JP2005245326A - Closed circulating culture system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a closed circulating culture system enabling the pH control without adding an alkaline agent and performing disinfection and sterilization treatment. <P>SOLUTION: The closed circulating culture system performs the circulation and cleaning of seawater in a rearing water tank 1 between the rearing water tank 1 for fish and shellfish and a water-cleaning device 2 for cleaning the circulating water. An electrolyzing tank 3 for electrolyzing seawater is connected to the water-cleaning device 2. The electrolyzing tank 3 is divided with a partition membrane 4 to a cathode chamber 6 holding a cathode 5 and an anode chamber 8 holding an anode 7, an alkaline water is formed in the cathode chamber 6 and an acidic water is formed in the anode chamber 8. The alkaline water formed in the cathode chamber 6 is added to the rearing water tank 1 through an addition water channel 9. The pH of the seawater is adjusted by the addition of the alkaline water formed in the electrolyzing tank 3 to the rearing water tank 1 and the apparatus can be sterilized and disinfected by using the formed acidic water. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a closed circulation aquaculture system that circulates in a closed system while purifying seawater (including artificial seawater) on land to cultivate seafood in a breeding aquarium or temporarily cultivate it. Is.

  A closed-type aquaculture system for raising food or appreciating seafood at a land point remote from the sea surface has been studied. In this closed-circulation aquaculture system, it is necessary to perform the process of removing the excrement and residual food of the reared fishery products from the rearing aquarium without using dilution in the surrounding environment. For this purpose, a water purification device is connected to the breeding aquarium, and the seafood excrement and residual food in the seawater are removed and purified while circulating the seawater in the breeding aquarium with the water purification device. Has been done.

The purification device is formed from a physical filtration unit that removes solid matter in seawater, a biological filtration unit that nitrifies and removes ammonia, which is excrement of seafood, with microorganisms such as nitrifying bacteria, and the like. It is general (see, for example, Patent Document 1 and Patent Document 2).
JP 63-63325 A Japanese Patent Laid-Open No. 64-181939

  When the ammonia excreted from seafood is nitrified and removed by the water purification device as described above, nitric acid is generated by nitrification, and the pH of the water in the breeding aquarium falls to a range not suitable for the breeding of seafood. There is a fear. For this reason, in the thing of patent documents 1 and patent documents 2, the pH of seawater in a breeding aquarium is used for breeding fishery products by adding an alkaline agent such as sodium bicarbonate or sodium carbonate. It is necessary to adjust to an appropriate range.

  However, when pH adjustment is performed by adding an alkaline chemical in this way, there is a possibility that the fishery products may be adversely affected by the addition of the chemical, and there is a problem that running cost increases due to consumption of the chemical.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a closed-circulation aquaculture system that can adjust the pH without the need to add an alkaline agent and can also be sterilized and sterilized. It is what.

  The closed circulation type aquaculture system according to claim 1 of the present invention circulates while purifying the seawater in the breeding tank 1 between the breeding tank 1 for breeding seafood and the water purification device 2 for purifying the water. In the closed circulation aquaculture system, an electrolytic cell 3 for electrolyzing seawater is connected to the purification device 2, and a cathode chamber 6 and an anode 7 in which the cathode 5 is arranged by partitioning the inside of the electrolytic cell 3 with a diaphragm 4 are provided. An addition water channel 9 for forming the anode chamber 8 to be disposed, generating alkaline water in the cathode chamber 6, generating acidic water in the anode chamber 8, and adding the alkaline water generated in the cathode chamber 6 to the breeding aquarium 1. It is characterized by providing.

  According to this invention, seawater breeding seafood can be electrolyzed to generate alkaline water and acidic water in the electrolysis tank 3, and by adding the generated alkaline water to the breeding tank 1, The pH drop of the seawater in the water tank 1 can be suppressed, and the pH can be adjusted without the necessity of adding an alkaline chemical. Acidic water produced by electrolyzing seawater contains hypochlorous acid and has high disinfection and sterilization performance. It can be used for sterilization of seawater and other various disinfection and sterilization purposes. is there.

