Marine organism comprehensive culture method using biogas liquid to culture plant biological bait

Abstract

This invention relates to a method for integrated marine aquaculture using biogas slurry to cultivate plant-based feed, belonging to the field of mariculture. The outlet of the biogas slurry storage area is connected to the plant feed cultivation area via a main biogas slurry outlet pipe. The plant feed cultivation area is connected to the plant feed inlet pipe via a filter pump. The sludge outlet of the biogas slurry storage area is connected to the bottom sludge treatment area via a main sludge discharge pipe. An aeration stone is installed at the bottom of the bottom sludge treatment area, connected to an aeration pipe. The biogas slurry storage area is higher than both the bottom sludge treatment area and the plant feed cultivation area. The sludge outlet of the bottom sludge treatment area is connected to the integrated aquaculture area via a bottom sludge feeding pipe. The bottom sludge treatment area and the plant feed cultivation area are higher than the integrated aquaculture area. The plant feed cultivation area is connected to the integrated aquaculture area via a main algae feeding pipe. The integrated aquaculture area is equipped with an intertidal water exchange gate, enabling continuous use of biogas slurry. Spatial isolation of different feeding animals achieves biodiversity and effectively avoids food competition, ensuring the stability of the entire aquaculture system.

Description

Technical Field

[0001] This invention relates to the field of marine aquaculture, specifically a method for integrated marine aquaculture that utilizes biogas slurry to cultivate plant-based feed. Background Technology

[0002] As is well known, biogas slurry is a high-concentration organic wastewater produced by the anaerobic fermentation of livestock and poultry manure and other organic matter. It not only contains abundant nutrients such as nitrogen, phosphorus, and potassium, but also humic acid, amino acids, vitamins, and other active substances that promote crop growth, making it an excellent liquid fertilizer for fields. The resource utilization of biogas slurry can save irrigation water and reduce the amount of chemical fertilizer used, thus having great potential for widespread application. Land absorption is the main method of biogas slurry treatment in my country. However, different crop-soil systems have different absorption capacities for biogas slurry. Over-application of biogas slurry on-site can cause problems such as seedling burn, soil compaction, and groundwater pollution. Therefore, the widespread and rational utilization of biogas digester residue is a comprehensive issue, which is not only beneficial to agricultural production but also has a significant positive impact on improving the ecological environment.

[0003] In current mariculture, farmed animals are typically fed artificially formulated feed. However, poor palatability of the feed and the impact of uneaten feed on the aquatic environment lead to low stocking densities and stagnant production efficiency. Single-celled algae, macroalgae, bacteria, and fungi are high-quality biological feeds and probiotic communities for many mariculture species (oysters, abalone, and other shellfish, as well as filter-feeding fish). These feeds are highly palatable, and uneaten feed, especially plant-based feed, is environmentally friendly, not only purifying the aquatic environment but also providing oxygen. Processed and properly concentrated biogas slurry serves as an excellent culture medium for these plant-based biological feeds and probiotic communities. The small organic particles in the biogas slurry are also a good food source for benthic organisms such as sea cucumbers. Therefore, utilizing biogas slurry to cultivate plant-based biological feeds and probiotics for scientific, multi-species integrated aquaculture can not only improve production efficiency but also provide a continuous supply of high-quality mariculture protein. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides a method for integrated marine aquaculture using biogas slurry to cultivate plant-based feed, which enables continuous use of biogas slurry and ensures the stability of the entire aquaculture system.

[0005] The technical solution adopted by this invention to solve its technical problem is: a marine biological integrated aquaculture device that uses biogas slurry to cultivate plant biological feed, characterized by a biogas slurry storage area, wherein the outlet of the biogas slurry storage area is connected to the plant feed cultivation area via a main biogas slurry outlet pipe, the plant feed cultivation area is connected to the plant feed inlet pipe via a filter pump, the slag outlet of the biogas slurry storage area is connected to the bottom slag treatment area via a main slag discharge pipe, the bottom of the bottom slag treatment area is equipped with an air stone, the air stone is connected to an air inlet pipe, the biogas slurry storage area is higher than the bottom slag treatment area and the plant feed cultivation area, the slag outlet of the bottom slag treatment area is connected to the integrated aquaculture area via a bottom slag feeding pipe, the bottom slag treatment area and the plant feed cultivation area are higher than the integrated aquaculture area, the plant feed cultivation area is connected to the integrated aquaculture area via a main algae feeding pipe, and the integrated aquaculture area is equipped with an intertidal water exchange gate.

