A bacteria-algae symbiotic biofilm reactor for treating mariculture effluent

Abstract

The application discloses a bacteria-algae symbiotic biofilm reactor for treating mariculture tail water, which comprises an outer shell, a first cylindrical partition and a second cylindrical partition, a filter area is formed between the outer shell and the first cylindrical partition, a biological filter bed is arranged in the filter area, a flow stabilizing mechanism is arranged between the first cylindrical partition and the second cylindrical partition, a water inlet area is formed between the flow stabilizing mechanism and the first cylindrical partition, a water inlet pipe is connected to the top of the water inlet area, a suspended filler area is formed between the flow stabilizing mechanism and the second cylindrical partition, a suspended filler is arranged in the suspended filler area, an aeration device is arranged at the bottom of the suspended filler area, the water inlet area and the suspended filler area are communicated through the flow stabilizing mechanism, the second cylindrical partition is transparent, a light source is arranged in the second cylindrical partition, a water distributor is arranged above the biological filter bed, a circulating pipe is arranged at the lower part of the suspended filler area, the circulating pipe is connected with the water distributor through a water pump, and a water outlet pipe is connected to the outer shell below the biological filter bed. The application has the advantages of convenient operation, small occupied area, low energy consumption, good impact load resistance performance and operation stability, and good treatment effect.

Description

Technical Field

[0001] This invention relates to the field of aquaculture wastewater treatment technology, and in particular to a symbiotic biofilm reactor for treating marine aquaculture wastewater. Background Technology

[0002] Pond aquaculture is a traditional method of marine aquaculture in my country and one of the main methods of aquaculture today, playing a crucial role in the development of aquaculture in my country. However, with the increase in aquaculture production, traditional pond aquaculture in my country has gradually encountered some problems, such as high-density farming and the excessive use of feed and veterinary drugs, which not only pollute the water itself but also lead to the deterioration of the surrounding aquatic ecosystem, even resulting in eutrophication. Therefore, in order to reduce the environmental pollution caused by aquaculture and ensure the healthy and sustainable development of the aquaculture industry, it is urgent to find a technology for treating aquaculture wastewater.

[0003] The bacterial-algae symbiotic system is a biological treatment technology that utilizes the physiological synergy between bacteria and algae to purify water. Under light conditions, algae absorb carbon dioxide released by bacterial respiration and synthesize nutrients for their own growth and reproduction through photosynthesis, while simultaneously releasing oxygen for bacterial metabolic activities. Furthermore, bacteria can mineralize and hydrolyze recalcitrant organic matter in the water into simpler substances such as ammonium, nitrogen, and phosphates, which are easily absorbed and utilized by algae, promoting algal growth. Algae, in turn, can provide bacteria with essential elements for growth, such as vitamin B12, through their metabolic products.

[0004] Currently, algal-microbe symbiotic systems mainly exist in suspended and immobilized forms. In suspended algal-microbe systems, due to the small size and density of microalgae close to that of water, they mostly exist in a suspended state in water, easily flowing out with the effluent, causing algal cell loss and affecting water treatment efficiency. Immobilization can effectively overcome the drawbacks of suspended algal-microbe systems, but it has not been widely used due to problems such as the high cost of encapsulation substrates, the difficulty in finding non-toxic and harmless substrates, and the cumbersome and complex operation. To overcome the technical bottlenecks of the above two types of algal-microbe symbiotic systems, algal-microbe symbiotic biofilm systems have emerged. By introducing an inert carrier into the water treatment system, and utilizing the directional adsorption characteristics of algal-microbes, a structurally stable algal-microbe symbiotic biofilm is formed on the carrier surface, ultimately enhancing the water treatment effect. For example, Chinese patent application publication number CN116514298A, publication date August 1, 2023, discloses a bacterial-algae symbiotic biofilm reactor. The bacterial-algae symbiotic biofilm reactor has multiple biofilms with bacteria and algae attached to their surfaces that can rotate around their axes. The bacteria and algae are used to reduce the nitrogen and phosphorus concentration in the water. The bacterial-algae symbiotic biofilm reactor includes a hollow cylindrical reactor body, a rotating shaft that rotatably passes through both ends of the reactor body, a motor for driving the rotating shaft, multiple supports connected to the rotating shaft, and multiple semi-flexible packing plates that support bacteria and algae and are connected to two of the supports at their respective ends. The two ends of the reactor body are respectively connected to the intermediate water storage tank and the microfiltration device. This bacterial-algae reactor has the following defects: (1) poor resistance to shock loads, making it difficult for the reactor to operate stably; (2) it adopts an external circulation method, and the rotating shaft is driven by a motor, resulting in high overall energy consumption; (3) it occupies a large area. Summary of the Invention

