A composite subsurface flow wetland system based on oxygen-supplementing matrix structure

Abstract

A composite subsurface wetland system based on an oxygen-supplementing matrix structure includes a downstream subsurface flow area, an upstream subsurface flow area, and a deep treatment and purification area. The oxygen-supplementing matrix structure is laid in the subsurface flow area, and numerous ellipsoidal matrix bodies (3) are neatly and regularly placed in a matrix block frame to form an oxygen-supplementing matrix structure (4). The ellipsoidal matrix body is in the shape of an ellipsoid, and is divided into an upper hemisphere (white body) as a hollow body and a lower hemisphere (black body) as a matrix. In the deep treatment and purification area, water flows from the upstream subsurface flow area into the front area (deep pool area) in a waterfall-like manner, thereby forming an aerobic aeration treatment effect; the water body flows horizontally from the front area (deep pool area) to the rear area (shallow beach area), thereby forming an ecological deep treatment effect. The composite subsurface wetland system based on the oxygen-supplementing matrix structure of the present invention has good sewage purification effect, sufficient oxygenation, improved sewage treatment effect, simple structure and easy maintenance and management.

Description

Technical Field

[0001] The invention relates to a composite subsurface flow wetland system based on an oxygen-supplementing matrix structure, belonging to the technical field of wastewater treatment. Background Art

[0002] The research and development of sewage treatment technologies and techniques is a continuous process of advancement. With the continuous improvement and development of sewage treatment techniques or technologies, the limitations of traditional biological and ecological methods in terms of time and space have become apparent.

[0003] Constructed wetlands are artificial ecosystems built to simulate natural wetlands. Since the 1980s, they have been widely used in research on the purification of various polluted water bodies. Their efficient removal of wastewater pollutants and economical operation have led to their widespread application. Compared with other wastewater treatment processes, constructed wetlands offer numerous advantages: stable effluent, low construction and operating costs, simple maintenance, high treatment efficiency, wide applicability, and strong adaptability to load fluctuations. Vertical subsurface flow wetlands are currently the most commonly used type of constructed wetland.

[0004] A vertical subsurface flow wetland system utilizes hydrophilic plants as surface greenery and a matrix of various filler materials. Sewage enters through the water distribution area at the front of the vertical subsurface flow wetland, undergoes treatment and purification within the wetland system, and is finally discharged at the end of the system. Within the vertical subsurface flow wetland system, sewage flows internally, leveraging the biofilms grown on the substrate, the rich root systems of the plants, and the surface matrix for interception, improving its treatment efficiency and capacity. Furthermore, because the water flows below the surface, it provides excellent thermal insulation, is less affected by climate, and provides better sanitary conditions.

[0005] Existing vertical subsurface flow wetlands face issues with oxygenation during operation. Insufficient oxygenation is a major obstacle to the long-term operation of wetland systems, severely impacting their wastewater purification effectiveness. This oxygen deficiency deteriorates the physical and chemical environment, leading to a decrease in microbial activity and ultimately a further slowdown in pollutant degradation.

[0006] There is still a lack of effective solutions to the problems of insufficient oxygenation in artificial wetlands in the existing technology. Summary of the Invention

[0007] The purpose of the present invention is to solve the problem of insufficient oxygenation in artificial wetlands and propose a composite subsurface flow wetland system based on an oxygen-supplementing matrix structure.

[0008] The technical solution implemented by the present invention is as follows: a composite subsurface flow wetland system based on an oxygen-supplementing matrix structure, comprising a downward subsurface flow area, an upward subsurface flow area and a deep treatment and purification area.

