Composite bio-based suspension purification system based on near-natural water ecology concept

Abstract

The invention discloses a composite bio-based suspension purification system based on a near-natural water ecology concept, and belongs to the technical field of water ecology diversity restoration. The system is composed of an emergent aquatic plant ecological design module, a bio-based suspension core, a microorganism cultivation bed, an intelligent underwater oxygenation and aeration module, an artificial ecological fish reef and a submerged plant planting module. Wherein the bio-based suspension core is of a four-layer gradient composite structure and comprises a polyester fiber filler layer, an active carbon fiber sponge layer and a palm fiber bio-base layer, and synergistic purification of physical adsorption, chemical degradation and biological metabolism is achieved. The intelligent aeration module dynamically regulates and controls the aeration intensity through multi-parameter sensor linkage and a fuzzy PID algorithm, and the oxygen transfer efficiency is larger than or equal to 35%. According to the invention, through coupling design of aperture gradient distribution (80-92% porosity) of the four-layer gradient bio-based suspension core and a dynamic response threshold value of a fuzzy PID algorithm, collaborative optimization of carrier structure parameters and control system parameters is realized for the first time. The innovative technology not only improves the stability and diversity of an ecological system, but also strengthens the natural purification capacity of a water body, and provides a new thought for water environment protection.

Description

Technical Field

[0001] The present invention relates to the technical field of water ecological restoration, and specifically relates to a composite bio-based suspended purification system based on the concept of near-natural water ecology. Background Art

[0002] With the acceleration of the global urbanization process, ecological degradation caused by water pollution has become a severe environmental challenge. According to statistics, more than 60% of lakes and rivers in China have eutrophication problems (China Environmental Status Bulletin 2023), triggering a series of reactions such as algal blooms and a sharp decline in biodiversity. Although traditional chemical / physical remediation methods can improve water quality in the short term, they cannot reconstruct the self-purification ability of water bodies and ecological balance. Therefore, developing ecological restoration technologies based on nature-based solutions (NbS) to achieve coordinated governance of "water quality purification - habitat reconstruction - food chain restoration" has become the core direction in the international water environment field.

[0003] Current ecological water treatment technologies are mainly divided into three categories: physical, chemical, and biological. Physical methods mainly include mechanical filtration, adsorption, aeration and reoxygenation, and sedimentation / flotation technologies. They can quickly remove suspended solids (SS removal rate > 90%) without chemical residues. However, they are basically ineffective for dissolved pollutants, and have significant defects such as high operating costs (e.g., the cost of replacing activated carbon reaches 500 - 800 yuan / m³ / year), frequent maintenance (requiring backwashing 1 - 2 times a week), and easy fouling of equipment (resulting in a 30% decrease in efficiency). These limitations seriously restrict the individual application effect of physical methods in the in-depth treatment of water bodies and urgently need to be combined with biological or chemical technologies to improve the comprehensive treatment efficiency.

[0004] Chemical methods mainly include chemical precipitation (such as phosphorus removal by aluminum salts / iron salts), oxidation-reduction (ozone, persulfate), and electrochemical treatment technologies. Although they can efficiently remove specific pollutants (TP removal rate > 95%, COD removal rate 50% - 70%), they generally have inherent defects such as a large amount of chemical sludge generation (increasing the treatment cost by 30%), possible destruction of the ecological balance by chemical residues (such as the ozone half-life < 15 minutes), and significant influence of the treatment effect by pH value (the efficiency decreases by 40% when outside the range of 6 - 8). These secondary pollution risks and sensitivity to operating conditions make it difficult for chemical methods to independently meet the requirements of sustainable water ecological restoration, and usually need to be combined with physical or biological technologies to achieve a safer and more economical comprehensive treatment effect.

[0005] Biological methods mainly include the activated sludge process, biofilm methods (such as MBR, MBBR), and ecological engineering technologies (constructed wetlands, ecological floating islands). These technologies utilize microbial metabolism and plant absorption to achieve pollutant removal (the denitrification efficiency of the activated sludge process is 60 - 80%). They have advantages such as low operating costs and environmental friendliness. However, they still face key bottlenecks such as poor stability of the microbial flora (the activity at low temperatures decreases by 70%), significant seasonal influence on treatment efficiency (the efficiency of constructed wetlands decreases by 50% in winter), and single function of traditional ecological floating islands (the TN removal rate < 60%). There is an urgent need to improve treatment efficiency and system stability through technological breakthroughs such as microbial-plant synergistic enhancement and intelligent regulation.

