Bank slope type tail water purification system

Abstract

The bank slope type tail water purification system comprises an ecological retention area, an undercurrent wetland area, a step surface flow wetland area and an underwater forest area, the ecological retention area is sequentially provided with a plant fiber layer, a first planting soil layer, a coarse sand layer and a gravel layer from top to bottom, the undercurrent wetland area comprises a base, the top of the base is fixedly provided with a base, and the bottom of the base is fixedly provided with a second planting soil layer. A reinforced concrete purification pond is fixedly arranged at the top of the base, a water distribution area, a water collection area and a treatment area located between the water distribution area and the water collection area are formed in the reinforced concrete purification pond, the stepped surface flow wetland area comprises a first-stage surface flow wetland and a second-stage surface flow wetland, and a floating enclosure is fixedly arranged in the underwater forest area; according to the bank slope type tail water purification system, the bank slope space of a river channel is fully utilized, construction land is not occupied, the operation cost is low, the purification effect is good, and maintenance is easy and convenient; river flood discharge is not affected, bank slope stability is improved, and river aquatic organism recovery is facilitated.

Description

TECHNICAL FIELD

[0001] The utility model relates to tail water purification technical field, concretely is a bank slope formula tail water purification system. BACKGROUND

[0002] With the continuous promotion of water environment governance in China, most of the point source pollution and internal source pollution are controlled, the surface water environmental quality in China is continuously good, and the water quality of the river basin is obviously improved. Non-point source pollution becomes an important factor restricting the current river and lake water quality improvement in China, and non-point source pollution mainly includes rural domestic sewage, farmland runoff, aquaculture tail water and initial rainwater. Once non-point source pollution enters the river, it will have a great impact on the water quality of the surrounding water body.

[0003] Non-point source pollution has the characteristics of wide area, large quantity, low concentration of pollutants and uncertain production time, so the treatment of non-point source pollution is difficult. The ecological treatment method is used to effectively treat non-point source pollution, and the ecological treatment technology has the advantages of low investment, low energy consumption, stable effluent water quality and strong impact resistance, and is more suitable for non-point source pollution treatment. But the existing ecological treatment technology needs to occupy more land space, so the promotion is limited, for example, the treatment area of aquaculture tail water accounts for 5%-15% of the breeding area.

[0004] Generally, the river channel is provided with a land control range, for example, the land control range of small and medium-sized river channels in Shanghai is 6m outward from the river mouth line. The land control and bank slope range generally does not allow development, but these spaces can be used to appropriately build a pollution purification system. How to make full use of the effective space of the water body land control range and the river bank to purify non-point source pollution has become an important part of non-point source pollution treatment. UTILITARIAN CONTENT

[0005] The utility model aims at providing a bank slope formula tail water purification system to solve the problems in the above background technology.

[0006] To achieve the above purpose, the utility model provides the following technical scheme: a bank slope formula tail water purification system, including ecological retention area, undercurrent wetland area, gradient surface flow wetland area and underwater forest area, the ecological retention area, undercurrent wetland area, gradient surface flow wetland area and underwater forest area are arranged in sequence, non-point source pollution drainage passes through ecological retention area, undercurrent wetland area, gradient surface flow wetland area and underwater forest area in proper order, then enters the main river channel by overflow again;

[0007] The ecological retention area is sequentially provided with a plant fiber layer, a first planting soil layer, a coarse sand layer and a gravel layer from top to bottom, the bottom of the gravel layer is provided with an anti-seepage film, a water permeable pipe is arranged in the gravel layer, and the water permeable pipe is communicated with a first water outlet pipe extending out of the gravel layer; the surface source sewage is filtered layer by layer from the surface of the ecological retention area to the lower layer, collected in the water permeable pipe and discharged; after the treatment, most of the particulate pollutants in the sewage are removed, and a certain amount of nitrate nitrogen is formed under the oxidation condition;

[0008] The subsurface flow wetland area includes a base, a base is fixedly arranged on the top of the base, a reinforced concrete purification tank is fixedly arranged on the top of the base, the reinforced concrete purification tank is provided with a water distribution area, a water collection area and a treatment area between the water distribution area and the water collection area, one end of one side of the reinforced concrete purification tank is provided with a first water inlet pipe communicated with the water distribution area, the middle of the other side of the reinforced concrete purification tank is provided with a second water outlet pipe communicated with the water collection area, two concrete plates are arranged in the treatment area, the treatment area is divided into three beds by the two concrete plates, gravel layers and pebble layers are sequentially arranged in the three beds from top to bottom, water distribution pipes communicated with the water distribution area are arranged in the pebble layers, water collection pipes communicated with the water collection area are arranged in the gravel layers, the sewage first enters the water distribution area through the first water inlet pipe, is uniformly distributed to the bottom of the three beds of the treatment area through the water distribution pipes, flows from the bottom to the top, flows through the pebble layers and the gravel layers, and after a period of time, a biological membrane is formed on the surface of the pebble layers and the gravel layers, the microbial biological membrane absorbs soluble organic pollutants in the sewage as nutrients required for its physiological activities, and the organic pollutants are decomposed in the metabolism process, the sewage enters the water collection area through the water collection pipes on the surface of the bed, and enters the cascade surface flow wetland area through the second water outlet pipe;

