NO342583B1 - Aquaculture plant with aquaculture and waste container - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a fish farm (1) for farming live fish (F), comprising a fish farm (10) and a container device (20). The farming cage (10) comprises a first float device (11) and a bag (12) attached to the float device (11), wherein the bag (12) is provided for storing fish (F); The container device (20) comprises second flow device (21) and a container (22), the container (22) being provided for storage of waste (FF). Furthermore, a waste transport system (40) is provided for transporting waste from the first bag (12) of the farming cage (10) to the container (22) of the container device (20).

Description

FIELD OF THE INVENTION

The present invention relates to a breeding facility for breeding live fish.

PRIOR ART

A number of different types of breeding facilities are known for use in the sea consisting of a number of breeding cages. A first type of rearing facility comprises rearing cages with a first floating and expansion device, where a rearing bag is suspended below the first floating and expansion device. The flotation and expansion device often comprises a floating ring made of plastic, alternatively it can be made as an expansion device in the form of a metal structure that has buoyancy or is attached to flotation elements. The metal structure can often be square or rectangular, so that several such floating devices, each with their own rearing bags, can be mounted close to each other. The floating and expansion device will typically be located at or near the surface of the sea. In addition, the rearing cages in the rearing facility may include one or more additional expansion devices at a desired depth. In this first type of breeding facility, the breeding bag is made of a mesh material, i.e. a material with openings that allow water to flow through the material and which at the same time keeps the fish trapped on the inside of the breeding bag. Supply of fresh water is caused here by natural currents in the sea where the farm is located.

The first type of breeding facility has several disadvantages. Feed residues and faeces (faeces from fish) fall as sludge on the seabed below the farm and cause local pollution if the farm is not in a location with ocean currents and great water depth that bring feed residues and faeces with them. This means that there are limited sea areas that are available for aquaculture facilities, with subsequent limits on the amount of fish that can be farmed in an area. Furthermore, it is a big problem that the fish in the rearing bag get salmon lice or other parasites or diseases that come with the water bodies. Optimal growth of the fish depends on optimal water temperature. This is difficult to control when it is only the sea that flows through the plant that determines the temperature.

Another type of farm is often called a semi-closed farm. Clean water is pumped into these plants, often from deep water without salmon lice.

Forrester and faeces are dumped at the bottom of the facility and area restrictions due to pollution under the cages also apply here.

The construction of a third type of aquaculture facility may be quite similar to the second type, but in the third type of aquaculture facility, the water coming out of the facility is purified. The water to be cleaned has very large volumes, in the order of 0.4 liters per kg of fish per minute (600 liters per kg. fish per day). If these volumes are to be sent to a treatment plant on land, it entails large energy costs to lift the water up even a few metres. The cleaning process itself on land will also be extensive and expensive.

EP 215755 A1 describes a breeding facility where the tanks for storing fish are made of a flexible material. These thoughts are closed. Waste is fed from the bottom of the tank to a collection tank. The collection tank can be shared by several breeding tanks and is closed so that no pollution will escape to the surroundings. Waste can be fed from the rearing tanks to the tank by temporarily increasing the pressure in the tank compared to the pressure in the tank. It is described that the system is closed and that no pollution will escape to the surroundings.

WO 97/38573 describes a breeding system consisting of tanks 1 with rigid walls. Waste is led from the bottom of the tanks via a pipeline to a so-called "collection and settling tank". From here, the waste is released to the water outside the tanks or the waste can pass through a treatment plant before being released into the water outside the plant. All tanks are described as having sufficient structural rigidity to withstand forces from currents in the water.

NO 339302 B1 describes a waste collection system with a pump system with a suction head, a line, an air injection device and an air device. The focus here is how waste is moved from a cage in a breeding facility. The waste reception station is described to preferably be located above sea level, for example on a raft. The waste reception station can also be located on land.

NO 176741 B describes a breeding facility where waste is collected in two different places, a collection container and a sludge separation container. Some waste is retained in the sludge separation container, while the rest is led to the collection container through a line. The sludge separation container has a large volume so that the sludge settles without being disturbed by the inflowing mixture of sludge and water. The collection container is made of metal or plastic and can be tilted around (fig. 3) when it is to be emptied into a container on board the vessel. The collection container is moved from dam to dam when these are to be emptied, which requires a separate vessel.