[0009] The downward undercurrent zone and the upward undercurrent zone are both filled with an oxygen-supplementing matrix structure; the oxygen-supplementing matrix structure is composed of a rectangular frame made of plastic material and an ellipsoidal matrix body housed in the frame; the ellipsoidal matrix body is made of polypropylene (PVC) plastic in an ellipsoidal shape, and is composed of two ellipsoidal hemispheres to form an ellipsoidal sphere, the upper hemisphere is a white body, and the white body is a hollow shell; the lower hemisphere is a black body, and the black body is a hollow body, each black body hollow shell hemisphere has 6 strip-shaped gaps, and the shell is filled with biological ceramsite matrix; the white body and the black body are rotated together or separated through a spiral mouth in the middle of the long axis direction; air enters and exits the white body shell through the hollow gap of the hollow shell, and water enters and exits the black body through the hollow structure, and then the oxygen-supplementing matrix structure adsorbs and treats the water.

[0010] In the oxygen-supplementing matrix structure, each frame is provided with two layers of ellipsoidal matrix bodies, each layer is provided with two rows of ellipsoidal matrix bodies, and each row is provided with 10 ellipsoidal matrix bodies. The oxygen-supplementing matrix structure fixes the ellipsoidal matrix bodies and is convenient for replacing the ellipsoidal matrix bodies.

[0011] The six sides of the frame are evenly distributed with circular holes, and the diameter of the circular holes is smaller than the maximum cross-sectional diameter of the ellipsoidal matrix in the long axis direction.

[0012] The downward underflow zone, the upward underflow zone and the deep treatment and purification zone are all rectangular, and the length ratio of the three zones is 1:1:1.

[0013] In the downward undercurrent zone, water inlet pipes are evenly distributed on the surface, yellow iris is planted on the surface, and the oxygen-supplementing matrix structure fills the downward undercurrent zone; water enters the upward undercurrent zone through the connecting water pipe between the downward undercurrent zone and the upward undercurrent zone.

[0014] In the upward undercurrent zone, yellow iris is planted on the surface, and the oxygen-supplementing matrix structure fills the upward undercurrent zone; outlet pipes are evenly arranged in the upward undercurrent zone, and water enters the deep treatment and purification zone through the outlet pipes.

[0015] The deep treatment and purification area consists of a front area (deep pool area) and a back area (shallow area), with a length ratio of 1:1. The front area (deep pool area) uses shale ceramsite with large particle size and high porosity as the matrix; the back area (shallow area) is planted with foxtail algae.

[0016] The front area (deep pool area) uses shale expanded clay with larger particle size and high porosity as the matrix, and the rear area (shallow beach area) is planted with foxtail algae; the front area (deep pool area) uses shale expanded clay as the matrix, which can not only absorb pollutants such as nitrogen and phosphorus in the water body, but also serve as an attachment site for aerobic microorganisms for aerobic treatment; after the water body is treated in the front area (deep pool area), it flows through the rear area (shallow beach area) for further treatment.

[0017] The present invention solves the existing problems of insufficient oxygenation capacity in subsurface flow wetlands, offering advantages such as a simple structure and the ability to improve the oxygenation capacity of subsurface flow wetlands. The present invention utilizes an ellipsoidal matrix for oxygenation, combined with conventional vertical subsurface flow wetland system aerobic wastewater treatment technology, to significantly improve the wetland's oxygenation capacity. The oxygen-supplementing vertical subsurface flow wetland system of the present invention offers the advantages of effective wastewater purification, strong oxygenation capacity, and long-term stable operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The figure shows the structure of the composite subsurface flow wetland system based on oxygen-supplementing matrix structure of the present invention;

[0019] Figure 2 Schematic diagram of the structure of the oxygen-supplementing matrix construct;

[0020] Figure 3 Schematic diagram of the structure of the ellipsoidal matrix;

[0021] The three areas from left to right in the figure are the downward underflow area, the upward underflow area, and the deep treatment and purification area.

