Aquaculture device

Abstract

To provide a technique capable of efficiently collecting and removing unnecessary objects in a water tank.SOLUTION: An aquaculture device includes a water tank for rearing aquatic organisms, a water supply unit for supplying rearing water to the water tank, a water discharge unit for discharging the rearing water in the water tank through a drain port formed in the water tank, and an exclusion unit for suppressing intrusion of aquatic organisms into a prescribed exclusion area set in the water tank by using actions of both or one of a medium repelling aquatic organisms and a medium attracting aquatic organisms in water.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a technique for collecting and removing unwanted objects from an aquarium. [Background technology]

[0002] As global demand for marine resources increases, efforts are underway to develop aquaculture technologies that will ensure a stable supply of aquatic organisms. In recent years, as the effects of global warming and marine pollution have become increasingly serious problems, land-based aquaculture, which has fewer of these impacts, has been attracting attention. Land-based aquaculture has the advantages of being less restricted by location than marine aquaculture, being less susceptible to weather and natural disasters by using indoor facilities, and reducing the burden that aquaculture places on the environment. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6362056 [Patent Document 2] Patent No. 6741303 [Patent Document 3] Japanese Patent Application Laid-Open No. 2006-129862 Summary of the Invention [Problem to be solved by the invention]

[0004] Crustaceans such as shrimp are one of the aquatic organisms that are raised in land-based aquaculture. In addition to molted shells, shrimp breeding tanks generate unwanted objects such as feces, leftover food, and dead bodies (hereinafter referred to as "garbage"). In land-based shrimp breeding, the water in the breeding tanks (hereinafter referred to as "breeding water") is purified and circulated to maintain clean water quality. To prevent shrimp from being discharged along with the breeding water, the drain outlet is usually equipped with a strainer with a mesh size that shrimp cannot pass through.

[0005] Among the waste, shrimp carcasses and molted shells are about the same size as the shrimp. In particular, molted shells are generated in large quantities due to the frequent molting that occurs as shrimp grow. These unwanted objects have difficulty passing through the strainer, so they are prone to clogging. However, if the strainer is removed, the shrimp will be discharged from the tank. Therefore, strainers are frequently cleaned at land-based shrimp farms. As such, under current circumstances, it takes a considerable amount of effort to remove waste from tanks where shrimp and other aquatic organisms are raised.

[0006] The present invention has been made in view of the above circumstances, and one of its objects is to provide a technique for efficiently collecting and removing unwanted objects in an aquarium. [Means for solving the problem]

[0007] In one embodiment of the present invention, the aquaculture device comprises an aquarium for raising aquatic organisms, a water supply unit that supplies breeding water to the aquarium, a drainage unit that discharges the breeding water from the aquarium through a drain outlet formed in the aquarium, and an exclusion unit that prevents aquatic organisms from invading a designated exclusion area set in the aquarium by applying, in the water, both or one of a medium that repels aquatic organisms and a medium that attracts aquatic organisms. [Effects of the Invention]

[0008] The present invention provides a technology that can efficiently collect and remove unwanted objects from an aquarium. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of an aquaculture device according to a first embodiment. [Figure 2] FIG. 2 is a perspective view showing the structure of the water tank and its surroundings in the first embodiment. [Figure 3] FIG. 2 is a plan view (part 1) of the water tank in the first embodiment. [Figure 4] FIG. 2 is a second plan view of the water tank in the first embodiment. [Figure 5]FIG. 3 is a plan view (part 3) of the water tank in the first embodiment. [Figure 6] FIG. 10 is a schematic diagram of an aquaculture device according to a second embodiment. [Figure 7] FIG. 10 is a side view showing the bottom structure of the water tank in the second embodiment. [Figure 8] FIG. 10 is a schematic diagram of an aquaculture device according to a third embodiment. [Figure 9] FIG. 2 is a functional block diagram of the emission control device. [Figure 10] FIG. 1 is a side view showing the bottom structure of an aquarium in which an underwater structure is provided. [Figure 11] Figure 11(a) is a schematic diagram of an aquarium with a drain outlet at the bottom. Figure 11(b) is a schematic diagram of an aquarium with a drain outlet on the side wall. Figure 11(c) is a schematic diagram of an aquarium with an L-shaped drain pipe with a drain outlet facing sideways. Figure 11(d) is a schematic diagram of an aquarium with an L-shaped drain pipe with a drain outlet facing downwards. [Figure 12] Figure 12(a) is a schematic diagram of an aquarium with a drain outlet having a double-pipe structure. Figure 12(b) is a schematic diagram of an aquarium with a depression and a drain outlet in the center of the bottom. Figure 12(c) is a schematic diagram of an aquarium with a drain outlet in the deepest part of the bowl-shaped bottom. Figure 12(d) is a schematic diagram of an aquarium with a slope and a drain outlet on the periphery of the bottom. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. First, as a first embodiment, an overview of the collection and removal of debris in a circular aquarium will be described. Next, as a second embodiment, an overview of the collection and removal of debris in a raceway-type aquarium will be described. Furthermore, as a third embodiment, an overview of the collection and removal of debris in a rectangular parallelepiped aquarium will be described. In the following description, the first to third embodiments will be collectively referred to as "the present embodiment."

[0011] [First embodiment] FIG. 1 is a schematic diagram of an aquaculture device 100 according to the first embodiment. The aquaculture device 100 realizes closed-circulation land-based aquaculture, and includes an aquarium 110 for raising aquatic organisms 101, a circulation path 111 for circulating the water (breeding water) in the aquarium 110, and a biological filtration tank 141 provided in the circulation path 111. The circulation path 111 is provided with a drain outlet 112, a first pump 113, and a water supply port 114. By driving the first pump 113, the breeding water circulates through the circulation path 111. The first pump 113 functions as a "circulation device" that adjusts the amount of water circulated. These aquaculture facilities are placed in an indoor facility.

