WO1987004319A1

WO1987004319A1 - An arrangement in an enclosure for fish breeding

Info

Publication number: WO1987004319A1
Application number: PCT/NO1987/000008
Authority: WO
Inventors: Wilfred Astord FLO^/LO; Cyril Blavins
Original assignee: Floelo Wilfred Astord; Cyril Blavins
Priority date: 1986-01-23
Filing date: 1987-01-22
Publication date: 1987-07-30
Also published as: NO158201B; NO860243L; NO158201C; EP0260272A1

Abstract

An enclosure (1) for breeding fish, said enclosure at its upper side wall portion (2a) is secured to an upper buoyancy or floating frame (3a). The lower side wall portion (2b) of enclosure (1) is secured to a liftable and lowerable frame (5) for lifting the bottom (1a) of said enclosure (1) from its immersed position in the water to an upper position in the water, to facilitate catching operations of bred fish, and maintenance of the sheet/net material of said enclosure. Guide means (6) for centration of frames comprise guide stay means (6a) attached to lower frame (5) and passing through guide sleeves (6b) in said upper floating frame (3a). The bottom (1a) of said enclosure consists of a rigid plate having a central portion (1a') being lower than the marginal portions to collect sediment that is removed by the aid of a device (7) to a purification plant.

Description

AN ARRANGEMENT IN AN ENCLOSURE FOR FISH BREEDING

The present invention relates to an arrangement in an en¬ closure having flexible side walls, for fish breeding, and .5 being of the kind as stated in the introductory part of the following independent claim 1.

A series of different embodiments of enclosures for breeding fish at sea is known and used, being of the above mentioned

10 kind with the actual enclosure consisting of a bag shaped fishing net material that is stretched and fastened to a floating frame in the water. Said frame, forms a catwalk or a work-place, or the actual frame may be constructed as buoyancy members supporting such a catwalk or work-place

₁5 around the upper edge of said enclosure.

When fishes are harvested, i.e. caught, from such an enclos¬ ure a landing net is commonly used for catching one or a number of fishes at a time, depending on their size. With an

20 enclosure of the kind mentioned above fish feed is supplied onto the water surface to sink and be eaten by the fishes. Excess feed and faeces from the fish will sink down through the meshes of said fishing net to the bottom of said enclos¬ ure and will collect on the sea bottom at the very locality

25 of the enclosure, or sink to the bottom elsewhere if the current is strong enough to carry the waste away.

The structure of enclosures for breeding fish, thus, has dis¬ advantages, both in connection with catching the fish, and in ₃₀ connection with pollution of the environment, and it is also difficult as regards maintenance, both as to cleaning the walls of the enclosure, and as to repair work when damaged.

_*

It is an object of the present invention to provide an arr- 35 angement in an enclosure of the above mentioned kind, which will facilitate the catching operation as well as maintenance of the shee /net material of the enclosure, and by which poll¬ ution of the sea surrounding the enclosure. is eliminated, or essentially reduced. Furthermore, with the invention undesir¬ able parasites which may harm the breeding fish in the enclos¬ ure should be kept out.

The above mentioned object is achieved according to the in¬ vention by the aid of the characterizing features stated in the characterizing part of the following independent claim 1, as well as in the remaining dependent claims.

The invention will be disclosed in more detail below, with reference to an embodiment shown in the drawing, where

Figure 1 shows the enclosure in a normal breeding state with a submersed- bottom, and Figure la shows an alternative embodi- ment of the same,

Figure 2 shows said enclosure with its bottom lifted for catching fish, or checking and/or repairing the bottom and/ or side walls of the enclosure, respectively, and a possible device for removing deposits.

In the drawing Figure 1 shows an enclosure 1 Itaving flexible side walls 2 made from a material that may, e.g. be a perfor¬ ated plastic sheet or a net having meshes, with the resulting openings in a plastic sheet or in a net are, preferably dimensioned to keep^"undesirable parasites that may harm the fish out of the enclosure.