  The invention of claim 2 is the acid water storage tank according to claim 1, wherein the acid water generated in the anode chamber 8 is stored and the hypochlorous acid concentration is reduced to a predetermined concentration, and then added to the purifier 2. 10 is provided.

  According to this invention, hypochlorous acid contained in acidic water can be added to the purification device 2 after reducing its concentration to such an extent that it does not exhibit fish poisoning effects, without adversely affecting fish and shellfish, It can disinfect and sterilize seawater with acidic water.

  Moreover, the invention of claim 3 is the acid water use part 11 provided with means for using acid water for various uses between the anode chamber 8 of the electrolytic cell 3 and the acid water storage tank 10 in claim 1 or 2. It is characterized by being provided.

  According to the present invention, the acidic water generated in the electrolytic cell 3 can be used for disinfection and sterilization of instruments and the like, as well as disinfection and sterilization of workers' shoes, in addition to seawater disinfection and sterilization.

  The invention of claim 4 is the alkaline water according to any one of claims 1 to 3, wherein alkaline water is added to the breeding aquarium 1 from the cathode chamber 6 of the electrolytic cell 3 in accordance with the timing of feeding the seafood in the breeding aquarium 1. The addition control device 12 is provided in the addition water channel 9.

  According to the present invention, the pH of the seawater in the breeding aquarium 1 decreases after a predetermined time of feeding, but an effective pH adjustment is achieved by adding alkaline water in accordance with this pH decrease to increase the pH. Can be performed.

  Further, the invention of claim 5 is provided with a pH measuring device 13 for measuring the pH of seawater in the breeding aquarium 1 according to any one of claims 1 to 3, and electrolysis according to the pH measured by the pH measuring device 13. The addition water channel 9 is provided with an alkaline water addition controller 12 for adding alkaline water from the cathode chamber 6 of the tank 3 to the breeding water tank 1.

  According to this invention, it is possible to increase the pH by adding alkaline water in accordance with a decrease in the pH of the seawater in the breeding aquarium 1, so that effective pH adjustment can be performed, and the breeding aquarium 1 It is possible to maintain the pH of the seawater in a range suitable for the rearing of seafood.

  In addition, the invention of claim 6 is characterized in that in any one of claims 1 to 5, it comprises a flow rate control device 14 for controlling the flow rate of seawater supplied from the water purification device 1 to the electrolytic cell 3. It is.

  According to the present invention, by controlling the flow rate of the seawater supplied to the electrolytic cell 3, the concentration of hypochlorous acid in acidic water produced by the electrolysis of seawater can be adjusted, and the high level required for sterilization It is possible to generate acidic water having a concentration.

  According to a seventh aspect of the present invention, in the sixth aspect, the flow rate control device 14 is configured to individually control the flow rate of seawater passed through the cathode chamber 6 and the flow rate of seawater passed through the anode chamber 8. It is characterized by this.

  According to this invention, the flow rate of the seawater supplied to the cathode chamber 6 and the anode chamber 8 is individually controlled, and the alkaline concentration of the alkaline water generated in the cathode chamber 6 and the acidic water generated in the anode chamber 8 are the next. The zinc acid concentration can be adjusted individually.

  According to an eighth aspect of the present invention, in any one of the first to seventh aspects, the power supply device 16 for supplying power to the cathode 5 and the anode 7 of the electrolytic cell 3 is formed so that the power supply potential to the cathode 5 and the anode 7 can be switched. It is characterized by comprising.

  According to the present invention, the scales attached to the cathode 5 and the anode 7 can be peeled and removed by reversing the feeding potential to the cathode 5 and the anode 7, and the cleanup of the cathode 5 and the anode 7 can be removed. It can be done easily.

