Fish handling structure for a recirculation aquaculture system

Abstract

A fish handling structure for use in a recirculation aquaculture system includes a tank having a tank wall, wherein the tank has an interior water flow channel defining an infinite loop.

Description

[0001] Attorney Docket No. 70419-WO-PCT

[0002] TITLE FISH HANDLING STRUCTURE FOR A RECIRCULATION AQUACULTURE SYSTEM

[0003] RELATED APPLICATIONS

[0004]

[0001] This application claims priority to United States Provisional Application No. 63 / 720,259 filed under 35 U.S.C. § 111 (b) on November 14, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0005] STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

[0006]

[0002] This invention was made with no government support. The government has no rights in this invention.

[0007] BACKGROUND OF THE INVENTION

[0008]

[0003] This invention relates in general to aquaculture systems. In particular, this invention relates to an improved tank design that supports biosecurity monitoring and fish handling in aquaculture systems.

[0009]

[0004] Streams are characterized by varying flow rates and depths, creating diverse habitats for aquatic organisms. These include shallow riffles with a rocky bottom and a rapid, turbulent flow, shallows with a sandy, muddy, or rocky bottom, rapids with fast-moving water and significant turbulence around rocky obstructions, pools with deeper, slow-moving currents, and channels with a more consistent flow rate and depth in a straight, meandering or braided path, often creating eddies and backwaters. Prized fish commonly used in RAS aquaculture, such as salmon, trout, and amberjack, seek out current conditions that match the animal’s biological preferences. The ability to optimize cultivation of such species Attorney Docket No. 70419-WO-PCT

[0010] depends on providing suitable culture conditions that match a species’ innate habitat preferences.

[0011]

[0005] Many species of fish are motivated to face into and swim against moderate, predictable flows (i.e., positive rheotaxis), primarily as an adaptive survival mechanism. This is beneficial to fish by helping with feeding efficiency (allowing fish to encounter drifting food particles more effectively) and oxygenation (water moving across the gills) helps fish extract oxygen more efficiently to meet respiratory needs. This instinct is so strong that farmed species will even swim against artificial currents, highlighting the evolutionary importance of rheotaxis in their daily life. The goal is to harness this behavior towards providing a more structured flow of fish in a production facility.

[0012]

[0006] Water flow is crucial in a recirculation aquaculture system (RAS) to maintain a healthy and productive environment for the fish. Detailed situational awareness of the conditions that exist in the fish farm provide operators with the information needed to make informed decisions and ensure the optimal health and productivity of the RAS. Real-time access to information is crucial for disease prevention and early detection of health issues, monitoring of water quality, growth, fish behavior, and feeding to help maximize farming conditions, and emergency preparedness to enable agile responses to biosecurity threats, and other emergencies, such as equipment failures or power outages. Unfortunately, current facility designs do not lend themselves to comprehensive real time monitoring of the farmed fish population as they lack the predictability of directing the fish at an ongoing and steady rate into contact with deployed sensor and management systems.

[0013]

[0007] Thus, there is a need in the art for an improved tank design that uses the fish’s natural preferences in order to turn a fish production tank into the equivalent Attorney Docket No. 70419-WO-PCT

[0014] of a conveyor belt system, enhances predictability of fish movement patterns within a RAS facility, and provides an enclosed fish population in a fish farm with structures that mimic natural and preferred features of stream environments and thereby guide the movements of fish in predictable ways.

[0015] SUMMARY OF THE INVENTION

[0016]

[0008] The present invention provides a fish guidance system in which fish are moved through connecting structures, such as water-filled channels that are implemented within a farm’s cultivation tank.

[0017]

[0009] In one embodiment, a fish handling structure for use in a recirculation aquaculture system includes a tank having a tank wall, wherein the tank has an interior water flow channel defining an infinite loop.

[0018]

[0010] Various aspects of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in view of the accompanying drawings.

[0019] BRIEF DESCRIPTION OF THE DRAWINGS

[0020] [Oil] Fig. 1 is a perspective view of a first embodiment of a tank for use in a recirculation aquaculture system in accordance with this invention, and that has an internal water flow channel having the shape of a simple torus.

[0021]

[0012] Fig. 2 is a perspective view of a second embodiment of a tank for use in a recirculation aquaculture system in accordance with this invention, showing two structural water flow channels that are interleaved, wherein each exit connects with the entrance of the other, forming an infinite path.

[0022]

[0013] Fig. 3 is a first side elevational view of the tank illustrated in Fig. 2.

[0023]

[0014] Fig. 4 is a second side elevational view of the tank illustrated in Fig. 2. Attorney Docket No. 70419-WO-PCT

[0024]

[0015] Fig. 5 is a perspective view of a third embodiment of a tank for use in a recirculation aquaculture system in accordance with this invention.

[0025]

[0016] Fig. 6 is a perspective view of a fourth embodiment of a tank for use in a recirculation aquaculture system in accordance with this invention.

[0026]

[0017] Fig. 7 is a perspective view of a fifth embodiment of a tank for use in a recirculation aquaculture system in accordance with this invention showing water inlet tubes and windows.

