A purification device for realizing diversion treatment of runoff rainwater pollution
By setting up level control wells and overflow wells in rain gardens, rainwater is diverted and treated. Combined with plant and microbial systems to purify rainwater, the problem of high pollutant concentration in rain garden drainage is solved, and the reuse and purification of rainwater are achieved.
Patent Information
- Application Number
- CN202521225729.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-16
- Publication Date
- 2026-06-26
- Estimated Expiration
- 2035-06-16
AI Technical Summary
Existing rain gardens discharge rainwater with high concentrations of pollutants, posing a risk of water pollution, and rainwater resources are not being used effectively.
The rain garden is equipped with a level control well and an overflow well to achieve rainwater diversion and treatment. Initial rainwater is stored in the garden, while rainwater in the middle and later stages is discharged through the overflow well and purified by plants, composite fillers and microbial systems. The purified rainwater is then used for water replenishment and green space irrigation.
It reduces the concentration of pollutants in rainwater discharge, alleviates water pollution, enables rainwater reuse, improves purification efficiency, and avoids damage to the rain garden system.
Smart Images
Figure CN224411551U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of water environment management technology, specifically relating to a purification device for diverting and treating runoff rainwater pollution. Background Technology
[0002] With the rapid advancement of urbanization, the increase in a large number of impermeable surfaces (such as asphalt roads, concrete roads, buildings, etc.) has changed the original underlying surface conditions, resulting in a shortened runoff time and an increase in rainwater runoff. However, rainwater runoff contains a large amount of nitrogen, phosphorus, and organic pollutants, which has gradually become one of the main causes of eutrophication in rivers, lakes, and other water systems, and the resulting water pollution problems have attracted much attention. At the same time, urban water demand is also increasing year by year, and the contradiction between urban water demand and scarce water resources is becoming increasingly intense.
[0003] "Sponge city construction" is a new model strongly advocated by the state in urban development and construction in recent years. It utilizes various technologies such as infiltration, retention, storage, purification, utilization, and drainage to improve the infiltration, regulation, purification, utilization, and discharge capacity of runoff rainwater, effectively alleviating water pollution and water shortage problems. Rain gardens, due to their highly efficient natural rainwater purification and treatment characteristics, have become one of the low-impact development technologies that have received much attention in the process of sponge city construction.
[0004] During rainfall, rainwater collects on the surface of the rain garden and undergoes a series of purification processes before being discharged into the municipal stormwater drainage system via storm drains. However, the discharged rainwater contains high concentrations of organic pollutants, nitrogen, and phosphorus, posing a risk of water pollution. Utility Model Content
[0005] To overcome the shortcomings of existing technologies, this utility model provides a purification device for diverting and treating runoff rainwater pollution. The device stores the initial rainwater inside a rain garden, and the rainwater in the middle and later stages of rainfall flows out through an overflow well, thereby reducing the concentration of pollutants in the discharged rainwater and alleviating water pollution.
[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0007] A purification device for diverting and treating runoff rainwater pollution, specifically comprising:
[0008] The rain garden includes a structure consisting of plants J1, planting soil J2, composite filler J3, and pebbles J4 arranged from top to bottom. A permeable geotextile K1 is installed between the planting soil J2 and the composite filler J3, and between the composite filler J3 and the pebbles J4. An impermeable membrane K2 is installed at the bottom of the pebbles J4.
[0009] The rain garden is equipped with a liquid level control well B, and the liquid level control well B is equipped with an overflow well A.
[0010] The cobblestone J4 is provided with a perforated pipe F1, which is connected to the liquid level control well B. The bottom of the liquid level control well B is connected to the recycled water tank C through the liquid level control well outlet pipe F3.
[0011] The bottom of the overflow well A is connected to the rainwater inspection well via the overflow well outlet pipe F2.
[0012] Furthermore, a duckbill valve G1 is installed on the overflow well outlet pipe F2.
[0013] Furthermore, an ultrasonic level gauge E is installed at the bottom of the top plate of the well chamber of the level control well B.
[0014] Furthermore, a reclaimed water booster pump D is installed at the bottom of the reclaimed water tank C.
[0015] Furthermore, the recycled water booster pump D is connected to the recycled water pipe F4.
[0016] Furthermore, the recycled water pipe F4 is connected to the rain garden water replenishment system and the surrounding green space irrigation system.
