KR20110111126A - A recirculating aquaculture system - Google Patents

Abstract

The present invention relates to a circulating filtration culture system that can reduce the carbon dioxide which is a fundamental cause of the pH drop of the breeding water in the process of circulating the breeding water,
A degassing device is provided to remove carbon dioxide from the breeding water, removes the carbon dioxide from the breeding water introduced from the reservoir, and then re-uses the carbon dioxide contained in the breeding water to be reused through a circulation structure in which the carbon dioxide is removed to the reservoir. It characterized in that to reduce.

Description

A recirculating aquaculture system

The present invention relates to a circulating filtration culture system, and more particularly, to a circulating filtration culture system that can reduce the carbon dioxide which is a fundamental cause of the pH drop of the breeding water in the process of circulating the breeding water.

In Korea, the cold water temperature is long during the winter, which limits the productivity of farmed fish. In particular, in the case of hot water fish, the operation of the heating device is essential, and a large portion of the production cost generated therein is at work. In addition, due to geographical conditions, it is difficult to secure the surface area of fish farms, so a high density farming which can produce a large amount of fish in a small area is essential.

Accordingly, the circulating filtration culture system that can maintain a stable water environment through water recycling and various water treatment processes is commercialized because it can produce fish with high energy saving effect and high density.

The circulating filtration system is a system for continuously circulating water in a breeding tank and breeding fish while filtering filth, and as shown in FIG. 8, the breeding tank of the breeding tank 100 passes through the settling tank 200. While the solids discharged with the breeding water is first removed, collected in the reservoir 300, the breeding water introduced into the reservoir 300 is again passed through the foam separator 500 through the pump 400 to fine organic matter This is removed, and finally, after toxic dissolved substances such as ammonia and nitrous acid remaining in the breeding water through the biofiltration tank 600 is purified, it is re-introduced into the breeding tank 100 and reused as breeding water.

However, the conventional circulating filtration culture apparatus as described above has a problem in that the pH is continuously reduced by performing high density breeding using only a small amount of birds of about 5 to 10% per day as breeding water, such a decrease in pH. Inhibits the growth and metabolism of aquaculture organisms, and the ability of hemoglobin in the blood to bind with oxygen decreases, resulting in a suffocation of breeding organisms despite the availability of sufficient dissolved oxygen.

In addition, nitrifying bacteria in biofiltration tanks consume about 7.14g of alkalinity to oxidize 1g of ammonia, which, like aquaculture organisms, does not perform normal nitrification at low pH. This can result in lower productivity and a large loss of production organisms.

In order to supplement the alkalinity in the water, bicarbonate was continuously added to the breeding water to prevent a decrease in pH. However, when the bicarbonate was supplied at a commercial scale, it should supply about 50 to 60% of the daily feed amount. Since a large amount of bicarbonate must be supplied such that the pH can be stably maintained, the cost has been greatly increased.

Therefore, in order to prevent the pH drop in the water, rather than supplying a supplement such as bicarbonate it was necessary to solve the main cause that can prevent the pH drop while reducing the amount of the supplement as described above.

The main reason for the decrease in pH in the water of the breeding tank is dissolved carbon dioxide produced by the metabolism of nitrifying bacteria in aquaculture organisms and biofiltration tanks.

Carbon dioxide exists mainly in the form of bicarbonate in the blood of aquaculture organisms, but it is converted into carbon dioxide form and released into water by enzymatic activity in gills. As such, when carbon dioxide is released into the water, the concentration of carbon dioxide in the water is increased to reduce the difference in the concentration of carbon dioxide in and out of the gills, thereby making it difficult to diffuse carbon dioxide through the gills, thereby increasing the concentration of carbon dioxide in the blood and the pH of the blood. Lowers.

Due to the above phenomenon, even if there is enough oxygen in the water, the amount of oxygen that can be transported by the hemoglobin in the blood decreases, and the asphyxiation of breeding organisms appears. Also, when excessive carbon dioxide is dissolved in the blood, nephorocalcinosis is caused. Controlling carbon dioxide is a very important factor in determining overall production efficiency in dense breeding systems in that it can cause and impede the delivery of oxygen into the blood.

Therefore, it is necessary to develop a water treatment apparatus to prevent excessive accumulation of carbon dioxide in the water during aquaculture through a circulating filtration aquaculture system.

