Urban rainwater ecological treatment system

Abstract

The utility model discloses an urban rainwater ecological treatment system. The urban rainwater ecological treatment system comprises a rough filtration area arranged on one side far away from a river; vegetation is planted in the primary filtering treatment area; the surface drainage area comprises a gabion net and filtering fragments filled in the gabion net; rainwater passes through the rough filtration area, the primary filtration treatment area and the surface drainage area to form a first filtration path for draining urban rainwater into a river; the retaining wall is located between the river and the surface drainage area; the underground purification area is positioned at the bottoms of the primary filtration treatment area and the surface drainage area; the rainwater passes through the rough filtration area, the primary filtration treatment area and the underground purification area to form a second filtration path for discharging urban rainwater into an underground water source; the underground drainage unit is arranged in the underground purification area, and one end of the underground drainage unit penetrates through the retaining wall to be communicated with air above the river; rainwater passes through the rough filtration area, the primary filtration treatment area, the underground purification area and the underground drainage unit to form a third filtration path for discharging urban rainwater into a river. The urban rainwater ecological treatment system can be used for effectively purifying different rainfall amounts.

Description

Technical Field

[0001] The utility model relates to the technical field of urban sewage treatment, in particular to an urban rainwater ecological treatment system. Background Art

[0002] Water resources are an important part of the development process of many cities. In order to alleviate the problem of water shortage in cities, it is necessary to increase revenue and reduce expenditure and develop as much available water resources as possible.

[0003] In today's cities, due to the influence of factories or car exhaust, if there is heavy rain, the rainwater dissolves the acidic gases in the air and falls to the ground. In addition, some trees are usually planted by the river. When it rains, the rainwater usually washes together impurities such as fallen leaves and dust on the road to form mixed pollutants, which then flow into the rivers on both sides of the road, causing serious pollution to the water body. The current common treatment method is usually to plant a variety of trees, shrubs or aquatic plants on the river bank, and use the roots of the plants for a preliminary purification before discharging them into the river.

[0004] For example, the publication number is CN103306360A, and the name is "Multi-dimensional ecological drainage system for intercepting and controlling pollutants entering the river by diversion system of rainwater". The system is set on one side of the river bank and is stepped along the river bank; the rainwater from the pipe network flows into the first-level drop platform through the rainwater pipe, enters the regulating pool, and then flows into the ecological buffer zone through the second-level drop platform, and then flows into the vegetation retention pool through the third-level drop platform; the first-level drop platform and the ecological buffer zone are sloped, and the vegetation retention pool is planted with plants, which reduces the risk of rainwater pollution runoff directly entering the river while ensuring drainage, reduces the impact and damage to the water quality of the river water body, realizes the effective control of pollutants entering the river and the improvement of the water environment, and also enhances the landscape value of the urban water body. However, since the patent only sets three levels of continuous vegetation on the ground, it can only play a simple purification, filtration and regulation role, and the rainwater treatment means are relatively single, and it is impossible to fully filter and purify the rainwater, and it is impossible to form a perfect rainwater treatment system to cope with different rainfall. Utility Model Content

[0005] The technical problem to be solved by the utility model is to provide an urban rainwater ecological treatment system in view of the deficiencies of the above-mentioned prior art, and the urban rainwater ecological treatment system can effectively purify and treat different rainfall amounts.

[0006] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0007] An urban rainwater ecological treatment system includes a coarse filtration area, a primary filtration treatment area, a surface drainage area, a retaining wall, an underground purification area and an underground drainage unit; the coarse filtration area is arranged on a side away from the river; the primary filtration treatment area is arranged on the right side of the coarse filtration area and is lower in height than the coarse filtration area, and vegetation is planted in the primary filtration treatment area; the surface drainage area is arranged on the right side of the primary filtration treatment area and is lower in height than the primary filtration treatment area, and the surface drainage area includes a gabion mesh and filtering fragments filled in the gabion mesh; rainwater passes through the coarse filtration area, the primary filtration treatment area and the surface drainage area to form a first filtration path for urban rainwater to be discharged into the river; the retaining wall is vertically arranged at The right side of the surface drainage area and its lower side extends to the underground purification area, it is located between the river and the surface drainage area, and the top of the retaining wall is higher than the surface drainage area; the underground purification area is located at the bottom of the primary filtration treatment area and the surface drainage area; the rainwater passes through the coarse filtration area, the primary filtration treatment area, and the underground purification area to form a second filtration path for urban rainwater to be discharged into the groundwater source; the underground drainage unit is arranged in the underground purification area, and one end of the underground drainage unit passes through the retaining wall and is connected to the air above the river; the rainwater passes through the coarse filtration area, the primary filtration treatment area, the underground purification area, and the underground drainage unit to form a third filtration path for urban rainwater to be discharged into the river.

