NO347766B1

NO347766B1 - Movable bulkhead for aquaculture system

Info

Publication number: NO347766B1
Application number: NO20221347A
Authority: NO
Inventors: Erlend Eide
Original assignee: Watermoon AS
Priority date: 2022-12-16
Filing date: 2022-12-16
Publication date: 2024-03-18
Also published as: NO20221347A1; NO347767B1; NO20230672A1; WO2024128924A1

Description

Movable bulkhead for a fish container

Field of the invention

The invention relates to movable bulkheads for closed submersible aquaculture systems and a method for operating said bulkhead.

Background

Extracting fish from fish containers may prove a difficult task. In closed submersible fish containers, the fish do not evacuate on their own motion simply by providing an opening for the fish to escape. Forcing fish out of a fish container directly with e.g. a vacuum hose or direct physical contact will damage the biomass and cause great stress amongst the fish affecting the fish quality.

Therefore, the fish should be nudged or encouraged out of the fish container allowing the fish, as much as possible, to evacuate on their own motion.

It is substantially harder to interact with and manage the biomass within closed submersible fish containers than open surface aquaculture systems.

Due to the mentioned issues, the current invention seeks to provide a solution for easily and gently extracting fish from closed submersible fish containers.

The following prior art may be relevant to the present invention.

WO2022158984A1 - Fish cage device comprising spherical fish cage:

This patent publication introduces a closed, spherical cage device designed for fish farming in floating positions in water. The cage is constructed with a pattern of polygons, divided along boundary lines consisting of tubular elements, forming a spherical skeleton. The tubular members contain inflatable buoyancy members with fluid communication to a reservoir of pressurized gas. A control unit regulates the gas amount, and the cage structure allows water inflow in areas not occupied by the buoyancy elements.

US20120132148A1 - Containment Pens for Finfish Aquaculture:

This patent publication describes a containment pen for finfish aquaculture, featuring a supporting structure with a net defining a containment volume. The net comprises removable panels, each attached to rigid members along its perimeter. Notably, these removable net panels are configured to be taken out of the containment pen while leaving the flexible netting attached to the rigid members.

NO20210119A - Submersible fish cage for sea-based farming:

This patent publication presents a submersible fish cage designed for sea-based farming of marine species. The cage includes a bottom unit, a center column, lower and upper arms, and at least one net wall defining a closed space for marine species. The upper arms are attached to a roof arranged for vertical adjustment, allowing flexibility in adjusting the volume defined by the net wall.

CN1747652A - Submersible netpen:

This patent publication relates to a netpen for fish breeding, storage, or transport in the sea, particularly in open sea regions. The netpen has a substantially spherical geometry and consists of a framework of stays made mainly of polyethylene or polyethylene-like materials. Notably, it features a buoyancyadjusting center pole, a liftable working platform with an integrated dock, and rotational capabilities.

US20140165922A1 - Center spar fish pen:

This fish pen disclosed in this patent publication includes an elongate spar buoy with optional reserve buoyancy, rim assemblies attached with tension members, and an adjustable upper connection plate for tensioning. The pen incorporates a docking station, portal for easy access, and a deployable panel system for managing fish within the pen.

NO20210232A - aquaocean Semi Submersible Fish Farm:

This patent publication introduces a floating structure for fish farming characterized by a polygonal or circular ring pontoon forming a basis for multiple columns/tanks containing fish. The tanks include water-perforable frame units and a net structure to control water flow. Interconnected tanks feature a closable lock structure, and each tank may have a perforated cofferdam collar to dampen water movement.

NO20170691A - Submersible breeding habitat with tie rod-anchored air space construction:

This patent publication describes a submersible breeding habitat for aquatic organisms comprising an air bell, an enclosure, and an anchoring system. The enclosure is vertically displaceable in relation to the air bell, providing flexibility in managing the breeding habitat.

FR2531835A1 - Chamber for rearing fish at sea:

This patent publication discloses a chamber for rearing fish consists of a framework defining the inner volume, surrounded by wire mesh or net. The framework has a revolution volume with two substantially conical opposite surfaces.

Summary of the invention

The invention relates to means for evacuating fish from a substantially closed and submerged fish reservoir.