[0017] Furthermore, the reclaimed water booster pump D is fixed to the top plate of the reclaimed water tank via guide rail H.
[0018] Furthermore, the recycled water pipe F4 is fixed to the side wall of the recycled water tank C by pipe clamp I.
[0019] The beneficial effects of this utility model are:
[0020] 1) This utility model achieves rainwater diversion and treatment by setting up a liquid level control well and an overflow well inside the rain garden. The most polluted initial rainwater is stored inside the rain garden, while the less polluted middle and later rainwater is discharged through the overflow well. This reduces the concentration of pollutants in the discharged rainwater and alleviates water pollution.
[0021] 2) The closing of the electric valve on the bottom outlet pipe of this utility model extends the residence time of the initial rainwater inside the rain garden. At the same time, as the dissolved oxygen in the water is consumed, an effective aerobic zone, anoxic zone, and anaerobic zone are gradually formed inside the rain garden, providing a good living environment for different functional microbial communities. The purification system of plants + composite filler + microorganisms inside the rain garden system plays a physical, chemical, and biological role in further purifying and removing pollutants contained in the initial rainwater, thereby improving the purification efficiency.
[0022] 3) This utility model sets up a water recycling tank to collect rainwater after it has been treated by the rain garden, and then uses it as a water source for replenishing the rain garden and watering the surrounding green areas during the rain intervals, ensuring the continuous use of the rain garden, and realizing the recycling of water resources, thus contributing to alleviating the contradiction between urban construction and water scarcity.
[0023] 4) This utility model installs a duckbill valve on the traditional overflow well outlet pipe to prevent rainwater backflow during heavy rainfall, which could damage the rain garden system. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the purification device for treating runoff rainwater pollution according to this utility model;
[0025] In the picture:
[0026] A—Traditional overflow well, B—Level control well, C—Reclaimed water tank, D—Reclaimed water lift pump, E—Ultrasonic level gauge, F1—Perforated pipe, F2—Traditional overflow well outlet pipe, F3—Level control well outlet pipe, F4—Reclaimed water pipe, G1—Duckbill valve, G2—Electric valve, H—Guide rail, I—Pipe clamp, J1—Plant, J2—Planting soil, J3—Composite filler, J4—Pebbles, K1—Permeable geotextile, K2—Imperile membrane, H0—Storage height, h0—Depth of pebble bottom from the bottom of level control well, h1—Planting soil thickness, h2—Composite filler thickness, h3—Pebble thickness, h4—Surface flooding depth. Detailed Implementation
[0027] The present invention will now be described in detail with reference to specific embodiments.
[0028] This invention achieves rainwater diversion and treatment by setting up a level control well and an overflow well inside the rain garden. The most polluted initial rainwater is stored inside the rain garden, while the less polluted middle and later rainwater is discharged through the overflow well. This reduces the concentration of pollutants in the discharged rainwater and alleviates water pollution.
[0029] This utility model provides a purification device for diverting and treating runoff rainwater pollution, such as... Figure 1 As shown, the rain garden consists of a plant J1, planting soil J2, composite filler J3, and pebbles J4 arranged from top to bottom. A permeable geotextile K1 is installed between the planting soil J2 and the composite filler J3, and between the composite filler J3 and the pebbles J4. An impermeable membrane K2 is installed at the bottom of the pebbles J4.
[0030] A level control well B is installed inside the rain garden, and an overflow well A is installed inside the level control well B. An ultrasonic level gauge E is installed at the bottom of the top plate of the level control well B.
[0031] A perforated pipe F1 is installed inside the cobblestone J4. The perforated pipe F1 is connected to the inside of the liquid level control well B. The bottom of the liquid level control well B is connected to the recycled water tank C through the liquid level control well outlet pipe F3.
[0032] The bottom of overflow well A is connected to the rainwater inspection well through overflow well outlet pipe F2. A duckbill valve G1 is installed on overflow well outlet pipe F2 to prevent rainwater backflow caused by heavy rainfall, which could damage the rain garden system.
[0033] In this embodiment, plant J1 is a combination of sweet flag, umbrella sedge, and thaliana; the permeable geotextile specification is 200g / m². 2 The perforated pipe F1 is made of PVC with a diameter of DN150 and an opening rate of 3%. The outer wall of the perforated pipe is wrapped with permeable geotextile. The geomembrane K2 has a structure of two layers of fabric and one layer of membrane, and is in the form of HDPE geomembrane.
