Culture facility and dissolved oxygen concentration adjustment method

Abstract

To provide a culture facility that can cope with a change in a dissolved oxygen concentration in water stored in a water tank.SOLUTION: A culture facility according to an aspect of the present disclosure comprises a water tank for storing water for culture, an oxygen dissolution device for internally dissolving oxygen in supply water to be supplied to the water tank, and an aeration device for releasing oxygen into stored water stored in the water tank.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to aquaculture equipment and a method for adjusting the dissolved oxygen concentration.

Background Art

[0002] As a technology related to aquaculture equipment, Patent Document 1 discloses a method of mechanically dissolving pure oxygen in the same water as the breeding water with an oxygen dissolution device, injecting the dissolved high-concentration oxygen water into the breeding water, and breeding fish and shellfish. By using the oxygen dissolution device described in Patent Document 1, the breeding efficiency of aquaculture equipment can be improved.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The dissolved oxygen concentration of the stored water in the water tank varies depending on the activity state of the aquatic organisms to be cultured and external factors. When the variation in the dissolved oxygen concentration is small, the dissolved oxygen concentration of the stored water can be made to follow the target value only by controlling the oxygen dissolution device, but when the variation in the dissolved oxygen concentration is large, there is a possibility that it cannot be dealt with.

[0005] Therefore, an object of the present disclosure is to provide aquaculture equipment capable of coping with changes in the dissolved oxygen concentration of the water stored in the water tank.

Means for Solving the Problems

[0006] The aquaculture equipment according to one aspect of the present disclosure includes a water tank for storing water for aquaculture, an oxygen dissolution device for internally dissolving oxygen in the supply water supplied to the water tank, and an aeration device for releasing oxygen into the stored water stored in the water tank.

Effects of the Invention

[0007] According to the above configuration, it is possible to provide an aquaculture facility capable of corresponding to changes in the dissolved oxygen concentration of the water stored in the water tank.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0009] (Overall Configuration) Hereinafter, the aquaculture facility 100 according to the embodiment will be described. First, the overall configuration of the aquaculture facility 100 will be described. FIG. 1 is a schematic diagram of the aquaculture facility 100. As shown in FIG. 1, the aquaculture facility 100 according to the present embodiment includes a water tank 11, a dissolved oxygen concentration meter 12, an oxygen dissolution device 13, an aeration device 14, and a control device 15. Hereinafter, these components will be described in order.

[0010] <Water Tank> The water tank 11 is a part for accommodating the aquatic organisms to be cultured. In the present embodiment, the aquatic organisms are fish. The water tank 11 may be installed on land or in water. When the water tank 11 is installed in water, the water tank 11 partitions the inside from the surrounding water. In the water tank 11, the entry and exit of water between the outside and the inside are restricted. Also, the material and shape of the water tank 11 are not limited. For example, the water tank 11 may be formed of plastic or glass. Also, the water tank 11 may be formed of a plate-shaped member or a sheet-shaped member. The water tank 11 stores seawater or fresh water according to the type of the aquaculture target. That is, the water for aquaculture may be seawater or fresh water. The water in the water tank 11 may be taken in from a water source such as the sea or a river, or all or part of the water in the water tank 11 may be circulated and reused.

[0011] Water is continuously supplied to the water tank 11 under pressure by a pump (not shown) from the supply line 21, and the water in the water tank 11 is continuously discharged to the outside through the discharge port 22. Thereby, the water for aquaculture stored in the water tank 11 is continuously replaced. However, the water for aquaculture stored in the water tank 11 does not necessarily have to be continuously replaced, and may be replaced, for example, at regular intervals. Hereinafter, the water supplied to the water tank 11 is referred to as "supply water", and the water stored in the water tank 11 is referred to as "stored water". In the present embodiment, the flow rate of the supply water is constant, but the flow rate of the supply water may be varied.

[0012] <Dissolved oxygen meter> The dissolved oxygen meter 12 is a device that measures the dissolved oxygen concentration of the stored water. The dissolved oxygen meter 12 is electrically connected to a control device 15 described later, and a measurement signal of the dissolved oxygen meter 12 is transmitted to the control device 15. The dissolved oxygen concentration of the stored water may vary greatly depending on the activity state of the aquaculture target and external factors.