  According to the present invention, seawater breeding seafood can be electrolyzed to generate alkaline water and acidic water in the electrolytic tank 3, and by adding alkaline water to the breeding tank 1, PH can be adjusted without the necessity of adding an alkaline agent. Acidic water produced by electrolyzing seawater contains hypochlorous acid and has high disinfection and sterilization performance. It can be used for sterilization of seawater and other various disinfection and sterilization purposes. is there.

  Hereinafter, the best mode for carrying out the present invention will be described.

  FIG. 1 shows an example of an embodiment of the present invention, in which a water purification apparatus 2 is connected to a breeding aquarium 1 where fish and shellfish are bred by a circulation channel 20 composed of an outward path and a return path, The seawater in the breeding aquarium 1 is circulated between the water purification apparatus 2 and the like. The water purification device 2 includes a physical filtration unit (not shown) that removes solids in seawater by filtration and the like, and a biological filtration unit (not shown) that decomposes and removes ammonia and the like in seawater with microorganisms such as nitrifying bacteria. The seawater in the breeding aquarium 1 is circulated between the water purification apparatus 2 and the seawater in the breeding aquarium 1 is kept in a water quality suitable for breeding seafood and closed. The fishery can be raised in the circulation system.

  The electrolytic cell 3 is connected to the water purification device 2 via a water supply path 15. The electrolytic cell 3 is provided with a diaphragm 4 and partitioned into a cathode chamber 6 and an anode chamber 8. A cathode 5 is disposed in the cathode chamber 6, and an anode 7 is disposed in the anode chamber 8. The anode 7 is made to oppose through the diaphragm 4. The water supply channel 15 is branched and connected to the inlet side of the cathode chamber 6 and the anode chamber 8, respectively, the addition water channel 9 is provided on the outlet side of the cathode chamber 6, and the outlet water channel 21 is provided on the outlet side of the anode chamber 8. Connected. A control valve 31 formed by an electromagnetic valve or the like is connected to the water supply path 15 so that the supply of seawater from the water purification device 2 to the electrolytic cell 3 can be controlled.

  Here, as shown in FIG. 2, it is preferable to provide a plurality of diaphragms 4 in parallel in the electrolytic cell 3 so that a plurality of cathode chambers 6 and a plurality of anode chambers 8 are alternately formed. 6 and anode chamber 8 are provided with cathode 5 and anode 7, respectively. Although not shown, the cathode 5 and the anode 7 are connected to a power feeding device 16 so that a negative potential is applied to the cathode 5 and a positive potential is applied to the anode 7 by the power feeding device 16. .

  The addition water channel 9 is connected to the breeding water tank 1, and a control valve 23 formed by an electromagnetic valve or the like is connected to the addition water channel 9. The outlet water channel 21 is connected to the acidic water storage tank 10, and the acidic water storage tank 10 is connected to the water purification device 2 by an acidic water addition water channel 22.

  In the system formed as described above, the fish and shellfish are reared in the seawater in the breeding aquarium 1, and the seawater in the breeding aquarium 1 is circulated between the water purification device 2 and The seawater in the breeding aquarium 1 can be kept at a water quality suitable for breeding seafood. And a part of seawater in the water purification apparatus 2 is supplied to the electrolytic cell 3 through the water supply path 15, and is electrolyzed. Here, since seawater is electrolyzed between the cathode 5 and the anode 7 facing each other through the diaphragm 4, alkaline water is generated in the cathode chamber 6 by the same principle as the alkali ion water conditioner, and the anode chamber 8. Acidic water is produced. Here, for example, when a direct current is applied to the cathode 5 and the anode 7 under conditions of 3 to 3.5 V and 6 A, alkaline water having a pH of about 9.5 is generated in the cathode chamber 6 and acidic water having a pH of about 4 is generated in the anode chamber 8. In addition, the acidic water contains hypochlorous acid produced by the anodic reaction at a concentration of about 200 ppm.

