Constructed wetland systems and methods for enhancing ammonia oxidation and phosphorus adsorption with manganese-rich particulate matrix

Abstract

This invention provides an artificial wetland system and method for enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich granular matrix. Utilizing manganese oxides attached to the manganese-rich particles, it achieves deep adsorption of phosphorus-containing pollutants, realizing a coupled manganese-ammonia oxidation artificial wetland system. This achieves deep denitrification and phosphorus removal from nitrogen- and phosphorus-containing wastewater, with effluent meeting the Class V water quality requirements of the Chinese Surface Water Environmental Standard. The system includes: a main wetland system comprising a support zone and a reaction zone arranged above the support zone; an inlet is located at the bottom of the support zone, and an outlet is located on the top side wall of the reaction zone. The reaction zone is filled with manganese-rich granular filler, and wetland plants are planted at the top opening of the reaction zone; the manganese-rich granular filler is a composite of quartz sand and manganese oxides, prepared by coating manganese oxides onto quartz sand; the inlet is connected to an inlet tank via a peristaltic pump, and the outlet is connected to an outlet tank.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to an artificial wetland system for enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich granular matrix. Background Technology

[0002] Nitrogen (N) and phosphorus (P) are essential nutrients for life in nature. However, when nitrogen and phosphorus-containing wastewater from human activities (such as industrial production, agricultural planting, and urban life) is discharged directly into water bodies (rivers, lakes, oceans, etc.) without effective treatment, the concentration of nutrients in the water body will far exceed the natural carrying capacity, leading to eutrophication. This is the fundamental driving force behind the development of nitrogen and phosphorus removal technologies. Therefore, minimizing the nitrogen and phosphorus pollutant load discharged into natural water bodies has become the core approach to controlling eutrophication and ensuring water safety and ecosystem stability.

[0003] In hypoxic environments, the key limiting factor for ammonia nitrogen removal is the lack of electron acceptors. Recent studies have proposed a novel hypoxic ammonia oxidation process that uses mineral oxides (such as iron oxide and manganese oxide) as electron acceptors. Summary of the Invention

[0004] This invention provides an constructed wetland system and method that enhances ammonia oxidation and phosphorus adsorption with a manganese-rich particle matrix. The system is constructed by creating a vertical subsurface flow constructed wetland system, in which manganese-rich particles are added to the reaction zone, which contains NH4. + -N provides electron acceptors, enhancing ammonia oxidation; at the same time, manganese oxides attached to manganese-rich particles are used to achieve deep adsorption of phosphorus-containing pollutants, realizing a manganese-ammonia oxidation artificial wetland coupling system, achieving the purpose of deep nitrogen and phosphorus removal from nitrogen- and phosphorus-containing wastewater, and the effluent can meet the Class V water quality requirements of China's surface water environmental standards.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This application provides an constructed wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particulate matrix, the system comprising:

[0007] A vertical subsurface flow type wetland system body, the wetland system body includes a support area and a reaction area arranged above the support area;

[0008] The bottom of the support area is provided with a water inlet, the top side wall of the reaction area is provided with a water outlet, and the reaction area is filled with manganese-rich granular filler. Wetland plants are planted at the top opening of the reaction area.

[0009] The manganese-rich particle filler is a composite of quartz sand layer and manganese oxide, which is prepared by coating manganese oxide onto quartz sand.

[0010] The inlet is connected to the inlet tank via a peristaltic pump, and the outlet is connected to the outlet tank.

[0011] Preferably, the quartz sand in the manganese-rich particle filler is filled in layers, from bottom to top as follows:

[0012] Coarse quartz sand layers with a height between 0 and 15 cm and a particle size between 4 and 8 mm.

[0013] Medium-sized quartz sand layers with a height between 15 and 35 cm and a particle size between 2 and 4 mm.

[0014] A layer of fine quartz sand with a height between 35 and 55 cm and a particle size between 1 and 2 mm.

[0015] Preferably, the manganese oxide is at least one of manganese dioxide, manganese trioxide, or manganese tetroxide, and its powder particle size is 0.45 μm.

