygen consumption has decreased. When the oxygen consumption is reduced, step S31 for supplying the third bubble is performed. If it is before the lapse of a predetermined time and oxygen consumption is active, the first bubble is supplied until the predetermined time elapses. If management by time zone is sufficient, step S22 may be omitted. Alternatively, step S21 may be omitted and switching may be performed in step S22.

As described above, when the organic substance is positively removed depending on the time zone or the like, step S31 for supplying the third bubble is performed. Next, step S41 is performed in which the foreign matter is removed by being accompanied by the third bubble. It is determined in step S51 whether the predetermined time has elapsed, and the third bubble is supplied until the predetermined time has elapsed. When the step S51 is performed for a predetermined time, the step S61 for determining whether the aquaculture is completed is performed, and if not, the process returns to the step for performing the step S11. When the aquaculture in the aquaculture device is completed, it ends.

FIG. 10 is a diagram for explaining the control of the aquaculture method of the present invention. Here, a setting assuming that the first bubble, the second bubble, and the third bubble are supplied will be described. When breeding nocturnal aquatic animals such as prawns, it is considered that they start feeding at night, and after the feeding is completed, they are excreted and molted due to digestion, and are resting during the day.

In line with this ecology, from 18:00 in the evening to 24:00 (0:00) in the middle of the night, active oxygen consumption is expected, so the first bubble with a small bubble diameter is supplied. Next, from 0:00 to 6:00, when feeding and the like are settled and excretion and molting are assumed, organic matter and the like are adsorbed and raised to supply a second bubble having a slightly large bubble diameter. Next, during the daytime from 6:00 to 18:00, when the prawns are resting and oxygen consumption is considered to be low, a third bubble having a large bubble diameter is supplied to remove organic matter and the like. The prawns are cultivated for several months from the state of juvenile prawns to reach the shipping size. During this period, the conditions such as operating time and frequency are reviewed as appropriate and the tiger prawns are cultivated repeatedly.

For this purpose, it is possible to have a switching means for switching the bubbles supplied by the bubble supply means according to the time zone and / or the oxygen concentration of the aquaculture water.

FIG. 11 is an image for showing an outline of the bubbles supplied in the present invention. The aquaculture tank that supplies these bubbles contains prawn droppings and peeled skin.

The left side of FIG. 11 is a state in which an extremely small size bubble corresponding to the first bubble is supplied. With such bubbles, the bubbles hardly rise. The center of FIG. 11 is a state in which a bubble having a minute size corresponding to the second bubble is supplied. In such bubbles, the bubbles slowly rise, and since the surface area of the bubbles is large, they are accompanied so as to positively adsorb organic substances and the like. The right side of FIG. 11 is a state in which a small-sized bubble corresponding to the third bubble is supplied. In such bubbles, the ascending rate of organic matter is also improved, and convection of water on the water surface is strongly generated.

A large electricity bill is required for water exchange by a pump to remove organic matter and the like in the entire embankment, which is a conventional technique. However, the effect of pollutant removal is not sufficient. In addition, after the completion of aquaculture, it is also necessary to completely drain the breeding seawater and dig up the sand layer using heavy machinery to purify the seedlings before the next seedlings are thrown in. In addition, sand cannot maintain the bottom sediment suitable for aquaculture unless it is replaced in large quantities on a regular basis, and its cost is also a factor that puts pressure on management.

In addition, with the conventional aquaculture technology, it is difficult to grasp the habitat of the tiger prawns that are being cultivated, wasteful feeding occurs, and the yield of aquaculture tends to decrease. In addition, if excessive serving is performed, the sediment environment of the cage will gradually deteriorate, and the area where prawns can live will be further invaded, and cannibalism may occur without maintaining an appropriate density.

In addition, in the conventional technique, the aquaculture period differs depending on the region, and the period is limited. This is because a large amount of seawater is required due to the large size of the cage, and the only means of maintaining an appropriate temperature at which prawns can grow is to replace the seawater, which inevitably depends on the surrounding seawater temperature. In recent years, the seawater temperature has been on the rise due to the effects of global warming, and it has become more difficult to maintain an appropriate water temperature at which prawns can grow.

In addition, it is difficult to grasp the inventory amount in the cage with the conventional technology. Due to the large size of the cage and the environment in which diatoms spring, the number of prawns inhabiting the cage cannot be determined. In addition, in order to maintain the amount of dissolved oxygen in the Ikes seawater, aeration by multiple large water turbines is required, which requires a high electricity bill. This is also affected by the fact that oxygen supply by photosynthesis of diatoms and environmental adjustment by diatoms were considered necessary. However, when diatoms grow, diatoms do not photosynthesize at night and consume oxygen at the same time as nocturnal prawns. It is also considered to be a cause of deterioration in visibility.