  Since alkaline water is generated in the cathode chamber 6 by electrolyzing seawater between the cathode 5 and the anode 7 facing each other through the diaphragm 4 in this way, a breeding aquarium whose pH tends to decrease due to nitrification of ammonia By adding alkaline water through the addition water channel 9, the pH of the seawater in the breeding aquarium 1 can be raised and adjusted to a pH in a range suitable for fish and shellfish breeding. Therefore, it is not necessary to adjust the pH by adding an alkaline chemical, and the problem of adversely affecting fishery products by adding chemicals and the problem of high running costs due to the addition of chemicals are eliminated. In particular, since the alkaline water added to the breeding aquarium 1 is seawater itself, the components of the seawater in the breeding aquarium 1 are not changed, and there is no possibility of adversely affecting seafood.

The acidic water generated in the anode chamber 8 of the electrolytic cell 3 passes through the outlet water channel 21 and is sent to the acidic water storage tank 10. This acidic water obtained by electrolyzing seawater contains hypochlorous acid (ClO ⁻ ) and has a disinfection and sterilization action and a bleaching action. Hypochlorous acid has a high concentration of several hundred ppm. Therefore, if this acidic water is added to the water purification device 2 as it is, there is a possibility that the fish and shellfish may have a fish poisoning action due to the high concentration of hypochlorous acid. For this reason, the concentration of hypochlorous acid in acidic water is lowered in the acidic water storage tank 10. As shown in FIG. 3, an aeration unit 24 and a storage unit 25 are formed in the acidic water storage tank 10 in the flow direction of seawater, and an aeration pipe 27 connected to a blower 26 is provided at the bottom of the aeration unit 24. It is arranged. Then, air blown from the blower is ejected from the aeration pipe 27 into the aeration unit 24 to remove the chlorine by aeration of the acidic water (seawater) in the aeration unit 24, and the hypochlorous acid concentration in the acidic water is reduced. It can be lowered. When there is no time allowance, a neutralizing agent such as sodium thiosulfate may be added to the acidic water in the reservoir 25 to reduce the hypochlorous acid concentration. In this way, by adding acidic water in which the concentration of hypochlorous acid is reduced to 0.05 ppm or less without fish poisoning action from the reservoir 25 through the acidic water addition water channel 22 to the water purification device 2, Seawater can be sterilized and sterilized with hypochlorous acid contained in a low concentration, and seawater can be bleached and decolorized.

  As described above, the alkaline water generated in the cathode chamber 6 of the electrolytic cell 3 is returned and reused for pH adjustment, and the acidic water generated in the anode chamber 8 of the electrolytic cell 3 is used for disinfection and sterilization. The system is operated in a completely closed system without significantly reducing the amount of seawater in the system, and without having to replenish or replace the seawater over a long period of time. It will be possible. It is also possible to discharge part of the acidic water from the acidic water storage tank 10 through the discharge port 28. In this case, after reducing the concentration of hypochlorous acid in the acidic water to 0.5 ppm or less. It is desirable to discharge.

  In the embodiment of FIG. 1 described above, the acidic water use section 11 is provided in the middle of the outlet water channel 21 between the anode chamber 8 of the electrolytic cell 3 and the acidic water storage tank 10. The acidic water use unit 11 is formed as a washing tank for storing acidic water or a shower room for ejecting acidic water, for example. The acidic water is used to disinfect the sterilization of instruments and the sterilization of shoes of breeding workers. Can be performed. Thus, when using acidic water for various disinfection disinfection, it is preferable to dilute so that the density | concentration of hypochlorous acid may be set to about 50-60 ppm. The acidic water used for disinfection and sterilization in the acidic water using unit 11 is sent to the acidic water storage tank 10 through the outlet water channel 21 in the same manner as described above.

