Breeding device

Abstract

To provide a technology capable of efficiently collecting and removing unnecessary objects in an aquarium. [Solution] The aquaculture device comprises an aquarium for raising aquatic organisms, a water supply section which supplies breeding water to the aquarium, a drainage section which discharges the breeding water in the aquarium through a drain formed in the aquarium, and an exclusion section which 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.

Description

[Technical field]

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

[0002] As the 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 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 affected by 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] JP 2006-129862 A Summary of the Invention [Problem to be solved by the invention]

[0004] Shrimp and other crustaceans are among the aquatic organisms that are cultivated in land-based aquaculture. In addition to molted shells, unnecessary objects such as feces, leftover food, and dead shrimp (hereafter referred to as "garbage") are generated in shrimp breeding tanks. In land-based shrimp aquaculture, the water in the breeding tanks (hereafter referred to as "breeding water") is purified and circulated to keep the water clean. To prevent shrimp from being discharged along with the breeding water, the drain is usually fitted 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 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 outside the tank. Therefore, strainers are frequently cleaned at land-based shrimp farming sites. As such, under current circumstances, it takes a considerable amount of effort to remove waste from tanks in which 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 section which supplies breeding water to the aquarium, a drainage section which discharges the breeding water in the aquarium through a drain outlet formed in the aquarium, and an exclusion section which 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. Effect of the Invention

[0008] According to the present invention, a technology is provided that can efficiently collect and remove unwanted objects from within an aquarium. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of an aquaculture device in a first embodiment. [Diagram 2] FIG. 2 is a perspective view showing the structure of the water tank and its surroundings in the first embodiment. [Diagram 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. [Diagram 5]FIG. 4 is a third plan view of the water tank in the first embodiment. [Figure 6] FIG. 11 is a schematic diagram of an aquaculture device in a second embodiment. [Figure 7] FIG. 11 is a side view showing the bottom structure of the water tank in the second embodiment. [Figure 8] FIG. 11 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. 2 is a side view showing the bottom structure of the tank in which the underwater structure is provided. [Figure 11] Fig. 11(a) is a schematic diagram of an aquarium with a drain outlet at the bottom. Fig. 11(b) is a schematic diagram of an aquarium with a drain outlet on the side wall. Fig. 11(c) is a schematic diagram of an aquarium with an L-shaped drain pipe with a drain outlet facing sideways. Fig. 11(d) is a schematic diagram of an aquarium with an L-shaped drain pipe with a drain outlet facing downwards. [Figure 12] Fig. 12(a) is a schematic diagram of an aquarium with a drain outlet having a double pipe structure. Fig. 12(b) is a schematic diagram of an aquarium with a depression and a drain outlet in the center of the bottom. Fig. 12(c) is a schematic diagram of an aquarium with a drain outlet in the deepest part of the bowl-shaped bottom. Fig. 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 PREFERRED EMBODIMENTS

[0010] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. First, as a first embodiment, an overview of debris collection and removal in a circular aquarium will be described. Next, as a second embodiment, an overview of debris collection and removal in a raceway-type aquarium will be described. Furthermore, as a third embodiment, an overview of debris collection and removal 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 cultivating 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. The breeding water circulates through the circulation path 111 by driving the first pump 113. 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 methods. The free-flowing method is a method in which water is taken from the sea or river by a pump and supplied to the water tank 110, and dirty water is discharged from the water tank 110, that is, the water is kept clean by water exchange. In contrast, the closed circulation method has a circulation path 111 for reusing the water stored in the water tank 110, and keeps the water clean by passing it through a filter tank installed in the circulation path 111. As a compromise between the free-flowing and closed circulation methods, there is also a semi-circulation method in which the water is circulated while part of it is exchanged. In this embodiment, the closed circulation method is adopted among land-based aquaculture, thereby eliminating the introduction of pathogens from outside and reducing seasonal factors that affect the water temperature. 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 may be a saltwater fish or a freshwater fish. The aquatic organism 101 may be a crustacean or shellfish other than shrimp, or other fish and shellfish. The composition of the breeding 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 water tank 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 garbage, such as the molted shells 102 and the remaining food 103, discharged from the drain outlet 112.