NO 333633 B1 describes a breeding facility consisting of two main parts,

a) a floating cage or a group of cages that have their own mooring and anchoring systems, and

b) a "central" fleet of up to several hundred tonnes of deadweight which accommodates silos, (...), waste management and a number of other functions. The central raft floats high in the water. The two main parts behave differently in the sea due to their different construction, intermediate rafts help to reduce the problems with this. Here, the collection point for waste is therefore part of the central fleet. This is described as a rigid structure that behaves differently in the sea than the breeding cages.

It is an aim of the present invention to provide a breeding facility which helps to significantly reduce local pollution from feed residues and faeces and which reduces or prevents salmon lice from establishing themselves in or escaping from the breeding facility. Thus, the breeding facility will be able to be used in locations where it is not currently advisable to have breeding facilities. Furthermore, it is a purpose that the breeding facility nevertheless has a relatively simple construction and has relatively low investment and operating costs. Furthermore, the invention will enable the reuse of sludge from faeces and feed residues which can have value as, for example, fertiliser.

SUMMARY OF THE INVENTION

The present invention is defined in the independent claim 1. Aspects of the invention appear from the non-independent claims.

More specifically, the present invention relates to a breeding facility for breeding live fish, comprising:

- a rearing cage comprising a first flotation device and a bag attached to the flotation device, the bag being provided for the storage of fish;

- a container device comprising a second floating device and a container, where the container is provided for storing waste;

- a waste transport system for transporting waste from the first bag at the rearing pen to the container at the container device;

wherein the container is a second bag attached to the second floatation device; characterized by that

- the second bag is made of a flexible, dense canvas material;

- the container has a maximum filling level for waste at a depth;

- the container comprises openings at a depth higher than the maximum filling level; - the waste transport system is configured to control the water level in the container to be higher than the water level in the water outside the breeding facility.

In one aspect, the water level in the container is 0.5 - 300 mm, preferably 1 - 50 mm higher than the water level in the water outside the breeding facility.

In one aspect, the waste transport system comprises pipes connecting a lower region of the first bag at the rearing pen to the container at the container device; where the waste transport system further comprises a pumping device for pumping waste from the bag to the container.

In one aspect, at least one of the flotation devices is provided by a flexible material.

In one aspect, at least one of the flotation devices is inflatable.

In one aspect, at least one of the floating rings is provided by a rigid material, or that a floating ring is provided on the outside of the floating rings.

In one aspect, the farm comprises:

- a plurality of rearing cages, each with its first flotation devices and bags;

- one common container device with a container;

where the waste transport system is configured to transport waste from the first bag at the plurality of rearing cages to the container at the common container device.

In one aspect, the rearing cage is provided separately from, and at a distance from, the containment device.

DETAILED DESCRIPTION

Embodiments of the present invention will be described in detail below with reference to the attached figures, where:

Fig. 1 shows a schematic side view of a first embodiment of the breeding facility; Fig. 2 shows a schematic cross-section of a first embodiment of the container device;

Fig. 3 shows a schematic cross-section of a second embodiment of the container device;

Fig. 4 illustrates an alternative embodiment of fig. 1;

Fig. 5 illustrates a perspective view from above of a third embodiment;

Fig. 6 illustrates a perspective view from above of a fourth embodiment.

In the description below, the term "waste" is used for feed residues, faeces and other types of waste in the form of solid particles that are present in a breeding facility. Waste is referred to with reference number FF. Waste consists of a number of substances, where most of the phosphate will be bound to solid particles. Nitrogen, another substance in the waste, will be approximately two-thirds dissolved in water and one-third bound to solid particles. Some of the solid particles of the waste will sink quickly to the bottom, other solid particles will sink more slowly to the bottom.

Reference is first made to fig. 1. Shown here is a breeding facility 1 for breeding live fish marked with the letter F. The breeding facility 1 here comprises three breeding cages 10. Each breeding cage has a first floatation device 11 and a bag 12 attached to the floatation device 11, where the bag 12 is provided for storage of fish F. Waste FF will sink in the rearing cages 10 towards the bottom of the bag 12.

