A device for efficiently cultivating microalgae in a circulating water system

Abstract

The present invention relates to the technical field of microalgae cultivation, and in particular to a circulating water system efficient microalgae cultivation device, comprising an electrocatalytic reactor for treating harmful substances in aquaculture tail water, and a breeding raceway pool for expanding the cultivation of microalgae, a biological treatment unit for preliminary cultivation of microalgae is arranged on one side of the electrocatalytic reactor, and the biological treatment unit comprises a bioreactor 1, a bioreactor 2 and a bioreactor 3 arranged in sequence, and the cross section of the bioreactor 1 is set to be conical and made of plastic. The present invention can achieve the degradation of harmful substances in aquaculture wastewater, and then use the degraded tail water to cultivate microalgae, thereby realizing the recycling of nutrients, which can not only stabilize the aquaculture water quality, but also form a closed-loop circulation of aquaculture water, avoiding the situation where the tolerance of microalgae to high concentrations of harmful substances is limited due to the complex types of pollutants in the aquaculture tail water, thereby affecting its normal growth and purification efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of microalgae cultivation, and in particular to a device for efficiently cultivating microalgae in a circulating water system. Background Art

[0002] The existing factory aquaculture system, due to its high-density production characteristics, has increased production while also bringing about problems such as water quality deterioration, tailwater pollution and waste of water resources. Aquaculture wastewater usually contains a large amount of harmful substances such as organic matter, ammonia nitrogen, and phosphate. Microalgae can absorb nutrients such as nitrogen and phosphorus in aquaculture wastewater through photosynthesis, and achieve the degradation of pollutants and water purification. It can also be used as high-value-added resources such as feed and fertilizer. However, in actual applications, due to the high concentration of harmful substances in aquaculture tailwater, the growth of microalgae is easily inhibited. Microalgae has limited tolerance to high concentrations of harmful substances, which affects its normal growth and purification efficiency. At the same time, there are still many technical bottlenecks in the design of microalgae cultivation systems and the recycling of tailwater, which cannot achieve complete purification of water quality. Aquaculture tailwater is mostly discharged, resulting in waste of water resources. Summary of the invention

[0003] In order to overcome the shortcomings of the prior art, the present invention provides a device for efficiently cultivating microalgae in a circulating water system, which solves the problem that the cultivation of microalgae in the prior art is easily inhibited, thus affecting its normal growth and purification efficiency.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] A circulating water system high-efficiency microalgae cultivation device comprises an electrocatalytic reactor for treating harmful substances in aquaculture tail water, and a breeding raceway pool for expanding the cultivation of microalgae. A biological treatment unit for preliminary cultivation of microalgae is arranged on one side of the electrocatalytic reactor. The biological treatment unit comprises bioreactor one, bioreactor two and bioreactor three arranged in sequence. The cross section of bioreactor one is arranged to be conical and made of plastic, the cross section of bioreactor two is arranged to be columnar and made of acrylic material, and bioreactor three is arranged to be packed in a plastic bag and made of polyethylene material. A wire mesh bucket for stabilizing the shape of the plastic bag is also arranged on the outside of bioreactor three.

[0006] As a further optimization scheme of the present invention, a breeding pond for providing ecological circulating water is arranged at one end of the breeding runway pond, a pumping pipe 1 with a water outlet in the breeding pond is arranged at one end of the breeding runway pond, a water pump located in the breeding runway pond is arranged at the water inlet of the pumping pipe 1, a disc centrifuge for separating microalgae cells from water is arranged on one side of the breeding pond, a pumping pipe 2 is installed at the water inlet end of the disc centrifuge, and a water pump located in the breeding runway pond is also arranged at the water inlet of the pumping pipe 2.

[0007] As a further optimization scheme of the present invention, the bottom of the culture pond is also fixedly connected to a discharge pipe 1, and the top side of the electrocatalytic reactor is fixedly installed with an inlet pipe 1 connected to the discharge pipe 1 through a sealing flange.