[0006] This invention can also be achieved through the following measures: The biogas slurry storage area includes three biogas slurry storage tanks. Each biogas slurry storage tank is equipped with a first metering valve, a second metering valve, a third metering valve, and a fourth metering valve from top to bottom. The first metering valve, the second metering valve, the third metering valve, and the fourth metering valve are connected to the main biogas slurry outlet pipe, which is equipped with a main biogas slurry outlet valve.

[0007] The biogas slurry storage tank has a gently sloping bottom with a slag discharge pipe at its lowest point. The slag discharge pipe has a valve and converges into the main slag discharge pipe.

[0008] The bottom slag treatment area is equipped with a bottom slag treatment pool, and the main slag discharge pipe is connected to the bottom slag treatment pool. The bottom of the bottom slag treatment pool is equipped with an air-filled stone, which is connected to an air-filling pipe.

[0009] The bottom of the bottom slag treatment tank is designed with a gentle slope, and there is an opening at the lowest point to connect to the bottom slag feeding pipe. The bottom slag feeding pipe is equipped with a bottom slag control valve.

[0010] The plant feed cultivation area includes five plant feed cultivation tanks. Each plant feed cultivation tank has an air stone at the bottom, which is connected to an air inlet pipe. The bottom of the plant feed cultivation tank is equipped with a waterproof LED light source. A biogas slurry main outlet pipe is provided above each plant feed cultivation tank, and each biogas slurry spray pipe has a biogas slurry control valve.

[0011] The plant feed culture tank has a gently sloping bottom with an opening at its lowest point connecting to an algae liquid outlet pipe. The algae liquid outlet pipe is equipped with an algae liquid control valve, and the algae liquid outlet pipe of the plant feed culture tank is connected to the main algae liquid feeding pipe.

[0012] The integrated aquaculture area includes an integrated aquaculture pond, which is an intertidal aquaculture pond. The bottom sludge feeding pipe enters along the bottom of the integrated aquaculture pond and branches out into multiple parallel branch pipes. Spray holes are distributed on the branch pipes, which are distributed throughout the bottom of the integrated aquaculture pond. The aquaculture cages and aquaculture boxes are distributed in the upper part of the integrated aquaculture pond and fixed on the floating pipes.

[0013] The beneficial effects of this invention are that it enables the continuous use of biogas slurry, completely solves the problem of biogas slurry resource utilization, and achieves biodiversity by spatially isolating animals with different diets and effectively avoids food competition, thus ensuring the stability of the entire aquaculture system. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0015] Figure 1 A schematic diagram of the structure of the present invention.

[0016] Figure 2 This is a schematic diagram of the biogas slurry storage area.

[0017] Figure 3 This is a schematic diagram of the bottom slag treatment tank.

[0018] Figure 4 This is a schematic diagram of the structure of the plant feed cultivation area.

[0019] Figure 5 This is a schematic diagram of the integrated aquaculture pond.

[0020] In the picture biogas slurry storage area Plant feed cultivation area Bottom slag treatment area, Integrated aquaculture area, 1. Main biogas slurry outlet pipe, 2. Main sludge discharge pipe, 3. Main algae feeding pipe, 4. Bottom sludge feeding pipe, 5. Biogas slurry storage tank, 6. Biogas slurry outlet, 7. First metering valve, 8. Second metering valve, 9. Third metering valve, 10. Fourth metering valve, 11. Main biogas slurry outlet valve, 12. Sludge discharge pipe, 13. Valve, 14. Bottom sludge treatment tank, 15. Air stone, 16. Bottom sludge control valve, 17. Plant feed cultivation tank, 18. Air stone, 19. Waterproof LED light source, 20. Biogas slurry spray pipe, 21. Biogas slurry control valve, 22. Algae slurry outlet pipe, 23. Algae slurry control valve, 24. Integrated aquaculture tank, 25. Branch pipe, 26. Aquaculture cage, 27. Aquaculture box, 28. Intertidal water exchange gate, 29. Filter pump, 30. Floating pipe. Detailed Implementation