[0015] Toxic ammonia is generated in the aquarium 110 due to the metabolic activity of the 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 the 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 adsorbs organic matter contained in the water into foam, causes the organic matter to float, and separates the organic matter, 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 drive of the third pump 116, and is returned to the biological filtration tank 141. The denitrification tank 143 holds denitrifying bacteria, and reduces the nitrate contained in the filtered water to nitrogen gas and releases 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 when the aquatic organism 101 is a shrimp, the third pump 116 and the denitrification tank 143 may not be provided.

[0018] The aquaculture device 100 is further provided with an oxygen supplying device 144, a feeding device 150, and a power supply device 160. The oxygen supplying 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. Although details will be described later, a weak current is passed from the power supply device 160 to the electrode 162 to inhibit aquatic organisms 101 from invading the area surrounded by the electrode 162. The electrode 162 functions as an "exclusion part."

[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 supplying device 144 and the feeding device 150 are omitted from the illustration.

[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 a conductive cable 161 are provided around the drain outlet 112. Although 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 outside 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 rearing water is discharged from the water supply pipe 118, a unidirectional water flow centered directly above the drain port 112 is generated (see the arrow in the figure). In other words, a circular water flow, i.e., a swirling flow of rearing water, is generated in the aquarium 110. In the case of FIG. 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, the aquatic organism 101, the molted shell 102, the remaining food 103, the drain port 112, the oxygen supply device 144, the feeding device 150, and the electrodes 162 are omitted from Fig. 3. Here, the setting of the exclusion area 120, which is carried out as a preparation before raising the aquatic organism 101 (shrimp) in the aquarium 110, will be explained. 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, there are areas in the aquarium 110 where the flow speed of the breeding water is fast and slow. More specifically, in the case of the first embodiment, the flow speed is faster as it approaches the side wall 110a of the aquarium 110, and the flow speed is slower as it approaches the center P. In addition, due to the centrifugal force generated by the swirling flow of the breeding water and the 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. In this way, due to the difference in the swirling flow speed and the water flow generated in conjunction with the swirling flow, garbage tends to accumulate near the bottom of the aquarium 110 and around the center P. Hereinafter, the area where garbage tends to accumulate is also called an accumulation area.

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

[0027] More specifically, a situation in which a flow meter is installed at each measurement point 119 to measure the flow speed of the rearing water and an area with a relatively slow flow speed 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 speed and the measurement point 119 adjacent to that measurement point 119. Alternatively, an average flow speed is calculated from the flow speeds measured at all measurement points 119. At this time, the area including the measurement point 119 with a flow speed lower than the average flow speed may be identified as the retention area. Using this method, the retention area in the aquarium 110 is identified.

[0028] The measurement points 119 may be set at any positions in the water tank 110. In Fig. 3, the center P is used as a reference point, and the 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-119d adjacent to measurement point 119P in the vertical and horizontal directions, more specifically, the region inside the circle circumscribing measurement points 119a-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. It is assumed that the measurement results of the flow direction meter at each measurement point 119 reveal that the direction of the water flow of the breeding water 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 current 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, the oxygen supply device 144, the feeding device 150, and the electrodes 162 are omitted from FIG.

[0032] As described above, as a swirling flow occurs, the area around the center P of the aquarium 110 becomes a retention area, whereby debris such as molted shells 102 and remaining food 103 accumulate. 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 supplying device 144 and the feeding device 150 are omitted in FIG.

[0035] In order to efficiently collect waste and quickly discharge it while reducing the above-mentioned risks, when raising aquatic organisms 101 (shrimp), an electrode 162 is installed in a manner that circumscribes the exclusion zone 120 as shown in FIG. 5. A weak current is applied from a power supply device 160 to the electrode 162. An electric field is generated between adjacent electrodes 162 along the exclusion zone 120. In other words, an electric barrier is formed so as to surround the exclusion zone 120. Since the aquatic organisms 101 have a nature of aversion to electricity, this method can prevent the aquatic organisms 101 from entering the exclusion zone 120. It is possible to apply a known technology to apply a weak current to the electrode 162 and keep the aquatic organisms 101 away from the exclusion zone 120 (see Patent Documents 1 and 2).

[0036] Meanwhile, trash such as molted shells 102 and remaining food 103 pass through the gaps between the electrodes 162 and wash up in the exclusion area 120. The trash that washes up in the exclusion area 120 is discharged outside the aquarium 110 from 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 trash and the aquatic organisms 101 that are generated in the breeding water of the aquarium 110.

