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EP-4734759-A1 - A TANK AND A MODULAR WALL ELEMENT

EP4734759A1EP 4734759 A1EP4734759 A1EP 4734759A1EP-4734759-A1

Abstract

There is provided a tank for farming aquatic organisms comprising: a first tank wall enclosing a tank space arranged to contain water and aquatic organisms to be farmed, optionally, a plurality of elongated support structures fixed onto a lateral surface of the first tank wall, an airlift pump comprising a vertical riser channel (27, 47, 57, 67), the airlift pump comprising a water outlet connected to the tank space, wherein the water outlet is configured to output aerated water into the tank space, wherein the vertical riser channel (27, 47, 57, 67) is integrally connected or integrated to the first tank wall along a height of the vertical riser channel (27, 47, 57, 67).

Inventors

  • KIURU, Tapio

Assignees

  • PaRAS Aqua Oy

Dates

Publication Date
20260506
Application Date
20240627

Claims (20)

  1. 1. A tank (10) for farming aquatic organisms comprising: - a first tank wall enclosing a tank space arranged to contain water and aquatic organisms to be farmed, - optionally, a plurality of elongated support structures fixed onto a lateral surface of the first tank wall, - an airlift pump comprising a vertical riser channel (27, 47, 57, 67), the airlift pump comprising a water outlet connected to the tank space, wherein the water outlet is configured to output aerated water into the tank space, wherein the vertical riser channel (27, 47, 57, 67) is integrally connected or integrated to the first tank wall along a height of the vertical riser channel (27, 47, 57, 67).
  2. 2. The tank (10) according to claim 1, wherein the vertical riser channel (27, 47, 57, 67) comprises a riser channel lateral surface, wherein the riser channel lateral surface either faces a lateral surface of the first tank wall or is part of the first tank wall.
  3. 3. The tank (10) according to any one of the preceding claims, wherein the vertical riser channel (27, 47, 57, 67) is fixed on the lateral surface of the first tank wall along the entire height of the vertical riser channel (27, 47, 57, 67).
  4. 4. The tank (10) according to claim any one of the preceding claims, wherein the airlift pump comprises a plurality of vertical channels, wherein a lateral surface of each vertical channel faces a lateral surface of the first tank wall or is part of the first tank wall.
  5. 5. The tank (10) according to any one of the preceding claims, wherein a plurality of elongated support structures is fixed onto a lateral surface of the first tank wall.
  6. 6. The tank (10) according to any one of the preceding claims, wherein one or several vertical channel(s) of the airlift pump is/are configured to provide structural integrity to the first tank wall.
  7. 7. The tank (10) according to any one of the preceding claims, wherein the vertical riser channel (27, 47, 57, 67) comprises, in its lower part, an air inlet (53, 173, 183, 193) configured to receive compressed air and a water inlet configured to receive tank water, and the vertical riser channel (27, 47, 57, 67) comprises, in its upper part, a riser channel outlet or outlets configured to output aerated water and air.
  8. 8. The tank (10) according to any one of the preceding claims 4 to 6, wherein said plurality of vertical channels comprise a vertical riser channel (27, 47, 57, 67) and, upstream of the vertical riser channel (27, 47, 57, 67), a water inlet channel (26, 46, 56, 66), wherein an outlet in a lower part of the water inlet channel (26, 46, 56, 66) is connected to the water inlet of the vertical riser channel (27, 47, 57, 67), and wherein the water inlet channel (26, 46, 56, 66) comprises, in its upper part, an inlet configured to receive tank water into the water inlet channel (26, 46, 56, 66), and preferably said inlet is in the form of a grid (21, 31, 51, 61, 171, 181, 191).
  9. 9. The tank (10) according to any one of the preceding claims 4 to 7, wherein said plurality of vertical channels comprise a vertical riser channel (27, 47, 57, 67) and, downstream of the vertical riser channel (27, 47, 57, 67), a water outlet channel (28, 48, 58, 68), wherein the outlet of the vertical riser channel (27, 47, 57, 67) is connected to an inlet in an upper part of the water outlet channel (28, 48, 58, 68), and wherein the water outlet channel (28, 48, 58, 68) comprises one or more water outlets configured to output aerated water into the tank.
  10. 10. The tank (10) according to any one of the preceding claims, wherein the water outlet channel (28, 48, 58, 68) comprises a gas inlet, such as an oxygen gas inlet.
  11. 11. The tank (10) according to any one of the preceding claims, wherein the water outlet channel (28, 48, 58, 68) has a downward widening shape.
  12. 12. The tank (10) according to any one of the preceding claims, wherein the vertical riser channel (27, 47, 57, 67) has an upward widening shape.
  13. 13. The tank (10) according to any one of the preceding claims 8 to 11, wherein at least some of the water outlets are arranged to provide a flow of aerated water in a perpendicular direction with regard to the first tank wall, and/or wherein at least some of the water outlets are arranged to provide a flow of aerated water in a substantially parallel or tangential direction with regard to the first tank wall.
  14. 14. The tank (10) according to any one of the preceding claims 8 to 12, wherein the water outlets are distributed across a vertical dimension of the water outlet channel (28, 48, 58, 68).
  15. 15. The tank (10) according to any one of the preceding claims 4 to 13, wherein said plurality of vertical channels comprise, as a cascade in the direction of water flow: a water inlet channel (26, 46, 56, 66), a vertical riser channel (27, 47, 57, 67), and a water outer channel (28, 48, 58, 68).
  16. 16. The tank (10) according to any one of the preceding claims, wherein said elongated support structures comprise hollow beams configured to reinforce the first tank wall.
  17. 17. The tank (10) according to any one of the preceding claims, comprising: - a second tank wall enclosing the first tank wall, - an inner space defined by the first tank wall and the second tank wall, wherein the elongated support structures are disposed within the inner space, wherein the airlift pump or at least the vertical riser channel (27, 47, 57, 67) thereof is disposed within the inner space.
  18. 18. The tank (10) according to claim 17, wherein the plurality of elongated support structures comprises a plurality of planar plates joining the first and the second tank walls to each other, and wherein the planar plates are configured to provide reinforcing connections between the first tank wall and the second tank wall.
  19. 19. The tank (10) according to claim 18, wherein - the airlift pump comprises a second plurality of planar plates, each being attached to the first tank wall and to the second tank wall, - the second plurality of planar plates are arranged so that at least one vertical channel is formed within the inner space, - said at least one vertical channel comprises a channel that is configured to function as the vertical riser channel (27, 47, 57, 67) of the airlift pump.
  20. 20. The tank (10) according to any of claims 17 to 19, wherein the first tank wall and the second tank wall, the elongated support structures, the vertical riser channel (27, 47, 57, 67), and optionally other channels of the airlift pump are provided as an integral entity, such as in the form of a cellular panel.

