JP2016106534A - Fish and shellfish aquaculture water purification device, fish and shellfish aquaculture device, and fish and shellfish aquaculture water purification method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fish and shellfish aquaculture water purification device that can easily obtain clean water from the water to be purified containing solid organic matter and ammonium ion, a fish and shellfish aquaculture device having this fish and shellfish aquaculture water purification device and capable of easily culturing the fish and shellfish, and a fish and shellfish aquaculture water purification method capable of easily culturing the fish and shellfish.SOLUTION: A fish and shellfish aquaculture water purification device is provided for purifying the water to be purified. The fish and shellfish aquaculture water purification device can generate gaseous microbubbles containing ozone in the water to be purified in a septic tank, and can remove solid organic matter and ammonium ion in the water to be purified.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a fish and shellfish culture water purification device, a fish and shellfish culture device, and a method for purifying fish and shellfish culture water, and more particularly, to easily obtain clean water from purified water containing solid organic matter and ammonium ions. Fish and shellfish culture water purification device, fish shell culture device that has this fish and shellfish culture water purification device and can easily cultivate fish and shellfish, and fish and shellfish culture water that can easily cultivate fish and shellfish It relates to a purification method.

  Fish, shellfish, aquatic plants and the like (hereinafter sometimes referred to as “fishshells”) may be cultivated in a breeding aquarium. Dirt gradually accumulates in the water in the breeding aquarium due to food left over from the fish and shellfish, excrement of fish and shellfish, and dead bodies such as fish and shellfish. If the degree of water contamination in the rearing tank is large, the health of fish and shellfish will be impaired. Therefore, it is necessary to purify the accumulated water in the breeding water tank into clean water suitable for breeding fish and shellfish by using various purification devices.

  In the breeding aquarium, in particular, accumulation of solid organic matter suspended without dissolving in water and accumulation of ammonium ions dissolved in water become problems. Solid organic matter decays in water to reduce dissolved oxygen in water, attaches to fish gills, kills fish by suffocation, interferes with light transmission in water, and impairs plant photosynthesis Sometimes. In addition, ammonium ions dissolved in water may harm the health of fish and shellfish in water. A technique for obtaining clean water by decomposing solid organic substances or ammonium ions in water is already known.

  For example, in Patent Document 1, “In order to generate a large bubble by pulverizing and activating a bubble by releasing it from pressure under pressure, while supplying a large amount of bubbles necessary for adsorption of the suspension, Bubbles tend to adsorb the suspension, and the foam that has adsorbed the suspension stays for a while, so the contact time with the suspension of the foam becomes longer, and the bubbles tend to aggregate and concentrate. It is easy to grow into a stable foam and is discharged out of the tank in a state in which the stable foam is formed, so that it is possible to remarkably enhance the ability to remove suspensions ”(Patent Document 1) Paragraph number 0024 column). However, Patent Document 1 neither describes nor suggests that ammonium ions dissolved in water are removed.

  Further, in Patent Document 2, “characterized in that microbubbles are brought into contact with microorganisms living in natural water areas to increase and activate the growth rate of microorganisms, thereby nitrifying or nitrating ammoniacal nitrogen. A method for purifying natural water is disclosed (see claim 2 of Patent Document 2). However, Patent Document 2 neither describes nor suggests that solid organic substances suspended in water are removed.

  Conventionally, in order to remove solid organic matter suspended in water and decompose ammonium ions dissolved in water, an apparatus capable of removing solid organic matter as disclosed in Patent Literature 1 and Patent Literature 2 It is necessary to use in combination with an apparatus capable of decomposing ammonium ions as disclosed. However, there is a problem that operation and control of the apparatus become complicated by using a plurality of apparatuses.

Patent No. 5130428 JP 2006-272307 A

  The problem to be solved by the present invention includes a fish and shellfish culture water purification device capable of easily obtaining clean water from purified water containing solid organic matter and ammonium ions, and this fish and shellfish culture water purification device, It is an object of the present invention to provide a fish and shellfish culture device that can easily cultivate fish and shellfish, and a method for purifying fish and shellfish culture water that can easily cultivate fish and shellfish.