The upper side wall portion 2a of side walls 2 is secured to buoyancy members 3, e.g. in the shape of an upper floating frame 3a carrying/forming a catwalk/work place 4 which extends all along the upper side wall portion 2a of the enclosure around the entire top of enclosure 1. On said face 4 at least one fence 4a is provided on the edge qf said face toward the opening of said enclosure, and said^' fence may, if desired, be provided with a net to prevent the fish from leaping out of the enclosure. The lower side wall portion 2b of enclosure 1 is secured to a liftable and lowerable frame 5 for lifting bottom la of en¬ closure 1 from its submersed position in the sea to an upper position in the water, inter alia to facilitate catching of breeding fish, and maintenance of the sheet/net material of said enclosure.

Lower liftable and lowerable frame 5 is connected with upper floating frame 3a via guide means 6 for cetering said frames 3a and 5 when lower frame 5 is lifted to its upper porition. Said guide means 6 comprise guide stay members 6a which in the shown embodiment are secured to lowermost frame 5, and run through guide sleeves or the like in upper floating frame 3a. Enclosure 1 and frames 3a and 5 are preferably rectangular, as shown in the drawing, and guide stay means 6a, and guide sleeves 6b are, preferably, placed in the corners of said frames.

Lower frame 5 comprises at least one, and preferably a number of water compartments. By pumping air into one or several water compartments it is possible to lift frame 5, and thus, the bottom la of said enclosure to a desired harvesting posit¬ ion, depending on the number of fishes in said enclosure, if desired up to upper frame 3a.

Bottom la of said enclosure, preferably and as shown in the drawing, consists of a rigid plate which is inclined from the side walls 2 and frame 5 of enclosure 1 to its central portion la' being provided with a device 7 for removal of precipitates in the shape of faeces and excess feed. Due to the inclination of bottom plate la towards its central portion la¹ precip¬ itates will tend to collect in said central bottom portion la¹ , which may be provided with an opening, not shewn, which is connected with a suction hose (not shown) for precipitates that are preferably pumped to a purifying plant ashore, or to the purifying plant on a platform in connection with a group of enclosures 1. The purified water can, thus, run out into the sea, whereas the separated more or less solid mass of precipitates is taken ashore for further treatment and for conversion into soil improving matter.

To facilitate cleaning of bottom plate la lower frame 5 may be provided with rinsing nozzles 8 directed towards the central portion of bottom la along the bottom surface. Precipitates will, thus, be washed towards central portion la of the bottom with its removal means 7.

To clean the side walls 2 of said enclosure upper frame 3a may be provided with rinsing nozzles 9 which are directed downward along the inside of side walls 2 of the enclosure 1 for washing down organisms or impurities that adhere to the_ insides of said side walls 2.

Said removal means 7, as shown in Figure 1, comprises a suction head 7a with a hose 7b extending along said bottom sur- face la to one of said guide stay means 6a, and extending up through said means to a not shown suction pump and conveyance to a purification plant.

Suction head 7a may, obviously, be connected with a hose 7b extending freely up to the top of said enclosure and to a suction pump and a purification plant.

Supply of fresh water in addition to the natural exchange of water through the- side walls of said enclosure, and if desired, supply of water having a desired temperature in relation to the surrounding water may be achieved in a manner known per se and will not be disclosed in more detail here.

By the aid of the arrangement in connection with an enclosure as mentioned above, it is achieved,^" in addition to the practical advantages in connection with catching fish, and possibly, maintenance of the side walls of said enclosure, that feed residues and faeces are collected in the enclosure and are precipitated on the bottom where precipitated matter is collected by the aid of removal means 7. This means that fish breeding may be carried out at sea without pollution of the close environment.

In an alternative embodiment as shown in Figure 1, said guide means 6 between said lower liftable and lowerable frame 5 and upper floating frame 3a consists of anchoring wires 10 having anchoring weights 11 at their lower end, or anchors, with said anchoring wires secured to the corners of said rectangular upper floating frame 3a. Said anchoring wires extend through guides 12 in the corners to said liftable and lowerable frame 5, so that said frame 5 will be guided and kept in place by anchoring wires 10 wh.en it is lifted and lowered, respectively.