[0016] Preferably, the sidewall of the reaction zone is uniformly provided with multiple matrix sampling ports and multiple water sampling ports from bottom to top.

[0017] Preferably, the roots of the wetland plants are located at the height of the water outlet.

[0018] Preferably, an in-situ detection column is provided in the center of the reaction zone, and the top of the in-situ detection column is higher than the top opening of the reaction zone;

[0019] The in-situ detection column has multiple through holes on its side wall that connect its inner and outer walls.

[0020] The in-situ detection column is equipped with a pH monitoring probe, an oxidation-reduction potential and dissolved oxygen monitoring probe.

[0021] This application also provides a method for wastewater treatment using an constructed wetland system that enhances ammonia oxidation and phosphorus adsorption with the aforementioned manganese-rich granular matrix, comprising the following steps:

[0022] The inlet pipe connects the inlet tank, peristaltic pump, and inlet at the bottom of the wetland system to the inlet in sequence; the outlet pipe connects the outlet at the top of the reaction zone of the wetland system to the outlet tank, forming a vertical flow circulation path.

[0023] Start the peristaltic pump and adjust the flow rate so that the wastewater to be treated continuously enters the support area from the inlet tank through the inlet pipe, and is evenly distributed upward through the support area into the reaction area;

[0024] During operation, the pH value, oxidation-reduction potential and dissolved oxygen concentration inside the reaction zone are monitored in real time through in-situ detection columns; the hydraulic retention time is controlled at 3 to 5 days to ensure that the wastewater is in full contact with the manganese-rich granular packing material, thereby achieving simultaneous enhancement of ammonia oxidation and phosphorus adsorption.

[0025] The purified wastewater flows from the outlet at the top of the reaction zone through the outlet pipe into the outlet bucket, and is eventually discharged into natural water bodies.

[0026] The beneficial effects of this invention include:

[0027] The system of this invention uses a manganese matrix-enhanced ammonia oxidation and phosphorus adsorption process to achieve enhanced removal of nitrogen and phosphorus pollutants, further effectively improving the pollutant removal capacity of the constructed wetland system, and the effluent quality can stably meet the Class V water standard of China's surface water environment.

[0028] Manganese-based enhanced ammonia oxidation and phosphorus adsorption constructed wetland devices have a relatively simple structure and are easy to build. Furthermore, they do not have any special requirements for the device during the removal of nitrogen and phosphorus from wastewater, which can effectively reduce operating costs. Attached Figure Description

[0029] Figure 1 This is a structural diagram of the artificial wetland system for enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particle matrix, as described in this invention.

[0030] Figure 2 This is the chromatogram of Example 1 after 0h;

[0031] Figure 3 The chromatogram is shown in Example 1 after 0.5 hours.

[0032] Figure 4 The chromatogram is shown in Example 1 after 1 hour.

[0033] Figure 5 The chromatogram is shown in Example 1 after 1.5 hours.

[0034] Figure 6 This is the chromatogram of Example 1 after 2 hours;

[0035] Figure 7 The chromatogram is shown in Example 1 after 2.5 hours.

[0036] Figure 8 This is the chromatogram of Example 1 after 3 hours;

[0037] Figure 9 This is the chromatogram of Example 2 after 0h;

[0038] Figure 10 The chromatogram is shown in Example 2 after 0.5 hours.

[0039] Figure 11 This is the chromatogram of Example 2 after 1 hour;

[0040] Figure 12 The chromatogram is shown in Example 2 after 1.5 hours.

[0041] Figure 13 This is the chromatogram of Example 2 after 2 hours;

[0042] Figure 14 The chromatogram is shown in Example 2 after 2.5 hours.

[0043] Figure 15 This is the chromatogram of Example 2 after 3 hours;

[0044] Figure 16 This is the chromatogram of Example 3 after 0h;

[0045] Figure 17 The chromatogram is shown in Example 3 after 0.5 hours.

[0046] Figure 18 This is the chromatogram of Example 3 after 1 hour;

[0047] Figure 19 The chromatogram is shown in Example 3 after 1.5 hours.