[0012] Land-based aquaculture methods are generally broadly divided into free-flowing and closed-circulation systems. The free-flowing system involves pumping water from the ocean or river into an aquarium 110 and then draining the contaminated water from the aquarium 110, i.e., maintaining the water purity through water exchange. In contrast, the closed-circulation system utilizes a circulation path 111 for reusing the water stored in the aquarium 110, and maintains the water purity by passing it through a filter tank installed in the circulation path 111. A semi-circulation system, which combines the free-flowing and closed-circulation systems, also exists, in which the water is circulated while a portion of it is exchanged. In this embodiment, the closed-circulation system, which is a type of land-based aquaculture, is employed to prevent the introduction of pathogens from outside and reduce seasonal factors that affect water temperature, etc. The temperature of the water is set to a temperature suitable for the growth of the aquatic organisms 101.

[0013] In this embodiment, the aquatic organism 101 refers to a shrimp, but it may also be a saltwater fish or a freshwater fish. The aquatic organism 101 may also be a crustacean or shellfish other than shrimp, or other seafood. The composition of the rearing water is adjusted depending on whether the aquatic organism 101 is a saltwater organism or a freshwater organism.

[0014] A physical filter 140 is provided downstream of the aquarium 110 in the circulation path 111, and a biological filtration tank 141 is provided downstream of that. In this embodiment, no strainer is provided at the drain outlet 112. The physical filter 140 captures all the waste, such as the molted shells 102 and leftover food 103, discharged from the drain outlet 112.

[0015] Toxic ammonia is generated in the aquarium 110 due to the metabolic activity of aquatic organisms 101 and the decomposition of organic matter such as leftover food 103. For this reason, the breeding water is circulated and passed through a biological filtration tank 141 for biological filtration, where the ammonia is decomposed and converted into less toxic nitrate. The biological filtration tank 141 holds nitrifying bacteria (microorganisms) that oxidize ammonia in oxygen-containing water and convert it into nitrite and then nitrate.

[0016] A foam separator 142 is connected to the biological filtration tank 141. The water discharged from the water tank 110 and guided to the biological filtration tank 141 is guided to the foam separator 142 by the drive of the second pump 115. The foam separator 142 separates the organic matter contained in the water by adsorbing it into foam and floating it to the surface, and then returns the water to the biological filtration tank 141.

[0017] The water nitrified in the biological filtration tank 141 is guided to the denitrification tank 143 by the operation of the third pump 116, and then returned to the biological filtration tank 141. The denitrification tank 143 holds denitrifying bacteria, which reduce the nitrate contained in the filtered water to nitrogen gas and release it into the atmosphere. After being detoxified in this way, the water in the biological filtration tank 141 is pumped up by the first pump 113 and supplied to the aquarium 110. Note that if the aquatic organism 101 is a shrimp, the third pump 116 and denitrification tank 143 may not be provided.

[0018] The aquaculture device 100 is further provided with an oxygen supply device 144, a feeding device 150, and a power supply device 160. The oxygen supply device 144 supplies oxygen to the breeding water in the aquarium 110. The feeding device 150 functions as a "feeding section" that supplies food into the aquarium 110.

[0019] A conductive cable 161 extends from the power supply device 160. An electrode 162 is connected to the end of the conductive cable 161. The electrode 162 is provided around the center of the bottom of the aquarium 110. As will be described in detail later, a weak current is passed from the power supply device 160 to the electrode 162 to prevent aquatic organisms 101 from entering the area surrounded by the electrode 162. The electrode 162 functions as an "exclusion section."

[0020] 2 is a perspective view showing the structure of the aquarium 110 and its surroundings in the first embodiment. For convenience of explanation, the oxygen supply device 144 and the feeding device 150 are not shown.

[0021] The water tank 110 in the first embodiment is a circular water tank having a circular shape in a plan view, and has a drain outlet 112 provided at the center of the bottom. Electrodes 162 connected to a power supply device 160 via conductive cables 161 are provided around the drain outlet 112. While six electrodes 162 are provided in FIG. 2, the number of electrodes 162 may be less than six or may be seven or more.

[0022] A drain pipe 117 is provided from the drain outlet 112 downward in the aquarium 110. The drain pipe 117 functions as a "drainage section" that discharges the breeding water out of the aquarium 110. A water supply pipe 118 is provided so as to penetrate the side wall 110a of the aquarium 110. The water supply pipe 118 is connected to the piping downstream of the biological filtration tank 141 to form a circulation path 111, and functions as a "water supply section" that supplies the breeding water to the aquarium 110.

[0023] The open end of the water supply pipe 118, i.e., the water supply port 114, is oriented in the tangent direction to the inner circumferential surface of the aquarium 110. Therefore, when breeding water is discharged from the water supply pipe 118, a unidirectional water flow is generated centered directly above the drain port 112 (see the arrow in the figure). In other words, a circular water flow, i.e., a swirling flow of breeding water, is generated in the aquarium 110. In the case of Figure 2, the water supply port 114 is oriented to the left, so a counterclockwise swirling flow is generated in the aquarium 110.

[0024] Fig. 3 is a plan view (part 1) of the aquarium 110 in the first embodiment. For convenience of explanation, Fig. 3 omits illustration of the aquatic organisms 101, molted shells 102, remaining food 103, drain outlet 112, oxygen supply device 144, feeding device 150, and electrodes 162. Here, we will explain the setting of the exclusion area 120, which is carried out as a preparation before raising the aquatic organisms 101 (shrimp) in the aquarium 110. The exclusion area 120 refers to an area from which shrimp should be excluded.