[0008] Preferably, the coarse filtration area includes a groove and a cover plate; the groove is concave, and the side of the groove close to the river is lower than the side away from the river; the cover plate is horizontally arranged and connected to the side of the mouth of the groove close to the river, and there is a gap on the side of the groove away from the river.

[0009] Preferably, the surface of the primary filtration treatment area is in a stepped wave shape, with the height gradually decreasing from left to right.

[0010] Preferably, a water-filtering geotextile is provided between the primary filtration treatment area, the surface drainage area and the underground purification area.

[0011] Preferably, the underground purification area includes a quartz sand layer, a gravel layer and a slag layer, which are arranged in sequence from top to bottom; a water-filtering geotextile is provided between the quartz sand layer and the gravel layer; and the underground drainage unit is located in the quartz sand layer.

[0012] Preferably, the underground drainage unit includes a drainage pipe and a filter mesh layer; the drainage pipe is located in the underground purification area, one end of which is closed and the other end is connected to the air above the river, and the drainage pipe is provided with water-permeable holes; the filter mesh layer is coated on the outer circumference of the drainage pipe.

[0013] Preferably, the water permeable hole is located in the lower half of the drain pipe.

[0014] Preferably, the drainage pipe is arranged horizontally along the ground.

[0015] Preferably, the drainage pipe is arranged at an inclination, with the end thereof close to the river being lower than the end thereof located in the underground purification area.

[0016] Preferably, the primary filtration treatment area, the surface drainage area and the underground purification area are arranged with an overall downward slope from left to right.

[0017] The utility model has the following beneficial effects:

[0018] By reasonably arranging the coarse filtration area, primary filtration treatment area and underground purification area, and combining the surface drainage area and the underground drainage unit to form three water filtration paths in the horizontal and vertical directions, filtration and purification of different water flow rates can be achieved. When the rainfall is small, the rainwater flows through the second filtration path, and is discharged into the groundwater after being filtered through the coarse filtration area, the primary filtration treatment area and the underground purification area. When the rainfall is slightly larger, the rainwater flows through the third filtration path, and finally flows into the river through the underground drainage unit in the underground purification area. When the rainfall is larger, the rainwater passes through the first filtration path, directly passes through the coarse filtration area and the primary filtration treatment area, and then passes through the surface drainage area to be discharged into the river, so that it can cope well with different rainfall amounts, and the rainwater is sent to the river or groundwater source after being filtered and purified. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The utility model is a structural schematic diagram of an urban rainwater ecological treatment system.

[0020] These include: 1. coarse filter area; 101. groove; 102. cover plate; 103. gap;

[0021] 2. Primary filtration treatment area;

[0022] 3. Surface drainage area; 301. Gabion mesh; 302. Filter debris;

[0023] 4. Retaining wall;

[0024] 5. Underground purification area; 501. Quartz sand layer; 502. Gravel layer; 503. Slag layer;

[0025] 6. Underground drainage unit; 601. Drain pipe; 602. Filter layer; 603. Water permeable hole;

[0026] 7. River; 8. Geotextile. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific preferred embodiments.

[0028] like Figure 1 As shown, an urban rainwater ecological treatment system includes a coarse filtration area 1, a primary filtration treatment area 2, a surface drainage area 3, a retaining wall 4, an underground purification area 5 and an underground drainage unit 6.

[0029] The coarse filtration area 1 is arranged on the side away from the river 7 for filtering solid impurities; the coarse filtration area 1 includes a groove 101 and a cover plate 102; the groove 101 is recessed, and the side of the groove 101 close to the river 7 is lower than the side away from the river 7; the cover plate 102 is horizontally arranged and movably connected to the side of the mouth of the groove 101 close to the river 7, and the groove 101 has a gap 103 on the side away from the river 7.

