An automated wastewater discharge polysaccharide unicellular algae propagation system and its usage method

Abstract

This invention provides an automated wastewater discharge system for the cultivation of polysaccharide-containing single-celled algae and its usage method, relating to the field of microbiological device technology. It includes a translucent circular cultivation cylinder with a central wastewater discharge port at the bottom and an overflow port at the top. Multiple aeration nozzles are arranged in a ring within the cylinder, rotating clockwise or counterclockwise along the cylinder wall to drive the culture medium within the cylinder to form a rotating flow field. The cultivation system also includes a water injection pipe, a replenishment pipe, a wastewater discharge pipe, and a ring-shaped supplemental lighting system. This system creates a rotating flow field through bottom ring aeration, completely eliminating stagnant water zones and ensuring uniform suspension of algal cells. The rotating water flow automatically collects aging algal cells and surface foam, which are then quickly discharged through the central wastewater discharge pipe. It is equipped with a self-cleaning supplemental lighting system, ensuring continuous and sufficient light conditions. It supports individual use and multiple units connected in parallel to form a mother-daughter tank mode, significantly improving the efficiency and stability of industrial production.

Description

Technical Field

[0001] This invention relates to the field of microbiological equipment technology, and in particular to an automated wastewater discharge polysaccharide unicellular algae propagation system and its usage method. Background Technology

[0002] Polysaccharide-producing unicellular algae are a type of single-celled microalgae capable of synthesizing and accumulating polysaccharides. They are microorganisms widely used in aquaculture seedling feed and bioactive substance extraction. Large-scale cultivation often employs a stepped scale-up process, with open raceway tanks frequently used in the final production-level expansion stage. While raceway tanks offer advantages such as low cost and ease of construction, they also have significant drawbacks: raceway tanks typically rely on impellers to drive water circulation, but due to uneven flow field distribution, "dead water zones" or low-velocity zones easily form at tank corners, edges, and the center of the tank bottom. Aged, dead, or polysaccharide-secreting algal cells struggle to maintain suspension, gradually settling to the bottom or attaching to the tank walls, forming difficult-to-remove biofilms and sediment layers. Furthermore, to increase propagation speed, supplemental lighting is usually added to the water, but unicellular algae are phototactic, and dead algae will attach to the lighting tubes. These sediments decompose under anaerobic conditions, consuming large amounts of dissolved oxygen in the water and releasing toxic metabolites such as hydrogen sulfide. This not only inhibits the growth of healthy algal cells but also accelerates their death, fostering the growth of bacteria, fungi, and other pollutants, creating a vicious cycle. In severe cases, it can lead to the complete death of all algae, resulting in a zero harvest. Therefore, after each batch of algae propagates, every corner needs to be manually cleaned, which is time-consuming, labor-intensive, and inefficient, resulting in poor pit contamination and a high risk of total crop failure. Summary of the Invention

[0003] This invention addresses the technical problems associated with raceway pond cultivation of polysaccharide-containing monocellular algae by providing an automated wastewater discharge system and its usage method. The system utilizes bottom-ring aeration to create a rotating flow field, completely eliminating stagnant water zones and ensuring uniform suspension of algal cells. The rotating water flow automatically gathers and quickly discharges aged algal cells and surface foam. Equipped with a self-cleaning supplemental lighting system, it ensures continuous and sufficient light conditions, reducing algal mortality. It supports individual use and multiple units connected in parallel in a mother-daughter pond mode, enabling continuous, unmanned, and automated cultivation, significantly improving the efficiency and stability of industrial production.

[0004] Therefore, the technical solution of the present invention is an automatic sewage discharge polysaccharide unicellular algae propagation system, comprising a light-transmitting circular cultivation tube with a central sewage outlet at the bottom and an overflow outlet at the top; multiple aeration nozzles arranged in a ring inside the cultivation tube, connected to an aeration pump via aeration pipes, and arranged clockwise or counterclockwise along the tube wall to drive the culture medium inside the cultivation tube to form a rotating flow field; the propagation system also includes a water injection pipe, a replenishment pipe, a sewage discharge pipe, and a ring-shaped supplemental light. The water injection pipe is used to inject culture water, the replenishment pipe is used to inject nutrient solution, the sewage discharge pipe is connected to the sewage outlet at the bottom of the cultivation tube to discharge aging or dead algal cells and surface foam, and the ring-shaped supplemental light is used to provide sufficient light for the propagation system. The counterclockwise rotation of the culture medium drives the algae-cleaning component on the supplemental light to slide counterclockwise, and the clockwise rotation drives the algae-cleaning component on the supplemental light to slide counterclockwise. The alternating flow of the culture medium in both directions automatically cleans the supplemental light.