In addition, the breeding facility 1 comprises a floating container device 20 for receiving and storing waste FF from the breeding cages 10. The container device 20 comprises a second floating device 21 and a container, generally referred to by reference number 22, in which the waste is stored. In the present embodiment, the container 22 a second bag 22 made of a flexible, dense material, such as a dense cloth material. The cloth material can, for example, be fibre-reinforced, coated cloth. It may be mentioned that in alternative embodiments the container 22 is made of a rigid, dense material, such as PE plastic or steel or other suitable materials. Furthermore, the breeding facility 1 comprises a waste transport system 40 for transporting waste FF from the first bag 12 at each breeding cage 10 to the bag 22 at the container device 20. In fig. 1, the waste transport system 40 comprises pipelines 41 from the bottom of the respective bags 12 to a pump device 44 which provides for pumping water with waste from the bags 12 into the bag 22 of the container device 20 via a pipeline 42. The pipeline 42 is here led in through the bottom of the bag 22 and protrudes a little way up into the bag 22. It should be emphasized that although the pump device 44 is shown here positioned submerged in the sea, this is only intended as a schematic drawing. For many reasons (maintenance, repairs etc.) it is most practical to place the pump device 44 above the sea surface. Examples of this will be described below.

The breeding facility 1 is a breeding facility for breeding live fish F in water, typically in the sea or ocean. The breeding cage 10 can be of a type mentioned at the outset where the supply of fresh water is caused by natural currents in the sea where the breeding facility 1 is located. However, a good deal of waste FF will in this case be carried out of the bag 12 by the same natural currents. In order to avoid or reduce this, the rearing pen 10 in the present invention preferably has a bag 12 which is so dense that a controlled supply of water from the outside is required. Accordingly, the bag 12 of the rearing cage 10 is also preferably made of a flexible or rigid, dense material, such as a dense canvas material of the type mentioned above. How fresh water is supplied may depend on how the waste transport system 40 is designed, and will be discussed in detail further down.

The flotation devices 11, 21 primarily have the function of providing buoyancy, but can also have the function of providing expansion of the bags 12, 22.

The flotation devices can thus be of the known type as mentioned at the outset, i.e. as relatively rigid plastic rings filled with air or a material with positive buoyancy, alternatively made as an expansion device in the form of a metal structure which is again attached to or has built-in flotation elements. In a preferred embodiment, the floating devices 11, 21 are made of a flexible plastic material filled with air connected to relatively tight bags 12, 22 and where the flexible plastic material is stretched out by the water level inside that bag 12, 22 being higher than the water level in the sea. In this case, the flotation device is therefore inflatable. In this case, the breeding facility 1 will include further expansion devices or anchoring devices to ensure sufficient rigidity so that the cages 10 and the container device 20 can withstand being anchored to the seabed or to land. This will be described in detail further down.

Preferably, the rearing cage 10 is provided separately from, and at a distance from, the container device 20. Such a distance is indicated in fig. 1 with dashed line d.

Reference is now made to fig. 2, which shows the container device 20 with float device 21 and bag 22. It is shown here that the pipeline 42 protrudes through the bottom of the bag 22 and up to a height H42 in the bag 22. Water containing waste FF will enter the bag 22 where the waste FF will sink towards the bottom of the bag 22. It is in fig.

2 also shown that the bag 22 has a maximum filling level for waste FF at a depth Hmax. This maximum filling level can be determined by a number of factors, such as available buoyancy in 21 in relation to the weight in water of the waste FF or purely logistical conditions such as how often the container device 20 can be emptied of waste FF and what capacity reserve is required. It may also be noted that the conduit 42 may pass through the wall of the container 22 at any level between the bottom and the surface H22.

It is in fig. 2 also shown that the bag 22 comprises openings 23 in the otherwise dense cloth material. The openings 23 are preferably provided at a depth H23 higher than the maximum filling level Hmax. Water-dissolved nitrogen and other, lighter types of waste will therefore be able to be released from the bag. This waste will then be transported by currents in the sea away from the farm. The openings 23 can be openings 23a in the dense cloth material and can be distributed around the periphery of the bag 22, alternatively the openings 23 can be provided as one or more pipes 23b through the bag 22. The pipe or pipes 23b can further be connected to a pipe system (not shown ) which transports the relatively particle-free waste water away from the breeding facility 1 for further cleaning, filtering of lice and lice larvae, or for discharge into the surroundings at a more optimal location.

In fig. 2 it is also shown that the water level H22 in the container 22 is higher than the water level H0 in the water V outside the breeding facility 1. With this, the above-mentioned expansion of the float device 21 is achieved in the cases where the float device 21 is made of a flexible material. Furthermore, it is achieved that water with water-dissolved waste is pushed out of the openings 23.