[0009] The cascade surface flow wetland area includes a first level surface flow wetland and a second level surface flow wetland, a second water inlet pipe is arranged on the top of one side of the first level surface flow wetland, and the first level surface flow wetland and the second level surface flow wetland are sequentially provided with a volcanic rock layer and a second planting soil layer from top to bottom; the cascade surface flow wetland area is not provided with water distribution pipes and water collection pipes, and the water flow flows in the cascade surface flow wetland area in the form of seepage through the gaps of the wooden piles; the cascade surface flow wetland area provides an aerobic environment and mainly removes organic pollutants;

[0010] The underwater forest area is fixedly provided with a floating enclosure, the floating enclosure includes a plurality of steel pipe limiting piles, a skirt body is connected between the plurality of steel pipe limiting piles, a plurality of uniformly distributed floating bodies are connected to the top of one side of the skirt body, and a plurality of uniformly distributed counterweight stone cages are connected to the bottom of one side of the skirt body;

[0011] The first water outlet pipe is fixedly communicated with the first water inlet pipe, and the second water outlet pipe is fixedly communicated with the second water inlet pipe, sewage flows from the ecological retention area to the subsurface flow wetland through the first water outlet pipe and the first water inlet pipe, and the sewage flows from the subsurface flow wetland to the cascade surface flow wetland through the second water outlet pipe and the second water inlet pipe.

[0012] Preferably, the ecological retention area and the subsurface flow wetland are located in the same plane, the cascade surface flow wetland is located below the subsurface flow wetland, and the underwater forest area is located below the cascade surface flow wetland.

[0013] Preferably, the secondary surface flow wetland is located below the primary surface flow wetland on a side away from the second water inlet pipe, the primary surface flow wetland is located on a side close to the subsurface flow wetland, and the secondary surface flow wetland is located on a side close to the underwater forest area.

[0014] Preferably, the plant fiber layer, the first planting soil layer, the coarse sand layer and the gravel layer are all provided with the water permeable geotextile, and the water permeable geotextile is used for separating the layers.

[0015] Preferably, the impermeable membrane comprises two non-woven fabrics and an HDPE film, the HDPE film is located between the two non-woven fabrics, and the impermeable membrane is used for preventing the sewage from seeping into underground water.

[0016] Preferably, the top of the water distribution area and the top of the water collection area are provided with prefabricated cover plates in a clamping mode, so as to prevent sundries and garbage from entering the water distribution area and the water collection area.

[0017] Preferably, the floating body is a cylindrical high-molecular polypropylene floating body, the skirt body is made of a curtain cloth, the floating body provides upward tension for the top of the skirt body through buoyancy, and the skirt body is a main body of the floating type enclosure and plays a role of enclosure.

[0018] Compared with the prior art, the utility model has the advantages of making full use of the river bank slope space, not occupying construction land, low operation cost, good purification effect, simple maintenance, not affecting river flood discharge, improving bank slope stability, and being beneficial to the recovery of river aquatic organisms. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a structural schematic view of the utility model;

[0020] Figure 2 It is a structural schematic view of the ecological retention area of the utility model;

[0021] Figure 3 It is a structural schematic view of the subsurface flow wetland of the utility model;

[0022] Figure 4 It is a plan view of the subsurface flow wetland area of the utility model;

[0023] Figure 5 It is a sectional view of the subsurface flow wetland area of the utility model;

[0024] Figure 6 It is a structural schematic view of the cascade surface flow wetland area of the utility model;

[0025] Figure 7 It is a structural schematic view of the underwater forest area of the utility model.