[0021] Figure 1 Zhongzuo slurry storage area The slurry outlet connects to the plant feed cultivation area via the main slurry outlet pipe 1. Connected plant feed cultivation area After passing through filter pump 29 and the plant feed inlet pipe, the biogas slurry storage area... The slag outlet is connected to the bottom slag treatment area via the slag discharge main pipe 2. Connected to the biogas slurry storage area Higher than the bottom ash treatment area and plant feed cultivation area Bottom ash treatment area The slag outlet is connected to the integrated aquaculture area via bottom slag feeding pipe 4. Connected to the bottom ash treatment area and plant feed cultivation area Higher than the integrated aquaculture area Plant feed cultivation area Through the total algae feeding tube 3 and the integrated aquaculture area Connected, integrated aquaculture area It is equipped with an intertidal zone water exchange gate 28.

[0022] Figure 2 biogas slurry storage area The facility includes three biogas slurry storage tanks 5. The bottom of each tank 5 is 1.2m above ground level, with an internal height of 2.0m, a length of 4m, and a width of 2m. Each tank 5 has four biogas slurry outlets 6 distributed from top to bottom. The heights of the four outlets 6 from the bottom of the tank are 150cm, 105cm, 60cm, and 8cm, respectively. These outlets are connected via biogas slurry outlet pipes to a first metering valve 7, a second metering valve 8, a third metering valve 9, and a fourth metering valve 10. The outlets of these valves converge into a main biogas slurry outlet pipe 1, which has a main outlet valve 11. The bottom of each tank 5 has a gentle slope, with a slag discharge pipe 12 at the lowest point. A valve 13 is mounted on the slag discharge pipe 12. The slag discharge pipes 12 from the three tanks converge into the main slag discharge pipe 2.

[0023] Figure 3 Bottom ash treatment area A bottom slag treatment tank 14 is provided, which is 0.8m above the ground. The main slag discharge pipe 2 is connected to the bottom slag treatment tank 14. The bottom of the bottom slag treatment tank 14 is equipped with aerated stones 15, with a distribution density of 1 stone / m². 2 The bottom of the slag treatment tank 14 is designed with a gentle slope, and there is an opening at the lowest point to connect to the bottom slag feeding pipe 4. The bottom slag feeding pipe 4 is equipped with a bottom slag control valve 16.

[0024] Figure 4 Plant feed cultivation area Five plant food cultivation tanks 17 are provided. Each plant food cultivation tank 17 is 1m high, 15m long, and 10m wide. Each plant food cultivation tank 17 has air stones 18 at the bottom, with a distribution density of 0.2 air stones / m³. 2 The bottom of the plant feed cultivation pond 17 is equipped with a waterproof LED light source 19. The main biogas slurry outlet pipe 1 is equipped with a biogas slurry spray pipe 20 above each plant feed cultivation pond 17. Each biogas slurry spray pipe 20 has a biogas slurry control valve 21 and biogas slurry spray holes. The bottom of the plant feed cultivation pond 17 is designed with a gentle slope, and the lowest point has an opening to connect to the algae slurry outlet pipe 22. Each algae slurry outlet pipe 22 is equipped with an algae slurry control valve 23. The algae slurry outlet pipes 22 of the five plant feed cultivation ponds 17 are connected to the main algae slurry feeding pipe 3.

[0025] Figure 5 Integrated aquaculture area The integrated aquaculture pond 24 is 3.5m deep, 300m long and 200m wide. The integrated aquaculture pond 24 is an intertidal aquaculture pond. The bottom sludge feeding pipe 4 enters along the bottom of the integrated aquaculture pond 24 and branches out into multiple parallel branch pipes 25. Spray holes are distributed on the branch pipes 25. The branch pipes 25 are distributed throughout the bottom of the integrated aquaculture pond 24 and are spaced 3 meters apart. The filter feeder cages 26 and scraper feeder boxes 27 are distributed in the upper part of the integrated aquaculture pond 24 and are fixed on the floating pipes.