[0013] <Oxygen dissolution device> The oxygen dissolution device 13 is a device that dissolves oxygen in the supply water inside. The oxygen dissolution device 13 is located in the supply line 21. The outlet 23 of the supply line 21 is arranged inside the water tank 11. The supply water in which oxygen is dissolved by the oxygen dissolution device 13 is supplied to the water tank 11 through the outlet 23 of the supply line 21. The oxygen dissolution device 13 includes an oxygen dissolution device main body 26 and an oxygen flow rate adjustment valve 27.

[0014] The oxygen dissolution device main body 26 dissolves oxygen in the supply water taken in from the supply line 21 inside, and returns the supply water after oxygen dissolution to the supply line 21. The oxygen dissolution device main body 26 may be, for example, a method of dissolving oxygen in the supply water by extruding the supply water like a water jet using a screw or the like, a method of supplying small bubbles / microbubbles to the supply water, or a method of passing the refined supply water through the space of high-pressure oxygen. In the oxygen dissolution device main body 26, water with a high dissolved oxygen concentration can be efficiently generated. Note that the specific configuration of the oxygen dissolution device main body 26 is not limited. For example, the oxygen dissolution device main body 26 may mechanically dissolve oxygen in the supply water by increasing the surface area of the supply water by diffusing the supply water inside and bringing it into contact with oxygen in that state.

[0015] The oxygen flow rate adjustment valve 27 is a valve that adjusts the amount of oxygen supplied to the oxygen dissolution device main body 26. That is, by controlling the oxygen flow rate adjustment valve 27, the amount of oxygen dissolved in the supply water can be adjusted. Oxygen is supplied from the oxygen supply facility 29 to the oxygen dissolution device main body 26 via the oxygen supply line 28. For example, the oxygen supply facility 29 may be a PSA (Pressure Swing Adsorption) type oxygen gas generator. The oxygen flow rate adjustment valve 27 is located in this oxygen supply line 28.

[0016] <Aeration device> The aeration device 14 is a device that releases oxygen bubbles into the stored water. The aeration device 14 of this embodiment includes an auxiliary line 31 and an emergency line 32.

[0017] The auxiliary line 31 is a line that directly releases oxygen bubbles into the stored water. The upstream part of the auxiliary line 31 is connected to the oxygen supply facility 33, and the downstream part is located inside the water tank 11. Further, an oxygen auxiliary valve 34 is located on the auxiliary line 31. By opening this oxygen auxiliary valve 34, the oxygen supplied from the oxygen supply facility 33 is conveyed to the stored water through the auxiliary line 31 and released into the stored water. Note that the oxygen supply facility 33 that supplies oxygen to the auxiliary line 31 may be the same facility as the oxygen supply facility 29 that supplies oxygen to the oxygen dissolving device 13, or may be a different facility.

[0018] The emergency line 32 is a line that directly releases oxygen into the stored water in case of emergency. The emergency is a power outage. However, the emergency is not limited to this, and it may also be in case of a failure of the oxygen dissolving device 13 or a failure of the oxygen supply facility 29. The upstream part of the emergency line 32 is connected to the oxygen tank 35, and the downstream part is located inside the water tank 11. The oxygen tank 35 contains high-pressure oxygen or liquid oxygen. Further, an emergency on-off valve 36 is located on the emergency line 32. The emergency on-off valve 36 is a normally open valve that closes when energized. Therefore, during a power outage, the emergency on-off valve 36 opens, and the oxygen is conveyed from the oxygen tank 35 to the stored water through the emergency line 32 and released into the stored water. Note that the emergency on-off valve 36 does not have to be a normally open valve, and for example, it may be a control valve to which a driving power source is supplied in case of emergency.

[0019] The auxiliary line 31 has an auxiliary line nozzle 37 as an outlet. The emergency line 32 has an emergency line nozzle 38 as an outlet. The auxiliary line nozzle 37 and the emergency line nozzle 38 are arranged in the water tank 11 and release oxygen bubbles into the stored water. The auxiliary line nozzle 37 and the emergency line nozzle 38 are preferably arranged below the water tank 11. For example, the auxiliary line nozzle 37 and the emergency line nozzle 38 are arranged on the bottom surface of the water tank 11. Also, the auxiliary line nozzle 37 and the emergency line nozzle 38 may be arranged below the intermediate position between the bottom surface of the water tank 11 and the water surface of the water tank 11.

[0020] <Control device> The control device 15 is a device that controls each device included in the aquaculture facility 100. The control device 15 has a processor, a volatile memory, a non-volatile memory, an I / O interface, etc. In the non-volatile memory of the control device 15, a control program for the oxygen dissolution device 13 and a control program for the aeration device 14, as well as various data, are stored, and the processor performs arithmetic processing using the volatile memory based on each program.