Means for solving the problems are as follows:
(1) A fish and shellfish culture water purification device for purifying purified water, which generates microbubbles of gas containing ozone in the purified water in the septic tank to remove solid organic matter and ammonium ions in the purified water Fish shellfish culture water purification device,
(2) The fish shellfish culture water purification device according to (1), wherein the gas is a gas obtained by changing oxygen in the atmosphere to ozone.
(3) The fish shellfish culture water purification device according to (1) or (2), wherein the gas is pressed into a microbubble generator that generates microbubbles,
(4) A foam separation device and an ozone gas generation device, the foam separation device comprising: the septic tank; a water supply pipe arranged to be able to supply the purified water to the septic tank; A water feed pump that pumps the water to be purified provided in a part of the water pipe, a gas injection pipe that is capable of press-fitting the gas into the water to be purified, and a gas injection pipe that is pressed into the water to be purified from the gas injection pipe Any one of the above (1) to (3), characterized in that the ozone generating device is connected to the gas injection pipe. Fish and shellfish culture water purification device according to
(5) Any one of (1) to (4), wherein the rearing water tank containing the water to be purified and the water to be purified in the rearing water tank are provided so as to be supplied to the water purification tank. A fish and shellfish culture water purification device according to claim 1, and a fish and shellfish culture device,
(6) The downstream of the fish and shellfish culture water purification apparatus is provided with a post-treatment tank to which purified water purified by the fish and shellfish culture water purification apparatus is sent (5) ) Fish and shellfish farming device,
(7) A method for purifying fish and shellfish aquaculture water by generating microbubbles of gas containing ozone in the water to be purified in the breeding aquarium, and removing solid organic matter and ammonium ions in the water to be purified.
(8) The step of supplying the purified water in the breeding aquarium to the septic tank, the step of generating microbubbles of gas containing ozone in the purified water in the septic tank, and the microbubbles floating in the septic tank A step of separating the foam by discharging the microbubbles floating near the water surface to the outside of the septic tank, a step of feeding the water after the foam separation to a breeding tank or a post-treatment tank, The method for purifying fish and shellfish aquaculture water as set forth in (7) above,
(9) The method according to (7) or (8), wherein the gas is a gas obtained by changing oxygen in the atmosphere to ozone.

  According to the fish shellfish culture water purification apparatus according to the present invention, it is possible to reduce both solid organic matter and ammonium ions present in the to-be-purified water, and it is possible to easily obtain clean water.

FIG. 1 is a schematic diagram illustrating an example of a fish and shellfish culture water purification apparatus. FIG. 2 is a schematic diagram illustrating another example of the fish shellfish culture water purification device. FIG. 3 is a schematic diagram illustrating an example of a fish shellfish culture apparatus. FIG. 4 is a graph showing the relationship between the elapsed time after the generation of microbubbles in Example and the ammonia nitrogen removed together with foam separation.

  The fish and shellfish culture water purification apparatus according to the present invention has a septic tank, and microbubbles of a gas containing ozone in the septic water in the septic tank (hereinafter sometimes simply referred to as “ozone gas”) are generated. .

  The septic tank should just be a water tank which can accommodate to-be-purified water inside. Moreover, the septic tank should just be a magnitude | size which can remove a solid organic substance and ammonium ion by generating a microbubble. The shape of the septic tank is not particularly limited, and may be a cylindrical shape, a prismatic shape, a truncated cone shape, a truncated pyramid shape, or the like.

  The water to be purified in the septic tank contains solid organic matter and ammonium ions. The solid organic material may be an organic material suspended without being dissolved in water, and the type of the solid organic material is not particularly limited. The solid organic matter is an organic matter that is usually released in fish and shellfish aquaculture activities. Specific examples of the solid organic matter include fish excrement, food leftovers, aquatic debris, and the like. The size of the solid organic material is not particularly limited as long as it can float to the vicinity of the water surface by the buoyancy of microbubbles described later.

  The purified water may be fresh water or seawater. It is preferable that the water to be purified is salt water containing sodium chloride of about 0.5% by mass or more and 5% by mass or less. When the water to be purified contains sodium chloride within the above numerical range, fine microbubbles are likely to be generated in the water to be purified.