[0026] In this invention, the biogas slurry is first introduced into three biogas slurry storage tanks 5 for sedimentation 24 hours in advance. Then, on the first day, filtered seawater is injected into the first plant feed cultivation tank 17 via filter pump 29, and air stones 18 are used for aeration. The first metering valve 7 and the total biogas slurry outlet valve 11 of the highest biogas slurry outlet 6 of the first biogas slurry storage tank 5 are opened, allowing the biogas slurry to pass through the biogas slurry control valve 21 to the biogas slurry spray pipe 20, which sprays the biogas slurry into the first plant feed cultivation tank 17 for cultivation. The biogas slurry addition volume is 2.4 m³. 3 Once the nitrogen concentration reaches 30 ppm, close the first metering valve 7 and add a high concentration of Chlorella seed to the first plant feed culture tank 17 for cultivation, so that the initial seed density is 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source 19 at the bottom of the pool, and continuously aerate through the air stone 18; the next day, filtered seawater is injected into the second plant feed cultivation pool 17 via the filter pump 29, the air stone 18 is aerated, and the first metering valve 7 and the total biogas slurry outlet 6 of the first biogas slurry storage pool 5 are opened. The biogas slurry is sprayed into the second plant feed cultivation pool 17 through the biogas slurry control valve 21 and the biogas slurry spray pipe 20. When there is no biogas slurry flowing out of the first metering valve 7, the second metering valve 8 is opened. When the biogas slurry addition reaches 2.4m 3Once the nitrogen concentration reaches 30 ppm, close the second metering valve 8 and the total effluent valve 11. Add a high concentration of Chlorella seed to the second plant feed culture tank 17 to achieve an initial seed density of 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source 19 at the bottom of the pool, and continuously aerate the air stones 18; on the third day, filtered seawater is injected into the third plant feed cultivation pool 17 via the filter pump 29, the air stones 18 are aerated, and the second metering valve 8 and the total biogas slurry outlet valve 11 of the first biogas slurry storage pool 5 are opened. The biogas slurry is sprayed into the third plant feed cultivation pool 17 through the biogas slurry control valve 21 and the biogas slurry spray pipe 20. When the biogas slurry addition reaches 2.4m³, 3 Once the nitrogen concentration reaches 30 ppm, close the second metering valve 8 and the total biogas slurry outlet valve 11, and add a high concentration of Chlorella seed to the third plant feed culture tank 17 to achieve an initial seed density of 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source 19 at the bottom of the pool, and continuously aerate the air stones 18; on the fourth day, filtered seawater is injected into the fourth plant feed cultivation pool 17 via the filter pump 29, the air stones 18 are aerated, and the second metering valve 8 and the main outlet valve 11 of the biogas slurry outlet 6 of the first biogas slurry storage pool 5 are opened. The biogas slurry is sprayed into the fourth plant feed cultivation pool 17 through the biogas slurry control valve 21 and the biogas slurry spray pipe 20. When no biogas slurry flows out of the second metering valve 8, the third metering valve 9 is opened. When the biogas slurry addition reaches 2.4m³, 3 Once the nitrogen concentration reaches 30 ppm, close the third metering valve 9 and the total outlet valve 11, and add a high concentration of Chlorella seed to the fourth plant feed culture tank 17 to achieve an initial seed density of 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source 19 at the bottom of the pool, and continuously aerate the air stones 18; on the fifth day, filtered seawater is injected into the fifth plant food cultivation pool 17 via the filter pump 29, the air stones 18 are aerated, and the third metering valve 9 and the total biogas slurry outlet valve 11 of the first biogas slurry storage pool 5 are opened. The biogas slurry is then directed through the biogas slurry control valve 21 to the biogas slurry spray pipe 20, and sprayed into the fifth plant food cultivation pool 17. When the biogas slurry addition reaches 2.4m³, 3 Once the nitrogen concentration reaches 30 ppm, close the third metering valve 9 and the total effluent valve 11. Add a high concentration of Chlorella seed to the fifth plant feed culture tank 17 to achieve an initial seed density of 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source 19 at the bottom of the pool, and continuously aerate the air stones 18; after 5 days of cultivation in the first plant feed culture pool 17 to reach the feeding density, open the algae control valve 23 on the algae liquid outlet pipe 22 at the bottom of the first plant feed culture pool 17 to allow the unicellular algae to flow into the integrated aquaculture pool 24 through the total algae feeding pipe 3. On the sixth day, filtered seawater is injected into the middle pool of the first plant feed culture pool 17 via the filter pump 29, the air stones 18 are aerated, and the third metering valve 9 and the total biogas liquid outlet valve 11 of the biogas liquid storage pool 5 are opened. The biogas liquid is sprayed into the first plant feed culture pool 17 through the biogas liquid control valve 21 to the biogas liquid spray pipe 20. When there is no biogas liquid flowing out of the third metering valve 9, open the fourth metering valve 10, and the biogas liquid addition volume is 2.4m³. 3 Once the nitrogen concentration reaches 30 ppm, close the fourth metering valve 10 and the total effluent valve 11. Add a high concentration of Chlorella seed to the first plant feed culture tank 17. The initial seed density is 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source 19 at the bottom of the pool, and continuously inflate the air stone 18; after 5 days of cultivation in the second plant feed cultivation pool to reach the feeding density, open the algae control valve 23 on the algae liquid outlet pipe 22 at the bottom of the second plant feed cultivation pool 17 to allow the unicellular algae to flow into the integrated aquaculture pool 24. On the seventh day, filtered seawater is injected into the second plant feed cultivation tank 17 via filter pump 29. Air stones 18 are used for aeration. The fourth metering valve 10 and the main biogas slurry outlet valve 11 of the first biogas slurry storage tank 5 are opened. The biogas slurry is sprayed into the second plant feed cultivation tank 17 through the biogas slurry control valve 21 and the biogas slurry spray pipe 20. When no biogas slurry flows out of the fourth metering valve 10, it is closed. The first metering valve 7 at the highest position of the second biogas slurry storage tank 5 is opened, and simultaneously, the valve 13 on the sludge discharge pipe 12 of the biogas slurry storage tank 5 is opened, allowing the bottom sludge to flow into the bottom sludge treatment tank 14. Probiotics are added to the bottom sludge treatment tank 14, and after 24 hours of aeration by air stones 15, the bottom sludge control valve 16 of the bottom sludge feeding pipe 4 is opened, allowing the bottom sludge to flow into the bottom of the integrated aquaculture tank 24. The sludge is then dispersed to the licking animal breeding area through the branch pipe 25 with spray holes. This process is repeated, and the biogas slurry in the second and third biogas slurry storage tanks 5 is used for integrated aquaculture.