[0021] The control device 15 is electrically connected to the dissolved oxygen concentration meter 12, and can acquire the dissolved oxygen concentration of the stored water based on the measurement signal received from the dissolved oxygen concentration meter 12. Further, the control device 15 is electrically connected to the oxygen flow rate adjustment valve 27 of the oxygen dissolution device 13 and the oxygen auxiliary valve 34 of the aeration device 14, and can control these valves 27, 34 by transmitting a control signal to these valves 27, 34. Note that the control device 15 may be divided into a plurality of control devices.

[0022] The functions of the elements disclosed in this specification can be executed using a circuit or processing circuit including a general-purpose processor, a dedicated processor, an integrated circuit, an ASIC (Application Specific Integrated Circuits), a conventional circuit, and / or a combination thereof, configured or programmed to execute the disclosed functions. Since the processor includes transistors and other circuits, it is regarded as a processing circuit or a circuit. In the present disclosure, a circuit, a unit, or a means is hardware that executes the listed functions, or hardware programmed to execute the listed functions. The hardware may be the hardware disclosed in this specification, or other known hardware programmed or configured to execute the listed functions. When the hardware is a processor considered to be a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used for the configuration of the hardware and / or the processor.

[0023] (Control Program of Oxygen Dissolving Device) Next, the control program of the oxygen dissolving device 13 will be described. FIG. 2 is a flowchart of the control program of the oxygen dissolving device 13. The control program of the oxygen dissolving device 13 is a program for controlling the oxygen flow rate adjustment valve 27 based on the target value of the dissolved oxygen concentration of the stored water. That is, it is a program for controlling the opening degree of the oxygen flow rate adjustment valve 27 so that the dissolved oxygen concentration of the stored water becomes the target value. The control program of the oxygen dissolving device 13 is executed by the control device 15.

[0024] When the control program of the oxygen dissolving device 13 is executed, first, the control device 15 acquires the dissolved oxygen concentration of the stored water (step S1). As described above, the control device 15 can acquire the dissolved oxygen concentration of the stored water by receiving a measurement signal from the dissolved oxygen concentration meter 12.

[0025] Subsequently, the control device 15 determines whether or not the dissolved oxygen concentration of the stored water acquired in step S1 is lower than a predetermined target value (step S2). The target value in this embodiment is the appropriate dissolved oxygen concentration of the stored water for aquaculture. The target value may be a fixed value or a variable value.

[0026] In step S2, when the control device 15 determines that the dissolved oxygen concentration of the stored water is lower than the target value (NO in step S2), it increases the opening degree of the oxygen flow rate adjustment valve 27 (step S3). As a result, the amount of oxygen contained in the supply water increases, and the dissolved oxygen concentration of the stored water rises. After passing through step S3, the control device 15 returns to step S1 and repeats each step.

[0027] On the other hand, in step S2, when the control device 15 determines that the dissolved oxygen concentration of the stored water is not lower than the target value (YES in step S2), it proceeds to step S4.

[0028] Subsequently, in step S4, the control device 15 determines whether or not the dissolved oxygen concentration of the stored water acquired in step S1 exceeds the aforementioned target concentration.

[0029] In step S4, when the control device 15 determines that the dissolved oxygen concentration of the stored water has exceeded the target value (NO in step S4), it reduces the opening degree of the oxygen flow rate adjustment valve 27 (step S5). As a result, the amount of oxygen contained in the supply water decreases, and the dissolved oxygen concentration of the stored water decreases. After passing through step S5, the control device 15 returns to step S1 and repeats each step.

[0030] On the other hand, in step S4, when the control device 15 determines that the dissolved oxygen concentration of the stored water does not exceed the target value (YES in step S4), it returns to step S1 and repeats each step.

[0031] According to the control program of the oxygen dissolution device 13 described above, the dissolved oxygen concentration of the stored water can be maintained near the target value. However, the dissolved oxygen concentration of the stored water may vary greatly depending on the activity status of the aquaculture target and external factors. In this case, there is a possibility that the dissolved oxygen concentration of the stored water cannot be maintained within a certain range only by the control of the oxygen dissolution device 13 described above. Therefore, in the present embodiment, the control program of the aeration device 14 described below is also implemented together.

