Method for treating eutrophication of large water body and special system thereof

Abstract

The application discloses a large water body eutrophication rapid treatment method and a special system thereof, and comprises a harbor type net enclosure captive breeding salvage unit, a water level self-adaptive cutting pump suction unit, a flume self-flow transportation unit and a solid-liquid separation resource unit. The method absorbs pollutants through net enclosure captive breeding purification organisms, and the whole net is dragged to a shore-based still water harbor by a tugboat during salvage. The organisms enter a cutting bin through a water level self-adaptive gate and the net is recovered synchronously. After the organisms are cut and broken into slurry, the slurry is lifted to an overhead flume by a cutter suction pump, and is self-flowed to a solid-liquid separation bin by gravity. Finally, the slurry is dewatered through filter pipe seepage, anaerobic fermentation and enhanced pressure filtration, so as to realize resource utilization of biogas, organic fertilizer and irrigation water. The application has very strong treatment capacity, is ecological friendly, has very low energy consumption and cost, and can rapidly improve the water quality of a large water body from poor V class to I-II class.

Description

Technical Field

[0001] This invention belongs to the field of water environment management technology, specifically relating to a method and a dedicated system for treating eutrophication in large water bodies using aquatic plants. Background Technology

[0002] Currently, the treatment of eutrophication in large water bodies mainly falls into two technical approaches: chemical methods and ecological purification. Chemical methods are fast-acting but costly, and some recalcitrant pollutants are difficult to remove, potentially leading to secondary pollution risks. The other approach is ecological purification, which involves planting reeds, water celery, and cultivating aquatic plants such as water hyacinth and water peanut, utilizing their strong absorption capacity for pollutants like nitrogen and phosphorus to purify the water.

[0003] However, ecological purification technology faces a core challenge: these plants must be removed from the water promptly and thoroughly before they die; otherwise, the nitrogen and phosphorus they have absorbed will be released again, causing "secondary pollution" and rendering the entire remediation effort futile. Currently, the subsequent treatment of aquatic plants, due to their massive scale, suffers from deficiencies in harvesting, transportation, subsequent dehydration, and resource utilization, resulting in low treatment efficiency and high costs. Specifically, this manifests in the following aspects: 1. Existing salvage equipment is inadequate: Some salvage vessels are equipped with collection boxes to classify and collect salvaged aquatic plants and floating debris. However, these specialized salvage vessels have significant drawbacks: the plants have high water content and are heavy, requiring large vessels with deep drafts, making it difficult to reach some shallow water areas. Furthermore, the vessel must be maneuvered close to the floating debris to salvage it plant by plant, resulting in low efficiency. Other methods involve towing the debris to the shore with purse seine nets and then using transport vehicles for loading, but this method suffers from low transport efficiency and is prone to clogging of the loading inlet.

[0004] 2. Some processing steps are prone to secondary pollution: Some patents involve dehydration and separation directly on board the vessel, with the wastewater discharged directly into the water body to reduce the weight of the salvaged items; others utilize water waves to separate root sediment from the plant body. However, in reality, the sediment attached to plant roots also contains pollutants and is not suitable for direct separation in the water. The dehydrated water from the plants also contains large amounts of pollutants such as nitrogen and phosphorus. Some existing technologies may cause secondary pollution of the water body during the salvage, transportation, and processing stages.

[0005] 3. High energy consumption of pressure filtration and dehydration: Currently, fresh plant materials are generally chopped and then dehydrated by pressure filtration through spiral conveyor or belt roller filtration. Some require multiple pressure filtrations, and the energy consumption of pressure filtration and dehydration is several times that of cutting. Pressure filtration is generally carried out in small batches and cannot complete the centralized pressure filtration of thousands or even tens of thousands of tons at a low energy consumption in one go.

[0006] 4. Difficulty in landfilling during the process of fermentation and harmless resource utilization: Studies have shown that after anaerobic fermentation, the moisture content of plants will be greatly reduced after biogas resource utilization. However, it is extremely difficult to evenly pile the biogas residue in each compartment of the landfill area, and the final cleaning of the biogas residue is difficult. Lack of systematic integration; the entire chain of "salvage-transportation-post-processing" has not been streamlined. Existing patented technologies mostly focus on a single stage such as salvage, collection, cutting, or fermentation, and have not yet formed a systematic integrated solution from efficient absorption of water pollutants to rapid salvage, efficient cutting, long-distance transportation, and post-treatment resource recovery. For example, Chinese patent CN201110078045.7 discloses a technology for segmenting and removing water hyacinth using a net-like tugboat and for shore-based treatment. Its core idea is to use a cutting vessel to cut large areas of water hyacinth into sections, which are then towed to the shore by a tugboat. It also proposes the idea of ​​separating the water hyacinth from other floating debris and transferring it to a dedicated treatment plant or sewage treatment plant. However, this patent only remains at the conceptual framework level. It does not provide a specific operable device for separating water hyacinth from floating debris, nor does it solve the energy consumption and cost problems during long-distance transportation, nor does it provide an engineering-ready implementation plan for subsequent resource recovery. Therefore, this technology is difficult to achieve low-cost, large-scale, and routine operation in practical applications. For example, Chinese patent CN202010666016.1 discloses a method for ecological environment management of rivers and lakes, which uses a stirring unit to clean up aquatic plants. This method only involves the salvage stage and does not extend to subsequent transportation and resource utilization.