  The microbubble is a fine bubble generated in the water to be purified, and the bubble diameter is usually 100 μm or less. As for the size of the microbubbles, the average bubble diameter is more preferably 1 μm or more and 50 μm or less. When the size of the microbubbles is within the above numerical range, the generation of radicals due to the disappearance of microbubbles, which will be described later, and the formation of stable bubbles due to the joining of the microbubbles occur in a balanced manner. The size of the microbubble is measured by, for example, a light blocking method using a liquid particle counter. The average of the bubble diameters can be obtained, for example, by averaging the bubble diameters of 100 or more microbubbles.

  Microbubbles have a lower rising speed than normal bubbles, and disappear when the internal gas dissolves in water. Free radicals are generated as microbubbles disappear. As will be described later, in the present invention, free radicals generated when the microbubbles disappear are reacted with the solid organic matter to generate a large amount of hydroxyl groups on the surface of the solid organic matter. Moreover, a part of microbubble forms stable foam, without annihilating in water. The stable foam is formed by joining a plurality of microbubbles. The stable foam slowly rises in water and can reach the vicinity of the water surface.

  The amount of microbubbles generated in the water to be purified is not particularly limited. If the amount of microbubbles is small, solid organic matter and dissolved ammonia may not be sufficiently removed by the microbubbles. As long as the effects of the present invention are exhibited, the amount of microbubbles generated in the water to be purified can be appropriately adjusted.

  The method for generating microbubbles in the water to be purified is not particularly limited. For example, a turbulent flow method in which microbubbles are generated by shearing bubbles in turbulent flow, a large amount of gas is dissolved in the water to be purified under high pressure. The pressure and pressure reduction method that generates microbubbles by reducing the pressure after that, and the generation of microbubbles by creating a high-speed vortex in the water to be purified, blowing gas into the vortex, and cutting and crushing the bubbles in the vortex Microbubbles can be generated by a liquid shear method or the like.

  The gas contained in the microbubbles may contain a gas other than ozone as long as the effects of the present invention are exhibited. For example, the gas contained in the microbubbles may contain nitrogen, oxygen, argon, carbon dioxide, or the like as necessary.

  Next, an example of a reaction mechanism in which solid organic matter and ammonium ions are removed by microbubbles in the water to be purified will be described.

  In the water to be purified, the gas in the microbubbles gradually dissolves into the water to be purified. As a result, the microbubbles shrink and eventually disappear. When the microbubbles disappear in water, free radicals such as hydroxyl radicals are generated from the surface of the microbubbles. Furthermore, ozone contained in the gas released into water when the microbubbles disappear, reacts with water to generate hydroxyl radicals. Therefore, the gas microbubbles containing ozone in the present invention can generate a large amount of hydroxyl radicals by disappearing in water. The hydroxyl radical is sometimes referred to as a hydroxy radical, and may be represented by the formula of .OH.

When the hydroxyl radical reacts with the solid organic substance in the water to be purified, the solid organic substance is not completely decomposed, and many hydrophilic hydroxyl groups are formed on the surface of the solid organic substance. In the water to be purified, ammonium ions (NH ⁴⁺ ) that are cations adsorb to hydroxyl groups formed on the surface of the solid organic matter. When ammonium ions are adsorbed on all hydroxyl groups formed on the surface of the solid organic material, the surface of the solid organic material becomes hydrophobic. The solid organic substance having a hydrophobic surface is easily adsorbed on the surface of the stable foam formed by joining the microbubbles, and floats in the water together with the stable foam. By removing the stable foam that has floated to the vicinity of the water surface from the water, the solid organic matter adhering to the surface of the microbubbles and the ammonium ions adsorbing to the surface of the solid organic matter can be simultaneously removed from the water to be purified. In the purified water obtained after the removal of the stable foam, solid organic matter and ammonium ions may remain, but the content of the solid organic matter and the ammonium ion concentration in the purified water before the removal of the stable foam. In comparison, both the solid organic matter content and the ammonium ion concentration in the purified water after the removal of the stable foam are greatly reduced.

The gas in the microbubbles is preferably a gas obtained by changing oxygen in the atmosphere to ozone. The atmosphere contains about 20% oxygen O ₂ by volume. By performing discharge treatment or ultraviolet irradiation on the atmosphere, a gas in which part or all of oxygen O _{2 in} the atmosphere has been changed to ozone O ₃ can be obtained. As the gas in the microbubble, a gas in which all of oxygen contained in the atmosphere is changed to ozone may be used, or a gas in which a part of oxygen in the atmosphere is changed to ozone may be used. . In order to prevent the concentration of ozone contained in the gas from becoming too high, it is preferable to use a gas in which part of oxygen in the atmosphere is changed to ozone.