List of figures

Fig. 1 is a cutaway perspective view of a fish container including a bulkhead of the invention in a collapsed state;

Fig. 2 is a cutaway perspective view of a fish container including a bulkhead of the invention in an expanded state;

Fig. 3 is a cutaway perspective view of a fish container including a bulkhead of the invention in a lowered position; and

Fig. 4 is a cutaway perspective view of a fish container including a bulkhead of the invention in a lowered position.

Detailed description of embodiments

In this application, the term aquaculture system is intended as a general expression comprising a fish pen, a fish tank, a fish cage, an aquaculture facility and equivalents. An aquaculture system comprises a container (e.g. a fish container) providing a reservoir for aquatic organisms. The term “fish container” is used as a general expression for containers suitable for containing fish, however, the fish container referred to in this application may contain any aquatic organism, and what applies for fish in this application may also apply for other similar aquatic organisms.

The fish container may be permeable or non-permeable, flexible or rigid. The internal volume of the fish container housing a biomass such as fish may be referred to as a biomass reservoir volume which is distinguished from other internal volumes of the fish container which does not contain or is not intended for containing aquatic organisms.

Fig. 1 is a cutaway perspective view of a fish container 10 including a bulkhead 100 of the invention in a collapsed state. The fish container 10 has an exterior enclosure 101. A part of the exterior enclosure 101 is cut out to view the inside of the fish container 10. In the collapsed state the bulkhead surface 110 has a substantially elongated and tubular shape with a diameter smaller than a diameter of an opening into the fish container 10. The collapsibility which makes it easy to insert into and extract through narrow openings/hatches etc. In the collapsed state the bulkhead surface 110 forms a shape similar to a folded umbrella or a folded and cylindrical skirt.

The fish container 10 includes a bottom portion 103 and may include a top portion 104. The bottom portion 103 may be tapered towards the bottom end.

The fish container 10 may be of any shape. Seen from above (not shown) the fish container 10 may have a circular, conical, rectangular or square horizontal crosssection. It may have a tapered, conical, convex or concave bottom portion or a flat bottom portion.

The exterior enclosure 101 may be rigid or flexible. The fish container 10 may be permeable or non-permeable.

In the embodiment of Fig.1, the fish container 10 has a substantially cylindrical middle portion with a tapered top portion 104 and a tapered bottom portion 103, although this figure only serves as one example of many fish container shapes.

The fish container 10 may have a closed top portion 104 and a closed bottom portion 103 providing a complete enclosure for the fish. The fish container 10 may therefore be completely submerged.

The fish container 10 may include a top support section 105 preferably of a rigid material.

The fish container 10 may include an opening 172 in its top portion to provide access to the internal volume of the fish container.

The opening 172 may include a hatch (not shown). Preferably the opening 172 is integrated in the top support section 105. The hatch may be opened or closed to provide access to the internal volume of the fish container 10 and to close the fish container 10. The hatch may therefore provide an opening 172 in the top portion 104.

Fig. 1 further shows a bulkhead 100 according to the invention positioned inside the fish container 10. The bulkhead 100 includes a bulkhead surface 110. The bulkhead surface 110 may be of any permeable or non-permeable structure/material such as polymer, composite, metal or fabric. The bulkhead surface 110 may be both flexible and rigid. The bulkhead surface 110 may have a perforated structure such as a net or a mesh. The bulkhead 100 further includes a continuous expansion tube 120 which is fastened along a circumference 140 (see Fig. 2) of the bulkhead 100.

The bulkhead 100 is expandable and collapsible. In Fig.1 the bulkhead 100 is in a collapsed state.

The bulkhead 100 may be lowered down through the opening 172 preferably when the bulkhead 100 is in its collapsed state. The bulkhead 100 may be lowered with moving means 171. The moving means 171 may include at least one wire, chain, rope, cable or line of any material. The moving means 171 may be connected to a winch. The moving means 171 may also be a rigid element such as a steel rod which can be moved actively by a motor in and out of the fish container 10.

The bulkhead 100 may be lowered actively with a winch or motor, or passively means of gravity. The bulkhead 100 may be provided with weight elements to achieve a desired weight. The bulkhead 100 may be moved up/down or sideways inside the fish container 10 actively by means of a motor or winch, by manual labour or by gravity. For sideways movement the bulkhead 100 is preferably inserted through an opening located in a side of the fish container 10 (not shown).

In general, the bulkhead 100 is intended to move in a direction against an internal biomass in the fish container 10 in order to decrease the biomass reservoir volume, encouraging the biomass to evacuate the fish container 10 though an outlet.