[0027] On spring tides, the integrated aquaculture pond 24 received water through the intertidal water exchange gate 28, and 1132 kg of large sea cucumber seedlings were scattered into the bottom. Filter-feeding oysters were cultured in cages 26 within the pond. These cages were hooked onto tubular floats (4 meters long), with six cages 26 attached to each float. Four tubular floats were connected in series, totaling 300 strings. Each cage 26 contained 1.0 kg of large oyster seedlings, for a total of 7200 kg of large oyster seedlings. The water temperature was 20-30℃, salinity 29-32, and pH 7.8-8.1. The water was changed every two weeks on spring tides. After 30 days of culture, a total of 2523 kg of sea cucumbers and an average of 9.3 kg of oysters per cage were harvested, for a total yield of approximately 66960 kg.

[0028] This system can also be used for integrated farming of scrapers and lickers. After seawater is added to the plant feed cultivation tank 17, air stones are used for aeration. The metering valves of the first biogas slurry storage tank 5 are opened sequentially to inject an appropriate amount of biogas slurry. When no biogas slurry flows out of the fourth metering valve 10, it is closed. The first metering valve 7 at the highest position of the second biogas slurry storage tank 5 is opened, and simultaneously the valve 13 on the sludge discharge pipe 12 of that biogas slurry storage tank 5 is opened, allowing the bottom sludge to flow into the bottom sludge treatment tank 14. When the nitrogen concentration in the plant feed cultivation tank 17 reaches 20 ppm, large algae are added, and the waterproof LED light source 19 at the bottom of the tank is turned on. Probiotics are added to the bottom sludge treatment tank 14, and aeration is achieved through the air stones 15. After 24 hours of treatment, the bottom sludge control valve 16 of the bottom sludge feeding pipe 4 is opened to allow the bottom sludge to flow into the bottom of the integrated aquaculture pond 24. The large algae in the plant feed culture pond 17 are cultured for 3-5 days, and then a portion is selected and harvested to feed the scraping animals raised in the culture box 27 in the integrated aquaculture pond 24. At the same time, the algae liquid control valve 23 on the algae liquid outlet pipe 22 at the bottom of the plant feed culture pond 17 is opened to allow the seawater used to cultivate the large algae to flow into the integrated aquaculture pond 24. Then, the filter pump 29 is turned on to inject filtered seawater into the plant feed culture pond 17 and add biogas slurry to continue cultivating the remaining large algae. This method cultivates sea urchins and sea cucumbers in the integrated aquaculture of Ulva lactuca for 60 days, with sea urchins and sea cucumbers gaining weight by 32% and 21%, respectively.

[0029] This invention utilizes concentrated biogas slurry as fertilizer, avoiding pollution caused by biogas slurry discharge, achieving resource recycling, and possessing high ecological value. The differentiated design of each functional area is energy-efficient, highly effective, and easy to operate and manage. The biogas slurry undergoes pre-sedimentation in a storage tank, and flows out gradually from top to bottom, preventing strong water flow from suspending biogas residue and carrying it into the plant feed cultivation tank. Two or more biogas slurry storage tanks ensure a continuous supply for storage and recycling. The biogas residue, after aeration, becomes probiotic flocs, serving as nutrient particles for benthic lickers, avoiding waste and environmental pollution. Artificial light sources are designed at the bottom of the plant feed cultivation tank, overcoming the disadvantages of cloudy days, darkness, and shading from upper plants that hinder plant growth, greatly improving the growth efficiency of plant feed and the conversion efficiency of various nutrients in the biogas slurry, effectively resolving the supply-demand contradiction between plant feed and animal feeding. The plant feed cultivation pond is suitable for cultivating both unicellular algae and macroalgae. Different types of plant feed can be cultivated according to the season, environmental conditions, and the needs of farmed animals to ensure the continuity of biogas slurry treatment and a continuous supply of plant feed. The integrated aquaculture pond achieves biodiversity and effectively avoids food competition by spatially isolating animals with different feeding habits, thus ensuring the stability of the entire aquaculture system. The integrated aquaculture pond is an intertidal pond, and water can be changed during spring tides according to the ebb and flow of the tides. The filter-feeding animal aquaculture cages are connected in series with tubular floats for easy harvesting. The scraper-feeding animal aquaculture cages use two tubular floats connected in parallel to facilitate the feeding of macroalgae feed.