[0026] In the drawing: 1, ecological retention area; 11, gravel layer; 12, coarse sand layer; 13, first planting soil layer; 14, plant fiber layer; 15, impermeable membrane; 16, permeable pipe; 17, permeable geotextile; 18, first water outlet pipe; 2, subsurface flow wetland area; 201, base; 202, base; 203, reinforced concrete purification tank; 204, water distribution area; 205, treatment area; 206, water collection area; 207, gravel layer; 208, pebble layer; 209, prefabricated cover plate; 210, first water inlet pipe; 211, water distribution pipe; 212, water collection pipe; 213, second water outlet pipe; 214, concrete plate; 215, bed body; 3, cascade surface flow wetland area; 31, first stage surface flow wetland; 32, second stage surface flow wetland; 33, second water inlet pipe; 34, volcanic rock layer; 35, second planting soil layer; 4, underwater forest area; 41, steel pipe limiting pile; 42, floating body; 43, skirt body; 44, counterweight stone cage. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model.

[0028] Please refer to Figures 1-7 The utility model provides a bank slope type tail water purification system, including ecological retention area 1, subsurface flow wetland area 2, cascade surface flow wetland area 3 and underwater forest area 4, ecological retention area 1, subsurface flow wetland area 2, cascade surface flow wetland area 3 and underwater forest area 4 are arranged in turn.

[0029] Please refer to Figures 1-2 Ecological retention area 1 is provided with plant fiber layer 14, first planting soil layer 13, coarse sand layer 12 and gravel layer 11 from top to bottom in turn, and the bottom of gravel layer 11 is provided with impermeable membrane 15, and permeable pipe 16 is arranged in gravel layer 11, and first water outlet pipe 18 extending out of gravel layer 11 is communicated with permeable pipe 16; the thickness of plant fiber layer 14 is 5cm, and the base surface density is 20kg / m 3 The fiber layer is planted with iris and other emergent plants, and the planting density is 3 / m 2, the first planting soil layer 13 has a thickness of 20 cm, the coarse sand layer 12 has a thickness of 10 cm, the gravel layer 11 has a thickness of 30 cm, the gravel layer 11 is provided with a water-permeable pipe 16 with a diameter of 15 cm, surface source sewage is filtered from the surface of the ecological retention area 1 to the lower layer, is collected in the water-permeable pipe 16 and is discharged, after the treatment by the process, most of the particulate pollutants in the sewage are removed, and a certain amount of nitrate nitrogen is formed under the oxidation condition.

[0030] Please refer to Figures 1-5 , the undercurrent wet area 2 comprises a base 201, a bottom 202 is fixedly arranged at the top of the base 201, a reinforced concrete purification tank 203 is fixedly arranged at the top of the bottom 202, the reinforced concrete purification tank 203 is provided with a water distribution area 204, a water collecting area 206 and a treatment area 205 between the water distribution area 204 and the water collecting area 206, a first water inlet pipe 210 in communication with the water distribution area 204 is arranged at one end of one side of the reinforced concrete purification tank 203, a second water outlet pipe 213 in communication with the water collecting area 206 is arranged at the middle of the other side of the reinforced concrete purification tank 203, two concrete plates 214 are arranged in the treatment area 205, the treatment area 205 is divided into three bed bodies 215 through the two concrete plates 214, the three bed bodies 215 are sequentially provided with a gravel layer 207 and a pebble layer 208 from top to bottom, a water distribution pipe 211 in communication with the water distribution area 204 is arranged in the pebble layer 208, a water collecting pipe 212 in communication with the water collecting area 206 is arranged in the gravel layer 207, and the first water outlet pipe 18 is fixedly communicated with the first water inlet pipe 210; the sewage first enters the water distribution area 204 through the first water inlet pipe 210, is uniformly arranged to the bottom of the three bed bodies 215 of the treatment area 205 through the water distribution pipe 211, flows from the bottom to the top, flows through the pebble layer 208 and the gravel layer 207, after a period of time, a biological membrane is formed on the surface of the pebble layer 208 and the gravel layer 207, the microbial biological membrane absorbs soluble organic pollutants in the sewage as nutrients required for its physiological activities, and the organic pollutants are decomposed in the metabolism process, the sewage enters the water collecting area 206 through the water collecting pipe 212 on the surface of the bed body 215, and enters the gradient surface flow wet area 3 through the second water outlet pipe 213.

[0031] Please refer to Figure 1 and Figure 6 , the gradient surface flow wet area 3 comprises a first-stage surface flow wetland 31 and a second-stage surface flow wetland 32, a second water inlet pipe 33 is arranged at the top of one side of the first-stage surface flow wetland 31, the first-stage surface flow wetland 31 and the second-stage surface flow wetland 32 are sequentially provided with a volcanic rock layer 34 and a second planting soil layer 35 from top to bottom, and the second water outlet pipe 213 is fixedly communicated with the second water inlet pipe 33; the gradient surface flow wet area 3 is composed of two-stage surface flow wetlands, the structures of the two-stage surface flow wetlands are consistent, and the sewage overflows from the first-stage surface flow wetland 31 into the second-stage surface flow wetland 32.