[0025] As described above, a counterclockwise swirling flow occurs in the circular aquarium 110. At this time, areas within the aquarium 110 have fast and slow flow velocities. More specifically, in the first embodiment, the flow velocity increases toward the side wall 110a of the aquarium 110 and decreases toward the center P. Furthermore, due to centrifugal force generated by the swirling flow of the breeding water and frictional resistance between the bottom of the aquarium 110 and the breeding water, the breeding water near the water surface Wf of the aquarium 110 flows toward the side wall 110a. The breeding water near the side wall 110a flows toward the bottom of the aquarium 110. The breeding water near the bottom of the aquarium 110 flows toward the center P when the aquarium 110 is viewed from above. Due to the difference in swirling flow velocity and the water currents generated by the swirling flow, debris tends to accumulate near the bottom of the aquarium 110 and around the center P. Hereinafter, the area where debris tends to accumulate is also referred to as the accumulation area.

[0026] 3, a plurality of measurement points 119 are set in the aquarium 110. The measurement points 119 are locations where a current meter, a current direction meter, etc. are installed to measure the flow velocity and flow direction of the breeding water.

[0027] More specifically, a situation in which a flow meter is installed at each measurement point 119 to measure the flow velocity of the rearing water and an area with a relatively slow flow velocity is identified as the retention area will be described with reference to FIG. 3 as an example. For example, the retention area may be an area including the measurement point 119 with the slowest flow velocity and the measurement points 119 adjacent to that measurement point 119. Alternatively, an average flow velocity is calculated from the flow velocities measured at all measurement points 119. In this case, an area including measurement points 119 with a flow velocity equal to or lower than the average flow velocity may be identified as the retention area. Using this method, the retention area within the aquarium 110 is identified.

[0028] Measurement points 119 may be set at any location in water tank 110. In Fig. 3, for example, center P is used as the reference and measurement points 119 are set at equal intervals in the vertical and horizontal directions.

[0029] In Fig. 3, it is assumed that the flow velocity at each measurement point 119 is measured and the flow velocity at measurement point 119P located at center P is the slowest. In Fig. 3, the region including measurement point 119P and measurement points 119a to 119d adjacent to measurement point 119P in the vertical and horizontal directions, more specifically, the region inside the circle circumscribing measurement points 119a to 119d, is identified as the stagnation region.

[0030] In FIG. 3, a flow direction meter is installed at each measurement point 119 to measure the flow direction of the breeding water at the bottom of the aquarium 110. Assume that the measurement results of the flow direction meter at each measurement point 119 reveal that the direction of the water flow in the radial direction of the circular aquarium 110 is concentrated at measurement point 119P. In this case, the area around measurement point 119P may be identified as the retention region. More specifically, the area inside a circle circumscribing measurement points 119a to 119d adjacent to measurement point 119P in the vertical and horizontal directions may be identified as the retention region. Alternatively, the retention region may be identified by combining the measurement results of the current meter and the flow direction meter.

[0031] 4 is a second plan view of the aquarium 110 in the first embodiment. For ease of explanation, the drain outlet 112, oxygen supply device 144, feeding device 150, and electrode 162 are not shown in FIG.

[0032] As described above, when a swirling flow occurs, the area around the center P of the aquarium 110 becomes a retention area, and debris such as molted shells 102 and remaining food 103 accumulates therein. Therefore, in the first embodiment, a drain outlet 112 is provided at the center P of the aquarium 110. The drain outlet 112 is provided at the bottom of the aquarium 110.

[0033] Shrimp tend to gather in places where garbage accumulates (retention areas). Providing a drain outlet 112 in the retention area improves garbage discharge, but increases the risk of shrimp being discharged along with the garbage. To prevent shrimp from being discharged, it is necessary to keep shrimp away from the retention area (near the drain outlet). Therefore, the retention area is set as an area from which shrimp should be excluded, i.e., an exclusion area 120.

[0034] 5 is a plan view (part 3) of the aquarium in the first embodiment. For convenience of explanation, the oxygen supply device 144 and the feeding device 150 are omitted from FIG.

[0035] In order to efficiently collect and quickly remove waste while reducing the above-mentioned risks, when raising aquatic organisms 101 (shrimp), electrodes 162 are installed in a manner that circumscribes the exclusion zone 120, as shown in FIG. 5 . A weak current is passed from the power supply 160 to the electrodes 162. An electric field is generated between adjacent electrodes 162 along the exclusion zone 120. In other words, an electric barrier is formed surrounding the exclusion zone 120. Since aquatic organisms 101 have a dislike for electricity, this method can prevent the aquatic organisms 101 from entering the exclusion zone 120. Passing a weak current through the electrodes 162 to keep the aquatic organisms 101 away from the exclusion zone 120 can be achieved by applying known technology (see Patent Documents 1 and 2).

[0036] On the other hand, debris such as molted shells 102 and leftover food 103 passes through the gaps between the electrodes 162 and washes up in the exclusion area 120. The debris that washes up in the exclusion area 120 is discharged to the outside of the aquarium 110 through a drain outlet 112 located at the center P of the aquarium 110. In other words, by providing the electrodes 162, it is possible to separate the debris generated in the breeding water of the aquarium 110 from the aquatic organisms 101.

[0037] In summary, a strainer can be provided at the drain outlet 112 to prevent aquatic organisms 101 (shrimp) from being discharged from the aquarium 110. However, because debris accumulates in the strainer, cleaning the strainer becomes a burden on the worker. In the first embodiment, the drain outlet 112 is provided in an area of the aquarium 110 where debris is likely to accumulate (retention area), and the retention area is designated as the exclusion area 120. Electrodes 162 are provided around the exclusion area 120, and a weak current is passed through them to generate an electric barrier. This method prevents shrimp from approaching the drain outlet 112, so that debris can be discharged from the aquarium 110 without using a strainer and shrimp can be prevented from being discharged.