The present invention is to solve the above problems,

The aim of the present invention is to provide a circulating filtration aquaculture system that can reduce the amount of bicarbonate and prevent excessive accumulation of carbon dioxide to secure a stable marine living environment.

Another object of the present invention is to facilitate the flow of breeding water.

According to an aspect of the present invention,

In a circulating filtration system,

It provides a circulating filtration culture system characterized in that the degassing device for removing the carbon dioxide in the breeding water.

In addition, the degassing device is characterized in that the circulating structure to remove the carbon dioxide of the breeding water introduced from the reservoir, the carbon dioxide is removed to send the breeding water back to the reservoir.

In addition, the degassing device is characterized in that the breeding water introduced into the upper portion is supplied to the water tank through the medium, the carbon dioxide in the breeding water is separated by the air introduced from the lower portion to the upper portion when the breeding medium passes through the medium is discharged to the outside do.

In addition, the degassing apparatus has a carbon dioxide outlet and breeding water inlet is formed in the upper portion, the air inlet and the breeding water outlet formed in the lower portion;

An air blower for sending air to an air inlet of the main body;

It characterized in that it comprises a medium provided inside the main body.

The medium may be formed by stacking two or more horizontal plates on which a plurality of through holes are formed.

In addition, the medium is characterized in that a plurality of vertical tubes made of a plurality of vertical tubes or nets with micropores formed.

As described above, the circulating filtration culture system according to the present invention continuously removes the carbon dioxide contained in the breeding water through the degassing apparatus, passes through the circulating process in which the breeding water from which the carbon dioxide is removed is sent back to the reservoir, and as a result, the reservoir It is possible to reduce the amount of carbon dioxide in the breeding water stored in the, and when the carbon dioxide reduced breeding water is passed through the foam separator to the breeding tank can solve the problem of the pH drop of the breeding water caused by the increase of carbon dioxide in the conventional breeding tank. As a result, there is an effect of preventing the loss of productivity of aquaculture organisms and the loss of asphyxiation.

Therefore, the flow of the breeding water can be smooth due to the vertical tube-type medium with fine pores, thereby improving the contact area between the breeding water and the air without interrupting the flow of water, thereby removing carbon dioxide contained in the breeding water. Efficiency has the effect of raising.

1 is a conceptual diagram showing a circulating filtration culture system according to an embodiment of the present invention.
Figure 2 is a conceptual diagram showing a degassing apparatus of the circulation filtration culture system of Figure 1;
3 is a conceptual diagram showing a degassing apparatus of the circulating filtration culture system according to another embodiment of the present invention.
Figure 4 is a diagram showing the contour of the carbon dioxide removal rate for each degassing apparatus of Experimental Example 1 according to the hydraulic load and air / rearing ratio.
FIG. 5 is a diagram illustrating a carbon dioxide daily removal amount of each degassing apparatus of Experimental Example 1 according to a hydraulic load and an air / breeding quantity ratio in a contour graph. FIG.
Figure 6 is a graph showing the change in the concentration of ammonia, nitrite, phosphorus phosphate during abduction fry breeding in the experimental and control groups before operating the degassing apparatus.
Figure 7 is a graph showing the pH change and the amount of sodium bicarbonate in the breeding tank according to the operation of the degassing device during the breeding of the abduction toothfish.
8 is a conceptual diagram showing a conventional circulating filtration system.

Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the accompanying drawings, but the present invention is not limited to the embodiments shown in the drawings.

1 is a conceptual diagram showing a circulating filtration culture system according to an embodiment of the present invention, Figure 2 is a conceptual diagram showing a degassing apparatus of the circulating filtration culture system of FIG.

As shown therein, the present invention is provided with a degassing apparatus 10 for removing carbon dioxide from breeding water in a general circulation filtration culture system, and the present invention provides a pH of the circulation filtration culture system through the degassing apparatus 10. The main reason for the reduction is to prevent production efficiency decreases, such as suffocation of aquaculture organisms, and to reduce the use of chemicals such as bicarbonate, so that eco-friendly and economical aquaculture systems can be operated.

Looking in more detail based on Figure 1, the circulating filtration culture system according to the present invention breeding tank 20, sedimentation tank 30, reservoir tank 40, pump 50, foam separator 60, biological filtration tank 70 ), And a degassing apparatus 10.