[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, since garbage accumulates in the strainer, cleaning the strainer is a burden for the worker. In the first embodiment, the drain outlet 112 is provided in an area (retention area) in the aquarium 110 where garbage is likely to accumulate, and the retention area is set as the exclusion area 120. Electrodes 162 are provided around the exclusion area 120, and an electric barrier is generated by passing a weak current through them. With this method, shrimp do not approach the drain outlet 112, so that it is possible to prevent shrimp from being discharged and discharge garbage from the aquarium 110 without using a strainer.

[0038] [Second embodiment] FIG. 6 is a schematic diagram of an aquaculture device 100 in the second embodiment. In the second embodiment, a so-called raceway type water tank 110 is used. 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. A 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 a side wall 110a of the aquarium 110. The water supply pipe 118 extends inside the aquarium 110 and branches into a plurality of pipes (branch pipes 118a). The open end (i.e., water supply port 114) of each branch pipe 118a faces the downstream side of the aquarium 110, and breeding water is discharged toward the downstream side, thereby generating the above-mentioned unidirectional water flow.

[0040] It is known that near the upstream end of the water channel 122a (122b), that is, in the area along the partition plate 121 near the downstream end of each corner portion 110b, the water flow is likely to change direction at the corner portion 110b, causing local vortexes and making it easy for debris to accumulate (see Patent Document 3). That is, since the location where the vortex occurs becomes the retention area, the 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 a range of one-fifth of the upstream side of the water channel 122a (122b) on the partition plate 121. In addition, 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, there is a possibility that fresh bait 104 immediately after feeding, in other words, may be discharged from the drain outlet 112 early. For example, suppose feeding is performed in the first area 123 located on the opposite side of the partition plate 121 from the exclusion area 120. In this case, the bait 104 will immediately wash up in 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] 6, in the second embodiment, feeding is carried out in a second region 124a (124b) located immediately downstream of and behind the exclusion region 120a (120b) in the waterway 122a (122b). Hereinafter, the second region 124a located immediately behind the exclusion region 120a will be described.

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

[0044] Also, a straight line is set that is perpendicular to the side wall 110a and tangent to the exclusion area 120b on the upstream side of the waterway 122. In this case, the perpendicular point with the water tank 110 is set as point Pa3, and the tangent point with the exclusion area 120b is set as point Pa4. The second area 124a is set downstream of the straight line connecting points Pa1 and Pa2, and upstream of the straight line connecting the partition plate 121 and the midpoint (hereinafter referred to as the "area midpoint") Pa5 on the side wall 110a between points Pa1 and Pa3. Note that the straight line connecting the partition plate 121 and the area midpoint Pa5 (hereinafter referred to as the "midline") is set perpendicular to the side wall 110a. Also, the area midpoint Pa5 is set downstream of the exclusion area 120a and upstream of the exclusion area 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 range. More preferably, the second region 124a is set downstream of the line connecting points Pa1 and Pa2 and upstream of the middle line, within the upstream half range.

[0045] In the second area 124a including point Pa1, a feeding pipe 151a extends from the side wall 110a of the aquarium 110 in the width direction of the waterway 122a. More specifically, the upstream boundary line in the width direction of the feeding pipe 151a overlaps with the straight line connecting points Pa1 and Pa2. The feeding pipe 151a is provided with multiple feeding ports 152. The food 104 stored in the feeding device 150 is fed from the feeding port 152 via the feeding pipe 151a. The fed food 104 drifts counterclockwise in the waterway 122. Similarly, a feeding pipe 151b is provided in the second area 124b immediately downstream of the exclusion area 120b, and feeding is performed.

[0046] The position where the bait 104 falls into the breeding water, in other words, the position where the bait 104 is actually fed, may be tangent to the line connecting the points Pa1 and Pa2. For example, the upstream boundary in the width direction of the feeding port 152 may overlap with the line connecting the points Pa1 and Pa2. The bait 104 may be thrown into the air and dropped at a position tangent to the line connecting the points Pa1 and Pa2 for feeding. Alternatively, the bait 104 may be mixed in the breeding water in advance, the breeding water may be supplied at a position tangent to the line connecting the points Pa1 and Pa2, and the bait 104 may be dispersed for feeding.