[0007] Due to the lack of a systematic integrated solution, many large lakes and reservoirs remain in a state of eutrophication for a long time. These water bodies have extremely high water quality requirements, and currently rely heavily on costly chemical treatment methods to ensure that the effluent meets standards. Ecological purification methods, however, have not yet achieved large-scale, routine engineering application due to technical bottlenecks in aquaculture, harvesting, and post-treatment processes.

[0008] Therefore, there is an urgent need to develop a new system and method for the efficient captive breeding, harvesting, low-energy transportation, and resource-based treatment of aquatic plants under large-scale, continuous operation conditions, so as to bridge the "last mile" of ecological purification technology and enable it to be truly applied to the rapid and low-cost treatment of eutrophication in large sensitive water areas. This is the key problem that this invention aims to solve. Summary of the Invention Purpose of the invention:

[0009] In view of the shortcomings of existing technologies, such as low salvage efficiency, high energy consumption and cost, and easy secondary pollution, this invention provides a high-efficiency, eco-friendly, and resource-utilizable low-cost rapid treatment method for eutrophication of large water bodies and its dedicated system. Technical solution:

[0010] A rapid eutrophication treatment system for large-scale water bodies, characterized in that it comprises: 1. A harbor-type net enclosure and collection unit is used to contain and collect purifying organisms in a water body to rapidly reduce the concentration of eutrophic substances in the water. It includes a column fixed to the bottom of the water, a semi-submersible net detachably connected to the column, and a tugboat or other towing facility for towing the net. The tugboat tows the net together with the purifying organisms gathered inside to a shore-based harbor adjacent to the subsequent cutting area. The harbor is equipped with a wave-dissipating wall to protect the water in the harbor from external wind and waves, providing a calm water operation environment for the smooth docking of the net and the cutting area. 2. Water Level Adaptive Cutting Pump Suction Unit: Connected to the salvage unit, this unit receives the purified organisms and cuts them into a biological slurry for pumping and lifting. It is divided into two compartments: a cutting compartment and a lifting compartment. The cutting compartment is equipped with a movable gate adaptable to changes in the external water level, a level regulation system for adjusting the internal water level, and traction and cutting devices for the purified organisms. The suction pumping compartment pumps and lifts the biological slurry, including a suction pump and a filter screen at the pump inlet. The pump pit is slightly lower than the cutting compartment unit. 3. Aqueduct gravity transport unit: connected to the outlet of the cutter pump, it is an elevated aqueduct with a longitudinal slope, which uses gravity to transport the bio-slurry over long distances. 4. Solid-liquid separation and resource utilization unit: connected to the aqueduct unit, used to receive biological pulp and perform solid-liquid separation and recycling. It is divided into two chambers: a solid-liquid separation chamber and a tailwater chamber. The solid-liquid separation chamber is equipped with a filter tube for dewatering and desiccation and a filter press, while the tailwater chamber is equipped with a drainage pump pipe to facilitate resource utilization.

[0011] A rapid eutrophication treatment method for large-scale water bodies based on the above system, characterized by comprising the following steps: 1. Enclosure process: Purifying organisms are enclosed in the target area of ​​the water body using pillars and netting, allowing the organisms to grow naturally and quickly absorb nitrogen and phosphorus pollutants in the water. 2. Steps for adjusting the height of the inlet gate of the cutting chamber: Adjust the height difference between the inlet gate and the water level outside the chamber so that it is slightly higher than the water level outside the chamber; 3. Towing procedure: When the purification organisms have flowered and grown, disconnect the netting from the posts, and have the netting and the purification organisms gathered inside be towed by a tugboat to the entrance gate of the cutting pretreatment unit with a harbor. 4. Netting Traction and Recycling Steps: Using the traction winch inside the cutting chamber, the purification organisms are pulled into the cutting chamber through the netting while the netting is simultaneously traction and recycled. 5. Liquid level adjustment steps: Start the liquid level adjustment system to adjust the water level in the cutting chamber and control the water content of the bio-slurry after cutting, so as to facilitate pumping and reduce water consumption. 6. Cutting Step: Start the cutting device to break down the purified biological material into biological pulp; 7. Pumping and gravity transport steps: The bio-slurry is lifted to the starting point of the aqueduct by a cutter pump, and then the bio-slurry flows by gravity along the aqueduct with a longitudinal slope to the filter tube dewatering solid-liquid separation resource utilization unit. 8. Solid-liquid separation and resource utilization steps: The bio-slurry is continuously separated into solid and liquid through percolation. After the solid-liquid separation bin is full and biogasification fermentation is completed, the solid residue is subjected to a centralized pressure filtration to reduce its volume, and the remaining water is further drained. The residue is used to make fertilizer or generate electricity, and the liquid is used for ecological irrigation. Beneficial effects