[0048] Figure 20 This is the chromatogram of Example 3 after 2 hours;

[0049] Figure 21 The chromatogram is shown in Example 3 after 2.5 hours.

[0050] Figure 22 This is the chromatogram of Example 3 after 3 hours;

[0051] Figure 23 This is the chromatogram of the comparative example after 0 hours;

[0052] Figure 24 The chromatogram for the comparative example is shown after 0.5 hours.

[0053] Figure 25 This is the chromatogram of the comparative example after 1 hour;

[0054] Figure 26 The chromatogram for the comparative example is shown after 1.5 hours.

[0055] Figure 27 This is the chromatogram of the comparative example after 2 hours;

[0056] Figure 28 The chromatogram for the comparative example is shown after 2.5 hours.

[0057] Figure 29 This is the chromatogram of the comparative example after 3 hours;

[0058] In the diagram, 1-water inlet tank; 2-water inlet pipe; 3-peristaltic pump; 4-water inlet; 5-main body of wetland system; 6-wetland plants; 7-in-situ detection column; 8-pH monitor probe; 9-substrate sampling port; 10-water sampling port; 11-13: manganese-rich granular substrates of different particle sizes; 14-water outlet; 15-water outlet pipe; 16-water outlet tank. Detailed Implementation

[0059] The accompanying drawings are for illustrative purposes only. Directional terms such as "up," "down," "left," "right," "inner," "outer," and "side" in the drawings are merely illustrative based on the drawings and do not represent actual locations. The technical solution of the present invention will be fully and thoroughly described below in conjunction with the accompanying drawings and embodiments.

[0060] Constructed wetland technology has been widely used in wastewater pollution control in recent years due to its high efficiency, low cost, and significant ecological benefits. Constructed wetland systems are wastewater treatment facilities built on the ground. They leverage the synergistic effects of biological, physical, and chemical processes within natural ecosystems to achieve efficient wastewater purification through adsorption, filtration, ion exchange, plant absorption, and microbial decomposition. The substrate, as the core carrier of microorganisms within the constructed wetland system, plays a direct and indirect regulatory role in the water purification process, significantly influencing the structure and abundance of the microbial community. Notably, manganese substrates possess multiple functions: they act as electron acceptors or donors, providing crucial support for microbial growth, reproduction, and metabolic activities; they also serve as electron conduction mediators, facilitating extracellular electron transfer between microorganisms; furthermore, manganese substrates are highly efficient adsorption carriers for both inorganic and organic phosphorus, with active sites such as hydroxyl groups and oxygen vacancies on their surface achieving strong adsorption and fixation of phosphates through complexation and precipitation.

[0061] Reference Figure 1 This application provides an artificial wetland system for enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particle matrix. The system includes:

[0062] The main body 5 of a vertical subsurface flow type wetland system includes a support area and a reaction area arranged above the support area;

[0063] The bottom of the support area is provided with a water inlet 4, the top side wall of the reaction area is provided with a water outlet 14, and the reaction area is filled with manganese-rich granular filler. Wetland plants 6 are planted at the top opening of the reaction area.

[0064] The manganese-rich particle filler is a composite of quartz sand layer and manganese oxide, which is prepared by coating manganese oxide onto quartz sand.

[0065] The inlet 4 is connected to the inlet tank 1 via the peristaltic pump 3, and the outlet 14 is connected to the outlet tank 16.

[0066] Among them, reference Figure 1 The manganese-rich particle packing, from top to bottom, consists of the first manganese-rich particle packing 11, the second manganese-rich particle packing 12, and the third manganese-rich particle packing 13; the quartz sand in the manganese-rich particle packing is filled in layers, from bottom to top as follows:

[0067] Coarse quartz sand layers with a height between 0 and 15 cm and a particle size between 4 and 8 mm.

[0068] Medium-sized quartz sand layers with a height between 15 and 35 cm and a particle size between 2 and 4 mm.

[0069] A layer of fine quartz sand with a height between 35 and 55 cm and a particle size between 1 and 2 mm.

[0070] The manganese oxide is at least one of manganese dioxide, manganese trioxide, or manganese tetroxide, and its powder particle size is 0.45 μm.