As described above, the conventional technique requires a great deal of human labor and cost in order to maintain the inner sediment of the cage in a suitable environment. From the viewpoint of maintaining an aerobic environment, it is necessary to supply oxygen to the sand layer in order to prevent it from becoming heddle, and due to the vast ikesu, the equipment load is heavy and electricity costs are high. From the viewpoint of removing pollutants, since the pollutants are in the sand layer, it is necessary to remove them manually by netting or diving from the ship.

In addition, the prior art also has the following problems. Waste of feeding occurs. Although prawns cannot live in areas where the aquaculture environment has deteriorated, it is not possible to grasp the areas where the environment has deteriorated from the surface of the water. Along with waste, a vicious cycle is created in which the accumulated residual food becomes more heddle.

Aquaculture yield does not increase. Deterioration of the aquaculture environment caused by organic matter causes the area where tiger prawns can live becomes narrower, and the relative inadequate feeding amount reduces the growth of tiger prawns, resulting in lower yields due to cannibalism.

The aquaculture apparatus and aquaculture method according to the present invention can solve these problems of the prior art, and can contribute to the improvement of productivity, the improvement of aquaculture quality, and the improvement of yield.

According to the present invention, the entire aquaculture environment can be kept clean. In addition, it is possible to maintain a wide area where aquatic animals can live.

Further, according to the present invention, the supplied bubbles also have the effect of increasing the dissolved oxygen in the water. By releasing air bubbles from around the sand layer, the sand layer can always be kept in an aerobic environment. Then, even if an organic substance is trapped in the sand layer, it is possible to prevent the generation of harmful substances due to anaerobic environment due to oxygen deficiency. As a result, the aquaculture density can be made uniform in the entire aquaculture tank. In addition, the feeding rate with respect to the amount of feed can be increased, the growth can be made uniform, and it can contribute to the production with a low mortality rate and a high aquaculture density.

Further, according to the present invention, it is not necessary to sprout diatoms in order to maintain the amount of dissolved oxygen. Therefore, since it is not necessary to introduce foreign diatoms, it can be bred in purified seawater from which viruses, bacteria and the like have been removed by a UV sterilizer or the like. As a result, it is possible to prevent the yield from being deteriorated due to the infection of aquatic animals with pathogens. In this way, it is possible to contribute to productivity improvement and running cost reduction.

Further, according to the present invention, since there are few portions in the sand layer where organic matter is deposited and anaerobic, there are few portions that become hedro. Therefore, it is not necessary to feed the area where prawns cannot live, and the waste of feeding can be reduced. In addition, since it does not easily become heddle, there is no need to manually remove the heddle.

Further, in the present invention, it is not necessary to keep the bubble supply means always in operation. The effect can be realized by intensively operating during the time when the activity of aquatic animals becomes active and there is a concern that the dissolved oxygen will decrease, and the time when feces, residual food, and molting shells occur.

Therefore, there is no power that needs to be operated all the time, and it is sufficient to periodically change the water with a pump driven by an AC power source and discharge the accumulated nutrients and the like. Further, during normal aquaculture, a bubble supply means that can be used with a power of about several hundred watts may be driven when necessary. These can be operated using solar panels or electricity stored by midnight electricity in the storage battery, and the electricity bill can be significantly reduced.

Further, according to the present invention, since the sand layer is not hedled, the burden of restoration work of the sand layer during aquaculture is reduced, so that the switching period can be shortened and the next aquaculture can be started, and the number of aquacultures per year can be increased. It can be increased to increase production.

Further, according to the present invention, since the entire aquaculture tank can be efficiently used, it is also suitable for miniaturization of the aquaculture tank. By downsizing the aquaculture tank, it is possible to install equipment that provides lighting and light-shielding parts, or to arrange it indoors, and it becomes easier to control dimming. This makes it possible to adjust the brightness to match the ecology of aquatic animals, which is considered to be active. In addition, by shading during the day, a large amount of algae can be suppressed, especially in the summer. In addition, by blocking light during the day, it is possible to suppress an increase in water temperature due to direct sunlight.

Further, according to the present invention, the need for oxygen supply by diatoms and the like is low. Therefore, by supplying UV-sterilized seawater into the aquaculture tank, the generation of diatoms can be suppressed. This makes it possible to prevent a sharp decrease in dissolved oxygen at night when nocturnal prawns are active.

In addition, the visibility in the aquarium is improved by downsizing and not generating diatoms. This makes it easier to capture the activity status of aquatic animals with a camera, and it is also possible to visually grasp the number of prawns inhabiting the cage. As described above, the aquaculture apparatus and the like of the present invention can significantly reduce power consumption, labor and the like. In addition, inventory that was difficult to grasp in the past can be visualized, and yield and density can be improved, so profits can be expected to improve.

[Test example]
Hereinafter, test examples will be described. The present invention is not limited to the following test examples unless the gist thereof is changed.

