NO346321B1 - Oxygen supply for breeding tanks in fish farms - Google Patents
Oxygen supply for breeding tanks in fish farms Download PDFInfo
- Publication number
- NO346321B1 NO346321B1 NO20210080A NO20210080A NO346321B1 NO 346321 B1 NO346321 B1 NO 346321B1 NO 20210080 A NO20210080 A NO 20210080A NO 20210080 A NO20210080 A NO 20210080A NO 346321 B1 NO346321 B1 NO 346321B1
- Authority
- NO
- Norway
- Prior art keywords
- water
- column
- gas
- oxygen
- output
- Prior art date
Links
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 title claims description 55
- 239000001301 oxygen Substances 0.000 title claims description 55
- 229910052760 oxygen Inorganic materials 0.000 title claims description 55
- 241000251468 Actinopterygii Species 0.000 title claims description 13
- 238000009395 breeding Methods 0.000 title description 2
- 230000001488 breeding effect Effects 0.000 title description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 82
- 239000007789 gas Substances 0.000 claims description 64
- 238000000034 method Methods 0.000 claims description 13
- 238000006213 oxygenation reaction Methods 0.000 claims description 5
- 230000001276 controlling effect Effects 0.000 claims description 4
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 3
- 230000001105 regulatory effect Effects 0.000 claims description 3
- 229910001882 dioxygen Inorganic materials 0.000 claims description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 10
- 235000019688 fish Nutrition 0.000 description 10
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- 230000000694 effects Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 230000001706 oxygenating effect Effects 0.000 description 2
- 241000972773 Aulopiformes Species 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 235000019515 salmon Nutrition 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01K—ANIMAL HUSBANDRY; CARE OF BIRDS, FISHES, INSECTS; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
- A01K63/00—Receptacles for live fish, e.g. aquaria; Terraria
- A01K63/04—Arrangements for treating water specially adapted to receptacles for live fish
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01K—ANIMAL HUSBANDRY; CARE OF BIRDS, FISHES, INSECTS; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
- A01K63/00—Receptacles for live fish, e.g. aquaria; Terraria
- A01K63/04—Arrangements for treating water specially adapted to receptacles for live fish
- A01K63/042—Introducing gases into the water, e.g. aerators, air pumps
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/20—Mixing gases with liquids
- B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
- B01F23/232—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using flow-mixing means for introducing the gases, e.g. baffles
- B01F23/2322—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using flow-mixing means for introducing the gases, e.g. baffles using columns, e.g. multi-staged columns
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/20—Mixing gases with liquids
- B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
- B01F23/232—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using flow-mixing means for introducing the gases, e.g. baffles
- B01F23/2323—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using flow-mixing means for introducing the gases, e.g. baffles by circulating the flow in guiding constructions or conduits
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/20—Mixing gases with liquids
- B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
- B01F23/237—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids characterised by the physical or chemical properties of gases or vapours introduced in the liquid media
- B01F23/2376—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids characterised by the physical or chemical properties of gases or vapours introduced in the liquid media characterised by the gas being introduced
- B01F23/23761—Aerating, i.e. introducing oxygen containing gas in liquids
- B01F23/237612—Oxygen
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/40—Mixing liquids with liquids; Emulsifying
- B01F23/45—Mixing liquids with liquids; Emulsifying using flow mixing
- B01F23/454—Mixing liquids with liquids; Emulsifying using flow mixing by injecting a mixture of liquid and gas
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/20—Measuring; Control or regulation
- B01F35/21—Measuring
- B01F35/211—Measuring of the operational parameters
- B01F35/2112—Level of material in a container or the position or shape of the upper surface of the material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/20—Measuring; Control or regulation
- B01F35/22—Control or regulation
- B01F35/221—Control or regulation of operational parameters, e.g. level of material in the mixer, temperature or pressure
- B01F35/2211—Amount of delivered fluid during a period
Description
OXYGEN SUPPLY FOR BREEDING TANKS IN FISH FARMS.
This invention relates to a system for automatic regulation of oxygen supply in fish farms such as salmon farms, or other applications where water with a required oxygen content is present.
Oxygen level in hatcheries and breeding trays is important for producing healthy and well-fed fish or fry. In extreme cases an insufficient oxygen level can cause the fish to die. Although well-known also from natural processes the problem is becoming more important as many fish farms are interested in moving the farms to land based and controlled environments instead of farms in open water.
In order to deal with the problem, the industry has used processes for enriching the water with oxygen, e.g. as discussed in US5904851, US10772308 NO325432, NO342696 and US2012/0234254. According to one known solution referred to in US2009/0166300 water is pumped into a column from the top along with pure oxygen and through turbulence or diffusion the oxygen and water is mixed down through the column so that oxygen rich water may be extracted from the bottom and be introduced into the trays.