[0038] [Second embodiment] FIG. 6 is a schematic diagram of an aquaculture device 100 according to the second embodiment. The second embodiment employs a so-called raceway-type water tank 110. The water tank 110 has semicircular (R-shaped) corners 110b at both ends in the longitudinal direction. A partition plate 121 extending longitudinally through the center of the width of the water tank 110 divides a water channel 122 in the width direction. The pair of divided water channels 122a, 122b are parallel to each other and connected at the corner 110b. A flow in one direction (counterclockwise in the figure) is generated in the annular water channel 122 (see the arrow in the figure).

[0039] A water supply pipe 118 is provided so as to penetrate the side wall 110a of the aquarium 110. The water supply pipe 118 extends inside the aquarium 110 and branches into multiple pipes (branch pipes 118a). The open end of each branch pipe 118a (i.e., water supply port 114) faces downstream of the aquarium 110, and breeding water is discharged downstream, thereby generating the unidirectional water flow described above.

[0040] It is known that near the upstream end of the water channel 122a (122b), i.e., in the area along the partition plate 121 near the downstream end of each corner 110b, the water flow is likely to change direction at the corner 110b, causing localized vortices and debris to accumulate (see Patent Document 3). In other words, the location where the vortex occurs becomes a retention area, so a drain outlet 112 is provided at the bottom of the water tank 110 and within the retention area. In the second embodiment, the retention area identified in this manner is set as the exclusion area 120. In the second embodiment, the exclusion area 120 is preferably set within one-fifth of the upstream side of the water channel 122a (122b) on the partition plate 121. Furthermore, in the second embodiment, there are two exclusion areas 120 (drain outlets 112).

[0041] In a raceway-type aquarium 110, depending on the feeding position, fresh bait 104 may be discharged from the drain outlet 112 immediately after feeding. For example, suppose feeding is performed in the first area 123, which is located on the opposite side of the partition plate 121 from the exclusion area 120. In this case, the bait 104 will quickly drift to the exclusion area 120, increasing the probability that it will be discharged from the drain outlet 112. The bait 104 will not be ingested by the aquatic organisms 101 and will be wasted.

[0042] Therefore, in the second embodiment, feeding is carried out in a second region 124a (124b) in the waterway 122a (122b) that is located immediately downstream of and after the exclusion region 120a (120b), as shown in Figure 6. Hereinafter, the second region 124a located immediately after the exclusion region 120a will be described.

[0043] The second region 124a includes point Pa1. Point Pa1 is located downstream of exclusion region 120a and is the point at which the linear distance to a point within the other exclusion region 120b is greatest. More specifically, point Pa1 is tangent to exclusion region 120a at point Pa2, and is a perpendicular point to sidewall 110a on a line extending from partition plate 121 toward the outside of the water tank 110. In the second embodiment, point Pb, which is the center of drain outlet 112, is set as a point within exclusion region 120b.

[0044] A line is set that intersects the side wall 110a at right angles and touches the exclusion zone 120b on the upstream side of the water channel 122. The point of intersection with the water tank 110 is defined as point Pa3, and the point of contact with the exclusion zone 120b is defined as point Pa4. The second zone 124a is set downstream of the line connecting points Pa1 and Pa2, and upstream of the line connecting the partition plate 121 with a midpoint on the side wall 110a between points Pa1 and Pa3 (hereinafter referred to as the "zone midpoint") Pa5. The line connecting the partition plate 121 and the zone midpoint Pa5 (hereinafter referred to as the "midpoint line") is set perpendicular to the side wall 110a. The zone midpoint Pa5 is set downstream of the exclusion zone 120a and upstream of the exclusion zone 120b. Preferably, the second region 124a is set downstream of the line connecting points Pa1 and Pa2 and upstream of the line connecting points Pa3 and Pa4, within the upstream third of the range.More preferably, the second region 124a is set downstream of the line connecting points Pa1 and Pa2 and upstream of the intermediate line, within the upstream half of the range.

[0045] In second region 124a, which includes point Pa1, feeding pipe 151a extends from sidewall 110a of aquarium 110 in the width direction of waterway 122a. More specifically, the upstream boundary line of feeding pipe 151a in the width direction overlaps with the line connecting points Pa1 and Pa2. Feeding pipe 151a is provided with multiple feeding ports 152. Food 104 stored in feeding device 150 is dispensed from feeding ports 152 via feeding pipe 151a. Dispensed food 104 drifts counterclockwise in waterway 122. Similarly, feeding pipe 151b is provided in second region 124b immediately downstream of and after exclusion region 120b, and feeding is carried out.

[0046] The position where the food 104 falls into the rearing water, in other words, the position where the food 104 is actually dispensed, may be tangent to the line connecting points Pa1 and Pa2. For example, the upstream boundary in the width direction of the feeding port 152 may overlap with the line connecting points Pa1 and Pa2. The food 104 may be dispensed by being thrown into the air and dropping at a position tangent to the line connecting points Pa1 and Pa2. Alternatively, the food 104 may be mixed into the rearing water in advance, and the rearing water may be supplied at a position tangent to the line connecting points Pa1 and Pa2, and the food 104 may be dispensed by scattering it.

[0047] This method makes it possible to buy more time for fresh bait 104 to be discharged from drain outlet 112 compared to when feeding in first area 123. Therefore, the aquatic organisms 101 have more opportunities to ingest bait 104. Since there is a higher possibility that the aquatic organisms 101 will have ingested all of the bait 104 before it is discharged from drain outlet 112, it is possible to reduce waste of bait 104 that would otherwise be discharged early.

[0048] As in the first embodiment, the electrode 162 may be provided in a manner that circumscribes the exclusion area 120. As described above, the installation of the electrode 162 can prevent the aquatic organisms 101 (shrimp) from being expelled.

[0049] FIG. 7 is a side view showing the bottom structure of water tank 110 in the second embodiment. In this embodiment, the food 104 is formed as a lump, i.e., is solid. The specific gravity of the food 104 is equal to or greater than the specific gravity of the breeding water. Therefore, the food 104 sinks to the bottom of the aquarium 110 immediately after being fed.