[0047] According to this method, it is possible to buy time before fresh bait 104 is 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 aquatic organisms 101 will ingest all bait 104 before it is discharged from drain outlet 112, it is possible to reduce waste of bait 104 that is discharged early.

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

[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 fed 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 feeding.

[0050] In the aquarium 110 in 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 the bait 104 is fed in the second area 124, it stays in the breeding water for a longer period of time than in the first area 123. Therefore, it is possible to extend the time that the bait 104 is ingested by the aquatic organisms 101.

[0051] One possible method for further extending the time that the aquatic organisms 101 consume the bait 104 is to change the bottom structure 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 may be provided in a random order. Only the grooves 125 or only the protrusions 126 may be provided.

[0052] The fed bait 104 repeats the movement of being captured by the groove 125 or the protrusion 126 and being swept away by the water current. 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. Therefore, the bait 104 does not remain captured in the groove 125 or the protrusion 126 for an excessively long time in the same place, but moves downstream at appropriate time intervals. According to this method, the average moving speed of the bait 104 can be slowed down compared to when the bottom of the aquarium 110 is flat. Therefore, it is easier for the aquatic organism 101 to ingest all of the bait 104.

[0053] In summary, in the raceway type water tank 110, garbage tends to gather at the location where a local vortex occurs due to a change in the direction of the water flow at the corner portion 110b. Therefore, a drain outlet 112 is provided at the location 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 the exclusion area 120. This makes it possible to extend the time until the bait 104 is discharged from the drain outlet 112. In addition, a groove 125 and a protrusion 126 are provided at the bottom of the water tank 110. This makes it possible to slow down the average moving speed of the bait 104. According to these methods, it is possible to prevent the bait 104 from being discharged early, and to give the aquatic organisms 101 a sufficient opportunity 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 Fig. 8 employs a rectangular parallelepiped water tank 110. In the following description of the water tank 110, the left-right direction is the x-axis direction, the front-back direction is the y-axis direction, and the up-down direction is the z-axis direction. For convenience of explanation, the water supply pipe 118, the oxygen supply device 144, and the feeding device 150 are omitted from Fig. 8.

[0055] An air blower pipe 127 is provided at the diagonal upper part of the aquarium 110 (at the upper part in the positive y-axis direction and the positive z-axis direction of the aquarium 110). Air is blown out from an open end (air blower port 128) of the air blower pipe 127 toward the water surface Wf in the negative y-axis direction and the negative z-axis direction. The air blown out from the air blower port 128 generates a swirling flow of the breeding water centered on the x-axis in the aquarium 110 (see the arrow in the figure). Due to the swirling flow, the garbage in the breeding water gradually accumulates in the peripheral part of the bottom of the aquarium 110 in the positive y-axis direction and the negative z-axis direction, more specifically, around the line connecting point A to point B in FIG. 8. That is, the stagnation area is the area around the line connecting point A and point B. In the third embodiment, a drain outlet 112 is provided at point C, which is the midpoint between point A and point B. Therefore, point C and its surroundings are set as the exclusion area 120.

[0056] In the aquaculture device 100 of the third embodiment, two drainage outlets 112 are provided. As described above, shrimp tend to gather in areas where garbage is likely to accumulate (retention areas). When the drainage outlet 112 is provided in the retention area, there is a high risk that the shrimp will be discharged if the drainage outlet 112 is left open. To avoid this risk, a method of opening the drainage outlet 112 only when a predetermined amount of garbage is accumulated in the exclusion area 120 can be considered. However, when there is only one drainage outlet 112, water is not discharged while garbage is not accumulated, and therefore the culture water is not circulated. Therefore, in the third embodiment, a first drainage outlet 112a and a second drainage 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 in the exclusion area 120, as described above. The second drain outlet 112b drains not only 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 an image of the exclusion area 120 including the second drain outlet 112b (valve 129). The captured image is 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). Although details will be described later, the discharge control device 200 opens the valve 129 when it determines that debris is trapped. When the valve 129 is opened, the breeding 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 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 represents a functional block, not a hardware configuration.