[0005] Furthermore, the bottom of the aquaculture tank has a downward-concave curved structure to facilitate the collection of sediment towards the central sewage outlet.

[0006] Furthermore, the water injection pipe is equipped with a water injection valve or a water injection pump, the replenishment pipe is equipped with a replenishment valve or a replenishment pump, and the drain pipe is equipped with a drain valve or a drain pump.

[0007] Furthermore, the water injection valve, replenishment valve, and drain valve are either manual or automatic valves.

[0008] Furthermore, there are multiple ring lights, which are arranged in concentric circles at intervals.

[0009] Furthermore, the spacing between adjacent ring lights is 50-60 centimeters.

[0010] Furthermore, the bottom of the aquaculture tank is equipped with a heating water pipe or an electric heating pipe.

[0011] Furthermore, the supplementary light is equipped with an algae-removing component, which includes an algae-removing block fitted onto the lamp tube and an algae-removing pusher plate connected to the outside of the algae-removing block. The algae-removing block is one of sponge, silicone, brush, or foamed plastic.

[0012] A method for using an automated wastewater discharge polysaccharide-monocytic algae propagation system includes the following steps: Multiple propagation systems are connected in parallel, with one serving as the mother tank and the others as daughter tanks; algae are inoculated and cultivated in the mother tank; when the algal solution in the mother tank reaches a set density, a portion of the algal solution is diverted to one daughter tank through an overflow outlet or a pipe with a valve, and cultivation water and nutrient solution are added to that daughter tank; thereafter, algal solution is diverted to other daughter tanks sequentially at set intervals; after the algal solution in the daughter tank reaches a harvesting density, harvesting is carried out sequentially, and algal solution is replenished from the mother tank to the daughter tank after harvesting, thereby achieving initial continuous, step-by-step propagation production; or, when multiple propagation systems have reached a set density of mature algal solution, automatic propagation and harvesting are achieved simultaneously with the addition of nutrient solution for shellfish feeding, realizing continuous propagation, harvesting, and feeding without cleaning.

[0013] Furthermore, the set interval time depends on the number of propagation systems used and the algal growth cycle.

[0014] The beneficial effects of this invention are that the expansion cultivation system, by setting arc-shaped aeration nozzles in a ring at the bottom of the circular cultivation tank, drives the culture medium to form a stable and uniform rotating flow field, completely eliminating the "dead water zone" in traditional cultivation methods and ensuring good suspension and uniform distribution of algal cells. The rotating water flow can naturally collect the settled aging algal cells to the drain outlet at the center of the bottom of the tank, while simultaneously gathering the foam on the water surface at the center. Rapid automatic drainage can be completed in just 3-5 minutes, and the discharged algal residue can be directly used as aquatic feed, realizing resource utilization. This process removes metabolic waste in a timely manner, effectively preventing biofilm formation and water quality deterioration, and providing a stable environment for the healthy growth of algae.

[0015] The system employs concentrically distributed supplemental lighting, allowing for flexible spectral configuration based on the specific needs of different algae species. It also features water-driven algae-cleaning components that automatically remove attached algae film from the lamp surfaces, ensuring continuous and sufficient illumination. The system's alternating flow of the culture medium in both directions automatically cleans the supplemental lighting. This system can operate independently or multiple systems can be connected in parallel in a "mother-daughter tank" configuration, supporting stepped, continuous, and automated expansion cultivation. This significantly improves the efficiency of industrial production and the overall system stability, making it ideal for large-scale microalgae cultivation. Attached Figure Description

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

[0017] Figure 2 yes Figure 1 Another structural diagram;

[0018] Figure 3 yes Figure 1 The main view;

[0019] Figure 4 yes Figure 1 Top view;

[0020] Figure 5 This is a schematic diagram of the aquaculture tank structure;

[0021] Figure 6 This is a structural diagram of a drain pipe or a liquid replenishment pipe;

[0022] Figure 7 This is a schematic diagram of the aeration mechanism;

[0023] Figure 8 This is a structural diagram of the sewage pipe;

[0024] Figure 9 This is a schematic diagram of the supplementary lighting mechanism;

[0025] Figure 10 This is a schematic diagram of the algae removal component;

[0026] Figure 11 This is a schematic diagram of the structure of the breeding tank and the heating tube.