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. Eco-friendly: Through the semi-submersible enclosure design, the enclosure depth is controlled at 0.5-1.5m, without touching the bottom of the water, and the salvage process does not affect fish and other benthic aquatic animals; the entire cutting, pumping and transportation process is carried out in a closed or semi-closed system, with no spillage or leakage, and will not cause secondary pollution to the water body.

[0013] 2. High Efficiency and Energy Saving: First, the shore-based harbor and wave-dissipating wall design effectively reduces external wind and waves, creating a stable operating area. This allows tugboats to tow the entire purse seine net into the cutting chamber, solving the persistent problem of difficult material intake in open water. Second, through the overall purse seine net salvage strategy, utilizing the natural buoyancy of purified organisms, small tugboats can complete harvesting tasks hundreds of times their own load-bearing capacity. The cutting workshop is equipped with a water level adaptive gate system, ensuring a stable drop of 5-10cm between the top of the gate and the outer water body, allowing direct pulling into the cutting chamber without the need for transfer equipment. Long-distance transportation via pumping and lifting followed by gravity flow through aqueducts or pipelines avoids multiple loading and unloading transfers. The solid-liquid separation process uses gravity-fed dehydration through filter tubes, consuming almost no energy. The entire system requires only a small amount of manpower to complete the entire process of "collection—cutting—transportation—resource recovery," reducing overall energy consumption by more than 90% compared to traditional methods.

[0014] 3. Stable operation: By installing a filter screen (3-10mm aperture) at the inlet of the squeegee pump, large particles of plant tissue that have not been fully cut are effectively intercepted, preventing blockage of the pump body and pipelines; it can be used in conjunction with a backwashing device to ensure long-term continuous and stable operation of the system.

[0015] 4. Resource recycling: Through the evenly distributed filter tubes of the solid-liquid separation resource unit, the solid and liquid are automatically separated. The solid part is used for anaerobic fermentation to produce biogas and organic fertilizer, while the liquid part (effluent) is rich in nitrogen and phosphorus nutrients and is transported to the surrounding farmland and pasture through pipelines for ecological irrigation, thus transforming the biological pulp into usable resources and realizing a circular economy.

[0016] 5. Extremely low operating costs: Calculations show that the average power consumption of this system is less than 0.1 kWh per ton of plants processed. Including personnel and equipment maintenance costs, the comprehensive operating cost is approximately 0.2-0.3 yuan / ton. Because water hyacinths have an extremely strong absorption capacity for pollutants such as nitrogen and phosphorus in water, each kilogram of water hyacinth can improve approximately 3 cubic meters of water from Class V surface water to Class I-II water quality standards. Based on this calculation, the comprehensive cost of this system for treating each ton of water is far less than 0.01 yuan, thousands of times lower than traditional chemical methods (breakpoint chlorination, etc.) and more than 90% lower than traditional mechanical dredging and landfill methods, demonstrating significant economic advantages.

[0017] 6. High processing capacity: Small vessels in this system can harvest thousands of tons at a time, continuously cutting, pumping, burying and dehydrating, fermenting and producing biogas. The daily processing capacity can reach tens of thousands of tons. Assuming the solid-liquid separation resource bin is 100m×100m×10m, after the tailwater (rich in nitrogen and phosphorus) from the solid-liquid seepage separation is discharged in time, it can accumulate 1 million tons of aquatic plants for gravity-fed storage. Finally, it undergoes a reinforced centralized pressure filtration to reduce volume, achieving centralized slag discharge in one go. It can meet the massive biological treatment requirements of water purification processes with a capacity of billions of cubic meters.

[0018] 7. Rapid treatment speed: Under appropriate control of the breeding density of water hyacinth, water peanut and other aquatic plants, large water bodies can be upgraded from Class V surface water to Class I-II water quality standards within a few months, rapidly changing the water quality of some eutrophic rivers and lakes in my country.

[0019] 8. High scalability: This system adopts a modular design, which can be flexibly configured according to the water area and treatment scale, including the number of enclosure units and cutting workshops, the number of cutting machines, and the size and number of solid-liquid separation chambers. It is suitable for various water bodies such as rivers, lakes, and reservoirs, and provides an economical and feasible technical path for solving the problem of eutrophication treatment in large and extra-large water sources. Attached image description:

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 This is a plan of a harbor-style net enclosure for aquaculture and salvage.