Here, the breeding tank 20 is a part where the actual organism is bred, and the settling tank 30 primarily removes the solids of the breeding water containing various wastes generated in the breeding process of the organisms supplied from the breeding tank 20. It is a part, the reservoir 40 is a portion in which the breeding water supplied directly from the breeding water or the breeding water tank 20 from which the solids are removed from the settling tank 30 is stored. In addition, the foam separator 60 is a portion for removing the fine organic matter is supplied to the breeding water of the reservoir 40 through the pump 50, the biofiltration tank 70 is left in the breeding water passed through the foam separator 60 Toxic dissolved substances such as ammonia, nitrous acid is the part to be purified, and the purified water thus completed is re-introduced into the breeding tank 20 is reused. Breeding water tank (20), sedimentation tank (30), reservoir (40), pump (50), foam separator (60), biological filtration tank (70) of such a circulation filtration aquaculture system because they are generally used In the present invention, a more detailed description thereof will be omitted.

The degassing apparatus 10 of the present invention is provided in the general circulating filtration culture system as described above to remove or reduce carbon dioxide, and more specifically, the degassing apparatus 10 is carbon dioxide of breeding water introduced from the reservoir 40. After removing the, the carbon dioxide is removed is the circulation structure to send the breeding water back to the reservoir (40).

That is, the breeding water stored in the reservoir 40 is introduced into the deaerator 10 through the pump 50, and after the carbon dioxide of the breeding water introduced into the deaerator 10 is removed, the reservoir 40 is again. As shown in FIG. 1, the degassing apparatus 10 of the present invention is disposed between the reservoir 40 and the foam separator 60 so that some water is directly passed through the pump 50 to the foam separator 60. ) Is supplied to the degassing apparatus (10) to be able to remove the carbon dioxide, but the arrangement is not limited to this, the breeding water of the reservoir (40) passes through the degassing apparatus (10) It can be arranged in a structure that can be circulated.

At this time, the degassing apparatus 10 is supplied to the storage tank 40 through the breeding water introduced into the upper portion 12, the air in which carbon dioxide in the breeding water flows from the lower portion to the upper portion when passing through the medium 12 of the breeding water It is separated by and discharged to the outside.

That is, when breeding water is supplied from the reservoir 40 to the degassing apparatus 10 through the pump 50 or the like, the breeding water is supplied from the upper portion of the degassing apparatus 10 to flow from the top to the bottom, and the breeding water degassing apparatus 10 When flowing through the flow path formed by the medium 12 installed in the) is aerated by a high-pressure air flowing from the lower portion of the degassing apparatus 10 to the upper part to separate the carbon dioxide in the breeding water, the separated carbon dioxide is a high-pressure air Along with being discharged out of the deaerator 10, the breeding water from which carbon dioxide is removed through the aeration is discharged to the lower portion of the deaerator 10 is supplied to the reservoir 40 again.

To this end, as shown in FIG. 2, the degassing apparatus 10 of the present invention has a carbon dioxide outlet 141 and a breeding water inlet 143 formed at an upper portion thereof, and an air inlet 145 and a breeding water outlet 147 formed at a lower portion thereof. And a main body 14 formed with; An air blower (16) for sending air to the air inlet of the main body (14); And a medium 12 provided inside the main body 14.

That is, the breeding water of the reservoir 40 is supplied into the main body 14 of the degassing apparatus 10 through the breeding water inlet 143 of the main body 14, and the supplied breeding water passes through the medium 12. It flows from the top to the bottom, and the high-pressure air from the air blower 16 is supplied from the bottom of the deaerator 10 through the air inlet 145 in the lower part of the main body 14 to be contained in the breeding water as aeration. As the separated carbon dioxide is separated, the carbon dioxide contained in the breeding water is removed.

In addition, the carbon dioxide separated by such high-pressure air flows into the carbon dioxide outlet 141 at the upper portion of the main body 14 to be discharged to the outside, and the breeding water from which the carbon dioxide is removed is again located at the lower part of the main body 14. Is discharged through the breeding water outlet 147 is sent to the reservoir (40).

Here, the air blower 16 serves to supply external air into the main body through a conventional air supply device, and the air blower 16 is generally operated for oxygen supply in a biofiltration tank of aquaculture apparatus. The device may be installed below the deaerator 10 so that air is supplied through the pipe.