[0032] Please refer to Figure 1 and Figure 7 The floating enclosure is fixedly arranged in the underwater forest area 4, and the floating enclosure comprises a plurality of steel pipe limiting piles 41, a plurality of steel pipe limiting piles 41 are connected with a skirt body 43, the top of one side of the skirt body 43 is connected with a plurality of uniformly distributed floating bodies 42, and the bottom of one side of the skirt body 43 is connected with a plurality of uniformly distributed counterweight stone cages 44; the floating body 42 is a cylindrical high-molecular polypropylene floating body 42, the length of the semi-cylindrical body is not less than 600 mm, and the height is not less than 380 mm; the material of the skirt body 43 is screen cloth, and the unit area mass is not less than 400 g / m 2 , the radial tensile strength is greater than or equal to 100 KN / m, and the weft tensile strength is greater than or equal to 70 KN / m.

[0033] The ecological retention area 1 and the subsurface wetland area 2 are located on the same plane, the cascade surface flow wetland area 3 is located below the subsurface wetland area 2, the underwater forest area 4 is located below the cascade surface flow wetland area 3, the non-point source pollution drainage relies on gravity flow, sequentially passes through the ecological retention area 1, the subsurface wetland area 2, the cascade surface flow wetland area 3 and the underwater forest area 4, and then enters the main river channel in the form of overflow.

[0034] The secondary surface flow wetland 32 is located below the first surface flow wetland 31 away from the second water inlet pipe 33, the first surface flow wetland 31 is located on one side close to the subsurface wetland area 2, the secondary surface flow wetland 32 is located on one side close to the underwater forest area 4, the water flows in the form of wood pile gap overflow in the cascade surface flow wetland area 3, the cascade surface flow wetland area 3 provides an aerobic environment and mainly removes organic pollutants.

[0035] The water-permeable geotextile 17 is arranged between the plant fiber layer 14 and the first planting soil layer 13, between the first planting soil layer 13 and the coarse sand layer 12, and between the coarse sand layer 12 and the gravel layer 11, so as to avoid that the fillers in the layers are mixed together and thus the filtration effect is reduced.

[0036] The impermeable membrane 15 comprises two non-woven fabrics and an HDPE film, the HDPE film is located between the two non-woven fabrics, and the impermeable membrane 15 prevents the sewage from seeping into underground water.

[0037] The top of the water distribution area 204 and the top of the water collection area 206 are clamped with prefabricated cover plates 209, and the prefabricated cover plates 209 block sundries and garbage from entering the water distribution area 204 and the water collection area 206.

[0038] In use, the non-point source pollution drainage relies on gravity flow, sequentially passes through the ecological retention area 1, the subsurface wetland area 2, the cascade surface flow wetland area 3 and the underwater forest area 4, and then enters the main river channel in the form of overflow;

[0039] The specific process is as follows: the ecological retention area 1 is composed of a plant fiber layer 14, a first planting soil layer 13, a coarse sand layer 12 and a gravel layer 11, the surface source sewage is filtered from the surface of the ecological retention area 1 to the lower layer, and sequentially passes through the plant fiber layer 14, the first planting soil layer 13, the coarse sand layer 12 and the gravel layer 11, most of the particulate pollutants in the sewage are removed, and a certain amount of nitrate nitrogen is formed under the oxidation condition, the sewage is collected through the water permeable pipe 16 and discharged, enters the distribution area 204 through the first water inlet pipe 210, is uniformly arranged to the bottom of the three bed bodies 215 of the treatment area 205 through the water distribution pipe 211, flows from the lower layer to the upper layer, flows through the pebble layer 208 and the gravel layer 207, and after a period of time, the biological membrane is formed on the surface of the gravel layer 207 and the pebble layer 208, the microbial biological membrane absorbs the soluble organic pollutants in the sewage as the nutrient substances required for its physiological activities, and the organic pollutants are decomposed in the metabolism process, the sewage enters the water collecting area 206 through the water collecting pipe 212 on the surface of the bed body 215, enters the gradient surface flow wetland area 3 through the second water outlet pipe 213, the gradient surface flow wetland area 3 is composed of two gradient surface flow wetlands, the structures of the two gradient surface flow wetlands are consistent, the sewage overflows from the first gradient surface flow wetland 31 into the second gradient surface flow wetland 32, the outer periphery of the underwater forest area 4 is provided with a floating type enclosure, the floating type enclosure is composed of a floating body 42, a skirt body 43 and a counterweight stone cage 44, the floating body 42 is a cylindrical high molecular polypropylene floating body, and the skirt body 43 is made of a curtain cloth.