[0022] Figure 3 This is a cross-sectional view of the water level adaptive cutting pump suction unit.

[0023] Figure 4 This is a plan view of the water level adaptive cutting pump suction unit.

[0024] Figure 5 This is a cross-sectional view of the gravity-flow conveying unit of the aqueduct.

[0025] Figure 6This is a plan view of the solid-liquid separation and resource utilization unit. Explanation of reference numerals in the attached figures:

[0026] 100-Harbor-type enclosure netting for aquaculture and salvage unit; 110-Post; 120-Semi-submersible enclosure net; 121-Float; 130-Tugboat; 140-Detachable connector; 150-Shore-based harbor; 160-Wave wall.

[0027] 200-Water level adaptive cutting pump suction unit: 210-Cutting chamber; 211-Water level adaptive gate system; 2111-Gate; 2112-Water-stop rubber; 2113-Hidden gate housing; 2114-Guide rail; 2115-Pulling jack; 2116-Inlet and return oil circuit; 2117-Oil circuit motor; 212-Guide plate; 220-Liquid level regulation system: 221-Inlet valve; 222-Discharge hole; 223-Liquid level gauge; 230-Cutting device system: 231-Cutting blade assembly; 232-Cutting motor assembly; 240-Traction device; 241-Traction drum; 250-Cutter suction pumping unit system: 251-Cutter suction pump; 252-Filter screen; 253-Maintenance ladder; 300 - Gravity-flowing transport unit for aqueduct; 310 - Aerial aqueduct; 320 - Maintenance access road; 330 - Guardrail; 400 - Post-treatment and resource recovery unit; 410 - Solid-liquid separation chamber; 411 - Vertical drainage pipe; 412 - Drainage hole; 413 - Filter screen; 420 - Wastewater collection chamber; 421 - Irrigation pump pipe. Detailed Implementation

[0028] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. The following examples are used to illustrate the present invention, but are not intended to limit the scope of protection of the present invention.

[0029] Example 1: A rapid treatment method and dedicated system for eutrophication in large water bodies like Figure 1 As shown, this embodiment provides a rapid treatment system for eutrophication in large water bodies, including: a harbor-type net enclosure and dredging unit 100, a water level adaptive cutting pump suction unit 200, an aqueduct gravity flow transport unit 300, and a post-treatment and resource recovery unit 400.

[0030] I. Harbor-type enclosure netting for aquaculture and salvage unit (100 units) The harbor-type net enclosure and harvesting unit 100 is used to contain and collect purified organisms (such as water hyacinth and water peanut) in the water. It includes: several posts 110 fixed to the bottom of the water, a semi-submersible net 120 detachably connected to the posts 110, a tugboat 130 for towing the net 120, a shore-based harbor 150, and a wave-damping wall 160.

[0031] Specifically, the posts 110 are driven into the underwater stratum along the predetermined boundary of the enclosure area, forming a rectangular enclosure. One post is driven into each of the four corners. The depth into the stratum must meet a certain horizontal bearing capacity, preferably 5-10m. The semi-submersible enclosure net 120 has a float 121 at its upper edge and no counterweight at its lower edge, but it is connected to the upper edge with a rope of equal strength, ensuring its natural descent depth is controlled to 0.5-1.5m, preventing it from touching the bottom and ensuring that bottom-dwelling aquatic animals such as fish are not affected during the retrieval process. The enclosure net 120 is connected to the posts 110 via detachable connectors 140 (such as shackles or quick hooks).

[0032] Under normal growth conditions, the enclosure net 120 is fixed to the posts 110 to limit the growth range of the purification organisms. During retrieval, operators disconnect the connector 140, and a tugboat 130 tows the enclosure net 120, along with the purification organisms gathered inside, to the shore-based harbor 150. The shore-based harbor 150 is equipped with a wave-damping wall 160, which can effectively reduce external wind and waves, keeping the water in the harbor essentially still, transforming uncontrollable open water into controllable still water, and providing a stable operating environment for the subsequent purification organisms to smoothly enter the water level adaptive cutting pump suction unit 200.

[0033] II. Water level adaptive cutting pump suction unit 200 The water level adaptive cutting pump unit 200 is installed on the shoreline and is used to receive purified organisms, cut and crush them into biological slurry, and then pump them up. It includes: a water level adaptive cutting chamber 210, a liquid level regulating system 220, a cutting device 230, a net traction and recovery device 240, and a cutter suction pump unit 250.

[0034] (a) Water level adaptive cutting chamber 210 The cutting chamber 210 has a lock-like structure, and its capacity is determined based on the total amount of biological material processed and purified daily. The bottom of the chamber should be slightly lower than the normal water level. The cutting chamber 210 is equipped with a water level adaptive gate system 211, a cutting device 230, a net traction and recovery device 240, and a liquid level regulation system 220.