[0027] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0028]

[0018] The present invention will now be described with occasional reference to the specific embodiments of the invention. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0029]

[0019] Generally, multiple embodiments of a fish handling structure for recirculation aquaculture systems (RAS) are disclosed. The disclosed fish handling structures include structures that are deployed within an aquaculture tank to mimic natural features of stream environments and thereby guide the movements of fish in particular ways. The fish handling structures are designed to enhance data-gathering for situational awareness and bio- security within a facility, such as a fish farm, and to help implement a comprehensive solution in support of enhancing fish health, reducing stress, or increasing efficiency. In addition to fish, the handling structures described herein may be used for other aquatic animals, including but not limited to shrimp. Attorney Docket No. 70419-WO-PCT

[0030]

[0020] Advantageously, the embodiments of the fish handling structures disclosed herein create the ability for the user to enhance predictability of fish movement patterns in a RAS system in order to naturally bring individual fish into suitable points of contact with uncrewed and human-assistive management equipment, and with imaging, sensors, and other assessment devices.

[0031]

[0021] Fish are used to currents in nature. The specific structure of the tanks described herein allow the user to tap into the biology of the fish to make the fish do what the user wants the fish to do, i.e., swim through a current in predictable ways.

[0032]

[0022] Typical tanks may be very large, round or rectangular, and deep, and may have a diameter of about 15 m, and a depth of about 5 m, or if rectangular, may have a similar volume.

[0033]

[0023] The specific shape of the tanks disclosed herein is designed to guide fish in an infinite loop within the tank, thus obligating the fish to move through a sorter at some point, without human interaction or interference.

[0034]

[0024] In one known example, a tank has a conical bottom and a circular current produced. Fish waste will settle in the center of the tank. A standpipe is provided in the center of the tank to remove the waste, such as by suction.

[0035]

[0025] Referring now to the drawings, there is illustrated in Fig. 1 a first embodiment of a tank 10 for use in a recirculation aquaculture system in accordance with this invention. The tank 10 includes a tank wall and an internal structure that creates an internal water flow channel that has the shape of a simple torus and defines an infinite loop. A fish sorter may be attached to the tank 10 at any desired location. Relatively soft, flexible membranes may be mounted within the tank 10 as a liner and to define a water flow channel. Alternatively, the water flow channel may be formed as a tube defining an infinite loop. Such a tube may Attorney Docket No. 70419-WO-PCT

[0036] also be formed from a relatively soft, flexible material. The membranes and / or the tubes may be supported by a scaffolding structure (not shown). Water pressure within the tank 10, and support provided by the affixed scaffolding structure, will allow the membranes and / or the tubes to retain their shape.

[0037]

[0026] Referring now to Figs. 2 through 4, a second embodiment of a tank for use in a recirculation aquaculture system is shown at 20. The tank 20 is configured as a double water flow channel shaped tube and includes a tube wall. When viewed from the top the tank 20 includes four sections S 1 through S4.

[0038] Additionally, the double water flow channel shaped tube defined two water flow circuits Cl and C2. In the illustrated embodiment, the water flow is clockwise, see the arrow A.

[0039]

[0027] In operation, fish within the tank 20 will travel against the flow of water, or counterclockwise. For example, the portion of the flow circuit Cl in section S4 receives water flow from the portion of the flow circuit Cl in section SI via the portion of the flow circuit Cl in section S2 and the portion of the flow circuit Cl in section S. The flow circuit C2 is similar to the circuit Cl and operates in the same manner. At the transition between sections, for example at the transition from section S4 to SI, a lack of a crossover results in an exit of flow circuit Cl in section S4 being fluidly connected to an entrance of the flow circuit C2 in section SI, thus defining an infinite loop within the combined flow circuits Cl and C2.

[0040]

[0028] Referring now to Fig. 5, a perspective view of a third embodiment of a tank for use in a recirculation aquaculture system is shown at 30. The tank 30 has a closed tubular shape such that an entrance of the tube is connected to an exit of the tube, includes a tube wall, and the closed tube is folded onto itself such that a water flow channel therein defines infinite loop. Attorney Docket No. 70419-WO-PCT

[0041]

[0029] Referring now to Fig. 6, a perspective view of a fourth embodiment of a tank for use in a recirculation aquaculture system is shown at 40. The tank 40 also has a closed tubular shape such that an entrance of the tube is connected to an exit of the tube, and includes a tube wall. The tank 40 however, has the shape of an Irish knot that includes multiple loops 40 A, 40B, 40C that project out from a center of the tank 40, and then turn or fold back into the center of the tank to connect with a start point of an adjacent, next loop.

[0042]

[0030] Referring to Fig. 7, a perspective view of a fifth embodiment of a tank for use in a recirculation aquaculture system is shown at 50. The tank 50 also has a closed tubular shape and includes a tube wall 52. One or more openings or windows 54 are formed in the tube wall 52 and are configured to allow fish waste and / or shrimp waste to be washed, pushed, or otherwise removed from the tank 50. In the illustrated embodiment, one window 54 is shown formed in a lower, inside portion of the tube wall 52. An additional window 54, not visible in Fig. 7, is formed in a lower, inside portion of the tube wall 52 opposite, i.e., positioned 180 degrees from, the window 54 visible in Fig. 7. The opposing windows 54 are covered with a porous mesh or screen (not shown). The windows 54 are thus configured to allow water and fish waste and / or shrimp waste to exit, but keep fish and / or shrimp within the tank 50.