[0027] Explanation of symbols in the diagram:

[0028] 1. Culture tank; 11. Overflow outlet; 12. Sewage outlet; 2. Water injection pipe; 21. Water injection valve; 22. Water injection pump; 3. Liquid replenishment pipe; 31. Liquid replenishment valve; 32. Liquid replenishment pump; 4. Aeration mechanism; 41. Aeration nozzle; 42. Aeration pipe; 43. Aeration pump; 5. Sewage discharge pipe; 51. Sewage discharge valve; 52. Sewage discharge pump; 6. Lighting mechanism; 61. Lighting frame; 62. Lighting lamp; 63. Hanging rod; 7. Algae cleaning component; 71. Algae cleaning block; 72. Algae cleaning push plate; 8. Heating water pipe. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] like Figures 1-9As shown, the present invention provides an automatic sewage discharge polysaccharide unicellular algae propagation system. The propagation system includes a cultivation cylinder 1 and a water injection pipe 2, a liquid replenishment pipe 3, an aeration mechanism 4, a sewage discharge pipe 5, and a lighting mechanism 6 installed on the cultivation cylinder 1. The cultivation cylinder 1 is a light-transmitting circular cylinder. Since polysaccharide unicellular algae require sufficient light for growth, using a light-transmitting cultivation cylinder can increase the light intensity of the propagation system. An overflow port 11 is provided at the upper end of the cylinder wall of the cultivation cylinder 1, and a sewage discharge port 12 is provided in the middle of the bottom of the cultivation cylinder 1. The overflow port 11 is used for the discharge of algal liquid, and the sewage discharge port 12 is used for the discharge of foam formed by aging and dead algal cells and algal vesicles. In order to facilitate the collection of aging and dead algal cells, the bottom of the cultivation cylinder 1 is provided with a concave surface facing downwards.

[0031] Water injection pipe 2 is used to inject culture water into culture tank 1. One end of water injection pipe 2 is connected to culture tank 1, and the other end of water injection pipe 2 is connected to the storage device for culture water. The culture water is derived from treated natural seawater or artificially prepared seawater. For example, natural seawater needs to be filtered by sand, activated carbon, and disinfected by ultraviolet light or ozone to remove algae, zooplankton and pathogenic microorganisms. Artificial seawater is prepared with fresh water and sea salt according to a standard formula (such as f / 2 culture medium base) to ensure stable ionic composition.

[0032] The water injection pipe 2 is equipped with a water injection valve 21 and a water injection pump 22. The water injection valve 21 is a manual valve or an automatic valve. The water injection valve 21 controls the opening or closing of the water injection pipe 2. The water injection pump 22 is used to provide power to the water injection pipe 2. The water injection pump 22 can adjust the flow rate of the culture water in the water injection pipe 2, that is, the water injection pump 22 controls the amount of culture water injected into the culture tank 1 per unit time.

[0033] The replenishment tube 3 is used to inject nutrient solution into the culture tank 1. One end of the replenishment tube 3 is connected to the culture tank 1, and the other end of the replenishment tube 3 is connected to the nutrient solution storage device. The nutrient solution is an artificially prepared culture medium solution that provides essential nutrients for the growth of microalgae. Its core function is to supplement key components such as nitrogen, phosphorus, trace elements, and vitamins to support efficient photosynthesis, cell division, and polysaccharide accumulation of microalgae.