[0035] (ii) Water level adaptive gate system 211 and guide plate 212 The water level adaptive gate system 211 includes a gate 2111, a water-stop rubber 2112, a gate housing 2113, a guide rail 2114, a top-pull jack 2115, an inlet and outlet oil passage 2116, and an oil passage motor 2117, which together form a gantry lifting mechanism.

[0036] Its working principle is as follows: A water level sensor monitors the water level outside the cutting chamber in real time. The control system drives the hydraulic motor 2117, which in turn drives the jack 2115 via the inlet and outlet hydraulic lines 2116. This causes the gate 2111 to move up and down along the gate housing 2113 and guide rail 2114, automatically adjusting the elevation of the gate 2111 so that the top of the gate is always slightly higher than the water level outside the chamber, with the height difference maintained within 5-10 cm. A water-stop rubber 2112 is installed between the gate 2111, the gate housing 2113, and the guide rail 2114, serving as a seal to prevent water leakage.

[0037] The advantages of this elevation difference are twofold: firstly, the water outside the chamber cannot freely enter the cutting chamber 210 due to the obstruction of the gate 2111, reducing the burden of pumping and treating ineffective water; secondly, under the pulling force of the traction device 240, the purifying organisms can smoothly climb over the top of the gate and enter the cutting chamber 210 with the help of their own buoyancy and the guidance of the guide plate 212. The guide plate 212 is suspended and supported on the gate 2111, with its lower part submerged in the water, which plays an upward guiding role in the retrieval of the purifying organisms and prevents the plant matter from accumulating and blocking the gate.

[0038] The adaptive water level design eliminates the need for additional conveyors or grab buckets, enabling seamless integration of netting retrieval and shoreline cutting.

[0039] (III) Liquid level control system 220 The liquid level regulation system 220 includes an inlet valve 221, a discharge port 222, and a level gauge 223, used to regulate the liquid level in the cutting chamber 210. Based on the consistency of the bio-slurry in the cutting chamber 210 and the real-time detection data of the level gauge 223, the system controls the opening and closing of the inlet valve 221 to regulate the water content of the bio-slurry, facilitating pumping and reducing water consumption.

[0040] (iv) Cutting device 230 The cutting device 230 is disposed within the cutting chamber 210 and includes a cutting blade assembly 231 and a cutting motor assembly 232. The cutting blade assembly 231 can adopt a dual-axis shredding type or a high-speed rotating blade type structure, and the blade gap is adjustable, preferably adjusted so that the plant particle size after cutting is less than 3mm. The purifying organisms are completely crushed within the cutting chamber 210, forming a slurry with a water content of approximately 90%.

[0041] (v) 240 mesh fencing traction and recovery device The netting traction and recovery device 240 is driven by an electric motor to rotate the traction roller 241, thereby traction and recovery of the netting 120. During the recovery process, the netting 120 pulls all the purified organisms inside into the cutting chamber 210, achieving simultaneous unloading and netting recovery. The traction roller 241 can be equipped with a limit guide mechanism to ensure smooth recovery of the netting 120, and the netting can be reused after being cleaned.

[0042] (vi) Screw suction pumping unit 250 The suction pumping unit 250 is connected to the discharge port 222 of the cutting chamber 210 and is used to lift and transport the bio-slurry to the starting point of the aqueduct 300. It includes a suction pump 251, a filter screen 252, and a maintenance ladder 253.

[0043] The filter screen 252 has a pore size of 3-10mm, preferably 3mm×3mm, and is used to intercept large, insufficiently cut plant tissue particles to prevent blockage of the pump body and pipelines. To ensure continuous operation, a backwashing device (not shown in the figure) can also be installed at the filter screen 252. When the filter screen 252 becomes clogged, it is cleaned by reverse water flow. The head of the cutter pump 251 needs to be determined based on the elevation difference between the reservoir area and the cutting point and the pipeline head loss; a wear-resistant slurry pump is preferred. The maintenance ladder 253 is located on the side of the cutter pump 251 for easy daily inspection and maintenance.

[0044] IV. Aqueduct gravity transport unit 300 The aqueduct gravity transport unit 300 is connected to the outlet of the cutter pump 251 and is used to transport biomass slurry over long distances to the post-processing area. It preferably uses an elevated aqueduct 310, which has a longitudinal slope along the transport direction of not less than 1‰ (preferably 2‰). To facilitate the inspection and maintenance of the elevated aqueduct 310, it is equipped with a maintenance access road 320 and guardrails 330 on its sides.

[0045] The aqueduct 300 can be a reinforced concrete structure or a prefabricated U-shaped trough. After being lifted to the starting point of the aqueduct 300 by the cutter pump 251, the biomass flows by gravity along the aqueduct 300 to the post-treatment unit. No other external power is required throughout the process, which greatly reduces transportation energy consumption and efficiency.