The bulkhead 100 can also be inserted from a side opening (not shown) in the fish container 10 or a bottom opening (not shown) in the fish container 10.

Once the bulkhead 100 is lowered into the internal fish reservoir i.e. the internal volume of the fish container 10, the fish will according to its biological instincts move downwards and at least away from the introduced bulkhead 100.

A fish outlet 700 may be located in the bottom portion 103 of the fish container 10. A fish outlet 701 may also be located in a top portion 104 of the fish container 10.

Fig. 2 is a cutaway perspective view of a fish container 10 including a bulkhead 100 of the invention in an expanded state.

After the bulkhead 100 (in its collapsed state) has been lowered at least partly into the fish container 10, the bulkhead 100 may be expanded into its expanded state to cover the largest horizontal cross-section of the fish container 10.

The expansion tube 120 is fastened along the circumference 140 of the bulkhead surface 110. In the embodiment of Fig.2 the bulkhead surface 110, and consequently also the expansion tube 120, is circular in the expanded state. The bulkhead surface 110 and the expansion tube 120 may however be of any shape corresponding to the inner surface of the fish container 10. In the expanded state, the expansion tube 120 is configured to abut against the inner surface of the fish container 10 along the length and outer surface of the expansion tube 120 creating an impenetrable barrier for aquatic organisms within the fish container 10.

The bulkhead 100 may be lowered from a topside location.

The moving means 171 is preferably connected to a central portion of the bulkhead 100.

In an aspect, the fish container 10 may include a centre column 800. In this aspect the bulkhead 100 includes a centred opening 130 through which the centre column 800 may extend. The centred opening 130 is preferably provided with a support collar 131 which is fastened along the perimeter of the centred opening 130. The support collar 131 may be torus shaped. The support collar 121 is preferably of a rigid material. The moving means 171 is preferably connected to the support collar 131.

In another aspect the fish container 10 may also not include any centre column 800. In this aspect, the bulkhead 100 may not include a centred opening 130 so that the bulkhead surface 110 forms a continuous surface without any centred opening. The moving means 171 may in this aspect be fastened to a central part of the bulkhead surface 110 by means of any conventional fastening means, the central part being preferably reinforced.

The expansion tube 120 extends along the bulkhead circumference 140. The expansion tube 120 is a hollow tube of a fluid tight material. The expansion tube 120 is equivalent with a fluid channel or a fluid conduit. The expansion tube 120 is preferably of a flexible material comprising a polymer, composite or fabric material.

A fluid control means 160 is provided in fluid connection with the expansion tube 120. The fluid control means 160 may be a hydraulic or pneumatic pump configured to inject or withdraw fluid to/from the expansion tube 120 and to provide constant hydrodynamic or pneumatic pressure to the expansion tube 120. By injecting a fluid the expansion tube 120 will gradually form a rigid support structure and expand the bulkhead surface 110 along a horizontal or vertical plane.

When the expansion tube 120 is pressurized the expansion tube 120 will expand, also causing the bulkhead surface 110 to expand. The bulkhead surface 110 is preferably sized to create a barrier across the largest horizontal or vertical crosssection of the fish container 10. The expansion tube 120 preferably abuts the inner surface of the fish container 10 along its entire length.

The expansion tube 120 may be injected with a fluid such as sea water, air or any other fluid. The expansion tube 120 is preferably filled with sea water.

The fluid control means 160 may be located within the fish container 10 or outside the fish container 10 in direct or indirect connection with the expansion tube.

Preferably the fluid control means 160 is located top side. The fluid control means 160 may be connected to the expansion tube 120 via at least one fluid transport means being a cable or a tube or a hose etc. (not shown). The fluid transport means may run through the opening 172 along within the moving means 171. The fluid control means 160 may also be a compact impeller, propeller, gas canister or other conventional means for providing hydrodynamic or pneumatic pressure to expand the expansion tube 120.

The fluid control means 160 may be actuated to operate in reverse, withdrawing fluid from the expansion tube 120 causing the expansion tube 120 to collapse. The fluid control means 160 may also have a pressure release valve for releasing pressure, also causing the expansion tube 120 to collapse.