[0005] The present invention addresses the aforementioned problems of existing bacterial-algae symbiotic biofilm reactors and provides a bacterial-algae symbiotic biofilm reactor for treating marine aquaculture tailwater that is easy to operate, occupies a small area, consumes little energy, has good resistance to shock loads and operational stability, and has good treatment effect.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A symbiotic biofilm reactor for treating marine aquaculture wastewater comprises an outer shell, a first cylindrical partition, and a second cylindrical partition. A filtration zone is formed between the outer shell and the first cylindrical partition, and a biological filter bed is provided within the filtration zone. A flow stabilizing mechanism is provided between the first and second cylindrical partitions. A water inlet zone is formed between the flow stabilizing mechanism and the first cylindrical partition. A water inlet pipe is connected to the top of the water inlet zone. A suspended packing zone is formed between the flow stabilizing mechanism and the second cylindrical partition, and suspended packing material is provided within the suspended packing zone. An aeration device is provided at the bottom of the suspended packing zone. The water inlet zone and the suspended packing zone are connected through the flow stabilizing mechanism. The second cylindrical partition is transparent and contains a light source. A water distributor is provided above the biological filter bed. A circulation pipe is provided below the suspended packing zone, and the circulation pipe is connected to the water distributor via a water pump. An outlet pipe is connected to the outer shell located below the biological filter bed. The reactor of this invention is internally divided into different functional zones, enabling a rational allocation of aerobic and anaerobic operations. The suspended media zone, combined with aeration, is primarily used for aerobic reactions (biological contact), and most pollutants in the effluent can be treated within this zone, reducing the treatment pressure on the subsequent biological filter and preventing clogging. The biological filter in the filtration zone is mainly used for anaerobic reactions. Water from the suspended media zone is transported to the filtration zone via a circulating water pipe to complete internal circulation. Both the suspended media and the filter media surface have a structurally stable bacterial-algae symbiotic biofilm to enhance the effluent treatment effect. The effluent undergoes continuous treatment (vertical flow) through the suspended media zone and the biological filter, achieving good pollutant removal and effluent quality. The stable flow between the inlet zone and the suspended media zone... The flow mechanism connects the inlet zone and the suspended packing zone, ensuring a stable and uniform flow of water from the inlet zone into the suspended packing zone. This reduces the impact load on the suspended packing zone and improves the shock load resistance and operational stability of the invention. The inlet pipe is located at the top of the inlet zone, employing top-entry design. The resulting turbulent flow, through impact energy, fluidizes granular sludge and other organic particulate impurities, enabling them to achieve higher mass transfer and biochemical reaction rates, thereby enhancing the invention's ability to remove organic matter. Through optimized reactor structure, this invention combines the advantages of biological contact oxidation and biological filter, featuring a compact structure, small footprint, good shock load resistance and operational stability, and excellent pollutant removal efficiency and effluent quality.

[0007] Preferably, the flow stabilizing mechanism includes a third cylindrical baffle plate. The third cylindrical baffle plate has longitudinally spaced water passages along its circumference. These water passages connect the inlet area and the suspended packing area. Inlet baffles and outlet baffles are respectively provided on both sides of the inlet and outlet of the water passages. The gap between the inlet baffles forms an inlet channel, and the gap between the outlet baffles forms an outlet channel. The inlet and outlet channels have different flow directions. The water passages serve to evenly distribute water (stabilize flow), allowing the tailwater to enter the suspended packing area uniformly. The inlet and outlet baffles not only guide the flow but also change the direction of the tailwater to reduce its velocity (slow flow), avoiding direct impact on the suspended packing area. This reduces the impact load of the inlet water and improves the impact load resistance of the invention.

[0008] Preferably, the inlet and outlet channels are arranged in a "V" shape. This "V" shape arrangement is simple in structure and provides good deceleration and flow control.

[0009] Preferably, the angle between the inlet channel and the outlet channel is 40° to 80°. If the angle is too small, the resistance to the flow of tailwater will be large; if the angle is too large, the flow slowing effect will be poor. Taking all factors into consideration, the angle between the inlet channel and the outlet channel is preferably 40° to 80°.