Claims

1. A method for integrated marine aquaculture using biogas slurry to cultivate plant-based feed, wherein the integrated marine aquaculture device includes a biogas slurry storage area; the outlet of the biogas slurry storage area is connected to a plant-based feed cultivation area via a main biogas slurry outlet pipe; the plant-based feed cultivation area is connected to a plant-based feed inlet pipe via a filter pump; the sludge outlet of the biogas slurry storage area is connected to a bottom sludge treatment area via a sludge discharge main pipe; the bottom of the bottom sludge treatment area has an aeration stone connected to an aeration pipe; the biogas slurry storage area is higher than both the bottom sludge treatment area and the plant-based feed cultivation area; the sludge outlet of the bottom sludge treatment area is connected to the integrated aquaculture area via a bottom sludge feeding pipe. The bottom sludge treatment area and the plant feed cultivation area are connected, with the latter being higher than the integrated aquaculture area. The plant feed cultivation area is connected to the integrated aquaculture area via a main algae feeding pipe. The integrated aquaculture area is equipped with an intertidal water exchange gate. The biogas slurry storage area includes three biogas slurry storage tanks. The plant feed cultivation area includes five plant feed cultivation tanks. Each plant feed cultivation tank has an air stone at the bottom, which is connected to an air inflator. The bottom of the plant feed cultivation tank is equipped with a waterproof LED light source. The main biogas slurry outlet pipe is equipped with a biogas slurry spray pipe above each plant feed cultivation tank, and each biogas slurry spray pipe has a biogas slurry control valve. Its features are, First, input the biogas slurry into three biogas slurry storage tanks for sedimentation 24 hours in advance, and then perform the following steps: Step 1: On the first day, filtered seawater is injected into the first plant-based food cultivation tank via a filter pump. Air stones are used for aeration. The first metering valve at the highest biogas slurry outlet of the first biogas slurry storage tank and the main biogas slurry outlet valve are opened, allowing the biogas slurry to be sprayed into the first plant-based food cultivation tank. Chlorella seed is then added to the first plant-based food cultivation tank, with the initial seed density set at 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source at the bottom of the pool, and continuously inflate the pool with air stones; Step 2: On the second day, after filtration: Filtered seawater is injected into the second plant feed cultivation tank, air stones are used for aeration, and the first metering valve at the highest biogas slurry outlet of the first biogas slurry storage tank and the total biogas slurry outlet valve are opened, allowing the biogas slurry to be sprayed into the second plant feed cultivation tank. When no biogas slurry flows out of the first metering valve, the second metering valve is opened. When the biogas slurry addition reaches 2.4m³... 3 Once the nitrogen concentration reaches 30 ppm, close the second metering valve and the total effluent valve for the biogas slurry, and add the Chlorella seed to the second plant feed culture tank to achieve an initial seed density of 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source at the bottom of the pool, and the bubble stones continue to inflate; Step 3: On the third day, filtered seawater is injected into the third plant-based food cultivation tank via a filter pump. Air stones are used for aeration. The biogas slurry outlet of the first biogas slurry storage tank and the main biogas slurry outlet valve are opened, allowing the biogas slurry to be sprayed into the third plant-based food cultivation tank. When the biogas slurry addition reaches 2.4 m³... 3 Once the nitrogen concentration reached 30 ppm, the Chlorella seed was added to the third plant-based food culture tank, resulting in an initial seed density of 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source at the bottom of the pool, and the bubble stones continue to inflate; Step 4: On