[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 is retained 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 ​​the 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 is retained 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 the waste and rearing water from the second drain outlet 112b and the capture of images by the camera 130 are continuously performed. For example, assume that the ratio of the area of ​​the waste to the area of ​​the second drain outlet 112b (valve 129) in the captured image reaches less than a predetermined value. At this time, the retention determination unit 220 determines that the waste has been 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, the waste is discharged only when the waste 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 pipe 127, and the bottom periphery of the aquarium 110 becomes the retention area. In the third embodiment, a part of the retention area is set as the exclusion area 120. In the aquarium 110, a first drain outlet 112a dedicated to drainage and a second drain outlet 112b for discharging the breeding water and garbage into the exclusion area 120 are provided. 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 the camera 130 are connected to the discharge control device 200. The camera 130 captures an image of the exclusion area 120. The discharge control device 200 determines whether garbage is retained based on the captured image. When the discharge control device 200 determines that garbage is retained, the valve 129 is opened and the garbage (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. If the electrode 162 is provided in addition to the valve 129, discharge of the aquatic organisms 101 (shrimp) can be more reliably prevented. In the third embodiment, if a strainer is provided in the first drain outlet 112a, the breeding water can be circulated while preventing discharge of the aquatic organisms 101. In addition, when garbage is accumulated 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, it is not necessary to constantly energize the electrode 162 and form an electrical barrier, so that power consumption and wear of the electrode can be suppressed.

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

[0067] 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, in the aquarium 110, stagnation of the water flow occurs in the shadow of the downstream side of the underwater structure 132, and garbage tends to accumulate. Therefore, the place where the water flow stagnates is set as an exclusion area 120. By providing a drainage outlet 112 in the exclusion area 120, it becomes possible to discharge garbage that has washed up in the exclusion area 120 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 on 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 baffle.

[0069] Fig. 11 is a schematic diagram showing an example of installation of a drain outlet 112. In this embodiment, the drain outlet 112 may be provided not only at the bottom of the aquarium 110 as shown in Fig. 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 in a 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 efficiently collect and discharge the garbage.

[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 coaxially. 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 rearing water present in the passage between the inner pipe 134 and the outer pipe 135 is sucked up upward. In this modified example, this phenomenon is utilized to guide debris accumulated at the bottom of the aquarium 110 to the drain outlet 112.

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

[0074] In the aquarium 110 of Fig. 12(c), the bottom is formed in a cone shape. Debris tends to collect in the most depressed part of the bottom of the cone-shaped aquarium 110 (the center of the bottom). For this reason, the center of the bottom of the aquarium 110 is set as the exclusion area 120, and a drain outlet 112 is provided therein. In this way, the debris may be made to slide down toward the center of the bottom of the aquarium 110, making it easier to discharge the debris from the drain outlet 112.

[0075] 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 be used to make it easier for the debris to be discharged from the drain outlet 112 by allowing the debris to slide down.

[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 is not narrower than the overall width of the cross section of the aquatic organism 101 (shrimp).

[0077] In the aquarium 110 of this embodiment, the 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 112. As a modified example, 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 place 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 specified based on the flow velocity and flow direction of the rearing water measured at each measurement point 119 by a current meter, a current direction meter, etc., and an exclusion area 120 is set. As a modification, the retention area may be specified based on other methods.

[0079] For example, weight sensors (not shown) are provided at multiple locations on the bottom of aquarium 110. When a water current is generated in the breeding water in aquarium 110, the weight of the debris retained on the weight sensors is measured. At this time, a location where the weight of the debris measured by the weight sensor is equal to or greater than a predetermined value may be identified as the retention 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 retained by visual inspection may be identified as the retention area. The retention area may be identified based on the results of predictions of the flow speed and flow direction in aquarium 110 using software for fluid analysis.

[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 the aquatic organisms 101. As a modified example, 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 groove 125 and the protrusion 126 are provided on the bottom of the water tank 110. As a modification, the groove 125 and the protrusion 126 may be provided on a circular water tank 110 as in the first embodiment, or on a rectangular 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 shortened near the downstream side of the exclusion area 120, and gradually increased as the fish move downstream toward the other exclusion area 120. According to this method, the food 104 immediately after feeding can be allowed to remain in the breeding water for a long time, and the food 104 (residual food 103) that has been fed for a long time can be moved quickly 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 according to conditions such as the flow rate of the rearing water. For example, when the flow rate of the rearing water is fast, the feeding frequency is low, or the density of the aquatic organisms 101 (shrimp) in the rearing water is high, the bait 104 needs to be made larger in order to ensure that the aquatic organisms 101 take in 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 moving speed of the bait 104 may be confirmed in advance by a demonstration experiment, and the optimal values ​​of the sizes of the groove 125 and the protrusion 126 may be determined based on the results of the experiment.