[0046] V. Solid-Liquid Separation and Resource Utilization Unit 400 The post-processing and resource recovery unit 400 is located at the end of the aqueduct 310 and is used to receive biomass and perform resource recovery. It consists of two parts: a solid-liquid separation chamber 410 and a tailwater collection chamber 420.

[0047] (a) Solid-liquid separation chamber 410 The solid-liquid separation chamber 410 is equipped with a vertical drainage pipe 411, which is covered with a filter screen. The bottom of the pipe extends to the sand and gravel filter layer below the bottom plate of the chamber. This filter layer is connected to the drainage hole 412 of the tailwater collection chamber 420. The drainage hole 412 connecting the two chambers is equipped with a filter screen 413. The spacing between the pipes can be determined according to the properties of the biological pulp, preferably about 8m, and can be fixed by steel or concrete columns.

[0048] After the bio-slurry enters the solid-liquid separation chamber 410, the water seeps into the tailwater collection chamber 420 through the perforated pipe 411 under gravity, achieving energy-free dewatering. Depending on the amount of bio-slurry and the ambient temperature, the dewatering time is approximately 7-10 days.

[0049] To meet the needs of large-scale continuous operation, the solid-liquid separation chamber 410 is equipped with aqueduct main roads and several branch roads. By opening and closing different branch road systems, the biological pulp can be orderly distributed to different areas in the chamber, realizing overall stacking and gravity pressure filtration, and the water contained in the biological pulp is basically drained and removed.

[0050] After the aforementioned seepage dewatering, the solid residue undergoes simultaneous anaerobic fermentation in the solid-liquid separation chamber 410, producing biogas for power generation or purification. If the moisture content of the biogas residue remains high after fermentation, a pressure plate can be installed above the residue, or road-type compaction equipment (such as a road roller or loader) can be used for overall pressure filtration and volume reduction. By applying external mechanical pressure, residual water in the biogas residue is further discharged and flows into the tailwater collection chamber 420 through the bottom perforated pipe 411, thus achieving enhanced dewatering of the entire chamber in one step. This enhanced dewatering step, performed after fermentation, ensures the smooth progress of the anaerobic fermentation process and further reduces the volume of the biogas slurry; simultaneously, it eliminates the need to remove the biogas residue from the chamber, avoiding secondary transfer and material loss, significantly improving dewatering efficiency and the economics of resource recovery.

[0051] The dewatered biogas residue has a significantly reduced moisture content and can be further processed into organic fertilizer. The solid-liquid separation chamber 410 can be equipped with ramps for vehicles to enter and exit, facilitating the mechanized transportation of organic fertilizer.

[0052] (ii) Tailwater collection chamber 420 The tailwater collection chamber 420 is used to collect the tailwater that seeps out of the solid-liquid separation chamber 410. The tailwater is rich in nutrients such as nitrogen and phosphorus. After being temporarily stored in the tailwater collection chamber 420, it is transported to the surrounding farmland and pasture through the irrigation pipeline 421 and pumps to realize the resource utilization of ecological irrigation.

[0053] VI. System Workflow Based on the above system, this embodiment also provides a rapid treatment method for eutrophication of large water bodies, the workflow of which is as follows: 1. Enclosure process: Purification organisms are enclosed in the target water area using 110 columns and 120 netting, allowing them to grow naturally and quickly absorb nitrogen and phosphorus pollutants from the water.

[0054] 2. Towing Procedure: During salvage, disconnect the connection 140 between the seine net 120 and the post 110, and have the tugboat 130 tow the seine net 120, along with the purification organisms gathered inside, to the shore-based harbor 150. The shore-based harbor 150 is equipped with a wave-damping wall 160, which can effectively reduce external wind and waves, keeping the water in the harbor basically still.

[0055] 3. Gate height adjustment steps: The water level adaptive gate system 211 automatically adjusts the height of the gate 2111 according to the real-time monitoring data of the water level outside the chamber, so that its top surface is 5~10cm higher than the water level outside the chamber, which facilitates the smooth pulling of the purification organisms into the cutting chamber, while preventing the free entry of water from outside the chamber.

[0056] 4. Netting Traction and Recycling Steps: Using the traction rollers 241 inside the cutting chamber 210, all the purified organisms are pulled into the cutting chamber 210 through the netting 120. At the same time, the netting 120 is traction and recycling, so that unloading and netting recycling are completed simultaneously. The netting can be reused after being sorted.

[0057] 5. Liquid level adjustment steps: Start the liquid level adjustment system 220, and control the opening and closing of the water inlet valve 221 according to the consistency of the biological pulp in the cutting chamber 210 and the real-time detection data of the liquid level gauge 223, adjust the water level in the cutting chamber 210, control the water content of the biological pulp after cutting, facilitate subsequent pumping and reduce water consumption.