  The microbubbles in the water to be purified are preferably generated by a microbubble generator. The microbubble generator may be any device having a function of taking in gas containing ozone from the outside, releasing the gas into water, and generating microbubbles of the gas in water. When the microbubble generator takes in the gas containing ozone, microbubbles of gas containing ozone are generated in the water to be purified.

  The gas is preferably pressed into a microbubble generator that generates microbubbles. By injecting the gas, more microbubbles can be generated in the water to be purified. The pressure when injecting gas into the microbubble generator is not particularly limited. In order to press-fit the gas, for example, the inside of the pipe connected to the microbubble generator may be pressurized using a pump or the like.

  A conventionally well-known apparatus can be used as a microbubble generator. An example of a microbubble generator is a microbubble generating nozzle that can generate microbubbles from a discharge outlet by a turbulent flow method. An example in which a commercially available microbubble generating nozzle is used as the microbubble generator is shown in FIG.

  In FIG. 1, purified water 3 is sent to a septic tank 4 through a water pipe 2. By providing the water pressure feed pump 16 in a part of the water feed pipe 2, the purified water can be fed from the upstream side of the water feed pipe 2 to the septic tank 4. The to-be-purified water 3 accommodated in the septic tank 4 is taken into the submersible pump 5 from the intake port 6 of the submersible pump 5 provided at the bottom of the septic tank 4. The to-be-purified water 3 taken into the submersible pump 5 is returned to the septic tank 4 through the discharge port 7 in the submersible pump 5. A microbubble generating nozzle 8 is connected to the discharge port 7. An air suction pipe 9 in the microbubble generation nozzle 8 is connected to an ozone gas generation device 11 through a tube 10. The ozone gas generated by the ozone gas generator 11 is taken into the microbubble generating nozzle 8 from the air suction pipe 9 through the tube 10. In FIG. 1, the tube 10 that connects the ozone gas generator 11 and the microbubble generating nozzle 8 functions as a gas injection tube that injects ozone gas into the water to be purified in the submersible pump 5. In the microbubble generating nozzle 8, the water to be purified and ozone gas are mixed to form a turbulent flow, thereby generating microbubbles of ozone gas in the water to be purified. Thereafter, water to be purified containing microbubbles of ozone gas is discharged from the outlet of the microbubble generating nozzle 8 to the septic tank 4. In order to press-fit the ozone gas generated in the ozone gas generator 11 into the water to be purified, the ozone gas generator 11 may have a gas press-fitting function. The member may be provided in a part of the tube 10. In the example in FIG. 1, a foam separation device is formed by the septic tank 4, the water supply pipe 2, the water pressure feed pump 16, the tube 10, and the microbubble generating nozzle 8.

  As another example of the microbubble generator, there is a microbubble generator that can generate microbubbles by a pressure reduction method. As an example of the microbubble generator, FIG. 2 shows an example in which a microbubble generator using a pressure reduction method is used.

  In FIG. 2, the water to be purified 23 is sent to the septic tank 24 through the water pipe 22. By providing the water pressure feed pump 17 in a part of the water feed pipe 22, the purified water can be sent from the upstream side of the water feed pipe 22 to the septic tank 24. The to-be-purified water 23 stored in the septic tank 24 is pumped to the outside of the clarified water tank 24 through a pipe 20 from a water intake 26 provided in the water. The pipe 20 has a water intake port 26 at one end provided in the septic tank 24, and has a discharge port 27 at the other end provided in the septic tank 24. The pump 30 and the gas dissolution tank 19 are connected in this order from the upstream side. In the pipe 20, a branch portion is provided between the water intake 26 and the pump 30, and a gas injection pipe 28 extends from the branch portion. An ozone generator 29 is provided at the end of the gas injection pipe 28 opposite to the branching portion. Ozone gas generated in the ozone gas generator 29 is blown into the to-be-purified water 23 drawn up from the water intake 26 at the branching portion where the gas injection pipe 28 branches. Then, the to-be-purified water in which ozone gas was blown in is sent to the gas dissolution tank 19 maintained at a high pressure by the pump 30. In the gas dissolution tank 19, the ozone gas exceeds the saturation amount under constant pressure conditions and dissolves in the water to be purified. Thereafter, the water to be purified 23 is sent to the discharge port 27. At the discharge port 27 under atmospheric pressure conditions, ozone gas that has been supersaturated in the water to be purified in the pipe 20 is released into the water as microbubbles. Thereby, the to-be-purified water containing microbubbles is discharged from the discharge port 27 into the septic tank 24. In order to press-fit the ozone gas generated in the ozone gas generating device 29 into the water to be purified, the ozone gas generating device 29 may have a gas press-fitting function. The member may be provided in a part of the gas injection pipe 28. In the example in FIG. 2, a microbubble generator using a pressure reduction method is formed by the intake port 26, the pipe 20, the pump 30, the gas dissolution tank 19, and the discharge port 27. Moreover, in the example in FIG. 2, a foam separation apparatus is formed by the septic tank 24, the water supply pipe 22, the water pressure feed pump 17, the gas pressure injection pipe 28, and the microbubble generator.