[0010] Preferably, the aeration device includes an annular aeration pipe and an air inlet manifold, the annular aeration pipe being fixed at the bottom of the suspended packing area, and the air inlet manifold being connected to the annular aeration pipe.

[0011] Preferably, an exhaust pipe is provided at the top of the suspended packing zone. The exhaust pipe serves to release air and relieve pressure.

[0012] Preferably, the biofilter bed includes filter media and a filter media support plate. The filter media support plate is fixed within the filtration zone, and the filter media is piled on the filter media support plate. The filter media support plate is provided with filter pores. The filter media serves as a carrier for the organisms and can be selected as needed. The filter media can be crushed stone, pebbles, coke, cinder, ceramsite, plastic honeycomb, and various synthetic products, etc.

[0013] Preferably, the light source is an LED lamp or a fluorescent lamp.

[0014] Preferably, the water distributor includes an annular water distribution pipe, which is fixed above the biological filter bed. The bottom of the annular water distribution pipe is provided with a water distribution port, and the annular water distribution pipe is connected to the circulation pipe.

[0015] Therefore, the present invention has the following beneficial effects: the reactor structure has been optimized and improved, and the reactor interior is divided into different functional zones, which can realize the rational allocation of aerobic (combined with aeration) and anaerobic operations, so that it has the advantages of both biological contact oxidation and biological filter. It has a compact structure, small footprint, good resistance to shock loads and good operational stability, and can obtain better pollutant removal effect and effluent water quality. Attached Figure Description

[0016] Figure 1 This is the front view of the present invention.

[0017] Figure 2 yes Figure 1 A schematic diagram of the internal structure.

[0018] Figure 3 This is a schematic diagram showing the positional relationship between the outer shell, the first cylindrical partition, the second cylindrical partition, and the flow stabilization mechanism.

[0019] Figure 4 This is a top view of the ring-shaped water distribution pipe.

[0020] In the diagram: 1. Outer shell; 2. First cylindrical baffle; 3. Second cylindrical baffle; 4. Filtration zone; 5. Biological filter bed; 6. Flow stabilization mechanism; 7. Inlet water zone; 8. Inlet water pipe; 9. Suspended packing zone; 10. Suspended packing; 11. Aeration device; 12. Light source; 13. Water distributor; 14. Circulation pipe; 15. Water pump; 16. Outlet water pipe; 17. Third cylindrical baffle; 18. Water passage hole; 19. Inlet baffle; 20. Outlet baffle; 21. Inlet water channel; 22. Outlet water channel; 23. Annular aeration pipe; 24. Main air inlet pipe; 25. Exhaust pipe; 26. Filter media; 27. Filter media support plate; 28. Filter holes; 29. ​​Annular water distribution pipe; 30. Water distribution port. Detailed Implementation

[0021] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 , Figure 2 , Figure 3The illustrated biofilm reactor for treating mariculture wastewater includes an outer shell 1, a first cylindrical partition 2, and a second cylindrical partition 3. A filtration zone 4 is formed between the outer shell and the first cylindrical partition. A biofilter bed 5 is provided within the filtration zone, comprising filter media 26 and a filter media support plate 27. The filter media support plate is fixed within the filtration zone, and the filter media is piled on the support plate. The support plate has filter holes 28. A flow stabilizing mechanism 6 is provided between the first and second cylindrical partitions. An inlet zone 7 is formed between the flow stabilizing mechanism and the first cylindrical partition. An inlet pipe 8 is connected to the top of the inlet zone. A suspended packing zone 9 is formed between the flow stabilizing mechanism and the second cylindrical partition. An exhaust pipe 25 is provided at the top of the suspended packing zone. Suspended packing material 10 is provided within the suspended packing zone. An aeration device 11 is installed at the bottom of the suspended packing zone. The aeration device includes an annular aeration pipe 23 and an air inlet main pipe 24. The annular aeration pipe is fixed to the suspended packing. At the bottom of the packing zone, the main air inlet pipe is connected to the annular aeration pipe. The water inlet zone and the suspended packing zone are connected by a flow stabilizing mechanism. The flow stabilizing mechanism includes a third cylindrical baffle 17. The third cylindrical baffle has longitudinal water passage holes 18 spaced along its circumference. The water passage holes connect the water inlet zone and the suspended packing zone. Water inlet baffles 19 and water outlet baffles 20 are respectively provided on both sides of the inlet and outlet of the water passage holes. The gap between the water inlet baffles forms a water inlet channel 21, and the gap between the water outlet baffles forms a water outlet channel 22. The water inlet channel and the water outlet channel have different flow directions and are arranged in a "V" shape. The included angle between the water inlet channel and the water outlet channel is 80°. The second cylindrical baffle is transparent and has a light source 12 (LED lamp) inside. A water distributor 13 is provided above the biological filter bed. A circulation pipe 14 is provided at the bottom of the suspended packing zone. The circulation pipe is connected to the water distributor through a water pump 15. The water distributor includes an annular water distribution pipe 29 (e.g., Figure 4 As shown), the annular water distribution pipe is fixed above the biological filter bed. The bottom of the annular water distribution pipe is provided with a water distribution port 30. The annular water distribution pipe is connected to the circulation pipe. The outer shell located below the biological filter bed is connected to the water outlet pipe 16.