[0050] In the aquarium 110 of the second embodiment, a unidirectional water flow occurs in the breeding water. The bait 104 that sinks to the bottom flows from upstream to downstream in the waterway 122. When fed in the second area 124, the bait 104 stays in the breeding water for a longer period of time than in the first area 123. Therefore, the time that the aquatic organisms 101 can consume the bait 104 can be extended.

[0051] One possible method for further extending the time that the aquatic organisms 101 consume the bait 104 is to change the structure of the bottom of the aquarium 110. To this end, grooves 125 and protrusions 126 are provided on the bottom of the aquarium 110 as shown in FIG. 7. More specifically, the grooves 125 and protrusions 126 are provided on the bottom of the aquarium 110 in the width direction of the water channel 122a (122b). The grooves 125 and protrusions 126 may be provided in a regular order (for example, alternately) in the water flow direction, or in a random order. Only the grooves 125 or only the protrusions 126 may be provided.

[0052] The fed bait 104 repeats this movement of being captured by the grooves 125 or protrusions 126 and being carried away by the water current. In the second embodiment, the depth of the grooves 125 is shallower than the length of the bait 104, and the height of the protrusions 126 is shorter than the length of the bait 104. Therefore, the bait 104 does not remain captured in the grooves 125 or protrusions 126 in the same place for an excessively long time, but moves downstream at appropriate time intervals. This method can slow the average movement speed of the bait 104 compared to when the bottom of the aquarium 110 is flat. Therefore, it is easier for the aquatic organisms 101 to ingest all of the bait 104.

[0053] In summary, in a raceway-type aquarium 110, debris tends to collect in the area where a local vortex occurs due to a change in water flow direction at a corner 110b. For this reason, a drain outlet 112 is provided in the area where the vortex occurs (retention area), and the retention area is set as the exclusion area 120. In the second embodiment, feeding is performed in an area (second area 124) immediately downstream of and immediately behind the exclusion area 120. This extends the time until the bait 104 is discharged from the drain outlet 112. In addition, grooves 125 and protrusions 126 are provided on the bottom of the aquarium 110. This slows down the average movement speed of the bait 104. These methods prevent the bait 104 from being discharged prematurely, providing the aquatic organisms 101 with ample opportunities to ingest the bait 104.

[0054] [Third embodiment] FIG. 8 is a schematic diagram of an aquaculture device 100 according to the third embodiment. The aquaculture device 100 in Figure 8 employs a rectangular parallelepiped aquarium 110. In the following description of the aquarium 110, the left-right direction is the x-axis, the front-back direction is the y-axis, and the up-down direction is the z-axis. For convenience of explanation, the water supply pipe 118, oxygen supply device 144, and feeding device 150 are not shown in Figure 8.

[0055] An air duct 127 is provided at the diagonally upper part of the aquarium 110 (above the aquarium 110 in the positive y-axis and positive z-axis directions). Air is blown out from the open end (air outlet 128) of the air duct 127 toward the water surface Wf in the negative y-axis and negative z-axis directions. The air blown out from the air outlet 128 generates a swirling flow of the breeding water around the x-axis in the aquarium 110 (see the arrow in the figure). The swirling flow causes debris in the breeding water to gradually accumulate around the periphery of the bottom of the aquarium 110 in the positive y-axis and negative z-axis directions, more specifically, around the line connecting points A and B in Figure 8. In other words, the area around the line connecting points A and B becomes the accumulation area. In the third embodiment, a drain outlet 112 is provided at point C, which is the midpoint between points A and B. Therefore, point C and its surroundings are set as the exclusion area 120.

[0056] The aquaculture device 100 in the third embodiment is provided with two drain outlets 112. As described above, shrimp tend to gather in areas where garbage is likely to accumulate (retention areas). If a drain outlet 112 is provided in the retention area, there is a high risk that the shrimp will be expelled if the drain outlet 112 is left open. One way to avoid this risk is to open the drain outlet 112 only when a predetermined amount of garbage has accumulated in the exclusion area 120. However, if there is only one drain outlet 112, the water will not be drained unless garbage is accumulated, and therefore the breeding water will not circulate. Therefore, in the third embodiment, a first drain outlet 112a and a second drain outlet 112b are provided in the aquarium 110.

[0057] The first drain outlet 112a is provided exclusively for draining the breeding water. In the case of Figure 8, the first drain outlet 112a is provided at point D, which is the middle in the y-axis direction and the furthest in the negative x-axis direction at the bottom of the aquarium 110. The second drain outlet 112b is provided at point C within the exclusion area 120, as described above. The second drain outlet 112b not only drains the breeding water but also debris that has accumulated in the exclusion area 120. Both the breeding water and debris discharged from the first drain outlet 112a and the second drain outlet 112b flow into the physical filter 140.

[0058] Second drain outlet 112b is provided with a valve 129. Normally, valve 129 provided on second drain outlet 112b is closed. That is, when the valve is closed, breeding water, garbage, and aquatic organisms 101 (shrimp) are not discharged from second drain outlet 112b.

[0059] A camera 130 is provided directly above the second drain outlet 112b. The valve 129 and the camera 130 are connected to a discharge control device 200 (described later) via a communication network 131. The camera 130 captures images of the exclusion area 120 including the second drain outlet 112b (valve 129). The captured images are transmitted to the discharge control device 200 at regular time intervals.

[0060] The discharge control device 200 recognizes debris from the captured image and determines whether debris is trapped in the second drain outlet 112b (valve 129). As will be described in detail later, the discharge control device 200 opens the valve 129 when it determines that debris has trapped. When the valve 129 is opened, the rearing water and debris trapped in the second drain outlet 112b (valve 129) are discharged. When the discharge control device 200 determines that the debris has been successfully discharged, it closes the valve 129 again. Recognizing debris from captured images is possible by applying known technology.