Description

A TANK AND A MODULAR WALL ELEMENT FIELD [0001] The present disclosure relates to a tank with an airlift pump for recirculating aquaculture. The present disclosure also relates to a modular wall element for a tank. BACKGROUND [0002] Aquaculture, generally referred to as farming of aquatic organisms, such as fish and shellfish, under controlled conditions, is a fast-growing agricultural sector that allows for harvesting seafood for human and animal consumption. By means of aquaculture a variety of aquatic species can be produced in a cost-effective manner and with predictable yields regardless of external conditions, such as weather and/or population fluctuations. [0003] There are three main stages of water treatment in recirculation aquaculture: 1) solids removal, 2) gas exchange (carbon dioxide removal and oxygen addition), and 3) biological water purification (nitrification, and in some cases also denitrification). [0004] Partial recirculation aquaculture systems have only the first two stages, but no biological water treatment at all. [0005] All stages of water treatment are usually carried out outside the tank, as individual sub-processes. In the exchange of gases, either trickling towers or separate aeration tanks are used. In the former system, water is supplied into air, and in the latter, air into water. The space requirement of these structures is about 5% of the total area of the farm. [0006] Gas exchange systems typically account for about 10 to 20% of the investment costs. The cost of centralized gas exchange consists not only of the cost of gas exchange units and the need for a hall building about 5% larger, but also of pipelines and water pumps. [0007] The exchange of gases is the so-called first production-limiting water treatment process. That is, the removal of carbon dioxide (and the addition of oxygen) determines the need for pumping water in the entire farm. In addition to the aeration units, the pipe and pump sizes of the farm are thus significantly larger compared to a situation in which the pumping could be dimensioned according to the needs of solids removal and biological water treatment. Aeration towers or tanks are dimensioned according to the volume of the fish tanks and the planned growing densities, as well as the use of feed. If the farm is expanded, also the size of the aeration units and the size of the piping between the aeration units and the tanks must be increased, which is very challenging, as the pipelines are placed underground, below the tanks. [0008] Current technologies for fish tanks with airlift pumps involve locating the airlift pump outside the fish tank or inside the fish tank in the tank water, in both cases as a separate unit. [0009] Inside the tank, an airlift pump consumes tank space, and additionally it may disturb circulation of tank water and deteriorate tank water quality by re-suspending solid matter from the bottom of the tank. [0010] It is an aim of the present embodiments to overcome at least some of the disadvantages of known fish tanks and their gas-exchange systems. SUMMARY [0011] The invention is defined by the features of the independent claims. Some specific embodiments are defined in the dependent claims. [0012] According to a first aspect, there is provided a tank for farming aquatic organisms comprising: a first tank wall enclosing a tank space arranged to contain water and aquatic organisms to be farmed, optionally, a plurality of elongated support structures fixed onto a lateral surface of the first tank wall, an airlift pump comprising a vertical riser channel, the airlift pump comprising a water outlet connected to the tank space, wherein the water outlet is configured to output aerated water into the tank space, wherein the vertical riser channel is integrally connected or integrated to the first tank wall along a height of the vertical riser channel. [0013] According to a second aspect, there is provided A modular wall element for a tank for farming aquatic organisms, the modular wall element comprising: a first wall having a first end and a second end, optionally, a plurality of elongated support structures fixed onto a lateral surface of the first wall, an airlift pump comprising a vertical riser channel, wherein the vertical riser channel is integrally connected or integrated to the first wall along a height of the vertical riser channel, wherein the airlift pump comprises a water outlet configured to output aerated water into the tank space, wherein said ends of the modular wall element are configured to be connected to respective ends of another modular wall element so that the connected modular wall elements encase or confine at least a part of a tank space arranged to contain water and aquatic organisms to be farmed. [0014] Various embodiments of the first aspect or the second aspect may comprise one or more features from the following bulleted list: • The riser channel comprises a riser channel lateral surface, wherein the