It will be the waste transport system 40 that ensures this higher water level H22, in that the waste transport system is configured to control the pump device 44 to pump a predetermined amount of liquid (water and waste FF from the cages 10) to the bag 22 per unit of time. This predetermined amount of liquid will be determined, among other things, by the total volume of the bag 22 and the size of and/or the number of openings 23. Alternatively, the waste transport system 40 can be configured to control the pump device 44 by means of sensors, for example sensors that measure the height H22 in relative to the height H0, alternatively a flow meter that measures the water flow out through the openings 23. Such a flow meter can preferably be placed in an opening 23 in the form of a pipe 23b.

The water level H22 in the container 22 can be from 0.5 - 300 mm, but is preferably 1 - 50 mm higher than the water level H0 in the water V outside the breeding facility 1.

In order for the waste FF to have enough residence time in the container 20 so that the waste FF can sink down or settle to the bottom of the container 20, it would be an advantage if the container 20 has a large volume in relation to the supplied amount of effluent water.

Reference is now made to fig. 3, which shows an alternative embodiment of the container device 20 in fig. 2. This container device has many similarities with the container device in fig. 2, these similarities will not be described here. One of the differences with the container device 20 in fig. 3 is that the pipeline 42 is not brought through the lower area of the bag 22, instead the pipeline 42 is provided in an upper, central area of the bag 22. Here too, waste FF in the form of particles will sink into the bag 22, while water containing water-dissolved waste substances will be emptied out through openings 23. Here, too, the pipeline can pass through the container wall 22, for example right at or just below level H22.

Reference is now made to fig. 4, which shows an alternative embodiment of fig. 1. Again, only differences between fig. 4 and fig. 1 will be described here. While the waste transport system 40 in fig. 1 had a common pump device 44, then the waste transport system 40 in fig. 4 three pump devices 44, one for each cage 10. If waste FF is not continuously emptied from the bags 12, the water quality will be so reduced that fish must be transferred to another location (well boat, other cage, possibly sent for slaughter). This applies in particular if the cage 10 is of a type where there are no natural currents that ensure the supply of fresh water.

The pumping devices 44 are shown submerged in the sea and mounted under the bags 12.

A long-term fault in the pump device 44 will in fig. 1 result in reduced water quality in all three cages 10, while a long-term fault in one of the pump devices 44 in fig. 4 will result in reduced water quality only in the relevant cage 10.

Reference is now made to fig. 5. Shown here is a breeding facility 1 with six breeding cages 10 and a common container device 20. Here, too, each breeding cage 10 comprises a floating device 11 and a bag 12 for storing fish, and the container device 20 comprises a floating device 21 and a bag 22. The bags 12, 22 are here made of a dense cloth material.

Each floating device 11, 21 is here attached to an anchoring device in the form of an anchoring ring 13, 23 provided on the outside of the floating devices. In fig. 5, each floating device 11 and its associated anchoring ring 13 are drawn together as a thicker solid line. In the same way, the floating device 21 and its associated anchoring ring 23 are also drawn together as a thicker solid line.

The anchoring rings 13, 23 are anchored to the seabed by means of anchoring buoys 51, anchoring lines 52 and anchors 53. The anchoring rings 13, 23, as well as an anchoring system 50 with anchoring buoys 51, anchoring lines 52 and anchors 53 are considered known to the person skilled in the art and will not be described in more detail here.

Each breeding pen here also includes a water supply system 60 for supplying fresh water and, if available, lice-free water to each pen.

The water supply system 60 comprises a pumping device 64 for pumping water from an area outside the bags 12 and into the bags 12.

In fig. 5 it is also shown that the waste transport system 40 comprises a raft 46 on which the pump device 44 is placed. Pipelines 41 lead waste from the bottom of the bags 12 to the pump device 44 and a pipeline 42 leads the waste further to the bag 22.

The pump devices 44 and 64 can be controlled individually, for example based on sensors that register the relative height of the water level in each bag. Alternatively, they can have a common management system.

Reference is now made to fig. 6. Here, a breeding facility is shown with eight breeding pens 10 and one common container device 20. Here, the waste transport system 40 comprises a pipeline 41 from the bottom of the bag 12 at each breeding pen 10 and up to a raft 46 attached to a floating device 11, alternatively to an anchoring ring 13, where a pump device 44 is placed on the raft 46. A pipeline 42 is led from the pump device 44 to the container device 20.

