A recirculating aquaculture system

Abstract

The application relates to the technical field of aquaculture, and discloses a circulating water aquaculture system which comprises an aquaculture area, a filtering area and an adjusting area arranged in sequence; the discharged water in the aquaculture area is discharged into the filtering area for filtration, the filtered water in the filtering area is discharged into the adjusting area, ecological bacteria algae are added into the adjusting area, and the water in the adjusting area is discharged into the aquaculture area after being treated by the ecological bacteria algae. The application can recycle the water and reduce the aquaculture cost.

Description

Technical Field

[0001] This application relates to the technical field of aquaculture, and in particular to a recirculating aquaculture system. Background Technology

[0002] Currently, some fish, such as eels, are highly favored by consumers due to their high nutritional value and delicious taste. To address the market demand exceeding supply, aquaculture has also developed rapidly. Aquaculture is currently in a period of rapid development and is gradually becoming industrialized and modernized, thus providing the market with more aquatic products. In the farming process, eels, for example, have high requirements for water quality; therefore, maintaining good water quality in the farming ponds is essential to improve survival rates and eel quality.

[0003] However, regularly discharging wastewater from aquaculture ponds and refilling them with clean water consumes a significant amount of water resources. Therefore, relevant technologies typically involve discharging the wastewater from the ponds, subjecting it to sedimentation, filtering it, and then re-introducing the filtered water back into the ponds for reuse.

[0004] The effluent discharged from aquaculture ponds also contains components such as nitrogen, phosphorus, and nitrite, which are not easy to treat during sedimentation and filtration. During water recycling, these components can have an adverse effect on the content levels of the components in the aquaculture ponds. Summary of the Invention

[0005] In order to enable water recycling and improve water quality treatment to make it more suitable for aquaculture, this application provides a recirculating aquaculture system.

[0006] This application discloses a recirculating aquaculture system, which adopts the following technical solution:

[0007] A recirculating aquaculture system includes an aquaculture zone, a filtration zone, and a regulating zone arranged sequentially. Wastewater from the aquaculture zone is discharged into the filtration zone for filtration. The filtered water is then discharged into the regulating zone, where ecological bacteria and algae are added. The water in the regulating zone is treated by the ecological bacteria and algae before being discharged back into the aquaculture zone.

[0008] By adopting the above technical solution, the aquaculture area is used for raising eels and other aquaculture species. During the aquaculture process, wastewater needs to be discharged and clean water needs to be added. The wastewater mainly contains eel feces. The wastewater from the aquaculture area is discharged into a filtration zone for sedimentation, which removes most of the particulate impurities. The filtered wastewater then enters a conditioning zone where ecological bacteria and algae are added. Since the wastewater contains nitrogen, phosphorus, and some nitrites and other nutrients, the addition of ecological bacteria and algae allows these components to be fully absorbed and utilized, promoting the growth of the bacteria and algae themselves, purifying the water, and inhibiting the growth of harmful bacteria.

[0009] Ecological bacteria and algae are rich in nutrients such as protein, vitamins, growth factors, and immune factors. Water from the regulation zone is then discharged back into the aquaculture zone, ensuring water quality. Furthermore, the ecological bacteria and algae can serve as feed for the fish, enhancing their immunity. Therefore, after filtration and treatment with ecological bacteria and algae, water can be recycled, water quality maintained, and healthy feed provided for the fish.

[0010] Optionally, the aquaculture system further includes a clear water zone located between the filtration zone and the conditioning zone. The discharged water enters the clear water zone from the filtration zone and then enters the conditioning zone. The clear water zone is connected to one or both of an ozone generator and an oxygen generator.