The circulating filtration-type aquaculture system equipped with the above degassing apparatus continuously removes the carbon dioxide contained in the breeding water through the degassing apparatus, and goes through the circulating process in which the breeding water from which the carbon dioxide has been removed is sent back to the reservoir, from the breeding tank. The breeding water containing carbon dioxide supplied and the breeding water without carbon dioxide supplied through the deaerator may be mixed, resulting in a reduction in the amount of carbon dioxide in the breeding water stored in the reservoir, thus reducing the carbon dioxide in the foam separator When passed through the breeding tank can solve the problem of lowering the pH of the breeding water caused by the increase of carbon dioxide in the conventional breeding tank, thereby preventing the loss of productivity or suffocation of aquaculture organisms.

In this case, the medium 12 of the present invention is preferably formed by stacking two or more horizontal plates on which a plurality of through holes 123 are formed, as shown in FIG. 2.

More specifically, the horizontal plate is formed with a plurality of through holes 123, a plate of a plastic thin film or net form having micropores may be used, and a plurality of such horizontal plates are formed in the body 14 to form a degassing apparatus. Used as a medium.

Such a medium 12 has a plurality of through-holes 123 formed in the horizontal plate to form a channel through which the breeding water can flow from the top to the bottom, so that the breeding water is smoothly contacted with the high pressure air supplied from the degassing apparatus 10. Carbon dioxide is separated, and the carbon dioxide thus separated may be discharged to the outside of the degassing apparatus 10 by the high pressure air supplied from the lower portion of the degassing apparatus 10.

At this time, since the water molecules are relatively larger than the air molecules, only the breeding water from which carbon dioxide is removed by flowing down through the through holes formed in the horizontal plate can be supplied to the reservoir.

Therefore, it is possible to effectively remove the carbon dioxide contained in the breeding water through the medium as described above.

Figure 3 is a conceptual diagram showing a degassing apparatus of the circulating filtration culture system according to another embodiment of the present invention. As shown in the drawing, the medium 12 of the present invention is more preferably a plurality of vertical tubes formed of a plurality of vertical tubes or meshes in which the micropores 121 are formed.

More specifically, the vertical tube is made of a plastic thin film having micropores 121 or a mesh having a plurality of holes, and is a tube of a column shape through which the center is penetrated, and the plurality of vertical tubes are the medium of the degassing apparatus 12. Is used.

The medium 12 filters carbon dioxide through a plurality of micropores 121 or a plurality of holes formed in a mesh with high pressure air, and the carbon dioxide filtered by the micropores 121 or a plurality of holes. Is discharged to the outside of the degassing apparatus 10 by the high pressure air supplied from the lower degassing apparatus (10). At this time, since the water molecules are relatively larger than the air molecules, they are not filtered through the medium 12, and only the breeding water from which carbon dioxide is removed by flowing down through the through-holes formed in the vertical pipe can be supplied to the reservoir.

In addition, since the vertical tube-shaped medium 12 allows the flow of the breeding water to flow smoothly from the top to the bottom, the contact area between the air and the breeding water can be further expanded, thereby further improving carbon dioxide removal efficiency. Can be.

Therefore, the use of the above-described vertical tube-type medium can smoothly flow the breeding water so that it is not disturbed by the flow of water, and the contact area between the breeding water and the air increases, which further increases the removal efficiency of carbon dioxide contained in the breeding water. Can be raised.

The following experiment was performed to demonstrate the effect of the circulating filtration culture system according to the present invention.

Experimental Example 1

In order to evaluate the efficiency of the degassing apparatus according to the present invention, after connecting different types of degassing apparatuses to a pilot circulating filtration system of about 7 tons, the removal rate of carbon dioxide for each degassing apparatus was changed by varying the flow rate of the breeding water ( %) And daily removal amount of carbon dioxide (kgCO ₂ / m ₃ day) was measured, and the results are shown in Table 2 below. In addition, in order to more clearly identify the removal characteristics of carbon dioxide for each deaerator, the dehydrator of the deaerator is based on the hydraulic load based on the flow rate of the breeding water and the cross-sectional area of the deaerator and the air volume / breeding ratio (see Table 1). The carbon dioxide removal rate and the daily carbon dioxide removal amount were measured and modeled in a three-dimensional contour graph, and the results are shown in FIGS. 4 and 5.