After the bulkhead 100 has been lowered into the internal fish reservoir, the fish has already fled downwards or away from the bulkhead 100 and is therefore already located below the bottom end of the bulkhead surface 110, or on the side of the bulkhead surface 110 opposite of the opening 172, due to biological instincts. Therefore, when the bulkhead 100 is expanded, the fish is located below, or on the side of the bulkhead surface 110 opposite of the opening 172 of, the expanded bulkhead surface 110.

After the bulkhead 100 has been expanded it is lowered further down inside the fish container 10 causing the fish to flee further down to a fish outlet 700 located in the bottom portion 103 of the fish container 10 where they eventually will evacuate through the fish outlet 700. A fish evacuation amount is dependent on how much the fish reservoir volume has been decreased by the bulkhead 100, in addition to general disturbance of the internal water.

The fish outlet 700 may be a fish evacuation port/opening/gate/hatch located in the bottom portion 103. The fish outlet 700 may be connected to a fish transport means 690 (see Fig.3 and 4) such as a fish transport hose or tube or any other conduit – pressurized or non-pressurized.

The fish outlet 700 may be connected to the centre column 800 and the centre column 800 may comprise a fish transport means 690 extending through the centre column 800 to a top fish outlet 701 (see Fig.3), which allows fish to travel up through the centre column 800 and out of a top fish outlet 701 located in a top portion of the fish container 10.

The fish (not shown) evacuates through the fish outlet 700. In an aspect the fish transport means 690 may extend between the fish outlet 700 and the top fish outlet 701.

The fish transport means 690 may be hydrodynamically pressurized to yield a current for transporting fish and other aquatic organisms, operating essentially as a vacuum hose.

The fish outlet 700 may also directly or indirectly be connected to an auxiliary fish pen, tank or cage. The fish outlet 700 may also be connected indirectly to a service vessel for transporting or treating fish. The fish outlet 700 may be connected to a centre column 800 inside which the fish may travel through the centre column 800 and out of the fish container 10.

Fig. 3 is a cutaway perspective view of a fish container 10 including a bulkhead 100 of the invention in a lowered position.

In Fig.3 the bulkhead 100, in its expanded state, has been lowered to a level where the expansion tube 120 rests against the inner surface of the fish container 10. In Fig.3 the fish container 10 has a tapered lower portion 190 reducing the horizontal cross-sectional area of the fish container 10. Consequently, the expansion tube 120 is held back from being lowered any further. Since the moving means 171 are preferably connected to a central part of the bulkhead surface 110, when lowering the bulkhead 100, the bulkhead surface 110 area will increasingly rest against and cover the inner surface of the tapered lower portion 190 decreasing the biomass reservoir volume completely or nearly completely.

The bulkhead 100 of the invention may also be used for flat bottomed fish containers, wherein the bulkhead surface 110 can be positioned to rest against the flat bottom, decreasing the biomass reservoir volume completely or nearly completely.

The bulkhead 100 may be provided with least one hollow radial tube 180 connected to the bulkhead surface 110. The radial tubes 180 are preferably made of a flexible material. The radial tubes 180 preferably extends between the expansion tube 120 and the support collar 131.

Fig. 4 is a cutaway perspective view of a fish container 10 including a bulkhead 100 of the invention in a lowered position. In Fig.4 the bulkhead 100 has been lowered even further than in Fig.3. The support collar 131 is now located below the expansion tube 120 causing each radial tube 180 to slope downwards, presuming the bottom portion of the fish container 10 is tapered downwards.

Each radial tube 180 may be configured to contain a weight 181. The weights 181 may be fixed to a specific position along the radial tube 180, or the weights 181 may be free to slide/move inside the radial tube 180. The latter case is shown in Fig. 4. Since each radial tube 180 slopes downwards, the weight 181 will slide downwards providing a gravitational force to the bulkhead surface 110. As the bulkhead 100 is lowered further, the weights 181 moves inward to a central part of the bulkhead surface 110, forcing the whole of the bulkhead surface 110 against the bottom portion 103.

When the bulkhead 100 is lowered sufficiently, the bulkhead 100 may decrease the entire volume or nearly the entire volume below the bulkhead 100. This provides the ability to completely evacuate the internal biomass from the fish container 10 even for fish containers having a tapered bottom portion 190.

The fish (not shown) evacuates through the fish outlet 700. In an aspect the fish transport means 690 (see Fig.3) may extend between the fish outlet 700 and the top fish outlet 701. In this case, the fish follow direction 750. On another aspect shown in Fig.4 the fish outlet 700 may guide the fish out through a fish transport means 690 running outside the fish container 10 following a direction 751.