[0061] FIG. 9 is a functional block diagram of the emission control device 200. As shown in FIG. It is assumed that the emission control device 200 is a general-purpose computer such as a laptop PC. Each block described below does not represent a hardware configuration, but represents a functional block.

[0062] The discharge control device 200 includes an image acquisition unit 210 , a retention determination unit 220 , and a discharge control unit 230 . The image acquisition unit 210 acquires the captured image transmitted from the camera 130 in the water tank 110. The retention determination unit 220 determines whether or not debris has accumulated in the second drain outlet 112b (valve 129) based on the captured image acquired by the image acquisition unit 210. More specifically, for example, it is assumed that the ratio of the area of debris to the area of the second drain outlet 112b (valve 129) in the captured image reaches a predetermined value or more. At this time, the retention determination unit 220 determines that debris has accumulated in the second drain outlet 112b (valve 129). The retention determination unit 220 instructs the discharge control unit 230 to open the valve 129. The discharge control unit 230 receives the instruction from the retention determination unit 220 and opens the valve 129.

[0063] While the valve 129 is open, the discharge of debris and breeding water from the second drain outlet 112b and the capture of images by the camera 130 continue. For example, suppose that the ratio of the area of debris reflected in the captured image to the area of the second drain outlet 112b (valve 129) falls below a predetermined value. At this time, the retention determination unit 220 determines that the debris has been successfully discharged. The retention determination unit 220 instructs the discharge control unit 230 to close the valve 129. The discharge control unit 230 receives the instruction from the retention determination unit 220 and closes the valve 129. In this way, in the aquarium 110 of the third embodiment, debris is discharged only when debris is accumulated in the second drain outlet 112b (valve 129).

[0064] In summary, in the third embodiment, a vertical swirling flow is generated in the aquarium 110 by the wind discharged from the air blower duct 127, and the bottom periphery of the aquarium 110 becomes a retention area. In the third embodiment, a part of the retention area is set as the exclusion area 120. The aquarium 110 is provided with a first drain outlet 112a dedicated to draining water, as well as a second drain outlet 112b for discharging breeding water and debris into the exclusion area 120. A valve 129 that is normally closed is provided in the second drain outlet 112b. A camera 130 is provided directly above the second drain outlet 112b. The valve 129 and camera 130 are connected to the discharge control device 200. The camera 130 captures images of the exclusion area 120. The discharge control device 200 determines whether debris has accumulated based on the captured images. When the discharge control device 200 determines that debris has accumulated, the valve 129 is opened and the debris (breeding water) is discharged. According to this method, the breeding water is constantly circulated via the first drain outlet 112a, and waste can be automatically discharged from the second drain outlet 112b only when necessary. In addition, since the second drain outlet 112b is normally closed, the risk of the aquatic organisms 101 being discharged outside the aquarium 110 can be reduced.

[0065] As in the first and second embodiments, the electrode 162 may be provided in a manner that circumscribes the exclusion area 120. Providing the electrode 162 in addition to the valve 129 more reliably prevents the aquatic organisms 101 (shrimp) from being discharged. In the third embodiment, providing a strainer in the first drain outlet 112a enables the breeding water to circulate while preventing the aquatic organisms 101 from being discharged. Furthermore, when debris accumulates in the second drain outlet 112b (valve 129), the valve 129 is opened. In other words, while the valve 129 is closed, the aquatic organisms 101 are not discharged from the second drain outlet 112b. Therefore, there is no need to constantly energize the electrode 162 to form an electrical barrier, which reduces power consumption and electrode wear.

[0066] [Variations] In this embodiment, the water flow of the breeding water is used to generate the exclusion area 120 and collect debris. As a variation, an underwater structure 132 may be installed at the bottom of the aquarium 110 to generate stagnation in the water flow and collect debris.

[0067] Figure 10 shows a side view of an aquarium 110 in which breeding water flows in one direction. A rectangular parallelepiped underwater structure 132 is provided at the bottom of the aquarium 110. In this case, stagnation of the water flow occurs in the shadow of the downstream side of the underwater structure 132 in the aquarium 110, making it easy for debris to accumulate. Therefore, the location where the water flow stagnates is set as an exclusion zone 120. By providing a drainage outlet 112 in the exclusion zone 120, debris that has drifted ashore in the exclusion zone 120 can be discharged out of the aquarium 110.

[0068] The underwater structure 132 is not limited to a rectangular parallelepiped object. For example, it may be a pipe laid at the bottom of the water tank 110, such as the drain pipe 117 or the water supply pipe 118. Alternatively, it may be a device such as a heater and a rectifier.

[0069] Figure 11 is a schematic diagram showing an example of the installation of the drain outlet 112. In this embodiment, the drain outlet 112 may be installed not only at the bottom of the aquarium 110 as shown in Figure 11(a), but also depending on the situation of the installation location of the aquarium 110.

[0070] For example, the drain outlet 112 may be provided on the side wall 110a of the aquarium 110 (Fig. 11(b)). Alternatively, an L-shaped drain pipe 117 may be provided inside the aquarium 110, and the breeding water may be sucked out sideways from the drain outlet 112 (Fig. 11(c)) or upwards (Fig. 11(d)).

[0071] 12 is a schematic diagram showing examples of the shapes of the drain pipe 117 and the water tank 110. The shapes of the drain pipe 117 and the water tank 110 may be modified to allow for efficient collection and discharge of waste.

[0072] For example, in FIG. 12(a), the lower end of the drain pipe 117 penetrates the bottom of the aquarium 110 and is connected to the upstream piping of the physical filter 140. The drain pipe 117 has a double-pipe structure including an inner pipe 134 and an outer pipe 135, which are coaxially arranged. The outer pipe 135 has a height similar to that of the inner pipe 134 and has multiple openings 136 on the side of the lower end. When such a drain pipe 117 is used, if drainage occurs due to overflow in the inner pipe 134, the breeding water present in the passage between the inner pipe 134 and the outer pipe 135 is sucked up. This modification utilizes this phenomenon to guide debris accumulated at the bottom of the aquarium 110 to the drain outlet 112.