Pilot circulating filtration system used in Experimental Example 1 includes two round breeding tanks (2.0 m L × 2.0 m W × 1.0 m D, 3,500 L capacity), one settling tank (0.45 m D × 1.0 m H), and a foam separator. 1 (0.3 m D × 2.5 m H), 1 sprinkled biological filtration tank (0.8 m D × 1.5 m H), 1 reservoir (0.3 m D × 1.0 m H), 1 circulation pump (0.75 kW), Venturi pump It was composed of one (0.75 kW), and the main body of each degassing device used in the experiment was 300 mm in diameter and 1 m in height, which was made of transparent acrylic pipe for easy internal observation.

At this time, the degassing apparatus used in Experimental Example 1 is as follows.

Comparative Example 1: Degassing apparatus without a medium.

Example 1 A degassing apparatus using a medium in which a net-shaped circular plate made of plastic is vertically laminated.

Example 2: A degassing apparatus using a medium in the form of a vertical tube through which a plastic thin film having a plurality of micropores formed therethrough.

division Breeding water flow rate (L / min) 5 10 20 Air flow
(L / min) 20 1: 4 1: 2 1: 1 80 1:16 1: 8 1: 4 160 1:32 1:16 1: 8

Medium

Air flow

(L / min) Breeding water flow rate (L / min) 5 10 20 Removal rate Removal Removal rate Removal Removal rate Removal Comparative Example 1

20 7.8 ± 1.7 0.80 ± 0.11 5.5 ± 0.8 1.06 ± 0.30 7.0 ± 3.9 2.65 ± 0.87 80 9.5 ± 0.6 1.13 ± 0.05 5.7 ± 0.6 1.03 ± 0.20 9.0 ± 1.0 2.25 ± 0.43 160 9.5 ± 0.6 0.10 ± 0.05 4.9 ± 0.1 1.06 ± 0.12 13.2 ± 0.5 2.39 ± 0.22 Example 1

20 13.2 ± 3.4 1.33 ± 0.22 12.9 ± 0.5 2.79 ± 0.11 6.9 ± 0.7 2.92 ± 0.22 80 12.3 ± 0.7 1.26 ± 0.05 17.1 ± 0.6 3.45 ± 0.40 9.8 ± 0.1 3.72 ± 0.10 160 18.3 ± 3.4 2.12 ± 0.22 21.0 ± 3.1 5.31 ± 0.43 13.0 ± 1.8 5.84 ± 0.43 Example 2

20 17.5 ± 0.4 2.06 ± 0.45 19.4 ± 3.6 9.82 ± 1.08 13.4 ± 3.8 6.37 ± 0.30 80 23.6 ± 0.3 2.46 ± 0.50 17.2 ± 0.4 7.43 ± 0.50 16.6 ± 0.7 7.17 ± 0.22 160 21.7 ± 2.0 2.19 ± 0.16 25.8 ± 7.5 10.35 ± 1.52 17.2 ± 4.7 6.64 ± 0.83

As shown in Table 2, when the air flow rate and the breeding water flow rate are the same, the carbon dioxide removal rate and the daily carbon dioxide removal amount of the pilot purifying filtration system using the degassing apparatus of Example 1 and Example 2 were used using the degassing apparatus of Comparative Example 1. It was confirmed that the carbon dioxide removal rate of the pilot filtration system and the daily carbon dioxide removal amount were increased. In addition, it can be seen that the pilot filtration system using the degassing apparatus of Example 2 rather than Example 1 significantly improved the carbon dioxide removal rate and the daily carbon dioxide removal efficiency.

On the other hand, as a result of examining the carbon dioxide removal characteristics according to the hydraulic load and air / breeding water ratio through Figures 4 and 5, in the case of the pilot purified filtration system using the degassing device of Comparative Example 1 the hydraulic load of about 400㎥ / day ㎡ and the air / breeding quantity ratio is more than 30 has the maximum effect of the maximum carbon dioxide removal rate and daily carbon dioxide removal amount, it can be seen that the carbon dioxide removal is achieved only when the amount of passage water per large cross-sectional area is large.