In an aspect the bulkhead 100, (see Fig.1-4) may be lowered into the fish container 10, expanded and completely lowered against the bottom portion 103, before fish enters the fish container 10. When the fish is ready for evacuation, the bulkhead 100 may be pulled upwards forcing or encouraging the fish upwards through a top opening 701. The top opening 701 may be connected to a top side fish pen or any other container or enclosure possibly via a fish transport means such as a hose, tube, or any other conduit.

Claims

PATENT CLAIMS

1. Moveable bulkhead (100) for a closed submersible aquaculture system comprising a fish container (10), comprising:

● a bulkhead surface (110) comprising a bulkhead surface circumference (140);

● an expansion tube (120) fixed to and extending along the bulkhead surface circumference (140) for expanding and collapsing the bulkhead (100) between a collapsed state and an expanded state; ● wherein the expansion tube (120) is in fluid connection with a fluid control means (160) for injecting and withdrawing fluid to and from the expansion tube (120);

● moving means (171) connected to the bulkhead (100) for moving the bulkhead (100) inside the fish container (10).

2. Moveable bulkhead (100) according to claim 1,

● wherein the bulkhead (100) is configured to move vertically within the fish container (10).

3. Moveable bulkhead (100) according to any preceding claims, wherein the bulkhead surface (110) comprises a centred opening (130).

4. Moveable bulkhead (100) according to claim 3,

● wherein a support collar (131) is fixed to the centred opening (130);

and

● wherein the moving means (171) comprises at least one wire, cable or line connected to the support collar (131).

5. Moveable bulkhead (100) according to any preceding claims, wherein when the bulkhead (100) is in its expanded state, the expansion tube (120) is configured to abut against the inner surface of the fish container (10) along the length of the expansion tube (120) creating a barrier for aquatic organisms within the fish container (10).

6. Moveable bulkhead (100) according to any preceding claims, comprising at least one radial tube (180) for containing or holding a weight (181), the radial tube (180) extending between a centre of the bulkhead surface (110) and the bulkhead surface circumference (140).

7. Moveable bulkhead (100) according to claim 6, wherein the weight (181) is free to move within the radial tube (180).

8. Moveable bulkhead (100) according to claim 4 and any of the preceding claims 5-7, wherein the at least one radial tube (180) extends between the support collar (131) and the expansion tube (120).

9. Moveable bulkhead (100) according to any preceding claims, wherein the bulkhead surface (110) is permeable.

10. Moveable bulkhead (100) according to any preceding claims 1-8, wherein the bulkhead surface (110) is non-permeable.

11. Moveable bulkhead (100) according to any preceding claims, wherein the expansion tube (120) and/or the at least one radial tube (180) is made of a flexible material comprising a polymer, a composite or a fabric material.

12. Method of operating a moveable bulkhead (100) according to any of the preceding claims within a closed submersible fish container (10), comprising the steps of:

● providing an opening (172) in the fish container (10);

● moving the bulkhead (100) through the opening (172) while the bulkhead (100) is in its collapsed state by means of the moving means (171);

● injecting fluid into the expansion tube (120) using the fluid control means (160) until the bulkhead (100) reaches its expanded state. ● moving the bulkhead (100) in a direction which decreases a biomass reservoir volume.

13. Method according to claim 12 of operating a moveable bulkhead (100) according to claim 7 and optionally any of the preceding claims 8-11 when dependent on claim 7, further comprising the steps of:

● lowering the bulkhead (100) in its expanded state until the expansion tube (120) reaches a tapered bottom portion (190) or a bottom portion (103) of the fish container (10) preventing the expansion tube (120) from being lowered further;

● further lowering the bulkhead (100) until the at least one radial tube (180) slopes downwards allowing the weight (181) to slide downwards pressing the bulkhead surface (110) against the inner surface of the fish container (10), or further lowering the bulkhead (100) until the bulkhead surface (110) rests against substantially the entire bottom portion (103) of the fish container (10).

14. Method according to any of claims 12 or 13 further comprising the steps of:

● withdrawing fluid from the expansion tube (120) or decreasing the fluid pressure within the expansion tube (120) using the fluid control means (160) until the bulkhead (100) reaches its collapsed state. ● moving the bulkhead (100) out through the opening (172).

P ATENT C LAIMS