A problem with the known art is that process takes time and may not be able to handle quick changes in the oxygen content of the water, for example when feeding the fish, as the increased activity of the fish will also increase the use of oxygen.
It is therefore an object of the present invention to provide a means for increasing the flexibility of the system to handle fast changes based on existing equipment so that the cost of the system is not significantly increased. These objects are obtained as specified in the accompanying claims.
Specifically, the present invention provides an improvement over the concept described in US2009/0166300, adding additional features providing faster increase or adjustment of the oxygen level, without large increase in the cost of the system. Although the gas from the gas pocket may contain other gases than oxygen coming from the water, the gas introduced at the column outlet will be at atmospheric pressure and will not affect the water quality. For example the nitrogen content in the supplied gas from the pocket will be significantly less than the natural nitrogen of the air.
The invention will be described more in detail below referring to the accompanying drawings, illustrating the invention by way of examples.
Figure 1 illustrates the system according to a preferred embodiment of the invention.
The system illustrated in figure 1 shows a pump 1 pumping water to be oxygenated through a pipe 2 to the top of a mixing column 3. At the top of the column a diffusor is shown at the input 4 for introducing oxygen into the flow entering the column. The oxygen input 4 is connected to a well known oxygen supply preferably being capable of adjusting or closing the oxygen supply. At the bottom of the column 3 a further pipe 5 is connected for leading the oxygen enriched water into the tray, tank, pipe or similar 10. As is known in the prior art the water may be retrieved and lead back into the same tank. If the water is retrieved form a pipe the pump 1 may be connected to the pipe upstream from the output back into the pipe 10.
As is described in US2009/0166300, referring to reference numbers in the present figure 1, the mixing column will usually contain a gas pocket 12 at the top of the column containing a mixture of oxygen that has not been dissolved in the water 13 as well as a small amount of nitrogen or other gases diffusing from the water. Thus, a certain water level 11 is in a position in the tank. According to the present invention a gas outlet valve 6 is connected to a pipe 7 leading gas from the gas pocket 12 to an output 8 in the column outlet 5. The column according to the present invention may also include a security valve 9 for evacuating gas from the pocket. In addition to the shown features the system may include sensors for measuring the oxygen content in the water but in general the system should be capable of operating automatically without intrusion.
Under normal operation of the present invention, the pump 1 will operate at a predetermined pump rate and a controlled amount of oxygen is supplied through the oxygen input 4. The pump rate may be given by the absorption rate of the water and/or the frequency of evacuation of accumulated nitrogen/residual gasses though the evacuation valve 9. A sensor may be used for measuring the pressure difference between the top and bottom of the column, may measure the size of the gas volume 12 or the water level 11 in the column. One possibility for measuring the water level is by measuring the pressure difference between the gas pocket output 6 and position 16 at the bottom of the column, in figure 1 connected to the gas pocket output 6 through a pipe 15 which may include means for measuring the water level. If the gas volume 12 becomes too small the water supply into the column will preferably be reduced or stopped using pump 1 while continuing the oxygen supply, and if the gas pocket 12 becomes to large the oxygen supply will be closed with the input valve 4.
According a preferred embodiment the oxygen content of the output water may be adjusted directly by opening the valve 6 leading gas directly from the gas volume 12 into the output water flowing in the output pipe 5 into the tank. This may reduce the size of the gas volume which will activate the processes increasing the size, e.g. by stopping the water supply into the column.
This way an improved system has been provided being capable of automatic regulation of the oxygen content in the supplied water. Initially the oxygenated water has a relatively stable O2 saturation because of the saturation effect and saturation curve given stable gas pressure and gas composition in the gas pocket on top of the column, which leads to an essentially linear process response characteristic that the regulation algorithm of the system can handle.
As the volume flow of oxygenated water may be supplied to the tray by regulating the electrically actuated valve 6 connected to the gas pocket 12 and to the outlet 5 it is possible according to the invention to provide fast changes in the oxygen content.
The supply of clean oxygen, through opening and closing an magnetic valve at the oxygen input 4. Evacuating accumulated nitrogen is provided in the gas pocket 12 in the top of the column and may be performed sporadically at a frequency dependent evacuation to the tank by opening the magnetic valve 9.
This way the system has a O2 boost/afterburner function making it possible for the system to increase the evacuation rate using the gas pocket when the column has already reached its full capacity by supplying oxygen from the pocket directly into the output water. This supplementary oxygenation will then be performed at low pressure oxygenation.