[0040] Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or make equivalent replacement to part of the technical features, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A bank slope type tailwater purification system comprising an ecological retention area (1), a subsurface wetland area (2), a cascade overland wetland area (3) and an underwater forest area (4), characterized in that: The ecological retention area (1), the subsurface wetland area (2), the cascade surface flow wetland area (3) and the underwater forest area (4) are arranged in sequence. The ecological retention area (1) is sequentially provided from top to bottom with a plant fiber layer (14), a first planting soil layer (13), a coarse sand layer (12) and a gravel layer (11), the bottom of the gravel layer (11) is provided with an anti-seepage film (15), the gravel layer (11) is provided with a water permeable pipe (16), and the water permeable pipe (16) is communicated with a first water outlet pipe (18) extending out of the gravel layer (11). The subsurface wetland area (2) comprises a base (201), the top of the base (201) is fixedly provided with a base (202), the top of the base (202) is fixedly provided with a reinforced concrete purification tank (203), the reinforced concrete purification tank (203) is provided with a water distribution area (204), a water collection area (206) and a treatment area (205) between the water distribution area (204) and the water collection area (206), one end of one side of the reinforced concrete purification tank (203) is provided with a first water inlet pipe (210) communicated with the water distribution area (204), the middle of the other side of the reinforced concrete purification tank (203) is provided with a second water outlet pipe (213) communicated with the water collection area (206), and the inside of the treatment area (205) is provided with two concrete plates (214). The treatment area (205) is divided into three bed bodies (215) by the two concrete plates (214), the inside of each of the three bed bodies (215) is sequentially provided from top to bottom with a gravel layer (207) and a pebble layer (208), the pebble layer (208) is paved with a water distribution pipe (211) communicated with the water distribution area (204), and the gravel layer (207) is paved with a water collection pipe (212) communicated with the water collection area (206). The cascade surface flow wetland area (3) comprises a first-stage surface flow wetland (31) and a second-stage surface flow wetland (32), the top of one side of the first-stage surface flow wetland (31) is provided with a second water inlet pipe (33), and the first-stage surface flow wetland (31) and the second-stage surface flow wetland (32) are sequentially provided from top to bottom with a volcanic rock layer (34) and a second planting soil layer (35). The underwater forest area (4) is fixedly provided with a floating type enclosure, the floating type enclosure comprises a plurality of steel pipe limiting piles (41), the plurality of steel pipe limiting piles (41) are connected with a skirt body (43), the top of one side of the skirt body (43) is connected with a plurality of uniformly distributed floating bodies (42), and the bottom of one side of the skirt body (43) is connected with a plurality of uniformly distributed counterweight stone cages (44). The first water outlet pipe (18) and the first water inlet pipe (210) are fixedly communicated, and the second water outlet pipe (213) and the second water inlet pipe (33) are fixedly communicated.

2. A bank slope type tail water purification system according to claim 1, characterized in that: The ecological retention area (1) and the subsurface wetland area (2) are located on the same plane, the cascade surface flow wetland area (3) is located below the subsurface wetland area (2), and the underwater forest area (4) is located below the cascade surface flow wetland area (3).

3. A bank slope type tail water purification system according to claim 1, characterized in that: The secondary surface flow wetland (32) is located below the primary surface flow wetland (31) on the side away from the second water inlet pipe (33), the primary surface flow wetland (31) is located on the side close to the subsurface flow wetland area (2), and the secondary surface flow wetland (32) is located on the side close to the underwater forest area (4).

4. A bank slope type tail water purification system according to claim 1, characterized in that: The water-permeable geotextile (17) is arranged between the plant fiber layer (14) and the first planting soil layer (13), between the first planting soil layer (13) and the coarse sand layer (12), and between the coarse sand layer (12) and the gravel layer (11).

5. A bank slope type tail water purification system according to claim 1, characterized in that: The anti-seepage membrane (15) comprises two non-woven fabrics and an HDPE film, and the HDPE film is located between the two non-woven fabrics.

6. A bank slope type tail water purification system according to claim 1, characterized in that: The top of the water distribution area (204) and the top of the water collection area (206) are clamped with prefabricated cover plates (209).

7. A bank slope type tail water purification system according to claim 1, characterized in that: The floating body (42) is a cylindrical polypropylene floating body (42), and the skirt body (43) is made of a canvas.

Images