[0071] The sidewalls of the reaction zone are uniformly provided with multiple matrix sampling ports 9 and multiple water sampling ports 10 from bottom to top.

[0072] The roots of the wetland plants are located at the height of the outlet 14.

[0073] An in-situ detection column 7 is set in the center of the reaction zone, and the top of the in-situ detection column 7 is higher than the top opening of the reaction zone;

[0074] The in-situ detection column 7 has multiple through holes on its side wall that connect its inner and outer walls.

[0075] The in-situ detection column 7 is equipped with a pH monitoring probe 8 and a redox potential and dissolved oxygen monitoring probe.

[0076] The system operates as follows: The inlet tank 1, peristaltic pump 3, and wetland system body 5 are connected sequentially via an inlet pipe, which is securely connected to the inlet 4 of the bottom support area. Simultaneously, the outlet 14 at the top of the reaction zone is connected to the outlet tank 16 via an outlet pipe, creating a complete vertical flow circulation path. The flow rate of peristaltic pump 3 is adjusted to ensure that the wastewater to be treated continuously enters the support area from the inlet tank 1 through the inlet pipe and flows evenly upwards into the reaction zone. During operation, the pH value, oxidation-reduction potential (ORP), and dissolved oxygen (DO) concentration inside the reaction zone are monitored using an in-situ detection column 7, and the hydraulic retention time is controlled between 3 and 5 days to ensure sufficient contact and deep degradation of nitrogen and phosphorus pollutants. The purified wastewater flows from the outlet 14 of the reaction zone through the outlet pipe into the outlet tank 14 and is discharged into a natural water body.

[0077] Example 1:

[0078] like Figure 1 As shown in the embodiment of this application, an constructed wetland system for enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particle matrix is ​​provided, comprising: a vertically flowing wetland system body 5. The wetland system body 5 is treated from top to bottom by injecting a manganese oxide suspension through a quartz sand matrix. Approximately 10 L of a 10 g / L manganese dioxide suspension is prepared and injected into the constructed wetland system at a flow rate of 200 ml / min. The effluent is collected and reinjected into the constructed wetland system at the same flow rate. Five cycles are performed. An inlet 4 is provided on the side of the cylindrical area. The top opening of the reaction zone is used for planting wetland plants 6; an outlet 14 is provided on the side wall of the reaction zone near the top opening. The roots of the wetland plants 6 are flush with the area above and below the outlet 14.

[0079] Reference Figure 1 The sidewall of the reaction zone is uniformly provided with a row of water sample sampling ports 10 from bottom to top, and three water sample sampling ports 10 are uniformly provided; the sidewall of the reaction zone is uniformly provided with a row of filter media sampling ports 9 from bottom to top, and three filter media sampling ports 9 are uniformly spaced.

[0080] Reference Figure 1 An in-situ detection column 7 is set in the center of the reaction zone. The top of the in-situ detection column 7 is higher than the top opening of the reaction zone. The in-situ detection column 7 is a PVC pipe with several small holes evenly distributed on it. The pH monitor probe, the oxidation-reduction potential and dissolved oxygen monitor probe can be inserted into the in-situ detection column 7 for monitoring.

[0081] Reference Figure 1 The inlet 4 of the wetland system body 5 is connected to the inlet tank 1 via a peristaltic pump 3, and its outlet 14 is connected to the outlet tank 16 via an outlet pipe 15.

[0082] The first manganese-rich particle 11 and the second manganese-rich particle 12 are prepared by coating manganese oxide powder with a particle size of 0.45 micrometers onto quartz sand, which can promote the release of manganese, promote plant root growth, and enhance the nitrogen and phosphorus removal process.

[0083] The operation method of an constructed wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich granular matrix includes the following steps:

[0084] (1) Connect the water inlet tank 1, peristaltic pump 3, and wetland system body 5 through the water inlet pipe 2, and connect the water inlet pipe 2 to the water inlet 4; connect the wetland system body 5 and the water outlet tank 16 through the water outlet pipe 15.