On the other hand, the pilot purifying filtration system using the degassing apparatus of Example 1 and Example 2 was confirmed that the range of the maximum carbon dioxide removal rate and the maximum daily carbon dioxide removal amount increased significantly compared to Comparative Example 1. In particular, in the case of the pilot purifying filtration system using the degassing apparatus of Example 2, the range showing the maximum carbon dioxide removal efficiency was a hydraulic load of 180 to 320 m 3 / m 2, and an air / breeding ratio of 10 to 21. Compared to the pilot filtration system using the degassing device of Comparative Example 1, the chemical load, air amount, and breeding quantity were significantly lower and showed higher carbon dioxide removal characteristics.

This is because the medium used in the degassing device of Example 2 is a vertical tube shape, the breeding water can flow smoothly downward, and the cross-sectional area in contact with the breeding water can be increased, so that the lower hydraulic load and the air quantity / breeding quantity can be increased. It is because it can have a high carbon dioxide removal characteristic even in the conditions having a ratio.

Experimental Example 2

In order to compare the flounder efficiency according to the installation of the degasser in the circulation filtration system, a total of 32 kg of flounder fry (average body weight of about 44 g) was added to the breeding tank of the circulation filtration system connected to the degasser of the second embodiment. After receiving it evenly, the flounder fry are bred for 37 days while feeding the compounded fish (50% protein content) for the flounder three times a day based on about 1.5% of the weight of the fish daily without degassing. During the next 31 days, abducted larvae were reared under the same breeding conditions with the degassing system in operation, and the growth efficiency of the flounder fry in the system, the pH change in the breeding tank, and the amount of sodium bicarbonate added were observed. Table 3, FIG. 6 and FIG. At this time, the abduction device was bred for 68 days under the same breeding conditions using the same circulation filtration system as the control group except that no degasser was connected.

The circulating filtration system used in the experiment and control was four square breeding tanks (1.0 m L × 1.0 m W × 1.0 m D, 600 L capacity), one reservoir tank of the same size as the breeding tank, and a settling tank (0.6 m D ×). 1.0 m H), 2 foam separators (0.3 m D × 2.5 m H), 1 Sprinkler biological filtration tank (1.5 m D × 2.0 m H), 1 circulating pump (0.75 kW), Venturi pump (0.75 kW) and the total quantity was about 4,500 L. The supernatant of the breeding water discharged from the breeding tank and the settling tank was introduced into the biological filtration tank through the foam separator, and the circulation water was adjusted to 150 L / min using a flow meter. The water that passed through the biological filtration tank was introduced back into the breeding tank by a drop. Sediment solids accumulated in the sedimentation tank were removed twice a day through a central drain installed at the bottom of the breeding tank. About 5-10% of the total volume was returned daily, replenishing the reduced quantity by discharging the solids into the settling tank. Breeding water temperature was maintained on average 21.6 during the experiment using an electric heater. Dissolved oxygen was maintained at 6.0 mg / L by injecting pure oxygen into each breeding tank and salinity was maintained at about 35 ppt.

However, in the circulating filtration system of the experimental zone, as shown in FIG. 1, a part of breeding water introduced into the circulating pump was re-introduced into the reservoir through the degassing apparatus, and the operating condition of the degassing apparatus was 320㎥ / M <2> and the air quantity / breeding quantity ratio was 10.

division Feed factor Feed efficiency (%) Daily growth rate (%) Survival rate (%) Experiment 0.95 ± 0.00 105.7 ± 0.2 1.65 ± 0.00 98.0 ± 1.2 Control 1.00 ± 0.02 100.3 ± 1.9 1.58 ± 0.02 97.9 ± 1.9

Table 3 shows the survival rate and growth rate of the flounder fry for 31 days in the control group and before the operation of the degasser, the survival rate and growth rate of the flounder larvae tended to be somewhat higher in the experimental group, There was no difference, and the presence of a degasser did not significantly affect the growth and survival of the abducted fry.

FIG. 6 is a graph showing changes in concentrations of ammonia, nitrous acid and phosphorus phosphate during kidnapping fry in experimental and control groups before operation of the degassing apparatus. The concentration of phosphorus is very low and stable to confirm that it does not affect the growth of flounder fry.