[0023] The operating principle of this invention is as follows: the effluent is transported to the inlet area through the inlet pipe, and after being decelerated and redistributed by the flow stabilization mechanism, it enters the suspended packing area. The aeration device performs bottom aeration, and the suspended packing is in full contact with the effluent to carry out aerobic reaction. The effluent after aerobic reaction in the suspended packing area is transported to the filtration area by a water pump. After being filtered and anaerobic reacted by the biological filter bed, it is discharged from the outlet pipe.

[0024] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. A biofilm reactor for treating mariculture wastewater, characterized in that, The system includes an outer shell (1), a first cylindrical partition (2), and a second cylindrical partition (3). A filtration zone (4) is formed between the outer shell and the first cylindrical partition. A biological filter bed (5) is provided in the filtration zone. A flow stabilizing mechanism (6) is provided between the first cylindrical partition and the second cylindrical partition. An inlet zone (7) is formed between the flow stabilizing mechanism and the first cylindrical partition. An inlet pipe (8) is connected to the top of the inlet zone. A suspended packing zone (9) is formed between the flow stabilizing mechanism and the second cylindrical partition. Suspended packing material (10) is provided in the suspended packing zone. An aeration device (11) is provided at the bottom of the suspended packing zone. The inlet zone and the suspended packing zone are connected by the flow stabilizing mechanism. The second cylindrical partition is transparent and has a light source inside. Source (12), a water distributor (13) is provided above the biological filter bed, a circulation pipe (14) is provided below the suspended packing area, the circulation pipe is connected to the water distributor through a water pump (15), and an outlet pipe (16) is connected to the outer shell located below the biological filter bed; the flow stabilizing mechanism includes a third cylindrical baffle (17), the third cylindrical baffle is provided with longitudinal water passage holes (18) spaced along the circumference, the water passage holes connect the water inlet area and the suspended packing area, the inlet and outlet sides of the water passage holes are respectively provided with inlet baffles (19) and outlet baffles (20), the gap between the inlet baffles forms an inlet channel (21), the gap between the outlet baffles forms an outlet channel (22), the inlet channel and the outlet channel have different flow directions.

2. The biofilm reactor for treating marine aquaculture wastewater according to claim 1, characterized in that, The water inlet and outlet channels are arranged in a "V" shape.

3. The algae-bacterial symbiotic biofilm reactor for treating marine aquaculture tailwater according to claim 2, characterized in that, The included angle between the water inlet channel and the water outlet channel is 40°~80°.

4. The algae-bacterial symbiotic biofilm reactor for treating marine aquaculture tailwater according to claim 1, characterized in that, The aeration device includes an annular aeration pipe (23) and an air inlet manifold (24). The annular aeration pipe is fixed at the bottom of the suspended packing area, and the air inlet manifold is connected to the annular aeration pipe.

5. A biofilm reactor for treating marine aquaculture tailwater according to claim 1, characterized in that, An exhaust pipe (25) is provided at the top of the suspended packing area.

6. A biofilm reactor for treating marine aquaculture tailwater according to claim 1, characterized in that, The biofilter bed includes filter media (26) and filter media support plate (27). The filter media support plate is fixed in the filtration zone, the filter media is piled on the filter media support plate, and the filter media support plate is provided with filter holes (28).

7. A biofilm reactor for treating marine aquaculture wastewater according to claim 1, characterized in that, The light source is an LED lamp or a fluorescent lamp.

8. A biofilm reactor for treating marine aquaculture tailwater according to claim 1, characterized in that, The water distributor includes an annular water distribution pipe (29), which is fixed above the biological filter bed. A water distribution port (30) is provided at the bottom of the annular water distribution pipe, and the annular water distribution pipe is connected to the circulation pipe.

Images