[0006] In recent years, although some studies have attempted to improve the water purification effect by optimizing the structure of biological carriers, enhancing aeration efficiency, or improving plant configuration, the existing technologies generally have prominent problems such as a single regulation method, excessive energy consumption, and poor synergy with the ecosystem. Traditional aeration equipment mostly operates in a fixed-time or fixed-intensity mode and cannot respond dynamically to water quality changes, resulting in a serious mismatch between the supply of dissolved oxygen and the actual demand. This not only causes energy waste (energy consumption accounts for more than 60% of the total operating cost) but also makes it difficult to maintain the optimal activity state of microorganisms. Some studies have attempted to introduce simple sensor control, but due to the lack of multi-parameter collaborative analysis and intelligent algorithm support, the improvement of aeration efficiency is limited (the oxygen transfer efficiency is generally lower than 25%).

[0007] The intelligent underwater aeration module proposed in this invention has achieved a technological leap through three major innovative breakthroughs: First, a micro water quality sensor array (DO, NH3-N, ORP, pH, turbidity) is used to monitor the water quality in the core purification area in real time. Combined with the fuzzy PID algorithm carried by the edge computing controller, it realizes the precise matching of dissolved oxygen supply and microbial metabolic demand (response time < 10 seconds). Second, the innovatively designed gradient pore size nano aeration disk (bubble diameter 50 - 80μm) is combined with a variable frequency air pump (power 50 - 300W stepless adjustment), enabling the oxygen transfer efficiency to break through 35% and being 2.1 times higher than that of traditional equipment. More importantly, this module uses an AI prediction model (LSTM neural network) to predict the water quality change trend in the next 6 - 12 hours, adjusts the aeration strategy in advance, reduces the ineffective aeration time by 20% - 40%, and further reduces energy consumption in cooperation with the solar power supply system (conversion efficiency ≥ 22%). Practical engineering verification shows that while ensuring an NH3-N removal rate > 95%, the unit treatment energy consumption of this intelligent module is reduced to 0.3 kWh / m³, saving more than 40% energy compared with traditional aeration technologies, truly achieving the synergistic optimization of "precision oxygen supply - efficient conversion - low-carbon operation". Summary of the Invention

[0008] In view of the deficiencies of the prior art, the present invention breaks through the above technical bottlenecks through the coupled design of a four-layer gradient bio-based suspended core and an intelligent dynamic aeration system, and for the first time realizes: Carrier-control collaborative optimization: precisely matching the pore gradient (80%-92%) of the bio-based suspended core with the dynamic response thresholds of the fuzzy PID algorithm (DO 3mg / L, NH3-N 0.5mg / L), the denitrification efficiency is increased to 89% (vs 62% of the traditional method); Microbubble-large pore mass transfer enhancement: through the 6-10:1 ratio design of the nano-aeration disk (bubble diameter 50-80μm) and the pore diameter of the palm fiber layer (0.5-5mm), the oxygen transfer efficiency reaches 35% (the industry average is 18%); Ecological chain self-organization construction: emergent plants (C3 / C4 mixed planting) - submerged plants (Vallisneria natans) - microbial film (EPS secretion +67%) - fish reef (3D printed honeycomb structure) form a four-level ecological niche, and the biodiversity is increased by 2.5 times.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A composite bio-based suspended purification system based on the concept of near-natural water ecology, characterized by comprising the following core modules: Emergent plant ecological design module: Configure the ratio of C4 plants (Thalia dealbata, Cyperus alternifolius) to C3 plants (Phragmites australis) as 3:1. The fibrous roots of Cyperus alternifolius (specific surface area 320m² / g) and the taproots of Phragmites australis (depth 1.5m) form a three-dimensional absorption network, and the TP adsorption capacity reaches 45mg / m² / d, which is used to optimize the photosynthesis efficiency and the nitrogen and phosphorus absorption capacity.

[0010] Bio-based suspended core: a four-layer gradient structure (polyester fiber layer + activated carbon fiber sponge layer + palm fiber layer), which is used to intercept suspended solids, adsorb heavy metals, and cultivate into a biofilm.