The pump device 44 here also pumps waste FF from the bottom of the bag 12 via the pipelines 41, 42 to the container device 20. It should be noted here that, like the embodiment in fig. 6 here is one pump device per breeding pen 10, so that if a fault occurs in one of the pump devices 44, this will possibly only have consequences for the water quality in the relevant breeding pen 10. It should also be noted that the pump devices 44 here are placed above the water surface for easy accessibility for maintenance/repair.

This embodiment in fig.6 can have floatation devices 11, 21 which both ensure buoyancy and expansion of respective bags 12, 22, or can alternatively have floatation devices 11, 21 which only provide buoyancy and then additionally have anchoring rings 13, 23. fig. 6 it is shown that the floating devices 11, 21, alternatively the anchoring rings 13, 23, are anchored to the seabed by means of anchoring buoys 51, anchoring lines 52 and anchors 53 as in fig. 5.

It is also shown that each breeding pen 10 in Fig. 6 has a water supply system 60, as described above.

In the above embodiments, the waste container 20 will be emptied as needed, for example by means of a vessel with suitable pumping and transport capacity.

In the above embodiments, there is one common container device 20 with a container 22 for all the breeding pens 10. It will of course be possible to have a breeding facility 1 with a single breeding pen 10 and a single container device 20.

In a particular embodiment, the waste transport system 40 will only consist of a pipeline 41 out of the bag 12 and a pipeline into the bag 22, i.e. that the waste transport system 40 is without a pump device 44. In such an embodiment, the liquid flow from the cage 10 to the container device 20 will be caused by the water supply of fresh water into the cage 10 which leads to an overpressure in the cage 10 which in turn causes a liquid flow from the bag 12 to the bag 22. It should be noted that the relative position internally in the breeding facility 1 between the breeding cage 10 and the container device 20 can of course vary depending on which is, for example, most optimal with regard to carrying away surplus water using natural water flow so that fresh water to be pumped into the rearing cages 10 is not contaminated.

Claims (8)

PATENT CLAIMS 1. Farming facility (1) for breeding live fish (F), comprising: - a rearing cage (10) comprising a first flotation device (11) and a bag (12) attached to the flotation device (11), where the bag (12) is provided for the storage of fish (F); - a container device (20) comprising a second float device (21) and a container (22), where the container (22) is provided for storing waste (FF); - a waste transport system (40) for transporting waste from the first bag (12) at the rearing pen (10) to the container (22) at the container device (20); where the container (22) is a second bag (22) attached to the second float device (21); characterized by that - the second bag (22) is made of a flexible, dense cloth material; - the container (22) has a maximum filling level for waste (FF) at a depth (Hmax); - the container (22) comprises openings (23) at a depth (H23) higher than the maximum filling level (Hmax); - the waste transport system (40) is configured to control the water level (H22) in the container (22) to be higher than the water level (H0) in the water (V) outside the breeding facility (1). 2. Breeding facility in accordance with claim 1 where the water level (H22) in the container (22) is 0.5 – 300 mm, preferably 1 – 50 mm higher than the water level (H0) in the water (V) outside the breeding facility (1). 3. Breeding facility in accordance with one of the above claims, where the waste transport system (40) comprises pipes (41) which connect a lower area of the first bag (12) of the rearing pen (10) to the container (22) of the container device (20); where the waste transport system (40) further comprises a pumping device (44) for pumping waste (FF) from the bag (12) to the container (22). 4. Farming facility in accordance with one of the above requirements, where at least one of the floating devices (11, 21) is provided from a flexible material. 5. Farming facility in accordance with claim 4, where at least one of the floating devices (11, 21) is inflatable. 6. Farming facility in accordance with one of the above requirements, where at least one of the floating rings (11, 21) is provided from a rigid material, or that a floating ring (13, 23) is provided on the outside of the floating rings (11, 21). 7. Farming facility (1) in accordance with one of the requirements above, where the farming facility (1) includes: - a plurality of rearing cages (10) each with its first floating devices (11) and bags (12); - one common container device (20) with a container (22); where the waste transport system (40) is configured to transport waste from the first bag (12) at the plurality of rearing cages (10) to the container (22) at the common container device (20). 8. Farming facility (1) in accordance with one of the above claims, where the bag (12) provided for storing fish (F) is made of a rigid or flexible material.