It is also possible to use the system to adjust the output oxygen level at chosen time periods, for example at a time of day when a temporary reduction in the oxygen level in the tank is expected so as to balance the reduction by increasing the supplied oxygen level. This may for example be at the time when the fish in a tank is fed. Then the oxygen level may be increased by 5-10%. This will reduce the reduction in the oxygen level stressing the fish.
Although the drawings show a single column connected to one water volume for increasing the oxygen level in that column it is possible to connect the column output to two or more water volumes with separate gas pocket output valves 6 and/or output valves 8 for individual control of the oxygen level in each water volume.
The preferred position of the gas output 8 in the output pipe will depend on the situation. By positioning it close to the column the injected low pressure gas will have time to mix into the output water before being injected into the water volume 10
On the other hand it can be advantageous to position the low pressure gas outlet 8 close to the water outlet into the water volume 10 if the system fails as this will provide a possibility to add oxygen into the main volume even if the column has stopped working.
To summarize the present invention relates to a system and method for oxygenating water, especially relating to fish farms and similar system requiring a certain control of the oxygen level in a body of water. The system includes a water pump connected to a pipe with an output in the upper part of a vertical mixing column. The pump is configured to pump water into said column through a water inlet at the upper part of the mixing column. The column also includes a connector providing an inlet for receiving oxygen from an oxygen supply. The oxygen inlet may be positioned inside the water inlet, in the water pipe close to the inlet, or directly into the column top.
The column 3 is configured to contain a gas pocket 12 in said upper part, the size of which being defined as a function of water and oxygen flow into the column and the flow out of the column, and the lower part includes an output pipe 5 leading oxygenated water to a receiver tank such as a fish tank 10.
According to the invention upper part of the column 3 includes a gas outlet 6 connected to a gas pipe, where the gas outlet is positioned in communication with the gas pocket 12. the gas pipe being connected to a controlled valve 6 and to said water outlet 18, thus being configured for controlled supply of gas from said gas pocket to the water at said water outlet 18 for increasing the oxygen level at the water outlet. The water outlet may include a nozzle (not shown) for ejecting the oxygen enriched water into the water volume 10.
The system also may include a pressure outlet 9 in said upper part for regulating the gas pressure in the gas pocket.
The pump is preferably configured to run on a constant rate, and the water inlet includes a valve 17 configured to stop the water flow from the pipe under predetermined conditions, or alternatively the pump may be stopped under such conditions.
The system may also include a sensor 6,15,17 for measuring a parameter relating to the water level 11 in the column, such as the pressure difference between the top and bottom of the column or the pressure in the gas volume, and be configured to stop said water flow when the water level is above a predetermined threshold.
The method according to the invention may be described, referring to the system above, as a method for controlling the oxygen level in a water flow in a system including a column shaped tank having an input at a top and an output at the bottom. The method includes the steps of:
- introducing water and oxygen gas into said column top column at a rate providing a gas pocket on top of said column essentially constituted by oxygen,
- providing movement in said column dissolving said oxygen into said water, and
- letting the oxygenated water out at said column output.
The method further includes the step of:
- through a gas output at the column top in communication with the gas pocket leading gas from said pocket to said column output, thus providing an additional oxygenation of the water at said output.
The size of the gas pocket is measured and controlled by adjusting said gas pocket size by controlling the rate of water and/or oxygen being introduced into the column, evacuating gas from the gas pocket through a valve and/or conducting the gas from the pocket to the column output for further oxygenating the output water.
Claims (7)
1. Water oxygenation system, especially for fish farms, the system including a water pump (1) connected to a pipe (2) with an output in the upper part of a vertical mixing column (3), the pump being configured to pump water into said column, the upper part of the mixing column also including a connector (4) for receiving oxygen from an oxygen supply, the column being configured to have a gas pocket (12) in said upper part, and wherein the lower part includes an output pipe (5,18) leading oxygenated water to a receiver tank (10) such as a fish tank, and
characterised in that the upper part of the column (3) includes a gas outlet (6) connected to a gas pipe (7), the gas pipe being connected to a controlled valve (8) and to said water outlet (5,18), thus being configured for controlled supply of gas from said gas pocket (12) to said water outlet (5,18) for increasing the oxygen level at the water outlet.
2. System according to claim 1, including a pressure outlet (9) in said upper part for regulating the gas pressure in the gas pocket (12).
3. System according to claim 1, wherein the pump (1) is configured to run on a constant rate, said water pipe inlet including a valve (4) configured to stop the water flow from the pipe (2) under predetermined conditions.
4. System according to claim 3, wherein the system includes a sensor (6,15,17) for measuring a parameter relating to the water level (11) in the column (3) and being configured to stop said water flow when the water level is above a predetermined threshold.