[0034] The replenishment pipe 3 is equipped with a replenishment valve 31 and a replenishment pump 32. The replenishment valve 31 is a manual valve or an automatic valve. The replenishment valve 31 controls the opening or closing of the replenishment pipe 3. The replenishment pump 32 is used to provide power to the replenishment pipe 3. The replenishment pump 32 can adjust the flow rate of nutrient solution in the replenishment pipe 3, that is, control the amount of nutrient solution injected into the breeding tank 1 per unit time.

[0035] The aeration mechanism 4 includes an aeration nozzle 41, an aeration pipe 42, and an aeration pump 43. The aeration nozzle 41 is installed at the bottom of the aquaculture tank 1. There are multiple aeration nozzles 41. As the optimal solution, there are four aeration nozzles 41. The shape of the aeration nozzle 41 is designed to be arc-shaped so that it matches the shape of the tank wall of the aquaculture tank 1. The aeration nozzles 41 are fixed on the tank wall of the aquaculture tank 1. The multiple aeration nozzles 41 are distributed in a ring at intervals along the tank wall of the aquaculture tank 1, and the air outlet direction of the multiple aeration nozzles 41 is distributed clockwise along the tank wall of the aquaculture tank 1.

[0036] The aeration pipe 42 is used to connect multiple aeration nozzles 41 to the aeration pump 43. The aeration pump 43 introduces air into the culture tank 1 and provides power for the rotation of the culture water in the culture tank 1. The culture water in the culture tank 1 rotates clockwise under the push of the air sprayed from the aeration nozzles 41. The rotation speed of the culture water in the culture tank 1 can be adjusted by the aeration pump 43, for example, by controlling it to 15-20 mm / s.

[0037] The rotating flow of the culture water within culture tank 1 creates and maintains a uniform, stable, and suitable environment for algal growth. Its functions are twofold: first, it prevents algal cells from settling and keeps them suspended: Polysaccharide-containing unicellular algae are tiny and would gradually sink to the bottom in still water due to gravity. The rotating flow ensures that all algal cells are uniformly suspended in the culture water, allowing each cell to have equal access to light and nutrients; second, it promotes the uniform mixing of nutrients and gases: the rotating flow rapidly disperses the added nutrient solution (nitrogen, phosphorus, etc.) and the introduced air (or carbon dioxide) throughout the entire culture system, preventing localized nutrient depletion or gas accumulation. Simultaneously, it also facilitates the metabolism of algae. The products (such as oxygen) are evenly diffused to prevent local accumulation and growth inhibition; thirdly, it prevents algal cells from adhering to the wall of the aquaculture tank 1: multiple aeration nozzles 41 are distributed in a ring at intervals along the wall of the aquaculture tank 1, and the water flow velocity is greater closer to the wall in the aquaculture tank 1, which can prevent algal cells from adhering to the wall of the aquaculture tank 1; fourthly, it rotates and gathers the aging and dead algal cells in the middle of the bottom of the aquaculture tank 1, and rotates and gathers the foam formed by algal veil in the middle of the water surface of the aquaculture tank 1, so as to facilitate the discharge of the aging and dead algal cells and the foam formed by algal veil through the sewage pipe 5. The discharged aging and dead algal cells can be directly used as feed for aquatic seedlings.

[0038] The sewage pipe 5 is used to discharge foam formed by aging and dead algal cells and algal vegetation. The starting end of the sewage pipe 5 is installed on the sewage outlet 12 in the middle of the bottom of the aquaculture tank 1. The sewage pipe 5 is equipped with a sewage valve 51 and a sewage pump 52. The sewage valve 51 is a manual valve or an automatic valve. The opening or closing of the sewage pipe 5 is controlled by the sewage valve 51. The sewage pump 52 is used to provide power to the sewage pipe 5 to discharge aging and dead algal cells into aquaculture seedling ponds, such as oyster ponds.

[0039] When the drain valve 51 of the drain pipe 5 is opened, the culture water in the culture tank 1 will be discharged through the drain pipe 5. At the same time, the aging and dead algal cells that have accumulated in the middle of the bottom of the culture tank 1 will be carried out, and a vortex will be formed in the middle of the culture tank 1 to discharge the foam in the middle of the water surface. Experiments have verified that the foam formed by aging and dead algal cells and algal vegetation can be discharged after the drain valve 51 is opened for 3-5 minutes.