[0011] By adopting the above technical solution, the clear water zone is located between the filtration zone and the conditioning zone. Filtered water can enter the clear water zone for buffering and then be discharged into the conditioning zone according to the water volume, making the entire system more flexible and easier to control. The clear water zone is also connected to one or both of an ozone generator and an oxygen generator. The ozone generator provides ozone to the water, which is beneficial for sterilization, disinfection, and deodorization, making the water from the clear water zone more conducive to the growth of algae and bacteria when it enters the conditioning zone. The oxygen generator increases the oxygen content of the water in the clear water zone, which is also beneficial to the growth of algae and bacteria in the subsequent conditioning zone.

[0012] Optionally, the filtration zone includes a sedimentation tank and a filtration tank, and the filtration tank is equipped with filter elements; the water discharged from the aquaculture zone enters the sedimentation tank, then flows into the filtration tank and is filtered by the filter elements; the water filtered by the filtration tank flows into the clear water zone.

[0013] By adopting the above technical solution, the filtration area includes a sedimentation tank and a filtration tank. The water discharged from the aquaculture area first enters the sedimentation tank for sedimentation, where some particulate matter such as feces can be settled and most of it removed. Then the water is passed into the filtration tank and filtered through the filter elements to remove most of the particulate impurities in the water, which is convenient for subsequent water treatment.

[0014] Optionally, the aquaculture system further includes a sludge treatment area, which includes a sludge collection tank, an air flotation zone, and a sludge tank arranged in sequence. The sludge filtered out in the filtration zone is discharged into the sludge collection tank and then discharged into the air flotation zone for air flotation. The clear water in the upper layer of the air flotation zone is discharged into the clear water zone, and the sediment in the air flotation zone is discharged into the sludge tank.

[0015] By adopting the above technical solution, most of the sludge and impurities obtained from the filtration zone are mixed with water. These products from the filtration zone are first discharged into the sludge collection tank, and then discharged into the flotation zone for flotation treatment. In the flotation zone, the treated sediment settles at the bottom of the flotation zone, while the upper layer of clear water is discharged into the clear water zone, thereby improving the water recycling rate. The sludge enters the sludge tank for further sludge treatment, and the treated sludge can be used as fertilizer, etc.

[0016] Optionally, the algae in the ecological bacteria and algae are selected from one or two of Chlorella and diatoms; the bacteria are selected from one or more of photosynthetic bacteria, Bacillus, and complex bacteria.

[0017] By adopting the above technical solutions, diatoms, a type of phytoplankton rich in silicon and other nutrients, can be used as feed to improve the nutritional value of fish. They can also convert some components in the water into substances needed for their own growth, thereby purifying the water. Photosynthetic bacteria can also degrade substances such as nitrite in the water, thus purifying the water. Furthermore, as food, they can improve the immunity of fish and promote their growth.

[0018] Optionally, the sedimentation tank includes a tank body, on which a first spiral strip and a second spiral strip are installed. The first and second spiral strips are spirally distributed, with the upper end of the first spiral strip located above the upper end of the second spiral strip, forming a spiral channel between the first and second spiral strips. An inlet pipe and a drain pipe are installed on the side wall of the tank body. The outlet direction of the inlet pipe extends to the upper opening of the spiral channel, and the inlet pipe extends in a direction parallel to the tangential direction of the spiral channel. A material discharge groove is spaced apart on the second spiral strip. The drain pipe is located on the upper side wall of the tank body.

[0019] By adopting the above technical solution, the inlet pipe extends tangentially along the upper end of the spiral channel, allowing the sewage entering the inlet pipe to be directly flushed into the spiral channel and, guided by the spiral channel, flows spirally downwards. A discharge trough is provided on the second spiral strip, allowing particulate matter in the sewage to move downwards and settle during the spiral downward flow of the sewage. The liquid surface at the upper end of the tank is discharged through the drain pipe. Under the action of the spiral channel, the amount of particulate matter flowing away with the drain pipe can be reduced, thus facilitating the subsequent filtration steps.

[0020] Optionally, the second spiral is inclined upward towards the center of the pool body, and slots are provided at intervals at the connection between the second spiral and the inner wall of the pool body.