[0022] Figure numbers in the figure: 1 is the water distribution area of ​​the downward vertical undercurrent zone, water inlet; 2 is the surface planted plant, yellow calamus; 3 is the ellipsoidal matrix body; 4 is the oxygen-supplementing matrix structure; 5 is the connecting water pipe between the downward undercurrent zone and the upward undercurrent zone; 6 is the fill; 7 is the timed drainage pipe arranged at the connection between the bottom of the upward undercurrent zone and the front zone (deep pool zone); 8 is the outlet pipe from the upward undercurrent zone to the deep treatment and purification zone; 9 is the waterfall-like water body from the upward undercurrent zone to the front zone (deep pool zone); 10 is the matrix of the front zone (deep pool zone), shale ceramsite; 11 is the planted plant in the back zone (shallow zone), foxtail algae; 12 is the frame; 31 is the white body; 32 is the black body. DETAILED DESCRIPTION

[0023] The specific embodiments of the present invention are as follows Figure 1 shown.

[0024] The entire sewage treatment process of the oxygen-replenishing composite subsurface flow wetland system shows that, after pretreatment, the sewage enters the wetland system through the water distribution area inlet pipe 1 in the downward vertical subsurface flow zone. The surface plants of the water distribution zone, Iris calamus 2, absorb and degrade pollutants in the sewage and intercept impurities in the sewage. The plants absorb pollutants such as nitrogen and phosphorus in the sewage, grow and reproduce, and are mowed when they reach a certain size.

[0025] The sewage flows through the plants on the surface of the water distribution area in the downward vertical subsurface flow zone to the oxygen-supplementing matrix structure 4 in the downward vertical subsurface flow zone; the ellipsoidal matrix body 3 in the oxygen-supplementing matrix structure and the microorganisms attached to the ellipsoidal matrix body remove nitrogen, phosphorus, organic matter and other pollutants in the sewage through a series of physical, chemical and biological pathways such as absorption, adsorption, filtration, ion exchange and complexation reaction.

[0026] The oxygen-supplementing matrix structure of this embodiment is composed of a rectangular plastic frame and an ellipsoidal matrix body inside; the ellipsoidal matrix body is an ellipsoidal structure made of polypropylene (PVC) plastic. The size of the ellipsoidal matrix body (the major and minor axes of the ellipse) is defined as: the major axis of the ellipse: the minor axis is equal to 1:0.618, and the designed major axis is 15 cm.

[0027] The fixed matrix structure of the present embodiment is limited to a frame having a length of 92.7 cm, a width of 18.54 cm, and a height of 30 cm. The frame is evenly provided with circular holes on all six sides, the diameter of the circular holes being smaller than the maximum cross-sectional diameter (i.e., the cross-sectional diameter at the midpoint of the long axis) of the ellipsoidal matrix.

[0028] The ellipsoidal matrix body is composed of two elliptical hemispheres to form an ellipsoidal structure. The upper hemisphere is a white body, which is a hollow shell; the lower hemisphere is a black body, which is a hollow body. Each black body hollow shell hemisphere has 6 strip-shaped gaps, and the shell is filled with biological ceramsite matrix; the white body and the black body are combined or separated by a spiral mouth in the middle of the long axis direction; air enters and exits the white body shell through the hollow gaps of the hollow shell, and water enters and exits the black body through the hollow structure, and then the oxygen-supplementing matrix structure adsorbs and treats the water.

[0029] The downward underflow zone, the upward underflow zone and the deep treatment and purification zone of this embodiment are all rectangular, and the length ratio of the three zones is 1:1:1.

[0030] In the downward undercurrent zone of this embodiment, water inlet pipes are evenly distributed on the surface, yellow calamus is planted on the surface, and the oxygen-supplementing matrix structure fills the downward undercurrent zone; water enters the upward undercurrent zone through the connecting water pipe between the downward undercurrent zone and the upward undercurrent zone.

[0031] In the upward underflow area of ​​this embodiment, yellow iris is planted on the surface, and the oxygen-supplementing matrix structure fills the upward underflow area; outlet pipes are evenly arranged in the upward underflow area, and water enters the deep treatment and purification area through the outlet pipes.

[0032] The deep treatment and purification zone in this embodiment consists of a front zone (deep pool) and a back zone (shallows), with a length ratio of 1:1. The front zone (deep pool) uses shale ceramsite with large particle size and high porosity as its substrate, while the back zone (shallows) is planted with Myriophyllum.