[0040] The supplemental lighting mechanism 6 includes a supplemental lighting frame 61 and supplemental lights 62. The supplemental lighting frame 61 is installed and fixed on the upper end of the wall of the breeding tank 1. The supplemental lights 62 are fixed on the supplemental lighting frame 61 by a hanging rod 63. Since the breeding tank 1 is circular, the supplemental lights 62 are also designed as rings. Multiple supplemental lights 62 are distributed in concentric circles at intervals. In order to ensure the supplemental lighting effect, the interval between adjacent supplemental lights is 50-60cm. The number of supplemental lights 62 is set according to the diameter of the breeding tank 1, ensuring that a ring of supplemental lights 62 is set every 50-60cm along the diameter of the breeding tank 1.

[0041] The supplemental light 62 includes an acrylic tube and a light strip. The segmented arc-shaped acrylic tube segments are spliced ​​together to form a complete circular tube. The tube contains a light strip, and the LEDs on the light strip can be selected according to the type of algae being cultivated. For example, for green algae such as Chlorella vulgaris and Microchlorophyllariae, red light (630-660nm) and blue light (450-470nm) are used, while for diatoms such as Rhizophora simulans and Phaeodactylum tricornutum, blue light (450-470nm) and white light (full spectrum) are used.

[0042] like Figure 10 As shown, in a specific embodiment, an algae-cleaning component 7 is installed on the supplemental light 62. An algae-cleaning component 7 is set between adjacent hanging rods 63. The algae-cleaning component 7 is used to remove algae cells attached to the supplemental light 62. The algae-cleaning component 7 includes an algae-cleaning block 71 and an algae-cleaning pusher plate 72. The algae-cleaning block 71 is sleeved on the lamp tube of the supplemental light 62, and the algae-cleaning pusher plate 72 is connected to the outside of the algae-cleaning block 71. When the culture water in the culture tank 1 rotates, the water flow acts on the algae-cleaning pusher plate 72, which will push the algae-cleaning component 7 to move on the supplemental light 62 to remove algae cells attached to the supplemental light 62. The algae-cleaning block can be a sponge, silicone, brush, or foamed plastic, etc.

[0043] To enable the algae-cleaning component 7 to reciprocate on the supplemental lighting 62, the culture water in the culture tank 1 needs to rotate clockwise and counterclockwise intermittently, with an interval of 3-5 hours. Therefore, two sets of aeration nozzles 41 are installed at the bottom of the culture tank 1. One set of aeration nozzles 41 drives the culture water to rotate clockwise, and the other set drives it to rotate counterclockwise. The two sets of aeration nozzles 41 are controlled to open or close by electric valves. The counterclockwise rotation of the culture solution drives the algae-cleaning component on the supplemental lighting 62 to slide counterclockwise, and the clockwise rotation drives it to slide counterclockwise. The alternating flow of the culture solution in both directions automatically cleans the supplemental lighting 62.

[0044] like Figure 11 As shown, in a specific embodiment, in order to maintain a suitable temperature of the culture water in the culture tank 1 during winter or in low-temperature environments, and to ensure the normal growth and metabolism of the polysaccharide-containing algae, a heating component can be added to the bottom of the culture tank 1. For example, when the temperature of the culture water is lower than a set threshold (e.g., 5°C), the system can automatically or manually activate the heating function.

[0045] Heating components can be implemented using heating water pipes 8 or electric heating tubes laid at the bottom of the culture tank 1. If heating water pipes are used, they can be arranged in a ring or spiral shape along the bottom of the tank and connected to an external warm water circulation system to achieve indirect and uniform heating through circulating warm fluid. If electric heating tubes are used, they are fixed to the bottom wall of the tank or suspended in the water at the bottom of the tank, and directly heated by electricity to ensure that the temperature of the culture water is stable within the optimal range for algae growth.

[0046] A method for using an automated wastewater discharge polysaccharide-based unicellular algae propagation system. This system can be used individually or in parallel with multiple systems. When multiple systems are used in parallel, one system acts as the mother tank, and the others as daughter tanks. Algae are first propagated in the mother tank. Once the algal solution in the mother tank reaches the required density (e.g., a density of 10⁻⁶),... 6 - 10 7 The algal culture solution is distributed from the mother tank to the daughter tank through the overflow outlet at set intervals. Culture water is added to both the mother and daughter tanks to dilute the algae, and the algae propagation continues. When harvesting algae, algal culture solution is collected from the daughter tank at set intervals, and then collected from the mother tank for further propagation. The set intervals depend on the number of propagation systems used and the algal growth cycle.