[0085] (2) The constructed wetland system provided in this embodiment is started by inoculating anaerobic sludge from a municipal wastewater treatment plant. The Class A effluent from the municipal wastewater treatment plant is used as the wetland system influent, mainly containing ammonia nitrogen (5.11±0.04 mg / L), nitrate (10.14±0.03 mg / L), and phosphate (0.49±0.01 mg / L). The peristaltic pump 3 is started, and wastewater enters the main body 5 of the wetland system from the influent tank 1 through the influent pipe 2. The influent flow is continuous. After being supported by filter media, it enters the reaction zone, where nitrogen and phosphorus pollutants are removed from bottom to top by passing through the first manganese-rich particles 13, the second manganese-rich particles 12, and the first manganese-rich particles 11, which release manganese. The specific method is as follows:

[0086] In the lower part of the reaction zone, wastewater enters through inlet 4 and undergoes a preliminary ammonia oxidation reaction using some dissolved oxygen introduced from the influent. This process consumes dissolved oxygen and converts some ammonia nitrogen into nitrate. In the middle of the reaction zone, as dissolved oxygen is consumed, the system enters an anoxic state. At this point, high-valence manganese oxides (such as manganese dioxide) coated on the surfaces of the first and second manganese-rich particles 11 and 12 act as endogenous electron acceptors, driving the anoxic ammonia oxidation process. This directly converts ammonia nitrogen into nitrite or nitrogen gas, achieving enhanced nitrogen removal under anoxic conditions. In the upper part of the reaction zone, divalent manganese ions generated during the manganese ammonia oxidation process, along with manganese elements slowly released from the manganese-rich matrix, undergo coordination complexation and chemical precipitation with phosphates in the water, achieving deep adsorption and in-situ fixation of phosphorus. Simultaneously, the released manganese elements, as essential micronutrients for plant growth, are absorbed by wetland plants, promoting deeper root growth and enhancing root oxygen secretion capacity, forming multiple micro-oxygen zones around the rhizosphere. These micro-oxygen zones not only further oxidize residual ammonia nitrogen, but also maintain the continuous reactivity of the matrix by promoting the cyclic oxidation of manganese (re-oxidizing divalent manganese to higher-valent manganese oxides).

[0087] The purified wastewater flows from the outlet 14 of the reaction zone through the outlet pipe 15 into the outlet tank 16 and is discharged into the natural water body. The ammonia nitrogen content of the effluent through the outlet 14 is 2.57±0.12mg / L, the nitrate content is 4.00±0.50mg / L, the phosphate content is 0.11±0.01mg / L, and the manganese ion content is 0.14±0.02mg / L.

[0088] Due to the slow water flow and relatively insufficient dissolved oxygen, ammonia nitrogen removal is primarily achieved through anoxic ammonia oxidation driven by manganese-rich particles. Furthermore, manganese ions can participate in de-ammonia oxidation, resulting in a low effluent concentration that avoids heavy metal pollution and provides significant ecological benefits. In addition to treating effluent from municipal wastewater treatment plants, this system can also be flexibly applied to treat secondary biological wastewater from urban sewage treatment plants, low C / N ratio industrial wastewater, or polluted landscape water bodies. In practical engineering applications, key process parameters such as hydraulic retention time (HRT), influent load, and operating cycle can be adjusted and optimized according to different influent water qualities and target effluent standards.

[0089] Reference Figures 2-8 Gas chromatograms obtained using an electron capture detector (ECD) were analyzed. Based on the chromatograms and peak tables, distinct peaks appeared at retention times of approximately 5 minutes at 0h, 0.5h, 1h, 1.5h, 2h, 2.5h, and 3h. These peaks were identified as N₂O, with quantitative concentrations of 0.899 ppm, 0.924 ppm, 0.939 ppm, 0.970 ppm, 0.997 ppm, 1.019 ppm, and 1.055 ppm, respectively. The calculated N₂O emission flux was 26.76 μg / m² / h, indicating that manganese dioxide effectively promotes the ammonia oxidation process and generates the gaseous intermediate product N₂O. The N₂O concentration showed a stable increasing trend with increasing reaction time, indicating that manganese dioxide has good sustained catalytic activity in this system.