[0011] Microbial cultivation bed: Bacterial community configuration: Nitrifying bacteria (Nitrosomonas 30% + Nitrobacter 25%) + Denitrifying bacteria (Pseudomonas 20%) + Polyphosphate-accumulating bacteria (Accumulibacter 15%) Cultivation conditions: DO gradient control (0.5-4mg / L), pH self-adaptive adjustment (6.5-8.5) Metabolic efficiency: Nitrification rate 3.8mg / (L·h) (at 20°C), and the denitrifying carbon source utilization rate is increased by 40% (C / N ratio optimized to 5:1). Intelligent underwater aeration module: including a micro water quality sensor unit, an aeration unit, an intelligent algorithm unit, and an energy storage unit: Micro water quality sensor unit, a six-parameter micro probe (DO ±0.1mg / L, NH3-N ±0.05mg / L, ORP ±5mV) is used to monitor multiple data indicators in the water body in real time and transmit the data to the intelligent algorithm unit.

[0012] Intelligent algorithm unit: used to receive sampled data, analyze and process the data, predict and regulate, dynamically generate the optimal aeration plan, and output PWM speed control signals.

[0013] Aeration unit: used to execute responses.

[0014] Energy storage unit: used for power management and distribution of the system.

[0015] Artificial ecological fish reef: 3D printed PHA material to promote biological attachment; Submerged plant module: mixed planting of Vallisneria natans + Myriophyllum spicatum; purification efficiency: root oxygen secretion amount 2.4gO2 / (m²·d) (promote sediment mineralization), allelochemicals (phenolic acids) inhibit algal growth (Chl-a reduction rate 83%).

[0016] Fixed ecological hemp rope: polypropylene matrix + hydrophobic nano-coating (contact angle ≥150°), tensile strength ≥150MPa, UV aging resistance life >8 years Preferably, the bio-based suspension core adopts a gradient composite structure, including: the 1st and 4th layers are polyester fiber filler layers, with a tensile strength ≥120MPa, porosity 83%-87%, having the functions of microbial carriers and anti-aging characteristics; the 2nd layer is an activated carbon fiber sponge layer, with a specific surface area of 1280m² / g, porosity 92%-95%, and phosphorus element adsorption capacity of 45.2mg / g; the 3rd layer is a palm fiber bio-based mesh layer, with a porosity of 76% to 78% and a pore diameter of 0.5mm - 5mm. There is a transition layer between the activated carbon fiber sponge layer and the palm fiber bio-based layer, and this transition layer is composed of nano-hydroxyapatite modified biochar (particle size 50nm - 200nm) and polylactic acid fibers intertwined.

[0017] Preferably, for the preparation of the activated carbon fiber sponge layer, the preparation method includes: carbonizing viscose-based fibers in a nitrogen atmosphere at 600°C for 2h, activating with KOH (impregnation ratio 1:3) at 850°C for 1.5h, and detecting by XPS that the proportion of surface oxygen-containing functional groups reaches 12.6%. Preferably, for the modification of the nano-hydroxyapatite, the preparation method includes: loading hydroxyapatite on biochar by the co-precipitation method / observing by TEM shows that the average particle size of the nanoparticles is 85±12nm / XRD analysis shows that the crystallinity index (CI) reaches 0.92.

[0018] Preferably, for the biochar composite process, the preparation method includes: using the electrostatic self-assembly method: alternately depositing positively charged chitosan (1 wt%) and negatively charged hydroxyapatite (Zeta potential -35 mV) 3 layers / the specific surface area of the composite material reaches 812 m² / g (measured by N2 adsorption-desorption isotherm) Preferably, the micro water quality sensor unit is fixed below the bio-based suspension core, and one set of six-parameter sensors is configured per 5 square meters. An anti-biofouling probe (with an automatic brushing function) is used and connected to the edge computing controller through a waterproof cable for: multi-parameter synchronous acquisition (DO, NH3-N, ORP, turbidity, temperature); data preprocessing (temperature compensation, outlier rejection); data transmission (upload to the computing unit).

[0019] Preferably, the regulation strategy of the intelligent algorithm unit is as follows: (1) When the dissolved oxygen (DO) concentration is detected to be in the range of 3-5 mg / L, the basic aeration control strategy is adopted: Current aeration volume = basic volume × [1 + 0.2 × (5 - current DO value)] For every 1 mg / L decrease in DO, the aeration volume increases by 20% to achieve oxygen deficit compensation (2) When DO is lower than 3 mg / L, enhanced control is triggered: judge the range of gas volume increase according to the NH3-N concentration. If DO is not improved, start the standby air pump and trigger an audible and visual alarm at the same time.

[0020] (3) Predictive response: Input historical data for the past 4 hours, calculate through a three-layer neural network, output the DO change curve for the next 6 hours, the early warning response threshold, and automatically adjust the oxygen addition to adjust the carbon-oxygen ratio.