[0073] 12(b), a water tank 110 has a recess 137 at the center of the bottom. A drain outlet 112 is provided at the center of the recess 137. When the center of the bottom of the water tank 110 is set as the exclusion area 120, debris that has washed up on the exclusion area 120 may be further allowed to sink into the recess 137, making it easier to discharge the debris from the drain outlet 112.

[0074] The bottom of the water tank 110 in Figure 12(c) is formed in a cone shape. Debris tends to collect in the deepest part of the bottom of the cone-shaped water tank 110 (the center of the bottom). For this reason, the center of the bottom of the water tank 110 is set as the exclusion area 120, and a drain outlet 112 is provided therein. In this way, by allowing the debris to slide down toward the center of the bottom of the water tank 110, it may be possible to make it easier to discharge the debris from the drain outlet 112.

[0075] As shown in Figure 12(d), it is assumed that the bottom periphery E of the water tank 110 is set as the exclusion area 120. In this case, a slope is provided toward the bottom periphery E, and a drain outlet 112 is provided at the bottom end of the slope. The slope may allow the debris to slide down, making it easier to discharge the debris from the drain outlet 112.

[0076] In the present embodiment, the aquarium 110 is described as not being provided with a strainer at the drain outlet 112, but a strainer with a wide mesh may be provided. In this case, the mesh size should not be narrower than the overall width of the cross section of the aquatic organism 101 (shrimp).

[0077] In the aquarium 110 of this embodiment, electrodes 162 are provided around the exclusion area 120 as a medium (exclusion section) that repels the aquatic organisms 101 (shrimp) so that the aquatic organisms 101 are not discharged from the drain outlet 112. As a modification, a light-emitting body, a sound-producing body, a device that generates bubbles, or the like may be provided instead of the electrodes 162. Alternatively, a device that generates, for example, a smell or sound that the aquatic organisms 101 like may be provided as a medium (exclusion section) for attracting the aquatic organisms 101 to a location other than the exclusion area 120.

[0078] In the first embodiment, as a preparation before rearing the aquatic organisms 101 (shrimp), a retention area is identified based on the flow velocity and flow direction of the rearing water measured at each measurement point 119 using a current meter, a current direction meter, etc., and the exclusion area 120 is set. As a modification, the retention area may be identified based on other methods.

[0079] For example, weight sensors (not shown) are provided at multiple locations on the bottom of the aquarium 110. When a water current is generated in the breeding water in the aquarium 110, the weight of debris accumulated on the weight sensors is measured. At this time, a location where the weight of debris measured by the weight sensor is equal to or greater than a predetermined value may be identified as an accumulation area. Alternatively, a water current may be generated in the breeding water in advance as a demonstration experiment, and a location where debris is actually confirmed to be accumulated visually may be identified as an accumulation area. An accumulation area may also be identified based on the results of predictions of the flow speed and flow direction in the aquarium 110 using fluid analysis software.

[0080] In the first embodiment, the electrodes 162 are provided along the exclusion area 120. It has been described that an electrical barrier is formed to surround the exclusion area 120, thereby preventing the intrusion of aquatic organisms 101. As a modification, the voltage and frequency applied to the electrodes 162 may be changeable depending on the type of aquatic organism 101.

[0081] In the second embodiment, the grooves 125 and protrusions 126 are provided on the bottom of the water tank 110. As a modification, the grooves 125 and protrusions 126 may be provided on a circular water tank 110 as in the first embodiment, or on a rectangular parallelepiped water tank 110 as in the third embodiment.

[0082] The grooves 125 and protrusions 126 described in the second embodiment may be provided at equal intervals on the bottom of the aquarium 110, or may be provided at varying intervals. For example, the intervals may be shorter near the downstream side of the exclusion area 120, and gradually longer as the fish move downstream toward the other exclusion area 120. According to this method, the food 104 immediately after feeding can remain in the breeding water for a long time, and the food 104 that has been fed for some time (residual food 103) can be quickly moved toward the exclusion area 120.

[0083] In the second embodiment, the depth of the groove 125 is shallower than the length of the bait 104, and the height of the protrusion 126 is shorter than the length of the bait 104. The depth of the groove 125 and the height of the protrusion 126 may be changed depending on conditions such as the flow rate of the rearing water. For example, when the flow rate of the rearing water is fast, feeding frequency is low, or the density of aquatic organisms 101 (shrimp) in the rearing water is high, the bait 104 needs to be larger to ensure that the aquatic organisms 101 ingest the bait 104. As the bait 104 becomes larger, the sizes of the groove 125 and the protrusion 126 also need to be relatively larger. In such a case, the average movement speed of the bait 104 may be confirmed in advance through a demonstration experiment, and the optimal sizes of the groove 125 and the protrusion 126 may be determined based on the results.

[0084] In the third embodiment, the aquarium 110 is provided with two drain outlets 112. It has been described that the breeding water (debris) discharged from the first drain outlet 112a and the second drain outlet 112b both flow into the physical filter 140. As a modified example, only the drain pipe 117 extending from the first drain outlet 112a, which is dedicated to draining the breeding water, may be connected to the circulation path 111 consisting of the physical filter 140, the biological filtration tank 141, and the first pump 113. The drain pipe 117 extending from the second drain outlet 112b provided in the exclusion area 120 may be connected to a second physical filter (not shown) separate from the physical filter 140. In other words, the debris in the aquarium 110 may be captured in a drainage path separate from the breeding water circulation path 111.

[0085] For example, a strainer is provided at the first drain outlet 112a, and small debris is collected in the physical filter 140 on the circulation path 111. A second physical filter on a drainage path separate from the circulation path 111 collects large debris that cannot pass through the strainer. In this manner, debris is collected in the physical filter 140 and the second physical filter, respectively, and can be separated. Furthermore, when the physical filter 140 and the second physical filter are provided, it is easier to collect only the molted shells 102 in the second physical filter, for example, compared to when only the physical filter 140 is provided. In other words, processing into by-products can be easily carried out.