[0008] As a further optimization scheme of the present invention, the water outlet end of the disc centrifuge is fixedly connected to the second discharge pipe through a sealing flange, and the other side of the top of the electrocatalytic reactor is fixedly installed with a second water inlet pipe connected to the second discharge pipe through a sealing flange.

[0009] As a further optimization scheme of the present invention, the bottom of the electrocatalytic reactor is fixedly connected to a main PVC pipe, the inner sides of the bioreactor 1, bioreactor 2 and bioreactor 3 are respectively provided with aeration devices for increasing the dissolved oxygen in the water to ensure that the microalgae have sufficient oxygen supply, and the tops of the bioreactor 1, bioreactor 2 and bioreactor 3 are respectively fixedly connected to secondary PVC pipes connected to the main PVC pipe.

[0010] As a further optimization scheme of the present invention, the bottom ends of bioreactor 1, bioreactor 2 and bioreactor 3 are respectively fixedly connected with drainage pipes, and the outlets of the drainage pipes are located at the top of the breeding track pool. A water wheel is provided on the breeding track pool to improve water fluidity and increase water exchange.

[0011] By means of the above technical solution, the present invention provides a device for efficiently cultivating microalgae in a circulating water system, which has at least the following beneficial effects compared with the prior art:

[0012] 1. The present invention treats the aquaculture tail water by an electrocatalytic reactor first, and then combines it with a biological treatment unit to efficiently cultivate microalgae, so as to achieve the degradation of harmful substances in the aquaculture wastewater, and then use the degraded tail water to cultivate microalgae, thereby realizing the recycling of nutrients. It can not only stabilize the aquaculture water quality, but also form a closed-loop circulation of aquaculture water, avoiding the situation that the tolerance of microalgae to high concentrations of harmful substances is limited due to the complex types of pollutants in the aquaculture tail water, which affects its normal growth and purification efficiency.

[0013] 2. The present invention achieves the purpose of resource processing by setting up a resource recovery unit to harvest and utilize microalgae biomass, avoiding the situation where traditional water treatment methods cannot achieve thorough water purification, and aquaculture tail water is mostly discharged, resulting in waste of water resources. It improves the utilization rate of water circulation and solves the technical problem of resource utilization in factory aquaculture tail water treatment.

[0014] 3. The present invention separates microalgae cells from water by setting up a disc centrifuge, and the remaining supernatant can be returned to the electrocatalytic reactor for treatment before cultivating microalgae, thereby achieving efficient synergy and closed-loop operation, making resource utilization more sufficient and significantly improving water resource utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0017] Figure 2 It is a front structural schematic diagram of the present invention;

[0018] Figure 3 It is a schematic diagram of the structure of the biological treatment unit of the present invention.

[0019] In the figure: 1. Electrocatalytic reactor; 2. Aquaculture raceway pool;

[0020] 3. Biological treatment unit; 31. Bioreactor 1; 32. Bioreactor 2; 33. Bioreactor 3; 34. Wire mesh bucket; 35. Main PVC pipe; 36. Secondary PVC pipe; 37. Drainage pipe; 38. Water truck;

[0021] 4. Breeding pond; 5. Suction pipe 1; 6. Disc centrifuge; 7. Suction pipe 2; 8. Discharge pipe 1; 9. Inlet pipe 1; 10. Discharge pipe 2; 11. Inlet pipe 2. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] First embodiment

[0024] The current factory aquaculture system produces a large amount of aquaculture wastewater, which usually needs to be purified before discharge. At the same time, it has been found that microalgae can absorb nutrients such as nitrogen and phosphorus in aquaculture wastewater, and achieve pollutant degradation and water purification. However, due to the high concentration of harmful substances in aquaculture tail water, the growth of microalgae is easily inhibited, affecting its normal growth and purification efficiency. In order to degrade the concentration of harmful substances in aquaculture tail water and improve the purification efficiency of microalgae for harmful substances, Figure 1 - Figure 3 This embodiment provides a circulating water system efficient microalgae cultivation device, including an electrocatalytic reactor 1 for treating harmful substances in aquaculture tail water and a breeding raceway pool 2 for expanding the cultivation of microalgae.