[0021] (4) Collaborative response: According to the ORP characteristics, select three aeration strategies: intermittent aeration, maintaining the basic gas volume, and pulsed aeration.

[0022] Preferably, the aeration device in the intelligent aeration module consists of a nano-micro pore aeration disk and a variable frequency air pump; the nano-micro pore aeration disks are evenly distributed below the microbial cultivation bed, 10 cm - 20 cm away from the bottom of the bed body, connected through UPVC official websites, and arranged in a grid pattern; the variable frequency air pump is installed in the onshore equipment box and connected to the underwater aeration official website through a pressure-resistant hose.

[0023] Preferably, the aeration device has three modes: basic aeration: 30% power, enhanced aeration: 70% power, emergency aeration: 100% + standby air pump start.

[0024] Preferably, the intelligent computing controller in the intelligent aeration module is fixed in the onshore control box and supports remote transmission.

[0025] Preferably, a solar panel is installed on a support frame in the emergent plant ecological module of the ecosystem.

[0026] Compared with the prior art, the present invention provides a composite bio-based suspended purification system based on the concept of near-natural water ecology, having the following beneficial effects: The present invention has the following remarkable beneficial effects: 1. High-efficiency synergistic purification: Through a four-layer gradient bio-based suspension core, triple synergistic effects of physical adsorption, chemical degradation and biological metabolism are achieved. The denitrification efficiency > 90%, the phosphorus removal efficiency > 92%, and the COD degradation efficiency reaches 30 g / (m²·d). The golden ratio of the bubble diameter (D) to the filler pore diameter (d) is established as d / D = 1.2 - 1.8 (Claims 5, 7), increasing the gas-liquid contact area by 2.3 times, and the peak denitrification efficiency reaches 89%. The combination of the nano-hydroxyapatite modified biochar transition layer (Claim 3) and the carboxyl / amino double modified polyester fiber (Claim 4) reduces the biofilm shedding rate from the industry average of 35% to < 10%.

[0027] 2. Intelligent and precise control: The intelligent aeration module uses multi-parameter sensors for real-time monitoring and combines the fuzzy PID algorithm to achieve dynamic adjustment of the aeration intensity. The oxygen transfer efficiency ≥ 35%, which is 2.1 times higher than that of traditional equipment, and the energy consumption is reduced by more than 40%.

[0028] 3. Enhancement of ecological diversity: A complete food chain of "plants - microorganisms - fish" is constructed, and the biodiversity is increased by 2.5 times, attracting more than 15 types of wild animals to inhabit.

[0029] 4. Energy-saving and environmental protection characteristics: Solar power supply (conversion efficiency ≥ 22%) and bio-based materials (accounting for 78%) are used. The unit treatment energy consumption ≤ 0.3 kWh / m³, and the service life is 8 - 10 years.

[0030] 5. Wide applicability: It is applicable to the ecological restoration of various water bodies such as lakes, rivers, and industrial wastewater. The installation and maintenance are simple, and the operation is stable and reliable. This technology breaks through the limitation of the single function of traditional ecological floating islands and integrates elements such as intelligent aeration control, multi-stage biofilm cultivation, and biological chain reconstruction for the first time to form a near-natural water ecological restoration system with self-regulating ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the overall structure of the composite bio-based suspended purification system of the present invention Figure 2 It is a schematic diagram of the composition of the bio-based suspension core in the composite bio-based suspended purification system of the present invention Figure 3 It is a working flow chart of the intelligent underwater aeration module of the present invention Figure 4 Schematic diagram of the underwater design module of the present invention Specific embodiments

[0032] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments in the following description are only examples, and other obvious variations can be conceived by those skilled in the art.

[0033] Example Comparative Example 1: Optimization comparison of the bio-based suspended core structure Control group: Traditional single-layer biological filler (polypropylene fiber, porosity 85%) Experimental group: Four-layer gradient bio-based suspended core of the present invention (structure of claim 2) Test conditions: The same water quality (TN = 5mg / L, TP = 0.8mg / L, COD = 60mg / L), consistent aeration volume Results: Conclusion: The pore size gradient design of the activated carbon fiber layer (adsorbing heavy metals) and the palm fiber layer (microbial habitat) enables the step-by-step degradation of pollutants, and at the same time, the transition layer of nano-hydroxyapatite and the root exudates of Vallisneria natans synergistically improve the TP adsorption.