[0086] In the third embodiment, the valve 129 is provided in the second drain outlet 112b. As a modification, the valve 129 may be provided in the drain pipe 117 extending from the second drain outlet 112b. That is, the second drain outlet 112b may be left open, and the discharge of waste may be controlled by opening and closing the valve 129 provided in the drain pipe 117. In this case, to prevent the discharge of aquatic organisms 101 (shrimp), an electrode 162 may be provided in a manner circumscribing the exclusion zone 120 including the second drain outlet 112b. Alternatively, a valve may be provided in the second drain outlet 112b in addition to the drain pipe 117, or a medium that repels aquatic organisms 101, such as a light-emitting body, a sound-producing body, or a bubble-generating device, may be provided in the second drain outlet 112b instead of the electrode 162.

[0087] In the third embodiment, it is assumed that the ratio of the area of the second drain outlet 112b (valve 129) in the captured image showing the garbage reaches or exceeds a predetermined value. At this time, the accumulation determination unit 220 of the discharge control device 200 opens the valve 129 installed in the drain outlet 112 to discharge the garbage. As a modified example, the accumulation determination unit 220 determines whether or not an aquatic organism 101 (shrimp) is present above the second drain outlet 112b (valve 129) in the captured image. When the accumulation determination unit 220 determines that no shrimp is present above the second drain outlet 112b (valve 129), the accumulation determination unit 220 may cause the discharge control unit 230 to open the valve 129.

[0088] The present invention is not limited to the above-described embodiments and modifications, and the components can be modified without departing from the spirit of the invention. Various inventions can be formed by appropriately combining multiple components disclosed in the above-described embodiments and modifications. Furthermore, some components can be omitted from all the components shown in the above-described embodiments and modifications. [Explanation of symbols]

[0089] 100 aquaculture device, 101 aquatic organisms, 102 molted shells, 103 residual feed, 104 feed, 110 aquarium, 110a side wall, 110b corner, 111 circulation path, 112 drain outlet, 112a first drain outlet, 112b second drain outlet, 113 first pump, 114 water supply inlet, 115 second pump, 116 third pump, 117 drain pipe, 118 water supply pipe, 118a branch pipe, 119 measuring point, 120 exclusion area, 121 partition plate, 122 waterway, 123 first area, 124 second area, 125 groove, 126 protrusion, 127 air duct, 128 air duct, 129 valve, 130 camera, 131 communication network, 132 underwater structure, 134 Inner pipe, 135 outer pipe, 136 opening, 137 depression, 140 physical filter, 141 biological filtration tank, 142 foam separation device, 143 denitrification tank, 144 oxygen supply device, 150 feeding device, 151 feeding pipe, 152 feeding port, 160 power supply device, 161 conductive cable, 162 electrode, 200 discharge control device, 210 image acquisition unit, 220 retention determination unit, 230 discharge control unit

Claims

1. an aquarium for raising aquatic organisms; a water supply unit that supplies breeding water to the aquarium; a drainage section that discharges breeding water from the aquarium through a drainage port formed in the aquarium; An aquaculture device comprising an exclusion section that prevents aquatic organisms from invading a designated exclusion area set in the aquarium by applying in water both or one of a medium that repels aquatic organisms and a medium that attracts the aquatic organisms.

2. A water flow generated in the water tank forms a region in the water tank where the flow velocity is relatively high and a region in the water tank where the flow velocity is relatively low, The aquaculture device according to claim 1 , wherein the exclusion area is set in an area where the flow velocity is relatively slow.

3. a water flow generated in the water tank forms an area in which unwanted objects generated in the water tank accumulate; The aquaculture device according to claim 1 , wherein the exclusion area is set in an area where the unwanted objects remain.

4. The aquaculture device according to claim 1 , wherein the exclusion area is set at the drain outlet.

5. A feeding unit that puts food for the aquatic organisms into the aquarium, The specific gravity of the food is equal to or greater than the specific gravity of the breeding water in the aquarium, 2. The aquaculture device according to claim 1, wherein the bottom of the tank is formed with grooves and / or protrusions for impeding the movement of the introduced feed.

6. The aquatic organism food is a solid food formed as a mass, The aquaculture device according to claim 5 , wherein the grooves are shallower than the length of the solid bait, and the protrusions are protrusions having a height shorter than the length of the solid bait.

7. A feeding unit that puts food for the aquatic organisms into the aquarium, The water tank is an elliptical water tank having a partition plate extending in the longitudinal direction at the center, The aquaculture device described in claim 1, wherein the feeding unit injects food for the aquatic organisms at a point downstream of a first retention area in which unwanted objects generated in the aquarium accumulate, upstream of a second retention area in which the unwanted objects accumulate, and closer to the first retention area than the second retention area.

8. The aquaculture device according to claim 1 , wherein the exclusion unit generates an electric field in the exclusion area as a medium for repelling the aquatic organisms.

9. a first drain outlet and a second drain outlet are formed as the drain outlets, the drainage unit uses a pump to drain the breeding water in the aquarium from both the first drain outlet and the second drain outlet; The aquaculture device of claim 1 , wherein the second drain outlet is formed in the exclusion area.

10. a camera for capturing an image of the second drain outlet; a retention determination unit that determines the amount of unwanted objects retained in the second drain outlet from the image captured by the camera, The second drain port or the drain portion is configured to be openable and closable, The aquaculture device according to claim 9 , wherein the drainage section discharges the unwanted objects from the second drainage outlet when a predetermined discharge condition is met regarding the amount of unwanted objects accumulated.

11. The aquaculture device of claim 1 , wherein the aquatic organisms are crustacean organisms.

Images