[0032] (Control Program of Aeration Device) Next, the control program of the aeration device 14 will be described. FIG. 3 is a flowchart of the control program of the aeration device 14. The control program of the aeration device 14 is a program that supplementarily assists the dissolved oxygen concentration of the stored water, and is implemented in parallel with the control program of the oxygen dissolution device 13 described above. Further, the control program of the aeration device 14 is executed by the control device 15.

[0033] When the control program of the aeration device 14 is executed, first, the control device 15 acquires the dissolved oxygen concentration of the stored water (step S11). As described above, the control device 15 can acquire the dissolved oxygen concentration of the stored water by receiving a measurement signal from the dissolved oxygen concentration meter 12.

[0034] Subsequently, the control device 15 determines whether or not the dissolved oxygen concentration of the stored water acquired in step S11 is lower than a predetermined first threshold value (step S12). The first threshold value in the present embodiment is a value smaller than the target value used in the control program of the oxygen dissolution device 13, and is the minimum required dissolved oxygen concentration for aquaculture. The first threshold value may be a fixed value or a variable value that varies according to the variation of the target value.

[0035] In step S12, when the control device 15 determines that the dissolved oxygen concentration of the stored water is lower than the first threshold value (NO in step S12), it opens the oxygen auxiliary valve 34 (step S13). If the oxygen auxiliary valve 34 is already open, in step S13, the oxygen auxiliary valve 34 maintains the open state or increases the opening degree. As a result, oxygen is released into the stored water, and the dissolved oxygen concentration of the stored water increases. After passing through step S13, the control device 15 returns to step S11 and repeats each step.

[0036] On the other hand, in step S12, when the control device 15 determines that the dissolved oxygen concentration of the stored water is not lower than the first threshold value (YES in step S2), it proceeds to step S14.

[0037] Subsequently, in step S14, the control device 15 determines whether or not the dissolved oxygen concentration of the stored water acquired in step S11 is not higher than a second threshold value. The second threshold value in the present embodiment is a value larger than the target value used in the control program of the oxygen dissolution device 13. For example, the second threshold value is an excessive dissolved oxygen concentration for aquaculture. The second threshold value may be a fixed value or a variable value that varies according to the variation of the target value.

[0038] In step S14, when the control device 15 determines that the dissolved oxygen concentration of the stored water exceeds the second threshold value (NO in step S14), it closes the oxygen auxiliary valve 34 (step S15). If the oxygen auxiliary valve 34 is already closed, in step S15, the oxygen auxiliary valve 34 maintains the closed state or reduces the opening degree. As a result, the dissolved oxygen concentration of the stored water gradually decreases due to the activities of the aquaculture targets and the like. After passing through step S15, the control device 15 returns to step S11 and repeats each step.

[0039] On the other hand, in step S14, when the control device 15 determines that the dissolved oxygen concentration of the stored water does not exceed the second threshold value (YES in step S14), it returns to step S11 and repeats each step.

[0040] According to the control program of the aeration device 14 described above, even if the dissolved oxygen concentration of the stored water cannot be kept constant only by the oxygen dissolving device 13, at least the dissolved oxygen concentration of the stored water can be maintained at or above the first threshold value, that is, at or above the dissolved oxygen concentration that is minimally required for aquaculture. In addition, since the dissolved oxygen concentration of the stored water can be maintained below the second threshold value, it is possible to suppress the consumption due to excessive oxygen release into the stored water by the aeration device 14.

[0041] (Modification example) In the above embodiment, in order to maintain the dissolved oxygen concentration of the stored water at the target value, the amount of oxygen dissolved in the supply water is adjusted by controlling the oxygen dissolving device 13. However, in order to maintain the dissolved oxygen concentration of the stored water at the target value, the aeration device 14 may be controlled. For example, the amount of oxygen dissolved in the supply water by the oxygen dissolving device may be kept constant, and the amount of oxygen released from the aeration device 14 into the stored water may be adjusted to maintain the dissolved oxygen concentration of the stored water at the target value. Further, for example, the dissolved oxygen concentration of the stored water may be maintained at the target value by adjusting both the amount of oxygen dissolved in the supply water by the oxygen dissolving device and the amount of oxygen released from the aeration device 14 into the stored water.

[0042] (Summary) The first item disclosed in this specification is an aquaculture facility comprising a water tank for storing aquaculture water, an oxygen dissolution device for internally dissolving oxygen in the supply water supplied to the water tank, and an aeration device for releasing oxygen into the stored water stored in the water tank.