  Here, when adjusting the pH by adding the alkaline water generated in the cathode chamber 6 of the electrolytic cell 3 to the breeding water tank 1 as described above, the pH adjustment is unnecessary when the pH of the seawater in the breeding water tank 1 is low. Therefore, it is desirable to add alkaline water only when the pH of the seawater in the breeding aquarium 1 rises. For example, when feeding into the breeding aquarium 1 and feeding, the excretion of the breeding fish and shellfish becomes active after a predetermined time from feeding, and the ammonia nitrification reaction in the water purification device 2 becomes popular, and the breeding tank 1 The pH of seawater increases. Therefore, if alkaline water is added to the breeding aquarium 1 at a predetermined time after feeding, effective pH adjustment can be performed. Thus, in order to add alkaline water to the breeding aquarium 1 in accordance with the timing of feeding the fish and shellfish in the breeding aquarium 1, the control valve 23 provided in the addition water channel 9 and the control for opening / closing the control valve 23 are controlled. It can be performed by forming the alkaline water addition control device 12 with the unit 30 and controlling the control valve 30 to open the control valve 23 for a predetermined time after a predetermined time of feeding. Since feeding is performed at a fixed time, by programming the control unit 30 so that the control valve 23 is opened at a timing that matches the feeding time, alkaline water is automatically added to the breeding aquarium 1. The pH can be adjusted by adding from the water channel 9.

  4 (a) and 4 (b) are time charts showing the timing of feeding and addition of alkaline water, in which alkaline water addition is ON and stop of alkaline water addition is OFF. FIG. 4 (a) is a time chart showing the timing of feeding and alkaline water addition when raising shrimp as seafood, and the controller 30 adds alkaline water for 1 hour one hour after the feeding time. By controlling the control valve 23, the pH of the seawater in the breeding aquarium 1 can be adjusted effectively. FIG. 4B is a time chart showing the timing of feeding and adding alkaline water when raising fish as seafood. The controller 30 adds alkaline water for 3 hours 5 hours after the feeding time. By controlling the control valve 23, the pH of the seawater in the breeding aquarium 1 can be adjusted effectively. In this way, adding alkaline water from the electrolytic cell 3 to the breeding tank 1 may be 1 hour every 3 hours when breeding shrimp and 3 hours every 7 hours when breeding fish. When a plurality of breeding aquariums 1 are installed to breed fishery products, the plurality of breeding aquariums 1 share one electrolytic cell 3 by shifting the time for adding alkaline water to each breeding aquarium 1. Can be achieved, and the equipment cost can be reduced.

  Moreover, by adding alkaline water from the electrolytic cell 3 according to the fluctuation of the pH of the seawater in the breeding aquarium 1, the pH can be adjusted to a predetermined fixed range, and the breeding aquarium 1 is suitable for seafood. It can be maintained in a pH environment. That is, as shown in FIG. 1, a pH measuring device 13 is provided in the breeding water tank 1, and the pH measuring device 13 is electrically connected to the control unit 30 of the alkaline water addition control device 12. When the pH of the seawater in the breeding aquarium 1 measured by the pH measuring device 13 is lower than a predetermined value, the control valve 23 is opened, and when the pH of the seawater in the breeding aquarium 1 is higher than a predetermined value, the control valve 23 is opened. The control unit 30 is programmed so as to be closed. Therefore, it is possible to perform control of adding alkaline water from the electrolytic cell 3 to the breeding water tank 1 through the addition water channel 9 or stopping the addition according to the pH of seawater in the breeding water tank 1. The pH of seawater can be adjusted to a predetermined fixed range.

  When acidic water generated in the anode chamber 8 by electrolyzing seawater in the electrolytic cell 3 as described above is used as sterilizing water, the acidic water is highly concentrated so as to contain high concentration of hypochlorous acid. May need to be generated. Therefore, as shown in FIG. 1, the flow control device 14 includes a control valve 31 provided in the water supply path 15 for supplying seawater from the water purification device 2 to the electrolytic cell 3 and a control unit 32 that controls the opening amount of the control valve 23. And the concentration of acidic water generated in the anode chamber 8 of the electrolytic cell 3 can be controlled by controlling the flow rate per hour of the seawater supplied from the water purification device 2 to the electrolytic cell 3. It is. That is, by reducing the flow rate of seawater supplied from the water purification device 2 to the electrolytic cell 3, the electrolytic density for seawater per unit amount can be increased, and high-concentration acidic water can be generated. is there.

