Shellfish culture system

Abstract

To provide a shellfish culture system that is excellent in cost reduction.SOLUTION: A shellfish culture system includes: a culture water tank for culturing shellfish; a sedimentation tank that causes a counter flow with a water level difference to the culture water tank; and a purification tank for purifying the water of the sedimentation tank, where the water purified by the purification tank branches into a plurality of channels and is sprayed into the culture water tank.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a shellfish farming system for farming shellfish such as abalone. [Background technology]

[0002] Closed-recirculating land-based aquaculture is not affected by the marine environment and can be carried out in inland areas with no coastline, and it is expected that it will also be used to farm abalone and other shellfish, but there are issues regarding cost. For example, Patent Documents 1 and 2 disclose a method of aerating an aquaculture tank by sending air into the water to exchange the water and supply the oxygen necessary for the survival of shellfish. However, this requires the installation of an aeration pump and control to ensure uniform aeration. It is also important to maintain good water quality, which is the habitat for shellfish, and water temperature must also be controlled. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-290040 A [Patent Document 2] JP 2020-129971 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention aims to provide a shellfish farming system that is excellent in terms of cost reduction, etc. [Means for solving the problem]

[0005] The shellfish farming system of the present invention comprises an aquaculture tank for cultivating shellfish, a sedimentation tank in which countercurrent flows between the aquaculture tank and the sedimentation tank due to the water level difference, and a purification tank for purifying the water in the sedimentation tank, and is characterized in that the water purified in the purification tank is branched into multiple streams and sprayed into the aquaculture tank. By using the difference in water levels to flow countercurrently from the culture tanks where abalone and other fish are cultivated into a settling tank, and after purification, the water is branched into multiple channels from the top of the culture tank and sprayed, it is possible to circulate the water and supply oxygen to the shellfish at low cost, without the need for aeration devices or complex controls. In the present invention, the septic tank may have a biological filtration tank and / or a protein skimmer tank, and the septic tank may further have a plant tank. For example, biological filtration or protein skimmers can be used to detoxify ammonia and remove mucus, while plants such as quinoa, which can germinate in salt water, can be used to remove nitrates and the like. In the present invention, the water purified in the septic tank may be sprayed into the aquaculture tank via a water temperature control unit using one or more types of heat selected from incineration heat, underground heat, and geothermal heat. For example, by using thermal energy generated by waste incinerators or geothermal heat to control the temperature of circulating water, it is possible to cut costs by reducing fossil fuel consumption and protect the global environment by reducing carbon dioxide emissions. Effect of the Invention

[0006] According to the present invention, a closed recirculating land-based aquaculture of shellfish is possible with a simple system configuration, and aquaculture can be carried out even in inland areas without being affected by the marine environment. The water level in the culture tank is set higher than the settling tank, and by utilizing this water level, a natural water flow occurs in the culture tank, resulting in low cost. Also, purified water is pumped up and sprayed into the culture tank, eliminating the need for an aeration device or its control. [Brief description of the drawings]

[0007] [Figure 1] A schematic diagram showing an example of the configuration of a shellfish farming system is shown below. [Diagram 2] FIG. 2 is a perspective view of a part of the aquaculture tank and the sedimentation tank. [Diagram 3] An example of the structure of the applicator is shown in a perspective view. [Figure 4] The appressorium contained in the cage is shown in plan view. [Diagram 5]The caged apprehension vessels in the aquaculture tank are shown in a partial cross-sectional view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The shellfish farming system is used, for example, for closed-recirculation land-based farming of abalone (black abalone, Hokkaido abalone, Madaka abalone, Megai abalone, etc.). As shown in FIG. 1, the system has an aquaculture tank 10 for cultivating shellfish, a sedimentation tank 20 in which countercurrent flows due to the difference in water level between the aquaculture tank and the sedimentation tank, and a purification tank (31, 32, 33) for purifying the water in the sedimentation tank. The water purified in the purification tank is branched into multiple channels and sprayed into the aquaculture tank 10. As will be described in detail later, the water level of the aquaculture tank 10 is set to be higher than the water level of the sedimentation tank 20. The arrows in FIG. 1 indicate the path of the circulating water. In this specification, "water" refers not only to seawater, but also to artificial seawater having a salinity similar to or slightly higher than that of seawater. The multiple aquaculture tanks 10 are all connected to a common settling tank 20, and water purified in a common purification tank is pumped up and branched out from the top of the aquaculture tanks 10 for spraying. It is preferable that the shellfish farming system be installed in an environment that is unlikely to be affected by weather or outside temperature, and the young shellfish can be grown in the farming tank 10 until they reach a size that makes them suitable for shipment.

[0009] A culture tank 10 for storing water contains a plurality of cages 11 and attachment devices 12 for housing the abalone in the cages 11 and attaching the abalone to them. FIG. 3 shows an example of an appressor 12, FIG. 4 shows an example of an appressor 12 housed in a cage 11, and FIG. 5 shows an example of an appressor 12 housed in a cage 11 in an aquaculture tank 10. The aquaculture tank 10 may be, for example, a tank approximately 9 m long, 1 m wide, and 0.4 m deep, and from the standpoint of ease of cleaning and prevention of damage, the inside may be covered with a waterproof sheet such as a tarpaulin. The cage 11 may be, for example, a resin or wire mesh measuring approximately 0.8 m in length, 1 m in width, and 0.3 m in depth, and the mesh size is not particularly limited as long as the shellfish cannot move outside the cage, but may be, for example, 6 mesh. It is preferable that each cage 11 is installed so that its upper side is engaged with the upper edge of the aquaculture tank 10, or the like, and so that it floats at a certain height above the bottom of the aquaculture tank 10, as shown in Figure 5. This makes it easier for leftover food and feces to fall below the cage 11, making it easier to keep the inside of the cage 11 clean. However, the present invention is not limited to being installed in a suspended state. In addition, there is no particular limit to the number of aquaculture tanks or the number of cages in the aquaculture tanks. For example, by providing multiple aquaculture tanks, it is easier to change the amount of feed and growth conditions, making it easier to manage growth and adjust yields.