  Next, the fish and shellfish culture apparatus according to the present invention will be described.

  As shown in FIG. 3, the fish and shellfish culture device 31 according to the present invention includes a breeding water tank 32 and the fish and shellfish culture water purification device 33. In the breeding aquarium 32, organisms such as fish, shellfish, and aquatic plants are bred. The breeding water in the breeding aquarium accumulates dirt due to food leftovers and dead creatures. The breeding water in which dirt accumulates contains a large amount of solid organic matter suspended in water and dissolved ammonium ions. Such breeding water in which dirt accumulates adversely affects the growth of fish and the like in the breeding water, and thus is treated water to be purified. As shown in (1) of FIG. 3, the to-be-purified water in the breeding aquarium 32 can be supplied to the septic tank in the fish shell culture water purification apparatus 33. Specifically, as in the example shown in FIGS. 1 and 2, when the fish and shellfish culture water purification apparatus has a water pipe, the upstream end of the water pipe may be connected to the breeding aquarium 32. Thereby, the to-be-purified water in the breeding water tank 32 is supplied to the septic tank through the water pipe. The amount of water to be purified supplied to the septic tank may be adjusted according to the processing capacity of the septic tank.

  Purified water is obtained by purifying the water to be purified in the fish shellfish culture water purification device 33. Specifically, in the septic tank of the fish and shellfish culture water purification device 33, purified gas is obtained by generating microbubbles of gas containing ozone in the water to be purified and removing the stable foam floating near the water surface. It is done. As shown in (4) of FIG. 3, solid organic matter and ammonium ions are discharged from the water to be purified together with the stable bubbles of microbubbles removed from the septic tank. Therefore, the purified water after being purified by the fish and shellfish culture water purification device 33 has a lower amount of solid organic matter suspended in water and a concentration of ammonium ions dissolved in water than the purified water before purification. In addition, as shown by (2) in FIG. 3, ozone gas may be injected into the water to be purified by the ozone gas generator 34 in order to generate the microbubbles of the gas containing ozone.

  The purified water obtained in the fish and shellfish culture device 33 may be returned directly to the breeding aquarium 32 or may be sent to the rear treatment tank 35 and then returned to the breeding aquarium 32. The post-stage treatment tank 35 has a function of further purifying the purified water so that the water quality is more suitable for the growth of fish and shellfish in the breeding water tank 32. In the example in FIG. 3, as shown in (3), the purified water obtained by the fish and shellfish culture water purification device 33 is sent to the subsequent septic tank 35.

  A biological treatment tank is mentioned as an example of a post-stage septic tank. In the biological treatment tank, floating microorganisms exist, and the water in the tank is blown away, so that the solid organic matter remaining in the purified water is decomposed by the oxidation reaction of the microorganisms. Another example of the latter-stage septic tank is a filtration tank that physically filters fine substances floating in the purified water using a membrane, a mesh, or the like. In addition, only one post-stage septic tank may be provided, or a plurality of post-stage septic tanks may be provided.

  When the fish and shellfish culture device according to the present invention is used, purified water from which solid organic matter and ammonium ions have been removed can be obtained by operating only the fish and shellfish culture water purification device. In the fish and shellfish culture device according to the present invention, it is not necessary to use two devices, namely, a solid organic matter separation device and an ammonium ion separation device. Therefore, purified water suitable for the growth of fish and shellfish in the breeding aquarium can be obtained relatively easily by the fish and shellfish cultivation apparatus according to the present invention.