[0030] Specifically, the groove 101 is usually arranged on the side of the road to form the first filtering defense line. The cover plate 102 covers the mouth of the groove 101. The side of the cover plate 102 close to the river 7 is connected to the side of the mouth of the groove 101. A gap 103 is formed between the side of the cover plate 102 away from the river 7 and the groove 101, which is convenient for coarse filtering of rainwater flowing through the coarse filtration area 1 after being washed from the road. Fallen leaves, mud or solid garbage in the rainwater flows into the groove 101, is blocked by the cover plate 102, and remains in the groove 101. When there are too many impurities in the groove 101, the cover plate 102 can be lifted to clean the debris inside the groove 101; at the same time, the coarse filtration area 1 can effectively reduce the initial kinetic energy of the water flow upstream of the subsequent primary filtration treatment area 2, and slow down the loss of soil in the primary filtration treatment area 2 caused by water scouring. Preferably, the bottom of the side of the cover plate 102 away from the river 7 is suspended by a crossbeam, and a plurality of vertical beams supported in the groove 101 are arranged at intervals at the bottom of the crossbeam for support. Preferably, a layer of wire mesh can be arranged at the bottom of the cover plate 102, and the pores of the wire mesh are small, which can block impurities such as fallen leaves in the groove 101, and prevent these impurities from flowing into the downstream primary filtration treatment area 2 through the pores of the cover plate 102. The side of the groove 101 close to the river 7 is lower than the side away from the river 7, so that rainwater can flow toward the river 7 after overflowing the cover plate 102, enter the primary filtration treatment area 2, and avoid reverse flow to the road.

[0031] The primary filtration treatment area 2 is arranged on the right side of the coarse filtration area 1 and is lower in height than the coarse filtration area 1. Vegetation is planted in the primary filtration treatment area 2 to form a biofilm for primary filtration. The primary filtration treatment area 2 is based on a denitrification process and uses a biofilm to filter rainwater. The planted vegetation will form a biofilm in the surface water after being washed by rainwater, and then the rainwater is preliminarily filtered by biological purification. Preferably, in order to increase the residence time of rainwater passing through the primary filtration treatment area 2, the vegetation is a plurality of planting belts, and the surface of the planting belts is set inward, so that the rainwater stagnates when it reaches the primary filtration treatment area 2 and infiltrates into the underground purification area 5. The inward setting increases the capacity of the rainwater treatment system and effectively reduces the risk of urban waterlogging; the surface of the primary filtration treatment area 2 is in a stepped wavy shape, and the height gradually decreases from left to right. While increasing the rainwater treatment capacity, it is convenient for rainwater to flow to a lower place. At the same time, the wave-like setting can fully accommodate more rainwater to infiltrate downward for treatment.

[0032] Among them, the vegetation planted in the planting belt should be selected from perennial emergent water-loving and wetland herbaceous plants with the characteristics of well-developed root system, strong pollution resistance, strong disease and insect resistance, etc. After completion, artificial proportioning should be carried out according to the pollutants of road rainwater monitored manually in the local area, and artificial simulated rainwater should be used for saturated irrigation of the primary filtration treatment area 2 to quickly form a biofilm, which is conducive to the biological purification of polluted water after natural rainfall in the future, and quickly remove organic matter, nitrogen, phosphorus and other pollutants in the water.

[0033] The surface drainage area 3 is arranged on the right side of the primary filtration treatment area 2 and is lower in height than the primary filtration treatment area 2, and is used for emergency filtration of water discharged into the river 7. The surface drainage area 3 includes a gabion mesh 301 and filter fragments 302 filled in the gabion mesh 301. Specifically, the width of the gabion mesh 301 is 0.8 meters to 1.2 meters, and the width direction is perpendicular to the water flow direction on the horizontal plane. The bottom is arranged at the junction of the primary filtration treatment area 2 and the underground purification area 5, and the top extends upward to the surface and is covered with green vegetation. The gabion mesh 301 can be made of hot-dip galvanized steel wire, and the internal filling of crushed stone serves as a filter medium. A water-filtering geotextile 8 is arranged on the side of the gabion mesh 301 close to the primary filtration treatment area 2 to prevent the soil in the primary filtration treatment area 2 from infiltrating into the gabion mesh 301.

[0034] The retaining wall 4 is vertically arranged on the right side of the surface drainage area 3 , and its lower edge extends to the underground purification area 5 , and is located between the river 7 and the surface drainage area 3 . The top of the retaining wall 4 is higher than the surface drainage area 3 .

[0035] The underground purification area 5 is located at the bottom of the primary filtration treatment area 2 and the surface drainage area 3; the underground purification area 5 includes a quartz sand layer 501, a gravel layer 502 and a slag layer 503, which are arranged from top to bottom; a water-filtering geotextile 8 is arranged between the quartz sand layer 501 and the gravel layer 502; and the underground drainage unit 6 is located in the quartz sand layer 501. Rainwater enters the underground purification area 5 from the primary filtration treatment area 2 above under the action of gravity after biological purification. After being filtered and purified by each soil layer, most of the impurities and nitrogen oxides in the rainwater have been removed and can be used to supplement urban groundwater resources.