the fourth day, filtered seawater is injected into the fourth plant feed cultivation tank via a filter pump. Air stones are used for aeration. The second metering valve and the main outlet valve of the first biogas slurry storage tank are opened, allowing the biogas slurry to be sprayed into the fourth plant feed cultivation tank. When no biogas slurry flows out of the second metering valve, the third metering valve is opened. When the biogas slurry addition reaches 2.4 m³... 3 Once the nitrogen concentration reaches 30 ppm, close the valve and add the Chlorella seed to the fourth plant feed culture tank, making the initial seed density 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source at the bottom of the pool, and the bubble stones continue to inflate; Step 5: On the fifth day, filtered seawater is injected into the fifth plant feed cultivation tank via a filter pump. Air stones are used for aeration. The third metering valve at the biogas slurry outlet of the first biogas slurry storage tank and the main biogas slurry outlet valve are opened, allowing the biogas slurry to be sprayed into the fifth plant feed cultivation tank. When the biogas slurry addition reaches 2.4m³... 3 Once the nitrogen concentration reaches 30 ppm, close the valve and add the Chlorella seed to the fifth plant feed culture tank, making the initial seed density 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source at the bottom of the pool, and the bubble stones continue to inflate; Step 6: After culturing the first plant-based food culture tank for 5 days to reach the feeding density, open the algae control valve on the algae outlet pipe at the bottom of the first plant-based food culture tank, allowing the unicellular algae to flow into the integrated aquaculture tank through the main algae feeding pipe. On the sixth day, inject filtered seawater into the middle tank of the first plant-based food culture tank via a filter pump, aerate with air stones, and open the third metering valve and the main biogas outlet valve of the first biogas slurry storage tank. The biogas slurry flows through the biogas slurry control valve to the biogas slurry spray pipe, spraying the biogas slurry into the first plant-based food culture tank. When no biogas slurry flows out of the third metering valve, open the fourth metering valve, adding 2.4 m³ of biogas slurry. 3 Once the nitrogen concentration reaches 30 ppm, close the fourth metering valve and the total effluent valve for biogas slurry, and add the Chlorella seed to the first plant feed culture tank. The initial seed density is 50 × 10⁻⁶. 5 / ml, turn on the waterproof LED light source at the bottom of the pool, and the bubble stones continue to inflate; Step 7: After 5 days of cultivation in the second plant feed cultivation pond to reach the feeding density, open the algae control valve on the algae outlet pipe at the bottom of the second plant feed cultivation pond to allow the unicellular algae to flow into the integrated aquaculture pond. On the seventh day, inject filtered seawater into the middle pond of the second plant feed cultivation pond through a filter pump, aerate with air stones, open the fourth metering valve and the total biogas slurry outlet valve of the first biogas slurry storage pond to spray biogas slurry into the second plant feed cultivation pond. When there is no biogas slurry flowing out of the fourth metering valve, close the fourth metering valve, open the first metering valve at the highest position of the second biogas slurry storage pond, and at the same time open the valve on the sludge discharge pipe of the biogas slurry storage pond to allow the bottom sludge to flow into the bottom sludge treatment pond. Add probiotics to the bottom sludge treatment pond, and after 24 hours of aeration with air stones, open the bottom sludge control valve on the bottom sludge feeding pipe to allow the bottom sludge to flow into the bottom of the integrated aquaculture pond and be dispersed to the licking animal breeding area through the branch pipe with spray holes. Step 8: Continue in this manner and cycle through the process, using the biogas slurry from the second and third biogas slurry storage tanks for integrated aquaculture.