[Aquaculture equipment]
-Aquarium: When viewed in a plan view, aquaculture was carried out using a rectangular parallelepiped aquarium having a short side of 1 m, a long side of 2 m and a water depth of about 1 m. Sand was placed and a sand layer was provided on the entire bottom of the water tank.
-Bubble supply means: By adjusting the bubble uptake amount of the bubble nozzle, bubbles around a bubble diameter of about 100 μm having an average rising speed of about 5 to 10 mm / sec were supplied.
As the bubble supply means, the discharge port was placed on the sand layer, and the discharge direction was diagonally downward, which was inclined by about 5 degrees with respect to the horizontal direction toward the sand layer.
Due to such bubble supply, the bubbles gradually rise toward the water surface, and at that time, accompanied by organic matter. The organic matter that floated near the water surface was removed using a net.
・ Aquaculture target: Kuruma prawns were cultivated. The aquaculture density was 40 fish / m ² days, which is higher than the general aquaculture density, and the aquaculture was carried out.

As a result of culturing for 2 months while changing 1/3 of the water once a week, there was almost no death and the number of confirmed deaths was 1. In addition, it was confirmed that the prawns were frequently molted and grew significantly during the aquaculture period. In addition, the activity of prawns was low during this aquaculture. It is considered that this is because it is not necessary to compete for food and the growing environment can be fully utilized, so that the actual occupied area of each individual is wide and the environment is less stressful. In addition, the highly toxic ammonia concentration did not increase in the cultured water during the cultivation. On the other hand, since the nitric acid concentration increased to a certain extent, it is probable that the oxygen concentration was maintained to a certain extent and nitrification proceeded. In addition, nitric acid could be managed with a substance that was not sufficiently toxic by replacing water.

The present invention can be used for aquaculture of prawns and the like, and is industrially useful.

10 Culture tank 100, 1001, 1002 Culture equipment 101 Wall 11 Culture water 111 Water surface 12 Sand layer 13 Filter 20 Water pipe 21 Water supply pipe 22,221 Bubble supply means 23 Circulation pump 30 Foreign matter removal means 301 Comb tooth 302 Net 303 Float 31, 310 Piping 311 Flexible piping 40 Drainage port 41 Drainage filter 50 Water supply means

Claims (7)

Aquaculture tanks that house aquaculture water and
The sand layer placed at the bottom of the aquaculture tank and
It has a bubble supply means, which contains oxygen and sends out bubbles having a bubble rising rate of 5 mm / sec or more, along the sandy ground of the sandy layer and / or toward the sandy ground of the sandy layer.
An aquatic animal farming device that removes organic matter that has floated along with bubbles supplied by the bubble supply means on the surface layer of the farmed water. Aquaculture tanks that house aquaculture water and
The sand layer placed at the bottom of the aquaculture tank and
It has a bubble supply means for delivering oxygen-containing bubbles along the sandy ground of the sandy layer and / or towards the sandy ground of the sandy layer.
An aquatic animal aquaculture device that removes organic matter that has floated along with bubbles supplied by the bubble supply means on the surface layer of the cultured water.
The bubble supply means
It is possible to switch and supply two or more types of bubbles selected from the group consisting of the first bubble to the third bubble having different bubble rising speeds.
The first bubble has a bubble rising rate of 5 mm / sec or less, and has a bubble rising rate of 5 mm / sec or less.
The second bubble has a bubble rising rate of 5 to 500 mm / sec, and the bubble rising rate is higher than that of the first bubble.
Third bubble is a bubble rising speed of 50 mm / sec or more and, Ri said second der having a large bubble rising speed than the bubble,
At least, an aquaculture device that supplies the second bubble or the third bubble. When the dissolved oxygen concentration is improved, the bubble rising rate is set to be small, and when the organic matter is removed, the bubble rising rate is set to the bubbles supplied by the bubble supplying means according to the time zone and / or the oxygen concentration of the aquaculture water. a switching means for switching to a larger, serial mounting aquaculture equipment to claim 2. The aquaculture apparatus according to any one of claims 1 to 3, further comprising a foreign matter removing means for removing the floating organic matter on the surface layer of the aquaculture water. A plurality of the bubble supply means are arranged.
The aquaculture apparatus according to any one of claims 1 to 4, wherein the aquaculture tanks are arranged so that the supply directions are different when viewed in a plan view. The aquaculture apparatus according to any one of claims 1 to 5, wherein the aquatic animal is prawn. An aquaculture tank containing aquaculture water, a sand layer located at the bottom of the aquaculture tank, and along the sandy ground of the sandy layer and / or toward the sandy ground of the sandy layer, containing oxygen, the rate of bubble rise. It is a method of cultivating aquatic animals using a culturing device having a bubble supply means for sending out bubbles having a value of 5 mm / or more.
The bubble supply step of supplying bubbles by the bubble supply means and
A method for culturing aquatic animals, which comprises a removal step of removing organic matter that has floated along with the bubbles.

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