[0036] A water-filtering geotextile 8 for isolation is provided between the primary filtration treatment area 2 , the surface drainage area 3 and the underground purification area 5 . The water-filtering geotextile 8 serves to isolate the various areas and avoid mixing of the filter media between the areas. At the same time, water can penetrate through the water-filtering geotextile 8 .

[0037] The underground drainage unit 6 is arranged in the underground purification area 5, and one end of the underground drainage unit 6 penetrates the retaining wall 4 and communicates with the air above the river 7; the underground drainage unit 6 includes a drainage pipe 601 and a filter mesh layer 602; the drainage pipe 601 is arranged at the junction of the quartz sand layer 501 and the gravel layer 502 and is located above the water-filtering geotextile 8, one end of the drainage pipe 601 located in the underground purification area 5 is closed, and the other end is connected to the air above the river 7, and the drainage pipe 601 is arranged horizontally or obliquely along the ground direction, and when it is inclined, the end close to the river 7 is lower than the end located in the underground purification area 5. A plurality of water-permeable holes 603 are opened on the side wall of the drainage pipe 601, and the water-permeable holes 603 are preferably located in the lower half of the drainage pipe. The drainage pipe 601 can be implemented by PPR pipes, etc. The water-permeable hole 603 is located in the lower half of the drainage pipe 601. When the rainwater runoff is too large and there is no time to penetrate into the groundwater, the rainwater can be directly discharged into the river 7 through the water-permeable hole 603 on the drainage pipe 601 to avoid waterlogging in the upper primary filtration treatment area 2. The filter mesh layer 602 is coated on the outer periphery of the drainage pipe 601 to prevent the medium in the underground purification area 5 from entering the water-permeable hole 603, that is, to prevent the particles in the quartz sand layer 501 from being discharged into the river 7 through the water-permeable hole 603, causing ground collapse. The filter mesh layer 602 can be made of wire mesh, etc. When the underground drainage unit 6 is blocked, the water pipe can be connected to the end of the drainage pipe 601 that is connected to the air, and repeated flushing with water can restore the smoothness.

[0038] The primary filtration treatment area 2, the surface drainage area 3 and the underground purification area 5 are arranged with a downward slope from left to right as a whole, so that the water flow tends to flow toward the river. The underground drainage unit 6 is also arranged with an inclination along the inclination trend of the underground purification area 5. In this way, the end of the underground drainage unit 6 close to the river 7 is formed as a low end, which facilitates the water entering the underground drainage unit 6 to flow into the river 7.

[0039] The rainwater passes through the coarse filtration area 1, the primary filtration treatment area 2, and the surface drainage area 3 to form the first filtration path for urban rainwater to be discharged into the river 7; the rainwater passes through the coarse filtration area 1, the primary filtration treatment area 2, and the underground purification area 5 to form the second filtration path for urban rainwater to be discharged into the groundwater source; the rainwater passes through the coarse filtration area 1, the primary filtration treatment area 2, the underground purification area 5, and the underground drainage unit 6 to form the third filtration path for urban rainwater to be discharged into the river 7. By reasonably arranging the coarse filtration area 1, the primary filtration treatment area 2, and the underground purification area 5, and combining the surface drainage area 3 and the underground drainage unit 6 to form three water filtration paths, filtration and purification corresponding to different water flow rates can be achieved.

[0040] The rainwater flow is roughly divided into three levels from small to large. When the rainwater is small, it flows through the second filtration path. Specifically, the rainwater passes through the coarse filtration area 1 to preliminarily filter impurities such as fallen leaves, and then passes through the primary filtration treatment area 2, using the biofilm formed by plants and rainwater, and then uses biological purification to remove organic matter, nitrogen, phosphorus and other pollutants in the rainwater, and then penetrates downward into the underground purification area 5 for re-filtration, and then enters the groundwater source.

[0041] When the rainwater is a little heavy, it can flow through the third filter path while flowing through the second filter path. Specifically, when the rainwater entering the underground purification area 5 for treatment does not have time to penetrate downward, the rainwater reversely permeates upward, and then is discharged into the river 7 through the underground drainage unit 6 located in the underground purification area 5, which can prevent rainwater from accumulating in the underground purification area 5 and the primary filtration treatment area 2 to cause waterlogging.

[0042] When the rainwater is at its maximum, it can flow through the first filter path while flowing through the second filter path and the third filter path. Specifically, after the rainwater passes through the coarse filtration area 1 and the primary filtration treatment area 2, it does not have time to penetrate downward into the underground purification area 5, and directly flows into the surface drainage area 3, and then overflows from the retaining wall 4 into the river 7 after being filtered.