[0034] Example Comparative Example 2: Comparison of the efficiency of intelligent aeration algorithms Control group: Timed aeration (fixed power 200W, on / off time 1:1) Experimental group: Fuzzy PID dynamic aeration (strategy of claim 8) Test conditions: 24-hour simulated water quality fluctuations (DO 2 - 6mg / L, NH3-N 0.3 - 1.2mg / L) Results: Conclusion: The multi-parameter sensor and the fuzzy PID algorithm (claim 6) dynamically match the aeration intensity, combined with the bubble diameter of the nano-aeration disk (50 - 80μm) and the packing porosity ratio (1.2 - 1.8, claim 7), to achieve the optimization of gas-liquid mass transfer.

[0035] Example Comparative Example 3: Verification of the combined effect of ecological modules Control group: Only emergent plant module (Phragmites australis + Cyperus alternifolius) Experimental group: Full-system combination (emergent plants + submerged plants + fish reef + suspended core) Test conditions: Eutrophic lake (initial Chl-a = 50μg / L) Results: Conclusion: Submerged plants (Vallisneria natans) secrete allelochemicals to inhibit algae, and artificial fish reefs (claim 1) provide a biological habitat space, forming a complete food chain with the biofilm of the suspended core.

[0036] Example Comparative Example 4: Verification of the coupling of materials - control parameters Control group: Conventional aeration (bubble diameter 120 μm) + ordinary packing Experimental group: Nano-aeration (bubble diameter 60 μm) + gradient suspension core (d / D = 1.5) Test conditions: High ammonia nitrogen wastewater (NH3-N = 15 mg / L) Results: Conclusion: The ratio of pore diameter to bubble diameter (1.2 - 1.8) enables the bubbles to be fully broken in the packing, increasing the gas-liquid contact area.

[0037] Example Comparative Example 5: Verification of low-temperature environment adaptability Control group: Traditional biofilm packing (polyethylene) + fixed aeration Experimental group: The system of the present invention (carboxyl / amino modified polyester fiber layer + intelligent aeration) Test conditions: Winter water temperature 5 - 8 °C, influent COD = 80 mg / L, NH3-N = 8 mg / L Results: Conclusion: The carboxyl / amino modified fiber layer (enhances the attachment of low-temperature microorganisms, biofilm shedding rate < 10% (vs 35% in the control group); the intelligent aeration module automatically increases the aeration volume by 30% at low temperature according to the ORP compensation strategy to maintain the activity of nitrifying bacteria Example Comparative Example 6: Comparison of shock load resistance Control group: Ordinary ecological floating island (without intelligent regulation) Experimental group: The whole system of the present invention (including LSTM prediction model) Test conditions: Simulating rainstorm runoff impact (instantaneous COD increases from 50 mg / L to 200 mg / L) Results: Conclusion: The LSTM model predicts the load impact 6 hours in advance and triggers the emergency aeration mode; the activated carbon fiber layer (specific surface area 1280 m² / g) quickly adsorbs sudden pollutants, buying buffer time for microbial degradation.

[0038] Example 7: Simulated test of rainstorm impact Comparison of control strategies: Traditional PID control: The aeration volume is fixed and increased by 50%; The predictive control of the present invention: The emergency mode is started 30 minutes in advance Summary table of key process parameters The above supplementary content presents the core technical details of the present invention through specific process parameters, mathematical models, experimental data and comparative tests, which not only meets the full disclosure principle required by the patent law but also retains the confidentiality space of the key processes. All data are from actual test verification and can support the broad protection scope of the claims.

[0039] The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited by the above embodiments, and what is described in the above embodiments and the specification is only the principle of the present invention. Without departing from the spirit and scope of the present invention, various changes and improvements will occur to the present invention, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection required by the present invention is defined by the appended claims and their equivalents.

Claims

1. A composite bio-based suspension purification system based on the concept of near-natural water ecology, characterized by: include: The emergent plant ecological design module (1) is equipped with hydrangea, reed and Cyperus rotundus; the bio-based suspension core (2) is composed of PET polymer material, high-density 3D soft material and plant fiber; the microbial cultivation bed (3) is used to cultivate nitrification and denitrification microorganisms; the intelligent underwater oxygenation aeration module (4) includes a micro water quality sensor and an intelligent computing unit, an aeration unit and an energy storage unit; the artificial ecological fish reef (5) adopts a 3D printed honeycomb structure; the submerged plant planting module (6) is planted with Vallisneria and Myriophyllum; the fixed ecological hemp rope (7) is used to fix the system.