[0021] By adopting the above technical solution, the second spiral bar is inclined upward towards the center of the pool, so that when the sewage flows in the spiral channel, the particulate matter can settle towards the inner wall of the pool more easily, and gradually settle downward to the bottom of the pool through the groove.

[0022] Optionally, the width of the first spiral strip is greater than the width of the second spiral strip, and a baffle is provided on the side of the first spiral strip away from the inner wall of the pool, the baffle being inclined toward the second spiral strip.

[0023] By adopting the above technical solution, the width of the first spiral strip is greater than that of the first spiral strip, and an inclined strip is provided on the first spiral strip. During the flow of sewage in the spiral channel, under the action of the first spiral strip and the inclined strip, particulate impurities in the sewage are less likely to run to the center of the pool, but are more conducive to the downward sedimentation of particulate impurities.

[0024] Optionally, the first spiral strip is provided with openings spaced apart.

[0025] By adopting the above technical solution, when sewage flows in the spiral channel, the opening on the first spiral strip can also allow water to flow through, thereby reducing the water flow in the pool from flushing particulate impurities out of the spiral channel.

[0026] Optionally, the bottom of the pool body has a structure that is wider at the top and narrower at the bottom.

[0027] By adopting the above technical solution, the bottom of the pool has a structure that is larger at the top and smaller at the bottom, which is more conducive to the sedimentation of particulate impurities at the bottom of the pool.

[0028] In summary, this application includes at least one of the following beneficial effects:

[0029] 1. Wastewater from the aquaculture area, carrying feces, is discharged into the filtration zone for filtration and impurity removal. The filtered water is then discharged into the conditioning zone, where it is treated by ecological bacteria and algae. This process purifies the water, removes nitrogen and phosphorus, and promotes the growth of the bacteria and algae. The purified water and the bacteria and algae from the conditioning zone are then discharged into the aquaculture area together, thereby improving the efficiency of water recycling. The bacteria and algae also serve as healthy feed for the fish and can enhance their immunity.

[0030] 2. In the sedimentation tank, there is a spiral downward channel on the inner wall of the tank. Wastewater can flow downward along the spiral channel. During the process of the wastewater flowing along the spiral channel, particulate impurities in the wastewater can be settled downward through the feed chute. Under the guiding effect of the spiral channel, the material can be reduced from being disturbed, so that when the water in the tank overflows from the drain pipe, there are relatively few particulate impurities. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of an embodiment of this application;

[0032] Figure 2 This is a schematic diagram of the sedimentation tank in an embodiment of this application;

[0033] Figure 3 This is a cross-sectional schematic diagram of the sedimentation tank in an embodiment of this application.

[0034] Explanation of reference numerals in the attached diagram: 1. Aquaculture area; 2. Filtration area; 21. Sedimentation tank; 211. Tank body; 22. Filtration tank; 3. Adjustment area; 4. Ecological bacteria and algae; 5. Clear water area; 6. Sludge treatment area; 61. Sludge collection tank; 62. Air flotation area; 63. Sludge tank; 64. Plate and frame filter press; 7. First spiral strip; 8. Second spiral strip; 9. Inlet pipe; 10. Drain pipe; 11. Feed chute; 12. Groove; 13. Baffle strip; 14. Opening; 15. Flocculant; 16. Spiral channel. Detailed Implementation

[0035] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0036] This application discloses a recirculating aquaculture system. (Refer to...) Figure 1The aquaculture system comprises a rearing zone 1, a filtration zone 2, and a conditioning zone 3, arranged sequentially. Rearing zone 1 is used for raising fish, such as eels. To maintain water quality in rearing zone 1, wastewater needs to be discharged and fresh water introduced. The wastewater discharged from rearing zone 1 contains a significant amount of impurities, such as fecal particles. By discharging the water from rearing zone 1 into filtration zone 2, the wastewater is filtered, removing particulate impurities. The filtered water is then discharged into conditioning zone 3 for further treatment.