  In the embodiment shown in FIG. 2, a plurality of cathode chambers 6 and anode chambers 8 are alternately formed in the electrolytic cell 3, and the water supply channel 15 is branched and connected to all of the cathode chamber 6 and the anode chamber 8. The flow rate of seawater passing through the cathode chamber 6 and the flow rate of seawater passing through the anode chamber 8 are simultaneously controlled by the flow rate control device 14.

  On the other hand, in the embodiment of FIG. 5 (a), the water supply channel 15 is first branched into two systems of a cathode chamber channel 34 and an anode chamber channel 35, and the cathode channel 34 is further branched to each cathode. An anode chamber channel 35 is further branched into the chamber 6 and connected to each anode chamber 8. As the control valve 31, a cathode control valve 36 is connected to the cathode channel 34. 35 are respectively provided with anode control valves 37. The control unit 32 is electrically connected to the cathode control valve 36 and the anode control valve 37 to form the flow rate control device 14, and the cathode control valve 36 and the anode control valve 37 are individually connected by the control unit 32. It can be controlled. When high-concentration acidic water needs to be generated, the anode control valve 37 is controlled so that the opening amount of the anode control valve 37 is reduced, and the flow rate of seawater supplied to the anode chamber 8 is reduced. As a result, the amount of seawater is reduced with respect to the amount of hypochlorous acid generated in the anode chamber 8, so that the concentration of acidic water generated in the anode chamber 8 can be increased. At this time, if the opening amount of the cathode control valve 36 is not changed, the concentration of alkaline water generated in the cathode chamber 6 is increased even if the concentration of acidic water generated in the anode chamber 8 is increased. Can be kept constant. Conversely, the amount of seawater is changed relative to the amount of alkali generated in the cathode chamber 6 by controlling the flow rate of seawater supplied to the cathode chamber 6 by controlling the opening amount of the cathode control valve 36. Therefore, the concentration of alkaline water generated in the cathode chamber 6 can be changed, and the concentrations of alkaline water generated in the cathode chamber 6 and acidic water generated in the anode chamber 8 are individually adjusted. Is something that can be done.

  In the embodiment of FIG. 5B, the cathode control valve 36 is provided in the addition water passage 9 that is collectively connected to the outlet of each cathode chamber 6, and the outlet water passage that is collectively connected to each anode chamber 8. 21 is provided with an anode control valve 37, and a control unit 32 is electrically connected to the cathode control valve 36 and the anode control valve 37 to form the flow rate control device 14. 36 and the anode control valve 37 can be individually controlled. Also in this embodiment, the amount of water coming out of the cathode chamber 6 and the amount of water coming out of the anode chamber 8 are adjusted by individually controlling the opening amounts of the cathode control valve 36 and the anode control valve 37, and the cathode chamber 6. The flow rate of the seawater that passes through the cathode chamber 8 and the flow rate of the seawater that passes through the cathode chamber 8 can be individually adjusted, and the alkaline water generated in the cathode chamber 6 and the anode chamber 8 are generated in the same manner as described above. The concentration of acidic water can be adjusted individually. Although not shown in FIGS. 5A and 5B, a negative potential is applied to the cathode 5 and a positive potential is applied to the anode 7 by the power feeding device 16.

  Moreover, seawater can be electrolyzed in the electrolytic cell 3 by applying a negative potential to the cathode 5 and applying a positive potential to the anode 7 by the power supply device 16 as described above, but the scale is formed on the surface of the cathode 5. And the like deposits and adheres, the electrical resistance of the surface of the cathode 5 increases and the efficiency of electrolysis decreases. Therefore, the feeding potential to the cathode 5 and the anode 7 by the feeding device 16 can be switched every predetermined time. By reversing the feeding potential to the cathode 5 and the anode 7 in this way and applying a positive potential to the cathode 5 and a negative potential to the anode 7, deposits such as scales can be peeled off from the surface of the cathode 5. And the efficiency of electrolysis can be kept high.