[0010] As shown in Figure 3, the attachment device 12 is an example in which multiple upper plates 14 are fixed onto side plates 13a, 13b arranged in a roughly lattice pattern, and three horizontal walls 13a are arranged roughly parallel to each other, with the central horizontal wall 13a intersecting the vertical walls 13b and the vertical walls 13b being sandwiched between the outer horizontal walls 13a. Abalone that prefer dark places tend to attach to the underside of the upper plate 14, for example, and by turning over the attachment organelle 12, it is easy to separate the abalone that has attached to the underside of the upper plate 14. In this embodiment, a vertical wall 13b is formed with a wandering hole 13c through which the abalone can wander. The side panels 13a, 13b and the top panel 14 may be made of materials such as synthetic resin, ceramic, or metal, and each surface may be smooth or may have fine irregularities or through holes, but it is preferable that the irregularities are not large so as not to cause stress to the abalone.

[0011] A water sprinkler port (not shown) is provided above the cage 11 in the aquaculture tank 10. Each sprinkler outlet may be disposed above each cage 11 by repeatedly branching using, for example, a branch-out construction method. The sprinkler nozzle may be one whose opening diameter can be adjusted so as to easily incorporate fine air bubbles into the water being sprinkled. For example, as shown in FIG. 1, a main pipe is laid along the longitudinal direction of the aquaculture tank 10, and multiple sprinkler pipes are branched off from the main pipe via valves. By adjusting the opening and closing amount of each valve, the flow rate of the multiple sprinkler pipes can be made uniform. As shown in FIG. 2, by disposing the aquaculture tank 10 above the settling tank 20, a water level difference between the aquaculture tank 10 and the settling tank 20 can be easily provided. Water in the aquaculture tank 10 can flow countercurrently into the sedimentation tank 20 by passing through piping 50 connected to the aquaculture tank drain outlet 10a located on the side wall of the aquaculture tank 10 (for example, near the bottom of the right wall in Figure 2) and the sedimentation tank water supply inlet 20a located below it. The aquaculture tank outlet 10a and the settling tank water inlet 20a may be provided with valves or the like to facilitate water exchange.

[0012] The water in the settling tank 20 passes through a purification tank, where ammonia is rendered harmless and mucus, nitric acid, etc. are removed. The septic tank may be composed of a septic tank using plants (plant tank) 31, a septic tank using a protein skimmer (protein skimmer tank) 32, and a biological filtration tank 33, as shown in FIG. In the plant tank 31, for example, by growing quinoa, which can germinate even in seawater, while removing nitric acid and the like, it is possible to supply water necessary for growing plants while improving the water quality for shellfish. Abalone excrete a large amount of mucus, so it is preferable for the mucus to be removed in a protein skimmer tank 32. The biological filtration tank 33 contains a treatment material with aerobic bacteria or the like attached thereto, and by bringing the treatment material into contact with the water from the settling tank, the ammonia can be rendered harmless. In this embodiment, a disinfection device 34 using ultraviolet rays or the like is disposed in the biological filtration tank 33, but the biological filtration tank or the like may also be used to adjust the pH of the water or supply minerals. In this embodiment, an integrated tank is used so that the water accumulated in the settling tank 20 flows into the protein skimmer tank 32 via the plant tank 31, but the present invention is not limited to this. Furthermore, the order of countercurrent flow to the plant tank 31, protein skimmer tank 32, and biological filtration tank 33 is not limited to that in this embodiment, and the countercurrent flow from the settling tank 20 to each septic tank 31, 32, 33, etc. may also utilize the water level difference, or water may be transported using a pump if necessary.

[0013] Water is sprayed into the aquaculture tank 10 by pumping, with the water temperature being controlled. In this embodiment, the water that has passed through the biological filtration tank 33 passes through a water temperature control unit 40 . In the water temperature management unit 40, for example, waste heat from an incinerator or the like may be used to heat the circulating water in winter, and geothermal heat or the like may be used to cool the circulating water in summer. By controlling the water temperature before watering the aquaculture tank 10, it becomes easier to cultivate abalone throughout the year. The shellfish farming system of the present invention supplies oxygen to the farming tanks by spraying pumped circulating water, and can also circulate water countercurrently in the settling tank and subsequent water purification as needed by utilizing the water level difference, resulting in a low-cost, stable farming system with a simple structure.

Claims

1. A shellfish farming system comprising: an aquaculture tank for cultivating shellfish; a sedimentation tank in which water flows countercurrently to the aquaculture tank due to the difference in water level; and a purification tank for purifying the water in the sedimentation tank, wherein the water purified in the purification tank is branched into multiple channels and sprayed into the aquaculture tank.

2. The shellfish farming system according to claim 1, characterized in that the purification tank has a biological filtration tank and / or a protein skimmer tank.

3. The shellfish farming system according to claim 2, characterized in that the septic tank further comprises a plant tank.

4. A shellfish farming system as described in any one of claims 1 to 3, characterized in that the water purified in the septic tank is sprayed into the aquaculture tank through a water temperature control unit using one or more types of heat selected from incineration heat, underground heat, and geothermal heat.

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