[0084] In the third embodiment, the aquarium 110 is provided with two drainage outlets 112. It has been described that the breeding water (debris) discharged from the first drainage outlet 112a and the second drainage outlet 112b both flow into the physical filter 140. As a modified example, only the drainage pipe 117 extending from the first drainage 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 drainage pipe 117 extending from the second drainage 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 can be collected in the physical filter 140 and the second physical filter, respectively, and separated. Furthermore, when the physical filter 140 and the second physical filter are provided, it becomes 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 a by-product can be easily performed.

[0086] In the third embodiment, the valve 129 is provided in the second drain outlet 112b. As a modified example, 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 garbage may be controlled by opening and closing the valve 129 provided in the drain pipe 117. In this case, in order to prevent the discharge of the aquatic organisms 101 (shrimp), the electrode 162 may be provided in a manner that circumscribes the exclusion area 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 the aquatic organisms 101, such as a light-emitting body, a sound-producing body, or a device that generates bubbles, 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 a predetermined value or more. In this case, the retention 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 retention determination unit 220 determines whether or not there is an aquatic organism 101 (shrimp) above the second drain outlet 112b (valve 129) in the captured image. When the retention determination unit 220 determines that there is no shrimp above the second drain outlet 112b (valve 129), the retention 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-mentioned embodiment and modified examples, and the components can be modified without departing from the gist of the present invention. Various inventions can be formed by appropriately combining multiple components disclosed in the above-mentioned embodiment and modified examples. In addition, some components can be deleted from all the components shown in the above-mentioned embodiment and modified examples. [Explanation of symbols]

[0089] 100 aquaculture device, 101 aquatic organisms, 102 molted shells, 103 residual food, 104 food, 110 aquarium, 110a side wall, 110b corner, 111 circulation path, 112 drain, 112a first drain, 112b second drain, 113 first pump, 114 water inlet, 115 second pump, 116 third pump, 117 drain pipe, 118 water inlet, 118a branch pipe, 119 measuring point, 120 exclusion area, 121 partition, 122 waterway, 123 first area, 124 second area, 125 groove, 126 protrusion, 127 air duct, 128 air outlet, 129 valve, 130 camera, 131 communication network, 132 underwater structure, 134 Inner pipe, 135 outer pipe, 136 opening, 137 recess, 140 physical filter, 141 biological filtration tank, 142 foam separator, 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 rearing aquatic organisms; A water supply unit that supplies breeding water to the aquarium; A drainage section that drains the breeding water in the aquarium through a drainage port formed in the aquarium; and an exclusion unit that applies a medium that repels aquatic organisms and / or a medium that attracts aquatic organisms in water to suppress the aquatic organisms from invading a predetermined exclusion area set in the aquarium. The aquaculture device, wherein the exclusion section generates an electric field in the exclusion area as a medium for repelling 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 feeds the aquatic organisms into the tank, 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 bait.

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 food, and the protrusions are protrusions having a height less than the length of the solid food.

7. A feeding unit that feeds the aquatic organisms into the tank, 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 section injects food for the aquatic organisms at a point downstream of a first retention area in which unwanted matter generated in the aquarium accumulates and upstream of a second retention area in which the unwanted matter accumulates, and closer to the first retention area than the second retention area.

8. A first drainage port and a second drainage port are formed as the drainage port, the drainage unit drains the breeding water in the aquarium from both the first drainage outlet and the second drainage outlet by a pump; The aquaculture device of claim 1 , wherein the second drain outlet is formed in the exclusion area.

9. A camera for capturing an image of the second drain outlet; and a retention determination unit that determines an amount of unwanted objects retained in the second drain outlet from an image captured by the camera, The second drain outlet or the drain portion is configured to be openable and closable, The aquaculture device according to claim 8 , wherein the drainage section drains the unnecessary objects from the second drainage outlet when a predetermined discharge condition is satisfied regarding the amount of the unnecessary objects accumulated therein.

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

Images