[0090] Example 2:

[0091] The approximately 10L manganese-rich colloidal (manganese dioxide) slurry with a concentration of 10g / L prepared in Example 1 was replaced with approximately 10L manganese-rich colloidal (manganese trioxide) slurry with a concentration of 10g / L, while other conditions remained the same as in Example 1.

[0092] The purified wastewater flows from the outlet 14 of the reaction zone through the outlet pipe 15 into the outlet tank 16 and is discharged into the natural water body. The ammonia nitrogen content of the effluent through the outlet 14 is 2.32±0.17mg / L, the nitrate content is 3.73±0.46mg / L, the phosphate content is 0.08±0.00mg / L, and the manganese ion content is 0.23±0.02mg / L.

[0093] Reference Figures 9-15Gas chromatograms obtained using an electron capture detector (ECD) were analyzed. Based on the chromatograms and peak tables, distinct chromatographic peaks appeared at retention times of approximately 5 minutes at 0h, 0.5h, 1h, 1.5h, 2h, 2.5h, and 3h. These peaks were identified as N₂O, with quantitative concentrations of 0.905 ppm, 0.921 ppm, 0.934 ppm, 0.955 ppm, 0.972 ppm, 0.983 ppm, and 1.006 ppm, respectively. The calculated N₂O emission flux was 18.54 μg / m³. 2 The concentration of N2O was measured at a rate of / h, indicating that manganese trioxide can effectively promote the ammonia oxidation process and generate the gaseous intermediate N2O. The N2O concentration showed a stable increasing trend with prolonged reaction time, demonstrating that manganese trioxide has good and sustained catalytic activity in this system.

[0094] Example 3:

[0095] The approximately 10L manganese-rich colloidal (manganese dioxide) slurry with a concentration of 10g / L prepared in Example 1 was replaced with approximately 10L manganese-rich colloidal (manganese tetroxide) slurry with a concentration of 10g / L, while other conditions remained the same as in Example 1.

[0096] The purified wastewater flows from the outlet 14 of the reaction zone through the outlet pipe 15 into the outlet tank 16 and is discharged into the natural water body. The ammonia nitrogen content of the effluent from the outlet 14 is 1.69±0.26mg / L, the nitrate content is 4.07±0.52mg / L, the phosphate content is 0.20±0.01mg / L, and the manganese ion content is 0.36±0.04mg / L.

[0097] Reference Figures 16-22 Gas chromatograms obtained using an electron capture detector (ECD) were analyzed. Based on the chromatograms and peak tables, distinct peaks appeared at retention times of approximately 5 minutes at 0h, 0.5h, 1h, 1.5h, 2h, 2.5h, and 3h. These peaks were identified as N₂O, with quantitative concentrations of 0.903 ppm, 0.905 ppm, 0.908 ppm, 0.917 ppm, 0.923 ppm, 0.929 ppm, and 0.936 ppm, respectively. The calculated N₂O emission flux was 6.46 μg / m³. 2 The concentration of N₂O / h indicates that manganese tetroxide can effectively promote the ammonia oxidation process and generate the gaseous intermediate product N₂O. The N₂O concentration shows a stable increasing trend with prolonged reaction time, indicating that manganese tetroxide has good and sustained catalytic activity in this system.

[0098] Comparative Example 1:

[0099] The manganese-rich particles in the reaction zone of Example 1 were replaced with quartz sand, and other conditions were the same as in Example 1.

[0100] The evolved wastewater flows from the outlet 14 of the reaction zone through the outlet pipe 15 into the outlet tank 16 and is discharged into the natural water body. The ammonia nitrogen content of the effluent through the outlet 14 is 3.03±0.08mg / L, the nitrate content is 4.00±0.50mg / L, and the phosphate content is 0.49±0.01mg / L.