[0037] Ecological bacteria and algae 4 are added to the conditioning zone 3. Conditioning zone 3 can include multiple conditioning tanks, allowing for the simultaneous treatment of larger volumes of water. Since the water filtered by filtration zone 2 still contains significant amounts of nitrogen, phosphorus, and inorganic salts, the addition of ecological bacteria and algae 4 to conditioning zone 3 allows the growth of these substances to be consumed and fully absorbed by the bacteria and algae, promoting their growth. Then, as needed, the water treated by the ecological bacteria and algae 4 in conditioning zone 3, along with the bacteria and algae, is discharged into aquaculture zone 1, thus achieving water recycling. Furthermore, the ecological bacteria and algae 4 discharged into aquaculture zone 1 can serve as fish food.

[0038] In a further embodiment, the algae in the ecological algae 4 can be selected from one or two of diatoms or Chlorella, or other algae that can be used to purify water. The bacteria in the ecological algae 4 can be selected from one or more of photosynthetic bacteria, Bacillus, and complex bacteria, or other beneficial bacteria that are beneficial to fish in purifying water and as bait. The ecological algae 4 not only has a good effect on water purification, but is also rich in protein and other substances, which can improve the immunity of fish and inhibit the growth of harmful bacteria when used as bait.

[0039] In a further embodiment, the aquaculture system also includes a clear water zone 5, which may be equipped with multiple clear water pools. Water filtered by the filtration zone 2 first enters the clear water zone 5 for buffering. When needed, the water in the clear water zone 5 is then transported to the regulating zone 3. The water transport can be configured according to specific circumstances, such as transporting through pipes with on / off valves, transporting through water pumps, or a combination of both. An ozone generator and / or an oxygen generator are connected to the clear water zone 5. The ozone generator is selected from ozone generators, and the oxygen generator is selected from oxygen generators. Preferably, both an ozone generator and an oxygen generator are connected simultaneously. The ozone generator can provide ozone to the clear water zone 5, thereby achieving sterilization and deodorization of the water. The oxygen generator can provide oxygen to the water, thereby helping to increase the oxygen content of the water entering the regulating zone 3 and transported to the aquaculture zone 1.

[0040] In a further embodiment, the filtration zone 2 includes a sedimentation tank 21 and a filtration tank 22. Water discharged from the aquaculture zone 1 first enters the sedimentation tank 21 for sedimentation, causing particulate impurities in the water to settle. Then, it flows into the filtration tank 22 for further filtration to remove impurities. In this embodiment, a filter element is installed in the filtration tank 22. After the water enters the sedimentation tank 21, the filter element filters out impurities. The filter element can be a filter screen, filter cloth, fiber filter, etc. Because fiber filters have advantages such as good filtration effect and ease of cleaning, a fiber filter is preferred in this embodiment.

[0041] Furthermore, the aquaculture system also includes a sludge treatment zone 6, where sediment discharged from sedimentation tank 21 is treated. The sludge treatment zone 6 includes a collection tank 61, a flotation zone 62, and a sludge tank 63 arranged sequentially. The sediment discharged from sedimentation tank 21 carries a significant amount of water and is discharged into the collection tank 61 for buffering. The flotation zone 62 is equipped with a flotation machine, and the sludge from the collection tank 61 is pumped to the flotation zone 62 for treatment.

[0042] An air flotation machine is installed in the air flotation zone 62. Sludge from the collection tank 61 is discharged into the air flotation machine, where flocculant 15 is added to improve sedimentation. Preferably, flocculant 15 is selected from biological flocculants. The sediment from the air flotation machine is discharged into the sludge tank 63, while the supernatant is discharged into the clear water tank for further water recycling. Biological flocculant 15 is environmentally friendly and harmless to organisms, thus not negatively impacting water recycling. It also has good flocculation effects, facilitating the sedimentation of impurities. The sediment in the sludge tank 63 can be dewatered using a plate and frame filter press 64. The filter cake is collected and reused, for example, as fertilizer. The water squeezed out during the filtration process is discharged back into the collection tank 61 for further water recycling.