[0025] The electrocatalytic reactor 1 uses the principle of electrocatalytic reaction to promote chemical reactions by driving the catalyst through electric current, which can effectively remove harmful substances in aquaculture tail water, such as ammonia nitrogen NH3-N, nitrate NO3 - 、Nitrite NO2 - , organic matter, heavy metal ions, etc. The electrocatalytic reaction can effectively decompose these pollutants to prevent these substances from polluting the water quality and affecting the ecological balance of the water body; the microalgae in the breeding track pool 2 absorb carbon dioxide CO2, nitrogen, phosphorus and other nutrients in the water through photosynthesis, and convert them into their own biomass, which can effectively remove harmful substances in the water, especially nutrients such as nitrogen and phosphorus, which helps to reduce the risk of eutrophication of water bodies; and the microalgae can also absorb organic matter and toxic chemicals in the tail water to reduce water pollution.

[0026] In order to optimize the growth environment of microalgae and improve the overall yield of microalgae, a biological treatment unit 3 for preliminary cultivation of microalgae is arranged on one side of the electrocatalytic reactor 1. The biological treatment unit 3 includes a bioreactor 1 31, a bioreactor 2 32 and a bioreactor 3 33 arranged in sequence. The cross-section of the bioreactor 1 31 is set to be conical and made of plastic, the cross-section of the bioreactor 2 32 is set to be columnar and made of acrylic material, and the bioreactor 3 33 is set to be packed in a plastic bag and made of polyethylene material. The use of multiple bioreactors can regulate different culture conditions such as light, temperature, pH value, dissolved oxygen content, etc. in different reactors, and multiple reactors make it possible to simultaneously cultivate microalgae under different conditions to obtain microalgae at different growth stages, which is conducive to achieving efficient biomass accumulation.

[0027] A wire mesh bucket 34 is also provided on the outside of the bioreactor 33 to stabilize the shape of the plastic bag. The plastic bag itself is a soft and easily deformable material. When culturing microalgae in the bioreactor, the bag may be deformed or damaged due to factors such as internal and external pressure difference, liquid flow, gas transmission, etc. The wire mesh bucket 34 can provide external support to prevent the bag from being squeezed, collided or overstretched and thus causing rupture, thereby increasing the stability and durability of the system;

[0028] The bottom of the electrocatalytic reactor 1 is fixedly connected with a main PVC pipe 35, and the inner sides of the bioreactor 1 31, the bioreactor 2 32 and the bioreactor 3 33 are respectively provided with aeration devices 36, and the tops of the bioreactor 1 31, the bioreactor 2 32 and the bioreactor 3 33 are respectively fixedly connected with secondary PVC pipes 36 connected with the main PVC pipe 35. The treated water in the electrocatalytic reactor 1 flows into the bioreactor 1 31, the bioreactor 2 32 and the bioreactor 3 33 through the main PVC pipe 35. At the same time, microalgae are cultured in the bioreactor 1 31, the bioreactor 2 32 and the bioreactor 3 33, respectively, and the aeration device 36 is used to increase the dissolved oxygen in the water to ensure that the microalgae have sufficient oxygen supply to promote their growth and reproduction.

[0029] The bottom ends of bioreactor 1 31, bioreactor 2 32 and bioreactor 3 33 are respectively fixedly connected with drainage pipes 37, and the outlets of drainage pipes 37 are located at the top of breeding track pool 2. The water in bioreactor 1 31, bioreactor 2 32 and bioreactor 3 33 can be discharged into breeding track pool 2 through the drainage pipes 37 at the bottom thereof to continue the cultivation of microalgae. A water wheel 38 is arranged on breeding track pool 2. Since the growth of microalgae requires a relatively uniform water flow and nutrient distribution to ensure that the algae in each area can obtain sufficient light and nutrients, the water wheel 38 promotes the circulation of water in the pool by continuously pushing the water flow, avoiding uneven distribution of algae due to sedimentation or stagnation of water. The uniform water flow can better distribute the microalgae in the pool, ensure the consistency of the growth environment, and improve the growth efficiency.