2. The composite bio-based suspension purification system according to claim 1, characterized in that: The bio-based suspension core (2) is divided into four layers from top to bottom: the first and fourth layers are polyester fiber fillers with a porosity of 85%±2%; the second layer is an activated carbon fiber sponge layer with a specific surface area of ​​≥1280m² / g, which can quickly capture suspended particles, colloidal substances and organic pollutants in water through physical adsorption, and fix heavy metals (such as Pb) through chemical adsorption. 2+ 、Cd 2+ The third layer is the palm fiber biological base layer, which is used to meet the needs of microbial film formation and provide a three-dimensional space for plant root development and animal habitat.

3. The composite bio-based suspension purification system according to claim 2 is characterized in that: A transition layer is provided between the activated carbon fiber sponge layer of the bio-based suspension core (2) and the palm fiber bio-based layer. The transition layer is composed of nano-hydroxyapatite modified biochar (hydroxyapatite loading 10-30wt%, particle size 50-200nm) interwoven with polylactic acid fibers. When the ratio of the pore diameter of the activated carbon fiber sponge layer to the diameter of the aeration bubbles is controlled at 1.2-1.8, the system denitrification efficiency reaches a peak value (>89%).

4. The composite bio-based suspension purification system according to claim 1, characterized in that: The surface of the fourth layer of polyester fiber filler of the bio-based suspension core (2) is grafted with carboxyl and amino functional groups, and the adhesion strength of the microbial film is enhanced through electrostatic action, and the biofilm shedding rate is less than 10%.

5. The composite bio-based suspension purification system according to claim 1, characterized in that: The pore size of the third layer of palm fiber bio-based layer of the bio-based suspension core (2) is 0.5-5 mm, and the ratio of the diameter of the bubbles of the nano-aeration disk of the intelligent underwater oxygenation aeration module (4) of 50-80 μm is 6-10:1, thereby forming a micro-bubble-macropore coupled mass transfer channel. When the ratio of the pore diameter of the activated carbon fiber sponge layer to the diameter of the aeration bubbles is controlled at 1.2-1.8, the system denitrification efficiency reaches a peak value (>89%).

6. The composite bio-based suspension purification system according to claim 1, characterized in that: The intelligent underwater oxygenation aeration module (4) comprises: a micro water quality sensor array for detecting dissolved oxygen, ammonia nitrogen, redox potential and pH value; a nano aeration disk with a bubble diameter of 50-80 μm; a variable frequency air pump with an adjustable power range of 50-300 W; and an edge computing control unit for realizing dynamic adjustment based on a fuzzy PID algorithm.

7. The composite bio-based suspension purification system according to claim 4, characterized in that: The pore size distribution of the activated carbon fiber sponge layer satisfies: when the intelligent aeration module outputs a bubble diameter of 50-80 μm, the ratio of the pore diameter d of the filler layer to the bubble diameter D is d / D=1.2-1.8, so that the bubble crushing rate in the filler is ≥70%, and the gas-liquid contact area is increased by 2.3 times compared with conventional fillers.

8. The composite bio-based suspension purification system according to claim 1, characterized in that: The control algorithm of the intelligent underwater oxygenation aeration module (4) adopts a multi-parameter coupling feedback mechanism, specifically including: dissolved oxygen (DO) priority regulation: when DO<3mg / L, aeration is started, and the air pump power is adjusted according to the DO recovery rate; ammonia nitrogen (NH3-N) coordinated control: when NH3-N>0.5mg / L, the aeration intensity is increased by 15%-20% to promote nitrification reaction; oxidation-reduction potential (ORP) compensation: when ORP<-100mV (anaerobic conditions), the aeration volume is increased by 30% to inhibit anaerobic bacteria from producing methane and hydrogen sulfide; pH adaptive regulation: when pH<6.5 or>8.5, the aeration strategy is adjusted to avoid a decrease in microbial activity.

9. The composite bio-based suspension purification system according to claim 4, characterized in that: The system in the intelligent underwater oxygenation aeration module (4) further comprises a solar power supply module connected to the intelligent underwater oxygenation aeration module (4), wherein the solar panel conversion efficiency is ≥22% and the energy storage battery capacity is ≥200Wh, for achieving energy self-sufficiency.

10. The composite bio-based suspension purification system according to claim 1, characterized in that: The root secretions of Vallisneria planted in the submerged plant module (6) increase the secretion of extracellular polymers (EPS) of the biofilm by 67%, and synergize with the nano-hydroxyapatite in the transition layer to increase the TP removal rate by 14%.

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