  When switching the power supply potential to the cathode 5 and the anode 7 as described above, for example, the power supply potential to the cathode 5 and the anode 7 can be reversed every week to perform the operation. In this case, in response to the reversal of the feeding potential to the cathode 5 and the anode 7, water path switching means such as a three-way valve (not shown) that switches between the addition water path 9 and the outlet water path 21 is provided, and the generated acidic water is acidic. It is necessary to add the alkaline water generated and supplied to the water use unit 11 to the breeding aquarium 1. Thus, by reversing the feeding potential to the cathode 5 and the anode 7 every predetermined period, the electrode can be used for a long period of time.

It is the schematic which shows an example of embodiment of this invention. It is a schematic sectional drawing which shows an electrolytic cell same as the above. It is a schematic sectional drawing of an acidic water storage tank same as the above. (A), (b) is a time chart of the timing of feeding and alkaline water addition, respectively. The other embodiment of this invention is shown, (a), (b) is a schematic sectional drawing of an electrolytic cell, respectively.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Breeding tank 2 Water purification apparatus 3 Electrolytic tank 4 Diaphragm 5 Cathode 6 Cathode chamber 7 Anode 8 Anode chamber 9 Addition water channel 10 Acidic water storage tank 11 Acidic water use part 12 Alkaline water addition control device 13 pH measurement device 14 Flow control device 15 Water supply channel 16 Power supply device

Claims (8)

  Purifies the electrolyzer that electrolyzes seawater in a closed-circulation aquaculture system that circulates the seawater in the breeding tank while purifying the seawater between the breeding tank that raises seafood and the water purification device that purifies the water. A cathode chamber in which the cathode is arranged and an anode chamber in which the anode is arranged are formed by partitioning the inside of the electrolytic cell with a diaphragm, and alkaline water is generated in the cathode chamber, and acidic water is produced in the anode chamber. A closed-circulation aquaculture system comprising an addition water channel for generating and adding alkaline water generated in a cathode chamber to a breeding aquarium.   The acidic water storage tank added to a purification apparatus after storing acidic water produced | generated in an anode chamber and reducing hypochlorous acid concentration to a predetermined density | concentration is provided. Closed circulation aquaculture system.   The closed circulation type according to claim 1 or 2, wherein an acidic water use section having means for using acidic water for various purposes is provided between the anode chamber of the electrolytic cell and the acidic water storage tank. Aquaculture system.   4. The addition water channel is provided with an alkaline water addition control device for adding alkaline water to the breeding aquarium from the cathode chamber of the electrolytic cell in accordance with the timing of feeding the seafood in the breeding aquarium. A closed-circulation aquaculture system according to crab.   A pH measuring device for measuring the pH of the seawater in the breeding aquarium is provided, and an alkaline water addition controller for adding alkaline water from the cathode chamber of the electrolytic cell to the breeding aquarium according to the pH measured by the pH measuring device is added to the water channel The closed circulation culture system according to any one of claims 1 to 3, wherein the closed circulation culture system is provided.   The closed circulation culture system according to any one of claims 1 to 5, further comprising a flow rate control device for controlling a flow rate of seawater passed through the electrolytic cell.   7. The closed circulation culture system according to claim 6, wherein the flow rate control device is configured to individually control the flow rate of seawater passed through the cathode chamber and the flow rate of seawater passed through the anode chamber. . The closed circulation type aquaculture system according to any one of claims 1 to 7, wherein a power feeding device for feeding power to the cathode and the anode of the electrolytic cell is formed so that the feeding potential to the cathode and the anode can be switched.

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