  Next, the purification method for fish and shellfish culture water according to the present invention will be described.

  The method for purifying fish and shellfish culture water according to the present invention includes a step of generating microbubbles of gas containing ozone in the water to be purified in the breeding aquarium. More specifically, microbubbles of gas containing ozone may be generated in the water to be purified by using a known method such as a pressure reduction method and a gas-liquid shear method. The microbubbles may be generated in the breeding aquarium or in a tank other than the breeding aquarium. For example, after the purified water in the breeding water tank is transferred to a purification tank different from the breeding water tank, gas microbubbles containing ozone may be generated in the purified water in the purification tank.

  The method for purifying fish and shellfish culture water according to the present invention preferably includes a step of floating microbubbles in the septic tank. More specifically, stable bubbles formed by generating microbubbles in the water to be purified in the septic tank and joining the microbubbles float to the vicinity of the surface of the water to be purified contained in the septic tank. If you can. In addition, the microbubbles generated in the water to be purified may be floated over a time period enough to remove solid organic substances and ammonium ions in the water to be purified.

The solid organic matter is adsorbed on the surface of the stable bubble of the microbubble that has floated to the vicinity of the water surface, and ammonium ions are adsorbed on the solid organic matter. Therefore, the stable foam which floated in the water surface vicinity is discharged | emitted from a septic tank to the exterior, and solid organic substance and ammonium ion are discharged | emitted out of the system with foam by performing foam separation which isolate | separates foam and water. Therefore, after foam separation, the content of solid organic substances and ammonium ions that adversely affect the growth of fish and shellfish is small, and clean purified water can be obtained. By sending purified water to the breeding tank, water having a quality suitable for the growth of fish and shellfish is supplied to the breeding tank. In addition, the purified water obtained after the foam separation may be processed in a post-treatment tank in order to make the purified water even cleaner.

  Next, the operation of the fish shellfish culture water purification apparatus according to the present invention will be described.

  Purified water containing solid organic matter and ammonium ions is accommodated in the septic tank of the fish shellfish culture water purifying apparatus according to the present invention. When microbubbles of gas containing ozone are generated in the water to be purified, the microbubbles themselves disappear in the water, and the ozone itself reacts with water to generate a large amount of hydroxyl radicals. These hydroxyl radicals and solid organic matter react to form a large amount of hydroxyl groups on the surface of the solid organic matter. By adsorbing ammonium ions in water to this hydroxyl group, the surface of the solid organic substance becomes hydrophobic. The solid organic substance having a hydrophobic surface adheres to the surface of the microbubble and floats to the vicinity of the water surface together with the stable foam of the microbubble. By removing the bubbles floating near the water surface from the septic tank, the solid organic matter attached to the surface of the foam and the ammonium ions attached to the hydroxyl groups on the surface of the solid organic matter can be simultaneously taken out from the water. Therefore, the purified water obtained after the foam separation treatment has less solid organic matter and ammonium ion content that adversely affect the growth of fish and shellfish than the purified water. As described above, by performing the foam separation treatment using the fish shellfish culture water purification apparatus according to the present invention, clean water suitable for fish shellfish cultivation can be easily obtained without harming the health of the organism. be able to.

  Next, examples will be described.

Example 1
In 700L of purified water containing solid organic matter in the breeding aquarium used for the cultivation of sturgeon, normal salt and ammonia water (so that the salinity of the purified water is 1% by mass and the ammonia nitrogen concentration is 2ppm) Japanese Pharmacopoeia Standard) was added. Next, the to-be-purified water was fed at a water volume of 30 L / hour to a septic tank that was a small water tank for experiments of about 10 L. Using an ozone gas generator and a microbubble generator, ozone gas microbubbles were generated in the water to be purified in the septic tank so that the ozone gas was injected under the condition of 4 L / min. After the microbubbles were floated in the water to be purified, the water containing the stable bubbles of microbubbles that had risen to the vicinity of the water surface was collected, and the ammonia nitrogen concentration in the water containing the stable bubbles was measured over time. The measurement result was as shown by the straight line indicated by “ozone gas” in FIG.