[0058] 6. Cutting step: Start the cutting device 230, and use the cutting blade group 231 to break the purified biological material into biological pulp with a particle size of less than 10mm (preferably less than 3mm), forming a slurry with a water content of about 90%.

[0059] 7. Pumping and gravity transport steps: The cutter pump 251 lifts the bio-slurry through the discharge hole 222 to the starting point of the aqueduct 310. Under the action of gravity, the bio-slurry flows by gravity along the elevated aqueduct 310 with a longitudinal slope (not less than 1‰, preferably 2‰~5‰) to the post-treatment and resource utilization unit 400. No external power is required throughout the process.

[0060] Solid-liquid separation and resource utilization steps: After the biological pulp enters the solid-liquid separation chamber 410, the water seeps into the tailwater collection chamber 420 through the vertical drainage pipe 411 and the sand and gravel filter layer under the action of gravity, realizing energy-free dewatering, and the dewatering time is about 7-10 days. Solid residues are directly anaerobic fermented in solid-liquid separation chamber 410 to produce biogas for power generation or purification. After fermentation, if the moisture content of the biogas residue is still too high, a pressure plate can be installed on top of the biogas residue or road compaction equipment (such as road rollers, loaders, etc.) can be used to perform overall pressure filtration and volume reduction, forcing the residual water to be further discharged, and achieving enhanced dehydration of the entire bin in one go; The dehydrated biogas residue has a significantly reduced moisture content and can be further processed into organic fertilizer, which is then transported by mechanized means via vehicle ramps. The wastewater collected by the tailwater collection tank 420 is rich in nitrogen and phosphorus nutrients. It is transported to the surrounding farmland and pasture through the irrigation pipeline 421 and pumps to realize the resource utilization of ecological irrigation.

[0061] VII. Application As a preferred embodiment, the length of the enclosure net 120 can be determined based on the area to be harvested in one operation, for example, 1000 meters, enclosing an area of ​​approximately 100 mu (about 6.7 hectares), and yielding approximately 5000 tons of purified biological material. The cutting chamber 210 can be equipped with multi-stage cutting devices 230 (such as two sets of cutting blades 231 connected in series) to achieve finer particle size, ensuring that the cut plant particles meet pumping requirements. The aqueduct 310 can be branched according to terrain conditions to transport the biological slurry to multiple post-processing and resource utilization units 400, achieving zoned processing and resource utilization.

[0062] This system is not only suitable for treating large aquatic plants such as water hyacinth and water peanut, but can also be applied to the harvesting and resource utilization of other aquatic plants with high water content (such as duckweed, water chestnut, and algae). Furthermore, the system can also be used for eutrophication control in various large water bodies (such as lakes, reservoirs, and rivers).

[0063] Example 2 (Variant Scheme) As another implementation, the cutting device 230 can use a hammer mill instead of a twin-shaft shredder, which is suitable for aquatic plants such as duckweed and algae with low fiber content, and can effectively reduce cutting energy consumption and improve crushing efficiency.

[0064] The aqueduct 310 can be replaced by HDPE pipe, steel pipe or buried culvert, which is suitable for scenarios with complex terrain, need to be buried or limited by space, and can also realize gravity flow transportation of biological pulp.

[0065] The solid-liquid separation chamber 410 can also be equipped with a forced ventilation or stirring device to accelerate the anaerobic fermentation process and increase biogas production.

[0066] Furthermore, the driving method of the water level adaptive gate system 211 is not limited to hydraulic drive. It can also adopt alternative solutions such as electric push rods and screw jacks, which can also realize the automatic lifting and lowering of the gate 2111 and the adaptive adjustment of water level.

[0067] All of the above variant solutions fall within the protection scope of this invention.

Claims

1. A rapid eutrophication treatment system for large-scale water bodies, characterized in that, include: A harbor-type net enclosure and collection unit (100) is used to enclose and collect purification organisms in a body of water. It includes a post (110) fixed to the bottom of the water, a semi-submersible net (120) detachably connected to the post (110), and a tugboat (130) for towing the net (120) together with the purification organisms gathered inside it to a shore-based harbor (150). The water level adaptive cutting pump suction unit (200) is connected to the salvage unit (100). The water level adaptive cutting pump suction unit (200) includes a cutting chamber (210) and a water level adaptive gate system (211) installed on the cutting chamber. The water level adaptive gate system can automatically adjust the top elevation of the gate according to the water level outside the cutting chamber, so that it is kept slightly higher than the water level outside. It is used to receive the purified organisms and cut and crush them into biological pulp before pumping and lifting them. The aqueduct gravity transport unit (300), connected to the outlet of the water level adaptive cutting pump suction unit (200), is an elevated aqueduct (310) with a longitudinal slope, which uses gravity to transport the bio-slurry over long distances. The solid-liquid separation and resource utilization unit (400) is connected to the aqueduct gravity transport unit (300) and is used to receive bio-slurry and perform solid-liquid separation and recycling.