[0030] Second embodiment

[0031] The water treated by the biological treatment unit 3 can be directly pumped into the aquaculture pond 4 for aquaculture. Figure 1 - Figure 2 The specific implementation method is that a breeding pool 4 for providing ecological circulating water is arranged at one end of the breeding track pool 2, a water pumping pipe 5 with a water outlet in the breeding pool 4 is arranged at one end of the breeding track pool 2, and a water pump located in the breeding track pool 2 is arranged at the water inlet of the water pumping pipe 5. The bottom of the breeding pool 4 is also fixedly connected with a discharge pipe 8, and a water inlet pipe 9 connected with the discharge pipe 8 through a sealing flange is fixedly installed on one side of the top of the electrocatalytic reactor 1. After a period of breeding, the breeding tail water in the breeding pool 4 can be passed through the discharge pipe 8 and the water inlet pipe 9 and introduced into the electrocatalytic reactor 1 for treatment and recycling.

[0032] A disc centrifuge 6 for separating microalgae cells from water is provided on one side of the culture pond 4, a pumping pipe 2 7 is installed at the water inlet end of the disc centrifuge 6, and a water pump located in the culture raceway pond 2 is also provided at the water inlet of the pumping pipe 2 7. The water outlet end of the disc centrifuge 6 is fixedly connected to a discharge pipe 2 10 through a sealing flange, and an inlet pipe 2 11 connected to the discharge pipe 2 10 through a sealing flange is fixedly installed on the other side of the top of the electrocatalytic reactor 1. When the water supply in the culture pond 4 is sufficient, the water body and microalgae of the culture raceway pond 2 are simultaneously pumped into the disc centrifuge 6 through the pumping pipe 2 7, and the disc centrifuge 6 separates the microalgae liquid, and the obtained supernatant is passed into the electrocatalytic reactor 1 through the discharge pipe 2 10 and the inlet pipe 2 11 for treatment and recycling.

[0033] The present invention first treats the aquaculture tail water through the electrocatalytic reactor 1, and then combines the biological treatment unit 3 to efficiently cultivate microalgae, so as to achieve the degradation of harmful substances in the aquaculture wastewater, and then use the degraded tail water to cultivate microalgae. The harmful substances in the aquaculture tail water will be thoroughly purified by the biological treatment unit 3. The purified water body can continue to be used for aquaculture, and the microalgae liquid can also be separated to achieve the recycling of nutrients. It can not only stabilize the aquaculture water quality, but also form a closed-loop circulation of aquaculture water. In this mode, the microalgae culture in each reactor does not need to add any other substances. It all depends on the nutrients in the circulating water and natural conditions such as light, and the microalgae can reach biological growth without any treatment.

[0034] During use of the microalgae cultivation device, the aquaculture tail water generated in the aquaculture pond 4 is discharged into the electrocatalytic reactor 1 through the discharge pipe 1 8 and the water inlet pipe 1 9. The electrocatalytic reactor 1 utilizes the principle of electrocatalytic reaction to promote chemical reaction by driving the catalyst through electric current, and can efficiently remove harmful substances in the aquaculture tail water. Then, the water treated in the electrocatalytic reactor 1 flows into the bioreactor 1 31, the bioreactor 2 32 and the bioreactor 3 33 through the main PVC pipe 35, and the microalgae are cultivated in the bioreactor 1 31, the bioreactor 2 32 and the bioreactor 3 33 respectively. After cultivating the microalgae for a period of time, the water in the bioreactor 1 31, the bioreactor 2 32 and the bioreactor 3 33 can be discharged into the aquaculture runway pool 2 through the drainage pipe 37 at the bottom thereof to continue the cultivation of the microalgae and the thorough purification of the water. The purified water can be directly extracted into the aquaculture pond 4 for aquaculture use, forming a circulation process.