7 is a graph showing the pH change in the breeding tank and the amount of sodium bicarbonate added according to the operation of the degassing apparatus during the breeding of the abduction larvae, as shown in the 400g daily feed in the experimental and control groups before operating the degassing apparatus. 16 days after the start of feeding, the pH of the experimental and control groups can be seen to decrease to 7.5. The sodium bicarbonate was added to the experimental and control groups by 1 kg, respectively, and the pH of the two systems was increased again to 8.1. However, the pH was sharply increased again at 33 days of breeding, and sodium bicarbonate was added again 1 kg at 35 days, and the pH of the breeding water was increased in the experimental and control systems.

That is, 37 days before the degassing device was operated, it was confirmed that the pH change patterns of the experimental and control groups and the addition date and the amount of sodium bicarbonate, which are bicarbonates, showed the same increase and decrease patterns.

However, from the 38th day when the degassing device was operated to remove carbon dioxide, it was confirmed that the increase and decrease patterns of the control and control were different. From the 38th day, the amount of feed fed to the experimental and control groups was increased to about 800g per day.

More specifically, as the amount of feed increased, the control group had a sharp drop in pH from the beginning of the experiment. On the 45th day, the pH dropped to 7.4 and 1 kg of sodium bicarbonate was added, whereas in the experimental group, the pH was maintained at about 8.0. No additional sodium was added. Then, on day 48, the pH was drastically lowered in both the experimental and control groups, and 2 kg of sodium bicarbonate was added to raise the pH to about 8.0. In the control group, sodium bicarbonate was added by rapidly dropping the pH to 7.7 at about 55 days, whereas in the experimental group, the pH was drastically lowered by adding sodium bicarbonate at 61 days, and thus the sodium bicarbonate was added. The addition time and amount of the control group was confirmed that the experimental group is later.

In addition, in the control group, the ratio of sodium bicarbonate was about 24.7% and the average pH was 7.86 compared to the feeding amount from 38 days to 68 days after breeding, whereas in the experimental group, the ratio of sodium bicarbonate was 19.8%, As the pH was 7.91, the addition amount of sodium bicarbonate decreased about 5% compared to the control, but the average pH was maintained higher.

The degassing apparatus according to the circulating filtration culture system of the present invention through the results as described above can be seen that the effect on the pH of the breeding water through the removal of carbon dioxide, the degassing apparatus of the present invention is the scale as described above Although small and only about 10% of the total circulating water was treated, the results showed that the pH lowering effect and the sodium bicarbonate reduction effect. In addition, arithmetically evaluating the results, it can be predicted that the amount of bicarbonate added can be reduced by about 50% when converted to the scale applied in actual freshwater. Therefore, the circulating filtration culture system of the present invention can be usefully applied to the breeding of marine organisms such as maintaining a stable breeding environment by preventing the pH drop while reducing the use of bicarbonate.

10: degasser
12: medium 121: micropores
123: through
14: main body 141: carbon dioxide outlet
143: breeding water inlet 145: air inlet
147: Breeding water outlet 16: air blow
20: breeding tank
30: sedimentation tank
40: reservoir
50: pump
60: foam separator
70: biological filtration tank

Claims (6)

In a circulating filtration system,
Circulating filtration culture system, characterized in that the degassing device 10 for removing the carbon dioxide of the breeding water. The method according to claim 1,
The degassing apparatus (10) is a circulation filtration culture system, characterized in that after removing the carbon dioxide of the breeding water introduced from the reservoir 40, the carbon dioxide removed breeding water is sent back to the reservoir 40. The method according to claim 2,
The degassing apparatus 10 is supplied to the storage tank 40 through the breeding water introduced into the upper portion 12, and the carbon dioxide in the breeding water is introduced into the air flowing from the lower portion to the upper portion when the medium 12 of the breeding water passes. Circular filtration culture system characterized in that separated by the discharge to the outside. The method according to claim 3,
The degassing apparatus 10 includes a main body 14 having a carbon dioxide outlet 141 and a breeding water inlet 143 at an upper portion thereof, and an air inlet 145 and a breeding water outlet 147 at a lower portion thereof;
An air blower (16) for sending air to the air inlet (145) of the main body (14);
Circulating filtration culture system comprising a medium (12) provided inside the main body (14). The method according to claim 3 or 4,
The medium 12 is a circulating filtration culture system, characterized in that formed by stacking two or more horizontal plates formed with a plurality of through holes (123). The method according to claim 3 or 4,
The medium 12 is a circulating filtration culture system, characterized in that the micropores 121 is formed of a plurality of vertical tubes or a plurality of vertical tubes made of a net.

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