5. System according to claim 4, wherein parameter is the pressure in the gas pocket (12).
6. Method for controlling the oxygen level in a water flow in a system including a column shaped tank (3) having an input at a top and an output at the bottom, the method including the steps of:
- introducing water and oxygen gas into said column top column at a rate providing a gas pocket (12) on top of said column essentially constituted by oxygen,
- providing movement in said column dissolving said oxygen into said water,
- letting the oxygenated water out at said column output (5,18),
characterised by including the step of:
- through a gas output (6) at the column top in communication with the gas pocket (12) leading gas from said pocket to said column output (5,18), thus providing an additional oxygenation of the water at said output.
7. Method according to claim 6, wherein the size of the gas pocket (12) is measured and adjusting said gas pocket size by controlling the rate of water and/or oxygen being introduced into the column.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NO20210080A NO346321B1 (en) | 2021-01-21 | 2021-01-21 | Oxygen supply for breeding tanks in fish farms |
| PCT/EP2022/051332 WO2022157301A1 (en) | 2021-01-21 | 2022-01-21 | Oxygen supply for breeding tanks in fish farms |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NO20210080A NO346321B1 (en) | 2021-01-21 | 2021-01-21 | Oxygen supply for breeding tanks in fish farms |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| NO20210080A1 NO20210080A1 (en) | 2022-06-07 |
| NO346321B1 true NO346321B1 (en) | 2022-06-07 |
Family
ID=80050700
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO20210080A NO346321B1 (en) | 2021-01-21 | 2021-01-21 | Oxygen supply for breeding tanks in fish farms |
Country Status (2)
| Country | Link |
|---|---|
| NO (1) | NO346321B1 (en) |
| WO (1) | WO2022157301A1 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI2940A (en) * | 1907-04-16 | For the purpose of regeneration of water and wood, the whole of the fiscar, the occupant and the other genome | ||
| NO325432B1 (en) * | 2006-08-21 | 2008-04-28 | Akvator As | Method and apparatus for adjusting gas content in water |
| US20090166300A1 (en) * | 2004-05-25 | 2009-07-02 | Gregory Scott Osborn | System and method for dissolving gases in fluids and for delivery of dissolved gases |
| NO342696B1 (en) * | 2006-07-13 | 2018-07-09 | Institut Nat Des Sciences Appliquees | A method and installation for treating an aqueous drain for the purpose of extracting at least one dissolved gas compound therefrom; for use in aquaculture in a recycled aqueous environment |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US342696A (en) | 1886-05-25 | Force-pump | ||
| US325432A (en) | 1885-09-01 | Cultivator | ||
| US4211733A (en) * | 1978-12-26 | 1980-07-08 | Chang Shih Chih | Gas-liquid mixing process and apparatus |
| US5904851A (en) | 1998-01-19 | 1999-05-18 | Life International Products, Inc. | Oxygenating apparatus, method for oxygenating liquid therewith, and applications thereof |
| US6530895B1 (en) * | 2000-01-25 | 2003-03-11 | Life International Products, Inc. | Oxygenating apparatus, method for oxygenating a liquid therewith, and applications thereof |
| US6464210B1 (en) * | 2002-03-22 | 2002-10-15 | Agrimond, Llc | Fluid dissolution apparatus |
| CN102256640A (en) | 2008-12-16 | 2011-11-23 | 溶液充氧公司 | Improvements in oxygenation of a fluid |
| CL2017001776A1 (en) | 2017-07-04 | 2017-10-06 | Garín Guillermo Octavio Bronstein | Water treatment and recirculation system to restore water quality to optimum levels in freshwater or saltwater fish cages |
-
2021
- 2021-01-21 NO NO20210080A patent/NO346321B1/en unknown
-
2022
- 2022-01-21 WO PCT/EP2022/051332 patent/WO2022157301A1/en active Application Filing
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI2940A (en) * | 1907-04-16 | For the purpose of regeneration of water and wood, the whole of the fiscar, the occupant and the other genome | ||
| US20090166300A1 (en) * | 2004-05-25 | 2009-07-02 | Gregory Scott Osborn | System and method for dissolving gases in fluids and for delivery of dissolved gases |
| NO342696B1 (en) * | 2006-07-13 | 2018-07-09 | Institut Nat Des Sciences Appliquees | A method and installation for treating an aqueous drain for the purpose of extracting at least one dissolved gas compound therefrom; for use in aquaculture in a recycled aqueous environment |
| NO325432B1 (en) * | 2006-08-21 | 2008-04-28 | Akvator As | Method and apparatus for adjusting gas content in water |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2022157301A1 (en) | 2022-07-28 |
| NO20210080A1 (en) | 2022-06-07 |
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