[0034] A reclaimed water lift pump D is installed at the bottom of the reclaimed water tank C. The reclaimed water lift pump D is connected to the reclaimed water pipe F4. The reclaimed water pipe F4 is connected to the rain garden water replenishment system and the surrounding green space irrigation system. The reclaimed water lift pump D is fixed to the top plate of the reclaimed water tank via the guide rail H. The reclaimed water pipe F4 is fixed to the side wall of the reclaimed water tank C via the pipe clamp I.
[0035] The calculation method for the water storage height H0 of a rain garden is as follows:
[0036] The first algorithm calculates the storage height based on the annual runoff volume control rate requirements for sponge city construction. H 01 The second algorithm calculates the storage height based on the volume of initial rainwater runoff. H 02 By comparing the two algorithms, the larger value calculated by the two algorithms is taken. The height unit is mm, as follows:
[0037] 1) Storage Height H 01 for:
[0038]
[0039] Where: H—design rainfall, mm;
[0040] —Combined rainfall-runoff coefficient;
[0041] F—Catchment area, hm² 2 ;
[0042] m—Porosity of the composite filler;
[0043] A—Area of the rain garden itself, hm 2 ;
[0044] 2) Storage Height H 02 for:
[0045]
[0046] Where: q—design rainfall intensity (L / (hm)) 2 / s));
[0047] t—Initial rainwater runoff time, min;
[0048] —Combined rainfall-runoff coefficient;
[0049] F—Catchment area, hm² 2 ;
[0050] m—Porosity of the composite filler;
[0051] A—Area of the rain garden itself, hm 2 .
[0052] In this embodiment, taking a rain garden located in Kunming, Yunnan Province as an example, the ratio of the area of the bioretention facility to the catchment area should be 5%-10%, and 8% is used in this case, F=A / 8%. Kunming belongs to Zone II of the annual runoff volume control rate, which is 80%~85%. The upper limit is used as the basis for calculation, and the annual runoff volume control rate is set at 85%, with a corresponding design rainfall of H=26.8mm. The porosity m of the composite filler is taken as 0.4; the comprehensive rainfall-runoff coefficient Φ is taken as 0.55. From this, the following can be calculated: H 01 It is 461mm.
[0053] Referring to the "Environmental Protection Design Standard for Chemical Construction Projects," it is advisable to take the rainwater runoff within 15 to 30 minutes of the initial rainfall as the initial rainwater runoff. In this case, the initial rainwater runoff time t is taken as 25 minutes; the comprehensive runoff coefficient is taken as 0.55.
[0054] The formula for rainstorm intensity is:
[0055]
[0056] In the formula: P is the return period, taken as P=3 years;
[0057] t—Rainfall duration (min). In this case, considering the initial runoff time, t=25min is taken.
[0058] Therefore, the calculation can be performed. H 02 The height is 491mm, and the calculated storage height H0 is: H0 = max( H 01 , H 02 =491mm.
[0059] The level control well B and the overflow well A have the same height H, including the depth h0 from the bottom of the pebble to the bottom of the level control well, the thickness h1 of the planting soil, the thickness h2 of the composite filler, the thickness h3 of the pebble, and the surface flooding depth h4. The height units are all mm. The sum of the surface flooding depth h4 and the thickness h3 of the pebble is used to overcome the head loss required for the initial runoff rainwater to flow in the rain garden. At the same time, the rainwater volume corresponding to the height h4 can also serve as a supplementary storage volume for the rain garden.
[0060] In this embodiment, the thickness h1 of the planting soil is 250mm. The thickness h2 of the composite filler is determined based on the calculated storage height H0, where h2 = 600mm > 491mm = H0. The composite filler consists of aluminum sludge and zeolite in a 4:1 ratio. The thickness h3 of the pebbles is 300mm, with a particle size between 16-32mm. The depth h0 of the bottom of the pebbles from the bottom of the liquid level control well needs to be determined based on the actual conditions, including the rainwater runoff within the rain garden's catchment area and the slope of the pipeline.
[0061] The purification method of the purification device for diverting and treating runoff rainwater pollution using this utility model is as follows:
[0062] As rainfall occurs, the initial rainwater flows around the rain garden, passes through plants J1, planting soil J2, composite filler J3, and pebbles J4 from top to bottom, and is then collected by perforated pipe F1 and flows into level control well B.