[0043] According to this configuration, since the aeration device is provided in addition to the oxygen dissolution device, it is possible to respond to changes in the dissolved oxygen concentration of the stored water stored in the water tank.

[0044] The second item disclosed in this specification is that the oxygen dissolution device adjusts the amount of oxygen dissolved in the supply water based on the target value of the dissolved oxygen concentration of the stored water, and the aeration device is configured such that when the dissolved oxygen concentration of the stored water falls below a first threshold value from the target value, the amount of oxygen released into the stored water is increased. This is the aquaculture facility according to the first item.

[0045] According to this configuration, even if the dissolved oxygen concentration of the stored water cannot be maintained at the target value by the oxygen dissolution device, the dissolved oxygen concentration of the stored water can be maintained higher than the first threshold value by the aeration device.

[0046] The third item disclosed in this specification is that the aeration device reduces the amount of oxygen released into the stored water when the dissolved oxygen concentration of the stored water exceeds a second threshold value higher than the target value. This is the aquaculture facility according to the first or second item.

[0047] According to this configuration, it is possible to suppress the consumption caused by excessive release of oxygen into the stored water by the aeration device.

[0048] The fourth item disclosed in this specification is that the aeration device includes an emergency line for releasing oxygen into the stored water during a power outage. This is the aquaculture facility according to any one of the first to third items.

[0049] According to this configuration, even when the power supply of the aquaculture facility is lost, it is possible to continue releasing oxygen into the stored water.

[0050] The fifth item disclosed in this specification is an aquaculture facility including a water tank for storing aquaculture water, an oxygen dissolution device for mechanically dissolving oxygen internally in the supply water supplied to the water tank, and an aeration device for releasing oxygen into the stored water stored in the water tank. Based on the target value of the dissolved oxygen concentration of the stored water, the amount of oxygen dissolved in the supply water by the oxygen dissolution device is adjusted, and when the dissolved oxygen concentration of the stored water falls below a first threshold lower than the target value, the amount of oxygen released from the aeration device into the stored water is increased. This is a method for adjusting the dissolved oxygen concentration.

[0051] According to this method, even if the dissolved oxygen concentration of the stored water cannot be maintained at the target value by the oxygen dissolution device, the dissolved oxygen concentration of the stored water can be maintained higher than the first threshold by the aeration device.

Explanation of Signs

[0052] 11 Water tank 12 Dissolved oxygen concentration meter 13 Oxygen dissolution device 14 Aeration device 15 Control device 21 Supply line 22 Drain outlet 23 Outlet 26 Oxygen dissolution device body 27 Oxygen flow rate adjustment valve 28 Oxygen supply line 29 Oxygen supply facility 31 Auxiliary line 32 Emergency line 33 Oxygen supply facility 34 Oxygen auxiliary valve 35 Oxygen tank 36 Emergency on-off valve 37 Auxiliary line nozzle 38 Emergency line nozzle 100 Aquaculture facility

Claims

1. A water tank for storing aquaculture water, An oxygen dissolution device for internally dissolving oxygen in the supply water supplied to the water tank, And an aeration device for releasing oxygen into the stored water stored in the water tank, an aquaculture facility equipped with the same.

2. The oxygen dissolution device adjusts the amount of oxygen dissolved in the supply water based on a target value of the dissolved oxygen concentration of the stored water, When the dissolved oxygen concentration of the stored water falls below a first threshold value lower than the target value, the aeration device increases the amount of oxygen released into the stored water. The aquaculture facility according to Claim 1.

3. When the dissolved oxygen concentration of the stored water exceeds a second threshold value higher than the target value, the aeration device reduces the amount of oxygen released into the stored water. The aquaculture facility according to Claim 2.

4. The aeration device includes an emergency line for releasing oxygen into the stored water during a power outage. The aquaculture facility according to Claim 1.

5. A water tank for storing aquaculture water, An oxygen dissolution device for internally dissolving oxygen in the supply water supplied to the water tank, In an aquaculture facility equipped with an aeration device for releasing oxygen into the stored water stored in the water tank, Based on the target value of the dissolved oxygen concentration of the stored water, while adjusting the amount of oxygen dissolved in the supply water by the oxygen dissolution device, when the dissolved oxygen concentration of the stored water falls below a first threshold value lower than the target value, the amount of oxygen released from the aeration device into the stored water is increased. A method for adjusting the dissolved oxygen concentration.

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