(Comparative Example 1)
An experiment was performed in the same manner as in Example 1 except that air was pressed into a microbubble generator instead of the ozone gas, and microbubbles were generated in the water to be purified. The measurement result of the ammonia nitrogen concentration in the water containing the stable foam was as shown by the straight line indicated by “air” in FIG.

  The experimental conditions used in Example 1 and Comparative Example 1 are shown in Table 1 below.

  As shown in FIG. 4, the concentration of ammonia nitrogen in the water containing stable foam formed by the microbubbles of ozone gas in Example 1 is the water containing stable foam formed by atmospheric microbubbles in Example 2. It was greater than the concentration of ammonia nitrogen. Thereby, it was confirmed in Example 1 that more ammonium ions were foam-separated from the water to be purified than in Example 2.

  Specifically, the removal rate of ammonia nitrogen from the water to be purified in Example 1 was about 0.5 mg / hour. On the other hand, the removal rate of ammonia nitrogen from the water to be purified in Comparative Example 1 was about 0.3 mg / hour. As a result, it was confirmed that in Example 1, the ability to remove ammonium ions present in water was improved by about 1.7 times compared to Comparative Example 1. From the above, it was confirmed that ammonium ions present in the water to be purified can be more efficiently removed by performing a foam separation operation using microbubbles of ozone gas.

  Further, it is visually confirmed that the same amount of suspended solids are suspended in the water containing the stable foam collected in Example 1 and the water containing the stable foam collected in Comparative Example 1. It was done. Thereby, it was confirmed that the solid organic substance which exists in to-be-purified water is removed by performing foam separation operation using the microbubble of ozone gas.

1,21,33 Fish and shellfish culture water purification device 2,22 Water supply pipe 3,23 Purified water 4,24 Septic tank 5 Submersible pump 6,26 Intake port 7,27 Discharge port 8 Microbubble generating nozzle 9 Air intake tube 10 Tube 11, 29, 34 Ozone gas generators 16, 17 Water pressure pump 19 Gas dissolution tank 20 Pipe 28 Gas injection pipe 30 Pump 31 Fish shell culture device 32 Breeding water tank 35 Rear treatment tank

Claims (9)

  A fish and shellfish culture water purification device for purifying purified water, which can generate microbubbles of ozone-containing gas in the purified water in the septic tank and remove solid organic matter and ammonium ions in the purified water Fish and shellfish culture water purification device.   The fish shellfish culture water purification apparatus according to claim 1, wherein the gas is a gas obtained by changing oxygen in the atmosphere into ozone.   The fish shellfish culture water purification apparatus according to claim 1 or 2, wherein the gas is press-fitted into a microbubble generator that generates microbubbles. A foam separator and an ozone gas generator,
The foam separation device includes: the septic tank; a water supply pipe disposed so as to be able to supply the purified water to the septic tank; and a water pressure feed pump that pumps the purified water provided in a part of the water supply pipe; A gas injection pipe provided so that the gas can be press-fitted into the water to be purified; and the microbubble generator for generating microbubbles of gas injected from the gas injection pipe into the water to be purified.
The fish shellfish culture water purification apparatus according to any one of claims 1 to 3, wherein the ozone gas generation device is connected to the gas injection pipe.   The fish shellfish culture according to any one of claims 1 to 4, wherein a breeding tank containing the purified water and the purified water in the breeding tank are provided so as to be supplied to the purified tank. A fish shell culture device, comprising: a water purification device.   The downstream of the said fish and shellfish culture water purification apparatus is provided with the back | latter stage processing tank in which the purified water after purified in the said fish and shellfish culture water purification apparatus is sent. Fish shell farming equipment.   A method for purifying fish and shellfish aquaculture water by generating microbubbles of ozone-containing gas in the water to be purified in a breeding aquarium and removing solid organic matter and ammonium ions in the water to be purified.   Supplying the purified water in the breeding aquarium to the septic tank, generating microbubbles of gas containing ozone in the purified water in the septic tank, and floating the microbubbles in the septic tank; A step of performing foam separation by discharging the microbubbles floating near the water surface to the outside of the septic tank, and a step of feeding water after performing the foam separation to a breeding water tank or a post-treatment tank. The method for purifying fish shellfish culture water according to claim 7.   The method for purifying fish shellfish culture water according to claim 7 or 8, wherein the gas is a gas obtained by changing oxygen in the atmosphere to ozone.

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