[0033] In the front area (deep pool area) of this embodiment, shale ceramsite with larger particle size and higher porosity is used as a matrix, and the plant Myriophyllum is planted in the rear area (shallow beach area); the shale ceramsite in the front area (deep pool area) can not only absorb pollutants such as nitrogen and phosphorus in the water body, but also serve as an attachment site for aerobic microorganisms to carry out aerobic treatment; after the water body is treated in the front area (deep pool area), it flows through the rear area (shallow beach area) for further treatment.

[0034] In the composite subsurface flow wetland system based on the oxygen-supplementing matrix structure of this embodiment, a temporary drainage pipe is arranged at the connection between the bottom of the upward subsurface flow area and the front area (deep pool area).

[0035] In the upward underflow area, sewage passes through the ellipsoidal matrix bodies in the oxygen-supplementing matrix structure and the microorganisms attached to the ellipsoidal matrix bodies, and removes nitrogen, phosphorus, organic matter and other pollutants in the sewage through a series of physical, chemical and biological pathways such as absorption, adsorption, filtration, ion exchange and complexation reaction.

[0036] Pollutants in the sewage are then absorbed and degraded by the yellow iris plants on the surface of the upward underflow zone. The plants absorb nitrogen, phosphorus and other pollutants in the sewage, grow and reproduce, and are mowed when they reach a certain size.

[0037] In the ellipsoidal matrix bodies in the downward and upward underflow zones, the matrix in the black body removes pollutants such as nitrogen, phosphorus, and organic matter from the sewage through a series of physical, chemical, and biological processes, such as absorption, adsorption, filtration, ion exchange, and complexation reactions. A large number of microorganisms then attach to the biological ceramsite in the black body, grow and reproduce, and biodegrade the pollutants in the sewage. During the degradation process, the air in the white body continuously oxygenates the water, providing sufficient oxygen for the microorganisms and performing aerobic treatment of the water.

[0038] Depending on the scale of sewage treatment, a timed drain pipe 7 is installed at the junction of the bottom of the ascending underflow zone and the front zone (deep pool). When the timed drain pipe is opened, sewage from both the descending and ascending underflow zones is drained and completely emptied, replenishing the air within the ellipsoidal matrix's white body, filling the entire white body space and providing oxygen for the microorganisms in the next sewage treatment process, thereby achieving aerobic treatment of the water body.

[0039] Sewage discharged through the timed drain pipes that has not been fully treated in the downstream and upstream underflow areas enters the deep treatment and purification area for full treatment. The deep treatment and purification area is set up to not only provide deep treatment for the sewage after treatment in the downstream and upstream underflow areas, but also to treat the sewage that has not been fully treated in the downstream and upstream underflow areas when the timed drain pipes are emptied.

[0040] When the sewage is emptied through the timed drain pipe, some biofilm and impurities in the sewage are produced in the downward and upward undercurrent areas, which are carried by the water body into the deep treatment and purification area and further absorbed and treated by the foxtail algae in the rear area (shallow area).

[0041] After the timed drain pipe has emptied the water in the downward undercurrent area and the upward undercurrent area, the timed drain pipe is closed.

[0042] In this embodiment, the water levels in the downward underflow zone and the upward underflow zone rise. During this process, the ellipsoidal matrix bodies in the downward underflow zone and the upward underflow zone are backwashed once, and the biofilm attached to the ellipsoidal matrix bodies is suspended in the water body and enters the deep treatment purification area when the water body is emptied next time.

[0043] As the water level rises and the water eventually fills the downward and upward undercurrent zones, the air pressure in the ellipsoidal matrix increases, and its oxygenation capacity for the water is stronger than that under standard atmospheric pressure, resulting in a higher dissolved oxygen concentration in the water and a higher aerobic treatment effect of the microorganisms on the sewage.