[0043] Reference Figure 1 and Figure 2 In a further embodiment, the sedimentation tank 21 includes a tank body 211. An inlet pipe 9 and an outlet pipe 10 are installed on the side wall of the tank body 211. Water from the aquaculture area 1 is discharged into the tank body 211 through the inlet pipe 9 and discharged through the outlet pipe 10, flowing into the filter tank 22. A first spiral strip 7 and a second spiral strip 8 are installed on the inner wall of the tank body 211. Both the first spiral strip 7 and the second spiral strip 8 are spirally arranged downwards along the inner wall of the tank body 211, and are arranged parallel to each other. The upper end of the first spiral strip 7 is higher than the upper end of the second spiral strip 8. That is, the starting point of the downward spiral of the first spiral strip 7 is higher than the starting point of the second spiral strip 8, so that a spiral channel 16 can be formed between the first spiral strip 7 and the second spiral strip 8.

[0044] Combination Figure 3 The drain pipe 10 is installed on the upper inner wall of the pool body 211, and the inlet pipe 9 is installed in the middle of the pool body 211, with the inlet of the inlet pipe 9 facing the upper opening of the spiral channel 16, and the water inlet direction of the inlet pipe 9 being parallel to the tangential direction of the spiral channel 16. Multiple material drop troughs 11 are spaced apart on the second spiral strip 8. The length of the first spiral strip 7 is less than the length of the second spiral strip 8, and the end of the first spiral strip 7 is located directly above the tail of the first spiral strip 7. That is, the first spiral strip 7 is spirally arranged around the inner wall of the pool body 211, while the second spiral strip 8 continues to spiral downwards. When sewage enters through the spiral channel 16, the water flows downwards along the spiral channel 16 under the guidance of the spiral channel 16, and particulate impurities in the water fall downwards from the material drop troughs 11.

[0045] Reference Figure 3 Furthermore, the second spiral 8 is inclined upwards towards the center of the pool body 211, and slots 12 are spaced apart at the connection between the second spiral 8 and the inner wall of the pool body 211. When sewage flows in the spiral channel 16, particulate impurities can easily fall into the slots 12. Furthermore, the width of the first spiral 7 is greater than the width of the second spiral 8, and a downwardly inclined baffle 13 is installed on the side of the first spiral 7 away from the inner wall of the pool body 211, and the baffle 13 is inclined towards the direction of the second spiral 8. There is a gap between the end of the baffle 13 away from the first spiral 7 and the second spiral 8, and the extension line of the baffle 13 can coincide with the second spiral 8. Under the action of the baffle 13, when sewage flows in the spiral channel, particulate impurities are less likely to escape from the spiral channel. Furthermore, the first spiral strip 7 is provided with openings 14 spaced apart. The pores of the openings 14 are smaller than the size of the fecal particles. When the sewage flows downward from the spiral channel, the water can pass through the openings 14, thereby reducing the amount of water flowing into the spiral channel from the inner cavity of the pool body 211. The fluid passing through the openings 14 helps the particles settle downward from the discharge trough 11.

[0046] The bottom of the tank 211 is preferably designed with a structure that is wider at the top and narrower at the bottom. This facilitates the sedimentation of particulate impurities, and the sewage flows downwards in a spiral, gradually reducing the flow velocity. This makes it less likely to stir up the sediment at the bottom of the tank 211, thus reducing the amount of particles in the water discharged from the upper part of the tank 211 through the drain pipe 10, reducing the burden on the subsequent filter elements and improving filtration efficiency. A sludge discharge pipe is connected to the bottom of the tank 211 for discharging the sediment from the bottom of the tank 211.