In order to achieve correct mutual positions of guide portions 10a of anchoring wires 10 for frame 5 said anchor¬ ing wires are attached to a frame 13 beneath said liftable and lowerable frame 5 in such a manner that said guide port¬ ions 10a of anchoring wire 10 extend in parallel from upper floating frame 3a to said frame 13 which may have the shape of a cross consisting of H-profiles that are welded together. From frame 13 to which anchoring wire 10 is secured said wires extend down to anchoring block 11 on the bottom of_- the sea. In this manner the above mentioned guide means 6 with guide stay members 6a, as shown in the first disclosed embodiment of Figure 1 is simplified.

Claims

1. An arrangement in connection with an enclosure (1) for breeding fish and having flexible side walls (2), with said enclosure (1) being at its upper side wall portion (3a) secured to buoyancy means (3), e.g. in the shape of an upper floating frame (3a)_. carrying/constituting a catwalk/work- surface (4) which extends along the upper side wall portion (2a) of said enclosure, preferably all around said enclosure (1), c h a r a c t e r i z e d i n that lower side wall portion (2b) of said enclosure (1) is secured to a liftable and lowerable frame (5) for lifting the bottom (la) of said enclosure (1) from a submersed position in the water to an upper position in the water, inter alia, to facilitate the catching operation of the bred fish as well as maintenance of the sheet/net material of said enclosure.

2. An arrangement as defined in claim 1, c h a r a c t e r i z e d i n that said lower liftable and lowerable frame (5) is connected with said upper floating or buoyancy frame (3a) via guide means (6) for centration of frames (3a,5) when lower frame (5) is lifted to its upper position.

3. An arrangement as defined in claim 2, c h a r a c t e r i z e d i n that said guide means (6) comprise guide stay members (6a) which are connected to be axially movable with at least one of said frames.

4. An arrangement as defined in claim 3, c h a r a c t e r i z e d i n that said guide stay mem¬ bers (6a) are secured to said lower frame (5) and extend through guide sleeves (6b) in said upper floating frame (3a).

5. An arrangement as defined in any of the preceding claims, c h a r a c t e r i z e d i n that said lower frame (5) comprises at least one water compartment for lift¬ ing said frame (5) and, thus, the bottom (la) of said enclos¬ ure by evacuating water in said enclosure(s) .

6. An arrangement as defined in one of claims 1-5, c h a r a c t e r i z e d i n that the bottom (la) of said enclosure consists of a rigid plate inclining from the side walls (2) of said enclosure (1) down to its central portion (la¹) which is provided with a means (7) for removal of deposited matter in the form of faeces and excess feed.

7. An arrangement as defined in claim 6, c h a r a c t e r i z e d i n that said lower frame (5) comprises rinsing nozzles (8) which are directed toward the central portion of said bottom (la) along the bottom surfaces.

8. An arrangement as defined in claim 6, c h a r a c t e r i z e d i n that said upper frame (3a) comprises rinsing nozzles (9) which are directed downwards along the inside of side walls (2) of said enclosure (1).

9. An arrangement as defined in claim 1, c h a r a c t e r i z e d i n that side walls (2) of said enclosures (1) consist of a perforated plastic sheet or a net with openings or meshesh dimensioned to keep out undes¬ irable parasites which might harm the bred fish. ^•

10. An arrangement as defined in claim 1, c h a r a c t e r i z e d i n that guide means (6) con¬ sist of anchoring wires (10) which are secured to upper float¬ ing frame (3a) and to anchoring means (11) on the bottom of the sea, and that said anchoring wires (10) pass through guides in lower liftable and lowerable frame (5), said anchoring wires (10), if desired, being kept mutually in parallel with their upper guide portions (10a) by the aid of a frame (13) provided below frame (5) and fastened to said anchoring wires (10).