[0035] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0036] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A circulating water system high-efficiency microalgae cultivation device, comprising an electrocatalytic reactor (1) for treating harmful substances in aquaculture tail water, and a breeding raceway pool (2) for expanding the cultivation of microalgae, characterized in that: A biological treatment unit (3) for preliminary cultivation of microalgae is provided on one side of the electrocatalytic reactor (1); The biological treatment unit (3) comprises a bioreactor 1 (31), a bioreactor 2 (32) and a bioreactor 3 (33) which are arranged in sequence, wherein the cross section of the bioreactor 1 (31) is arranged to be conical and made of plastic, the cross section of the bioreactor 2 (32) is arranged to be columnar and made of acrylic material, and the bioreactor 3 (33) is arranged to be packed in a plastic bag and made of polyethylene material, and a wire mesh bucket (34) for stabilizing the shape of the plastic bag is also arranged on the outside of the bioreactor 3 (33).

2. The device for efficiently cultivating microalgae in a circulating water system according to claim 1, characterized in that: A breeding pool (4) for providing ecological circulating water is arranged at one end of the breeding raceway pool (2); a water pumping pipe (5) with a water outlet in the breeding pool (4) is arranged at one end of the breeding raceway pool (2); a water pump located in the breeding raceway pool (2) is arranged at the water inlet of the water pumping pipe (5).

3. The device for efficiently cultivating microalgae in a circulating water system according to claim 2, characterized in that: A disc centrifuge (6) for separating microalgae cells from water is arranged on one side of the culture pond (4), a second water pump (7) is installed at the water inlet end of the disc centrifuge (6), and a water pump located in the culture raceway pond (2) is also arranged at the water inlet of the second water pump (7).

4. The device for efficiently cultivating microalgae in a circulating water system according to claim 2, characterized in that: The bottom of the culture pond (4) is also fixedly connected to a discharge pipe (8), and a water inlet pipe (9) connected to the discharge pipe (8) via a sealing flange is fixedly installed on one side of the top of the electrocatalytic reactor (1).

5. The device for efficiently cultivating microalgae in a circulating water system according to claim 3, characterized in that: The water outlet end of the disc centrifuge (6) is fixedly connected to a second discharge pipe (10) via a sealing flange, and a second water inlet pipe (11) connected to the second discharge pipe (10) via a sealing flange is fixedly installed on the other side of the top of the electrocatalytic reactor (1).

6. The device for efficiently cultivating microalgae in a circulating water system according to claim 1, characterized in that: The bottom of the electrocatalytic reactor (1) is fixedly connected to a main PVC pipe (35), and the inner sides of the bioreactor 1 (31), the bioreactor 2 (32) and the bioreactor 3 (33) are respectively provided with aeration devices for increasing the dissolved oxygen in the water to ensure that the microalgae have sufficient oxygen supply.

7. The device for efficiently cultivating microalgae in a circulating water system according to claim 1, characterized in that: The tops of the bioreactor 1 (31), the bioreactor 2 (32) and the bioreactor 3 (33) are respectively fixedly connected with secondary PVC pipes (36) connected to the main PVC pipe (35).

8. The device for efficiently cultivating microalgae in a circulating water system according to claim 1, characterized in that: The bottom ends of the bioreactor 1 (31), the bioreactor 2 (32) and the bioreactor 3 (33) are respectively fixedly connected to drainage pipes (37), and the water outlets of the drainage pipes (37) are located at the top of the breeding raceway pool (2). A water wheel (38) for improving water fluidity and increasing water exchange is arranged on the breeding raceway pool (2).

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