[0044] In this embodiment, the ellipsoidal matrix body fixed by the oxygen-supplementing matrix structure leaves more gaps between the downward underflow zone and the upward underflow zone, thereby improving the microbial habitat and enhancing the sewage treatment capacity of the microorganisms.

[0045] The sewage treated in the descending underflow area and the ascending underflow area enters the outlet pipe 8 of the deep treatment and purification area through the ascending underflow area, and enters the deep treatment and purification area in the form of a waterfall water body 9.

[0046] The water body falls into the front area (deep pool area) in a waterfall-like manner. The sewage is reoxygenated in this process. The sewage entering the front area (deep pool area) has a high dissolved oxygen content in the shale ceramsite 10 matrix bed, which provides a large amount of dissolved oxygen for aerobic microorganisms attached to the matrix bed. The aerobic microorganisms perform aerobic treatment on the sewage.

[0047] The water flows through the back area (shallow area), where the foxtail algae 11 plants absorb nitrogen, phosphorus and other substances in the sewage for deep treatment.

Claims

1. A composite subsurface flow wetland system based on an oxygen-supplementing matrix structure, comprising a downward subsurface flow area, an upward subsurface flow area and a deep treatment and purification area, characterized in that: The downward undercurrent zone and the upward undercurrent zone are both filled with an oxygen-supplementing matrix structure; the oxygen-supplementing matrix structure is composed of a rectangular frame made of plastic material and an ellipsoidal matrix body housed in the frame; the ellipsoidal matrix body is made of polypropylene plastic in an ellipsoidal sphere, and is composed of two ellipsoidal hemispheres to form an ellipsoidal sphere, the upper hemisphere is a white body, and the white body is a hollow shell; the lower hemisphere is a black body, and the black body is a hollow body, each black body hollow shell hemisphere has 6 strip-shaped gaps, and the shell is filled with a biological ceramsite matrix; the white body and the black body are rotatably combined or separated through a spiral mouth in the middle of the long axis direction; air enters and exits the white body shell through the hollow gap of the hollow shell, and water enters and exits the black body through the hollow structure, and then the oxygen-supplementing matrix structure performs adsorption treatment on the water body.

2. A composite subsurface flow wetland system based on an oxygen-supplementing matrix structure according to claim 1, characterized in that: In the oxygen-supplementing matrix structure, each frame is provided with two layers of ellipsoidal matrix bodies, each layer is provided with two rows of ellipsoidal matrix bodies, and each row is provided with 10 ellipsoidal matrix bodies.

3. A composite subsurface flow wetland system based on an oxygen-supplementing matrix structure according to claim 2, characterized in that: The six sides of the frame of the fixed ellipsoidal matrix are evenly distributed with circular holes, so that wastewater can flow in and out freely; the diameter of the circular holes is smaller than the maximum cross-sectional diameter of the ellipsoidal matrix in the long axis direction.

4. A composite subsurface flow wetland system based on an oxygen-supplementing matrix structure according to claim 1, characterized in that: The downward underflow zone, the upward underflow zone and the deep treatment and purification zone are all rectangular, and the length ratio of the three zones is 1:1:

1.

5. A composite subsurface flow wetland system based on an oxygen-supplementing matrix structure according to claim 4, characterized in that: In the downward undercurrent zone, water inlet pipes are evenly arranged on the surface, yellow calamus is planted on the surface, and the oxygen-supplementing matrix structure fills the downward undercurrent zone; water enters the upward undercurrent zone through the connecting water pipe between the downward undercurrent zone and the upward undercurrent zone; In the upward undercurrent zone, yellow iris is planted on the surface, and the oxygen-supplementing matrix structure fills the upward undercurrent zone; outlet pipes are evenly arranged in the upward undercurrent zone, and the water enters the deep treatment and purification zone through the outlet pipes; The deep treatment and purification area consists of a deep pool area and a shallow beach area, with a length ratio of 1:1; the deep pool area uses shale ceramsite with larger particle size and higher porosity as the matrix; the shallow beach area is planted with foxtail algae.

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