[0101] Reference Figures 23-29 Gas chromatograms obtained using an electron capture detector (ECD) were analyzed. Based on the chromatograms and peak tables, distinct chromatographic peaks appeared at retention times of approximately 5 minutes at 0h, 0.5h, 1h, 1.5h, 2h, 2.5h, and 3h. These peaks were identified as N₂O, with quantitative concentrations of 0.822 ppm, 0.878 ppm, 0.912 ppm, 0.933 ppm, 0.954 ppm, 0.973 ppm, and 0.989 ppm, respectively. The calculated N₂O emission flux was 29.22 μg / m³. 2 The concentrations per hour ( / h) are higher than those of the system using manganese-loaded silica sand, indicating that manganese-free silica sand also undergoes an ammonia oxidation process and generates gaseous intermediate product N2O, but the N2O emission reduction effect is poor.

[0102] In the description of this invention, unless otherwise expressly specified and limited, the terms "installation", "connection", "linking", etc., should be interpreted broadly, and those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0103] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. An artificial wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich granular matrix, characterized in that, The system includes: The main body (5) of the vertical subsurface flow type wetland system includes a support area and a reaction area arranged above the support area; The bottom of the support area is provided with an inlet (4), the top side wall of the reaction area is provided with an outlet (14), and the reaction area is filled with manganese-rich particle filler, and wetland plants (6) are planted at the top opening of the reaction area. The manganese-rich particle filler is a composite of quartz sand layer and manganese oxide, which is prepared by coating manganese oxide onto quartz sand. The inlet (4) is connected to the inlet tank (1) via the peristaltic pump (3), and the outlet (14) is connected to the outlet tank (16).

2. The constructed wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particle matrix according to claim 1, characterized in that, The quartz sand in the manganese-rich granular filler is filled in layers, from bottom to top as follows: Coarse quartz sand layers with a height between 0 and 15 cm and a particle size between 4 and 8 mm. Medium-sized quartz sand layers with a height between 15 and 35 cm and a particle size between 2 and 4 mm. A layer of fine quartz sand with a height between 35 and 55 cm and a particle size between 1 and 2 mm.

3. The constructed wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particle matrix according to claim 1, characterized in that, The manganese oxide is at least one of manganese dioxide, manganese trioxide, or manganese tetroxide, and its powder particle size is 0.45 μm.

4. The constructed wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particle matrix according to claim 1, characterized in that, The sidewalls of the reaction zone are uniformly provided with multiple matrix sampling ports and multiple water sampling ports from bottom to top.

5. The constructed wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particle matrix according to claim 1, characterized in that, The roots of the wetland plants are located at the height of the outlet (14).

6. The constructed wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich particle matrix according to claim 1, characterized in that, An in-situ detection column (7) is set in the center of the reaction zone, and the top of the in-situ detection column (7) is higher than the top opening of the reaction zone; The in-situ detection column (7) has multiple through holes on its side wall that connect its inner and outer walls; The in-situ detection column (7) is equipped with a pH monitoring probe, an oxidation-reduction potential and dissolved oxygen monitoring probe.

7. A method for wastewater treatment using an artificial wetland system with enhanced ammonia oxidation and phosphorus adsorption using a manganese-rich granular matrix as described in any one of claims 1-6, characterized in that, Includes the following steps: The inlet pipe (2) connects the inlet bucket (1), the peristaltic pump (3) to the inlet (4) at the bottom of the wetland system body (5) in sequence; the outlet pipe (15) connects the outlet (14) at the top of the reaction zone of the wetland system body (5) to the outlet bucket (16) to form a vertical flow circulation path. Start the peristaltic pump (3) and adjust the flow rate so that the wastewater to be treated continuously enters the support area from the inlet tank (1) through the inlet pipe (2), and is evenly distributed upward through the support area to enter the reaction area; During operation, the pH value, oxidation-reduction potential and dissolved oxygen concentration inside the reaction zone are monitored in real time by the in-situ detection column (7); the hydraulic retention time is controlled to be 3 to 5 days so that the sewage can fully contact the manganese-rich granular packing material and achieve simultaneous enhancement of ammonia oxidation and phosphorus adsorption. The purified wastewater flows from the outlet (14) at the top of the reaction zone through the outlet pipe (15) into the outlet bucket (16) and is eventually discharged into the natural water body.

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