[0063] As rainfall continues, the water level in the level control well B rises continuously. The ultrasonic level gauge E installed in the level control well B detects the rise in the water level. The ultrasonic level gauge E sends a closing command to the electric valve G2, and the rain garden begins to store the initial rainwater. When the water level in the level control well B stops rising, the ultrasonic level gauge E sends a command to the electric valve G2, causing the electric valve G2 to open after a set number of days.
[0064] When the water depth in the rain garden exceeds the surface flooding depth h4, an overflow occurs. Rainwater in the middle and later stages of rainfall flows into overflow well A, and then flows through overflow well outlet pipe F2 into the nearest rainwater inspection well; the initial rainwater is intercepted in the rain garden for purification treatment, realizing the diversion treatment function.
[0065] As time goes on, the dissolved oxygen stored in the lower and middle layers of the initial rainwater in the rain garden is gradually consumed, forming effective aerobic, anoxic, and anaerobic zones from top to bottom within the rain garden. This provides a good living environment for different functional microbial communities. The purification system of plants, composite fillers, and microorganisms within the rain garden system exerts physical, chemical, and biological effects. Organic matter and total phosphorus in the initial rainwater can be fully utilized by microorganisms, and ammonia nitrogen can be converted into nitrogen gas and completely removed through nitrification and denitrification, thereby improving the purification efficiency of initial rainwater pollution.
[0066] The electric valve G2 opens after a set number of days, and the purified rainwater flows into the recycled water tank C. The recycled water pipe F4 is connected to the rain garden water replenishment system and the surrounding green space irrigation system to realize the recycling and reuse of rainwater. On the one hand, it is used to replenish water for the plants in the rain garden during the rain interval to ensure the normal use of the rain garden. On the other hand, it is also used as a water source for watering the surrounding green spaces, realizing the conservation and utilization of water resources.
[0067] The ultrasonic level gauge E detects a drop in the liquid level in the level control well B. When the liquid level stops dropping, it sends a closing command to the electric valve G2 and then waits for the next rainfall to arrive, thus realizing a continuous cycle processing function.
[0068] The content of this utility model is not limited to the embodiments listed. Any equivalent modifications made by those skilled in the art to the technical solution of this utility model after reading this utility model specification shall be covered by the claims of this utility model.
Claims
1. A purification device for diverting and treating runoff rainwater pollution, characterized in that: The rain garden includes a structure consisting of plants J1, planting soil J2, composite filler J3, and pebbles J4 arranged from top to bottom. A permeable geotextile K1 is installed between the planting soil J2 and the composite filler J3, and between the composite filler J3 and the pebbles J4. An impermeable membrane K2 is installed at the bottom of the pebbles J4. The rain garden is equipped with a liquid level control well B, and the liquid level control well B is equipped with an overflow well A. The cobblestone J4 is provided with a perforated pipe F1, which is connected to the liquid level control well B. The bottom of the liquid level control well B is connected to the recycled water tank C through the liquid level control well outlet pipe F3. The bottom of the overflow well A is connected to the rainwater inspection well via the overflow well outlet pipe F2.
2. The purification device for diverting and treating runoff rainwater pollution according to claim 1, characterized in that: A duckbill valve G1 is installed on the overflow well outlet pipe F2.
3. The purification device for diverting and treating runoff rainwater pollution according to claim 2, characterized in that: An ultrasonic level gauge E is installed at the bottom of the top plate of the well chamber of the level control well B.
4. The purification device for diverting and treating runoff rainwater pollution according to claim 3, characterized in that: A reclaimed water lift pump D is installed at the bottom of the reclaimed water tank C.
5. A purification device for diverting and treating runoff rainwater pollution according to claim 4, characterized in that: The recycled water booster pump D is connected to the recycled water pipe F4.
6. A purification device for diverting and treating runoff rainwater pollution according to claim 5, characterized in that: The recycled water pipe F4 is connected to the rain garden water replenishment system and the surrounding green space irrigation system.
7. A purification device for diverting and treating runoff rainwater pollution according to claim 6, characterized in that: The recycled water booster pump D is fixed to the top plate of the recycled water tank via guide rail H.
8. A purification device for diverting and treating runoff rainwater pollution according to claim 7, characterized in that: The recycled water pipe F4 is fixed to the side wall of the recycled water tank C by pipe clamp I.