[0047] Assuming the algae growth cycle takes 3 days to reach harvest density (e.g., 10), 6 -10 7 (cells / mL), using 4 expansion systems running in parallel, with a set interval of 3 days, and the usage method is as follows:

[0048] Day 1: Inoculate algae into the mother pool (System 1) and begin cultivation.

[0049] Day 4: The algae solution in the mother tank reaches the standard. A portion of the algae solution is diverted to daughter tank 1 (System 2) through the overflow outlet. For example, each time a portion of the algae solution (e.g., 30% by volume) overflows from the mother tank to the daughter tank, fresh culture water and nutrient solution are simultaneously added to the daughter tank to maintain an initial density of approximately 1×10⁻⁶. 5 –5×10 5 cells / mL.

[0050] Day 5: Divert the algal solution from the mother pool to daughter pool 2 (system 3).

[0051] Day 6: Divert the algal solution from the mother pool to daughter pool 3 (system 4).

[0052] Day 7: The algal solution in sub-pond 1 reaches the standard and is harvested; after harvesting, algal solution is added from the mother pond to sub-pond 1 for continued cultivation.

[0053] Day 8: Harvest algae from sub-pond 2 and replenish algae solution.

[0054] Day 9: Harvest algae from sub-pond 3 and replenish algae solution.

[0055] Day 10: Sub-pond 1 completes a new 3-day cultivation cycle, harvests algae again and replenishes the algae solution. Thereafter, harvesting and replenishment are rotated daily in the order of sub-pond 1 → sub-pond 2 → sub-pond 3 to achieve a continuous production rhythm with algae solution production every day.

[0056] Alternatively, when multiple propagation systems have reached a set density of mature algal solution (e.g., 5 × 10⁻⁶), 5 (cells / mL), it can also automatically expand culture and harvest while adding nutrient solution, and be used for feeding shellfish to achieve continuous expansion culture, continuous harvesting and feeding for a long time without cleaning.

[0057] The present invention provides an automated wastewater discharge system and method for cultivating polysaccharide-containing single-celled algae, which has the following advantages:

[0058] It effectively solves the problem of dead water zones. By setting up annularly distributed arc-shaped aeration nozzles at the bottom of the culture tank, the culture medium is driven to form a stable and uniform rotating flow field inside the circular culture tank. This completely eliminates the "dead water zone" caused by uneven flow field in traditional raceway tanks, prevents algal cells from settling and attaching, keeps algal cells in a good suspended state, and improves the uniformity of algal cell suspension.

[0059] This system enables the automatic collection and discharge of aging and dead algal cells. Utilizing the force generated by the rotating water flow, the settled aging and dead algal cells are naturally collected to the central discharge port at the bottom of the tank. Simultaneously, surface foam (such as algal slough) is gathered at the center of the water surface. By activating the discharge pump, the automatic discharge is completed efficiently and quickly (within 3-5 minutes) without manual intervention. The discharged aging algal cells can be directly used as feed for aquatic seedlings, achieving efficient conversion and utilization of biological resources. It can also automatically clean dead algae attached to the supplemental lighting.

[0060] To prevent biofilm formation and water quality deterioration, timely removal of sediments and metabolic waste is crucial to avoid the production of toxic substances such as hydrogen sulfide through anaerobic decomposition, maintain the stability of the culture system's water quality, and ensure a healthy environment for algal cell growth.

[0061] The supplementary lighting adopts a ring-shaped concentric circle spaced distribution design, which can flexibly configure the light source according to the spectral requirements of different algae; the matching algae cleaning component moves back and forth along the lamp tube under the drive of rotating water flow, automatically removing the attached algae film and maintaining light transmittance and light uniformity.