[0047] The implementation principle of a recirculating aquaculture system according to an embodiment of this application is as follows: the water discharged from the aquaculture area 1 is filtered in the filtration area 2, and the filtered water enters the conditioning area 3 after passing through the clear water area 5. After being purified by ecological bacteria and algae 4, it is discharged back into the aquaculture area 1, so that the water can be recycled and reused. The ecological bacteria and algae 4 can be used as feed to promote the growth of fish.

[0048] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A recirculating aquaculture system, characterized by: The system comprises a culture area (1), a filtering area (2) and an adjusting area (3) arranged in sequence; the discharge water in the culture area (1) is discharged into the filtering area (2) for filtering, the filtered water in the filtering area (2) is discharged into the adjusting area (3), ecological bacteria and algae (4) are added in the adjusting area (3), and the water in the adjusting area (3) is treated by the ecological bacteria and algae (4) and then discharged into the culture area (1); The culture system further comprises a clean water area (5) located between the filtering area (2) and the adjusting area (3), and the discharge water enters the clean water area (5) from the filtering area (2) and then enters the adjusting area (3), and one or both of an ozone generating device and an oxygen generating device is connected to the clean water area (5); The filtering area (2) comprises a sedimentation tank (21) and a filtering tank (22), and a filtering element is arranged in the filtering tank (22); the water discharged from the culture area (1) enters the sedimentation tank (21) and then flows into the filtering tank (22) and is filtered by the filtering element; the filtered water in the filtering tank (22) flows into the clean water area (5); The sedimentation tank (21) comprises a tank body (211), a first spiral strip (7) and a second spiral strip (8) are arranged on the inner wall of the tank body (211), the first spiral strip (7) and the second spiral strip (8) are arranged in a spiral shape, the upper end of the first spiral strip (7) is located above the upper end of the second spiral strip (8), and a spiral channel (16) is formed between the first spiral strip (7) and the second spiral strip (8); a water inlet pipe (9) and a drain pipe (10) are arranged on the side wall of the tank body (211), the discharge direction of the water inlet pipe (9) extends to the upper end opening of the spiral channel, and the water inlet pipe (9) extends along a tangential direction parallel to the spiral channel; a discharging groove (11) is arranged on the second spiral strip (8) at intervals; the drain pipe (10) is located on the upper end side wall of the tank body (211); The length of the first spiral strip (7) is less than the length of the second spiral strip (8), and the end of the first spiral strip (7) is located directly above the tail of the first spiral strip (7); The second spiral strip (8) is inclined upward to the center of the tank body (211), and a slot (12) is arranged at intervals at the connection between the second spiral strip (8) and the inner wall of the tank body (211); The width of the first spiral strip (7) is greater than the width of the second spiral strip (8), and a blocking strip (13) is arranged on the side of the first spiral strip (7) away from the inner wall of the tank body (211), and the blocking strip (13) is inclined to the second spiral strip (8).

2. A recirculating aquaculture system according to claim 1, wherein: The aquaculture system further comprises a sludge treatment area (6), which comprises a collecting pool (61), a air flotation area (62) and a sludge pool (63) arranged in sequence; the sludge filtered in the filtering area (2) is discharged into the collecting pool (61) and then discharged into the air flotation area (62) for air flotation, the clean water in the upper layer of the air flotation area (62) is discharged into the clean water area (5), and the precipitate in the air flotation area (62) is discharged into the sludge pool (63).

3. A recirculating aquaculture system according to claim 2, wherein: The algae in the ecological bacteria-algae (4) are selected from one or both of Chlorella and diatom; the bacteria are selected from one or more of photosynthetic bacteria spore bacteria and complex bacteria.

4. A recirculating aquaculture system according to claim 3, wherein: The first spiral strip (7) is provided with open holes (14) at intervals.

5. A recirculating aquaculture system according to claim 4, wherein: The bottom of the pool body (211) is in a structure of large at the top and small at the bottom.

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