2. The rapid eutrophication treatment system for large-scale water bodies according to claim 1, characterized in that, The shore-based harbor (150) is equipped with a wave-dissipating wall (160) to protect the water in the harbor from the influence of external wind and waves, thus creating a calm water operating environment.

3. The rapid eutrophication treatment system for large-scale water bodies according to claim 1, characterized in that, The water level adaptive cutting pump suction unit (200) includes: The cutting chamber (210) is equipped with a water level adaptive gate system (211), a liquid level regulation system (220), a cutting device (230) for cutting and purifying organisms, and a traction device (240) for pulling and recovering the enclosure net (120). The slurry pumping unit (250) is connected to the discharge hole (222) of the cutting chamber (210), and includes a slurry pump (251) and a filter screen (252) disposed at the inlet of the slurry pump (251).

4. The rapid eutrophication treatment system for large-scale water bodies according to claim 3, characterized in that, The water level adaptive gate system (211) includes a gate (2111), a water-stop rubber (2112), a gate housing (2113), a guide rail (2114), and a drive mechanism. The drive mechanism drives the gate (2111) to rise and fall according to the real-time monitoring data of the water level outside the storage area, so that the top surface of the gate is always higher than the water level outside the storage area, and the height difference is maintained within the range of 5~10cm.

5. The rapid eutrophication treatment system for large-scale water bodies according to claim 3, characterized in that, The filter screen (252) has a pore size of 3-10mm and is used to intercept large plant tissue particles that are not fully cut; the suction pumping unit (250) is also equipped with a backwashing device for cleaning the filter screen (252).

6. The rapid eutrophication treatment system for large-scale water bodies according to claim 1, characterized in that, The longitudinal slope of the aqueduct gravity transport unit (300) is not less than 1‰, and the elevated aqueduct (310) is provided with a maintenance access road (320) and a guardrail (330) on the side; or, the aqueduct gravity transport unit (300) is a buried pipeline or culvert.

7. The rapid eutrophication treatment system for large-scale water bodies according to claim 1, characterized in that, The solid-liquid separation resource utilization unit (400) includes a solid-liquid separation chamber (410) and a tailwater collection chamber (420); the solid-liquid separation chamber (410) is equipped with a vertical drainage pipe (411), the bottom of which is connected to the tailwater collection chamber (420); the tailwater collection chamber (420) is equipped with an irrigation pump pipe (421) for transporting nitrogen and phosphorus-rich tailwater to farmland or pasture for irrigation.

8. The rapid eutrophication treatment system for large-scale water bodies according to claim 7, characterized in that, The solid-liquid separation chamber (410) is also equipped with an enhanced pressure filtration device for overall pressure filtration and volume reduction of the separated solid materials. The enhanced pressure filtration device is a hoisting pressure plate or a wheel-type rolling mill.

9. A method for rapid treatment of eutrophication in large-scale water bodies based on the system described in any one of claims 1 to 8, characterized in that, Includes the following steps: (1) Enclosure step: Purification organisms are enclosed in the target area of ​​the water body by means of pillars (110) and netting (120) so that the purification organisms can grow naturally and absorb nitrogen and phosphorus pollutants in the water body; (2) Towing procedure: disconnect the netting (120) from the post (110), and the tugboat (130) tows the netting (120) together with the purification organisms gathered inside it to the shore-based harbor (150); (3) Gate height adjustment steps: Based on the real-time monitoring data of the water level outside the tank, automatically adjust the height of the gate (2111) so that its top surface is 5~10cm higher than the water level outside the tank; (4) Net traction and recovery steps: Using the traction device (240) in the cutting chamber (210), the net (120) is used to pull all the purified organisms into the cutting chamber (210) at the same time, and the net (120) is pulled and recovered synchronously. (5) Cutting step: Start the cutting device (230) to break the purified biological material into biological pulp; (6) Pumping and gravity transport steps: The bio-slurry is lifted to the starting point of the aqueduct (310) by a cutter pump (251), and then the bio-slurry flows by gravity along the aqueduct (310) with a longitudinal slope to the solid-liquid separation resource utilization unit (400). (7) Solid-liquid separation and resource utilization process: solid-liquid separation is carried out on the biological pulp. The solid part is anaerobic fermented and then subjected to overall pressure filtration to reduce volume, and then used to make fertilizer or generate electricity. The liquid part is used for ecological irrigation.

10. The rapid treatment method for eutrophication of large water bodies according to claim 9, characterized in that, In the cutting step, the purified biomass is crushed to a particle size of less than 10 mm to form a pumpable bioslurry.

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