[0062] It supports standalone use and parallel expansion cultivation. Multiple systems can be flexibly combined into a mother-daughter pool parallel mode to achieve step-by-step, continuous, and automated expansion cultivation, greatly improving production efficiency and system stability. It is suitable for industrial microalgae production scenarios.

[0063] However, the above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any substitution of equivalent components or equivalent changes and modifications made in accordance with the scope of protection of the present invention should still fall within the scope of the claims of the present invention.

Claims

1. An automated wastewater discharge system for the propagation of polysaccharide-containing single-celled algae, characterized in that, The system includes a translucent circular culture tank with a central drain outlet at the bottom and an overflow outlet at the top. Multiple aeration nozzles are arranged in a ring inside the tank, connected to an aeration pump via aeration pipes. These nozzles are positioned clockwise or counterclockwise along the tank wall to drive the culture medium within the tank to form a rotating flow field. The expansion system also includes a water injection pipe, a replenishment pipe, a drain pipe, and a ring-shaped supplemental light. The water injection pipe injects culture water, the replenishment pipe injects nutrient solution, and the drain pipe connects to the drain outlet at the bottom of the tank to remove aged or dead algal cells and surface foam. The ring-shaped supplemental light provides sufficient illumination for the expansion system and is equipped with an algae-cleaning component that reciprocates along the lamp tube under the drive of rotating water flow, automatically cleaning the supplemental light.

2. The automatic sewage discharge polysaccharide unicellular algae propagation system according to claim 1, characterized in that, The bottom of the aquaculture tank has a downward-concave curved structure to facilitate the collection of sediment towards the central sewage outlet.

3. The automatic sewage discharge polysaccharide unicellular algae propagation system according to claim 1, characterized in that, The water injection pipe is equipped with a water injection valve or a water injection pump, the liquid replenishment pipe is equipped with a liquid replenishment valve or a liquid replenishment pump, and the sewage discharge pipe is equipped with a sewage discharge valve or a sewage discharge pump.

4. The automatic sewage discharge polysaccharide unicellular algae propagation system according to claim 3, characterized in that, The water injection valve, liquid replenishment valve, and drain valve are either manual or automatic valves.

5. The automatic sewage discharge polysaccharide unicellular algae propagation system according to claim 1, characterized in that, The number of ring-shaped fill lights is multiple, and the multiple ring-shaped fill lights are distributed in concentric circles at intervals.

6. The automatic sewage discharge polysaccharide unicellular algae propagation system according to claim 5, characterized in that, The spacing between adjacent ring lights is 50-60 cm.

7. The automatic sewage discharge polysaccharide unicellular algae propagation system according to claim 1, characterized in that, The bottom of the aquaculture tank is equipped with a heating water pipe or an electric heating pipe.

8. The automatic sewage discharge polysaccharide unicellular algae propagation system according to claim 5, characterized in that, The algae-removing component includes an algae-removing block fitted onto the lamp tube and an algae-removing pusher plate connected to the outside of the algae-removing block. The algae-removing block is one of sponge, silicone, brush, or foamed plastic.

9. A method of using an automatic wastewater discharge polysaccharide unicellular algae propagation system, characterized in that, An automatic sewage discharge polysaccharide unicellular algae propagation system as described in any one of claims 1-8 includes the following steps: multiple propagation systems are connected in parallel, one as a mother tank and the others as daughter tanks; algae are inoculated and cultivated in the mother tank; when the algal solution in the mother tank reaches a set density, a portion of the algal solution is diverted to a daughter tank through an overflow outlet or a pipe with a valve, and cultivation water and nutrient solution are added to the daughter tank; thereafter, algal solution is diverted to other daughter tanks sequentially at set intervals; after the algal solution in the daughter tank reaches a harvesting density, harvesting is carried out sequentially, and after harvesting, algal solution is added from the mother tank to the daughter tank, thereby achieving initial continuous, step-by-step propagation production; or when multiple propagation systems have reached a set density of mature algal solution, automatic propagation and automatic harvesting are achieved while adding nutrient solution, for use in shellfish feeding, realizing continuous propagation and continuous harvesting and feeding without cleaning.

10. The method of using the automatic sewage discharge polysaccharide unicellular algae propagation system according to claim 9, characterized in that, The set interval depends on the number of propagation systems used and the algae growth cycle.

Images