2. The method for integrated marine aquaculture using biogas slurry to cultivate plant-based feed according to claim 1, characterized in that, The lowest point of the plant feed culture tank has an opening that connects to the algae liquid outlet pipe. The algae liquid outlet pipe is equipped with an algae liquid control valve. The algae liquid outlet pipe of the plant feed culture tank is connected to the main algae liquid feeding pipe.

3. The integrated marine aquaculture method for cultivating plant-based feed using biogas slurry according to claim 1, characterized in that, The biogas slurry storage area includes three biogas slurry storage tanks. Each biogas slurry storage tank is equipped with a first metering valve, a second metering valve, a third metering valve, and a fourth metering valve from top to bottom. The first metering valve, the second metering valve, the third metering valve, and the fourth metering valve converge into the main biogas slurry outlet pipe, which is equipped with a main biogas slurry outlet valve.

4. The method for integrated marine aquaculture using biogas slurry to cultivate plant-based feed according to claim 1, characterized in that, The biogas slurry storage tank has a gently sloping bottom design, and there is a slag discharge pipe at the lowest point of the biogas slurry storage tank. The slag discharge pipe has a valve and converges into the main slag discharge pipe.

5. The method for integrated marine aquaculture using biogas slurry to cultivate plant-based feed according to claim 1, characterized in that, The bottom slag treatment area is equipped with a bottom slag treatment pool, and the main slag discharge pipe is connected to the bottom slag treatment pool. The bottom of the bottom slag treatment pool is equipped with an air-filled stone, which is connected to an air-filling pipe.

6. The integrated marine aquaculture method for cultivating plant-based feed using biogas slurry according to claim 1, characterized in that, The bottom of the slag treatment tank is designed with a gentle slope, and there is an opening at the lowest point to connect to the slag feeding pipe. A slag control valve is installed on the slag feeding pipe.

7. The integrated marine aquaculture method for cultivating plant-based feed using biogas slurry according to claim 1, characterized in that, The plant feed cultivation tank has a gently sloping bottom design.

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