[0043]

[0031] Water inlet tubes 56, 58 penetrate, and are attached to, the tube wall 52 of the tank 50, such that they are fluidly connected to the tank 50. The tubes 56, 58 may include a porous mesh or screen (not shown) that covers the distal, open ends thereof. The mesh or screen is configured to allow water to flow into the tubes 56, 58, and therefore into the tank 50, but keep fish and / or shrimp within the tank 50. Alternatively, the mesh or screen may be mounted within the tubes 56, 58. The Attorney Docket No. 70419-WO-PCT

[0044] water inlet tubes 56, 58 are positioned and configured to create a circular flow of water through the tank 50.

[0045]

[0032] Additionally, the tube walls of any of the tanks 10, 20, 30, 40, 50 described herein may include perforations or openings (not shown) at predetermined locations. Such openings may be covered with a porous mesh or screen (not shown). Further, the openings may be formed at an oblique angle to a surface of the tube wall and are configured to contribute to, and accelerate the flow of water within each tank 10, 20, 30, 40, 50. The openings may be further configured to connect to a port to allow water to be pumped into the tank 10, 20, 30, 40, 50.

[0046]

[0033] Each of the tanks 10, 20, 30, 40 may also include one or more openings or windows, such as the window 54 shown in Fig. 7, formed in the tank or tube walls thereof, and that are configured to allow fish and / or shrimp waste to be washed, pushed, or otherwise removed from the tanks 10, 20, 30, 40, but keep fish and / or shrimp within the tanks 10, 20, 30, 40.

[0047]

[0034] In each of the tanks illustrated in Figs. 1 through 7, a set of internal structures are provided which help present fish with preferred flow features, and that implements a strong stream channel environment. As shown, such a channels define an endless path of various shapes, including, but not limited to, a simple circular torus, and a more complex infinite loop structure.

[0048]

[0035] Advantageously, each of the disclosed tanks ensures adequate water flow, so that operators can help prevent problems such as water quality issues, disease outbreaks, and reduced growth rates by supporting adequate levels of (1) waste removal - to route ammonia and nitrite to the biofilter; (2) oxygenation - efficiently distribute dissolved oxygen throughout the tank in high-density RAS systems where oxygen demand is high; (3) temperature control - distributing heat Attorney Docket No. 70419-WO-PCT

[0049] evenly throughout the culture tanks as fish are sensitive to temperature fluctuations; and (4) nutrient distribution - to help distribute feed throughout the tank. Because of these essential functional demands, RAS approximate more closely a flow through stream environment.

[0050]

[0036] Further, each of the disclosed tanks provides a set of specific current flow and stream profile features that are aligned with a particular fish species’ preferences. The tanks are designed to provide farm operator with enhanced predictability about the movement paths of individual fish.

[0051]

[0037] The principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.

Claims

Attorney Docket No. 70419-WO-PCTCLAIMSWhat is claimed is:

1. A fish handling structure for use in a recirculation aquaculture system comprising:a tank having a tank wall, wherein the tank has an interior water flow channel defining an infinite loop.

2. The fish handling structure according to claim 1, further including means for waste removal.

3. The fish handling structure according to Claim 1, wherein the flow of water in the water flow channel efficiently distributes dissolved oxygen throughout the tank.

4. The fish handling structure according to Claim 1, further including means to control water temperature.

5. The fish handling structure according to claim 1, further including means to distribute feed throughout the tank.

6. The fish handling structure according to claim 1, further including a fish sorter attached to the tank and fluidly connected to the interior water flow channel.

7. The fish handling structure according to claim 1, wherein the tank has an internal structure that creates an internal water flow channel that has the shape of a simple torus.Attorney Docket No. 70419-WO-PCT8. The fish handling structure according to claim 1, wherein the tank is a double water flow channel shaped tube.

9. The fish handling structure according to claim 1, wherein the tank has a closed tubular shape such that an entrance of the tube is connected to an exit of the tube, and the closed tube is folded onto itself.

10. The fish handling structure according to claim 1, wherein the tank has a closed tubular shape such that an entrance of the tube is connected to an exit of the tube, and wherein the closed tubular shape is further formed into the shape of an Irish knot.

11. The fish handling structure according to claim 1 :wherein the tank has a closed tubular shape such that an entrance of the tube is connected to an exit of the tube, includes a tube wall, and includes a plurality of windows formed in the tube wall that define a water outlet and are configured to allow aquatic animal waste to be removed from the tank;wherein the fish handling structure further includes a plurality of water inlet tubes fluidly connected to the tank;wherein each of the water inlet tubes include a porous mesh that covers the distal, open ends thereof; andwherein each of the windows is covered by a porous mesh.

Images