[0043] The boundaries between the three rainfall levels are fuzzy, and rainwater automatically flows according to the rainfall distribution path, and does not strictly follow the one-to-one correspondence to form three filtering paths for flow. It can cope well with different rainfall levels, and after filtering and purifying the rainwater, it is sent to the river7 or groundwater source.

[0044] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical scheme of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. An urban rainwater ecological treatment system, characterized in that: It includes a coarse filtration area (1), a primary filtration treatment area (2), a surface drainage area (3), a retaining wall (4), an underground purification area (5) and an underground drainage unit (6); The coarse filtration area (1) is arranged on the side away from the river (7); The primary filtration treatment area (2) is arranged on the right side of the coarse filtration area (1) and is lower in height than the coarse filtration area (1), and vegetation is planted in the primary filtration treatment area (2); The surface drainage area (3) is arranged on the right side of the primary filtration treatment area (2) and is lower in height than the primary filtration treatment area (2). The surface drainage area (3) includes a gabion mesh (301) and filter fragments (302) filled in the gabion mesh (301). The rainwater passes through the coarse filtration area (1), the primary filtration treatment area (2), and the surface drainage area (3) to form a first filtration path for urban rainwater to be discharged into the river (7); The retaining wall (4) is vertically arranged on the right side of the surface drainage area (3), and its lower edge extends to the underground purification area (5), and is located between the river (7) and the surface drainage area (3). The top of the retaining wall (4) is higher than the surface drainage area (3); The underground purification area (5) is located at the bottom of the primary filtration treatment area (2) and the surface drainage area (3); The rainwater passes through the coarse filtration area (1), the primary filtration treatment area (2), and the underground purification area (5) to form a second filtration path for urban rainwater to be discharged into the underground water source; An underground drainage unit (6) is arranged in the underground purification area (5), and one end of the underground drainage unit (6) penetrates the retaining wall (4) and is connected to the air above the river (7); The rainwater passes through the coarse filtration area (1), the primary filtration treatment area (2), the underground purification area (5), and the underground drainage unit (6) to form a third filtration path for urban rainwater to be discharged into the river (7).

2. The urban rainwater ecological treatment system according to claim 1 is characterized by: The coarse filtration area (1) comprises a groove (101) and a cover plate (102); The groove (101) is arranged to be concave, and a side of the groove (101) close to the river (7) is lower than a side of the groove (101) away from the river (7); The cover plate (102) is arranged horizontally and connected to the side edge of the mouth of the groove (101) close to the river (7), and a gap (103) is provided on the side of the groove (101) away from the river (7).

3. The urban rainwater ecological treatment system according to claim 1 is characterized by: The surface of the primary filtration treatment area (2) is in a stepped wave shape, with the height gradually decreasing from left to right.

4. The urban rainwater ecological treatment system according to claim 1 is characterized by: A water filtering geotextile (8) is provided between the primary filtration treatment area (2), the surface drainage area (3) and the underground purification area (5).

5. The urban rainwater ecological treatment system according to claim 1 is characterized by: The underground purification area (5) comprises a quartz sand layer (501), a gravel layer (502) and a slag layer (503), wherein the quartz sand layer (501), the gravel layer (502) and the slag layer (503) are arranged in sequence from top to bottom; a water filter geotextile (8) is arranged between the quartz sand layer (501) and the gravel layer (502); and the underground drainage unit (6) is located in the quartz sand layer (501).

6. The urban rainwater ecological treatment system according to claim 1 is characterized by: The underground drainage unit (6) comprises a drainage pipe (601) and a filter screen layer (602); The drainage pipe (601) is located in the underground purification area (5), one end of which is closed, and the other end of which is connected to the air above the river (7). The drainage pipe (601) is provided with a water permeable hole (603); The filter mesh layer (602) is coated on the outer circumference of the drainage pipe (601).

7. The urban rainwater ecological treatment system according to claim 6 is characterized by: The water permeable hole (603) is located at the lower half of the drainage pipe (601).

8. The urban rainwater ecological treatment system according to claim 6 is characterized by: The drainage pipe (601) is arranged horizontally along the ground.

9. The urban rainwater ecological treatment system according to claim 6, characterized in that: The drainage pipe (601) is arranged at an inclination, with the end thereof close to the river (7) being lower than the end thereof located in the underground purification area (5).

10. The urban rainwater ecological treatment system according to claim 1, characterized in that: The primary filtration treatment area (2), the surface drainage area (3) and the underground purification area (5) are arranged with an overall downward slope from left to right.

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