CN102251459A - System for carrying out collection, purification and utilization on rainwater on road surfaces - Google Patents

Abstract

The invention provides a pavement rainwater collection, storage, purification and utilization system, which includes a trench and one or more packing units arranged in the trench, each packing unit is provided with baffles on both sides, and two adjacent packing units start and end An air well is formed between the two baffles at the end of the groove, and an air well is formed between the baffles at both ends of the groove and the inner wall of the groove; a concrete grate is arranged on the bottom surface of each packing unit, and there is a concrete grate between the concrete grate and the inner bottom surface of the groove. A sump is formed, and the sump communicates with all the ventilation wells; the filling unit on the concrete grate is composed of a pebble layer, a gravel layer, a substrate layer and a planting soil layer arranged in sequence from bottom to top, and plants are planted on the planting soil layer . After the rainwater is purified by the system of the present invention, it can meet the needs of agricultural water and general landscape water.

Description

A pavement rainwater collection, storage, purification and utilization system

technical field

The invention belongs to the technical field of rainwater collection, storage, purification and utilization, and in particular relates to a road surface rainwater storage, purification and utilization system.

Background technique

Water resources are very important and special natural resources, the basic material that human beings rely on for survival and the restrictive factor of human sustainable development. As the world's population expands, water scarcity has become a global threat. China is a developing country with poor water resources, with a per capita water volume of 2400-2500 m ³ /a, which is a quarter of the world's per capita water volume. At the same time, my country is also facing serious water pollution problems. There are two main types of water pollution: point source pollution (Point Source Pollution) and non-point source pollution (Non-point Source Pollution). Non-point source pollution mainly refers to the water pollution caused by pollutants in the atmosphere, ground and soil entering rivers, lakes, reservoirs and oceans under the leaching and scouring of rainfall runoff (including irrigation). Also known as non-point source pollution, it is ubiquitous. According to the source of non-point source pollution, it can be divided into urban non-point source and agricultural non-point source. Urban non-point source pollution increases with the increase of urbanization level. The U.S. Environmental Protection Agency (USEPA) has listed urban runoff as the third leading source of pollution in rivers and lakes across the United States.

At present, the shortage of urban water resources and water pollution problems need to be solved urgently, and rainwater, as the most fundamental, most direct and most economical water resource, is the primary measure for "opening up sources of income and reducing expenditure". At the same time, practice at home and abroad has proved that ecological technology is one of the fundamental ways to solve non-point source pollution. The ecological technology of non-point source pollution control is mainly a measure to control pollutants by controlling the material balance and material flow of the ecosystem, making full use of the purification capabilities of land, vegetation and water bodies, and intercepting nitrogen, phosphorus, sediment and other substances. Ecological technology has the advantages of low cost, multiple benefits, and suitability for various conditions. It is a practical and effective way to control non-point source pollution.

It can be seen that it is necessary to use ecological technology to research and develop a new type of rainwater collection, storage, purification and utilization device to collect, treat and reuse urban rainfall runoff, so as to achieve the dual purposes of developing fresh water resources and controlling urban non-point source pollution. Constructed wetland is an earlier ecological technology for rainwater collection, storage, purification and utilization. It uses the triple synergy of physics, chemistry and biology in the natural ecosystem to purify the incoming raw water. It is currently the cheapest low-investment, low-energy, and effective water treatment system in the world. It is a method that is very suitable for green city construction, ecological environment protection, domestic sewage purification, and rainwater collection and purification.

Constructed wetland treatment devices mainly include horizontal flow constructed wetland treatment bed and vertical flow constructed wetland treatment bed. The height of the horizontal subsurface flow constructed wetland bed is about 0.6~0.8m, and relatively coarse substrate such as gravel is used as the treatment medium. Horizontal flow, and plant large emergent plants with oxygen-secreting capacity in the matrix layer, such as reeds, cattails and water onions, etc., using the oxygen-secreting capacity of aquatic plants to provide oxygen for the biofilm on the substrate of the constructed wetland to decompose the organic matter in the raw water . The height of the vertical flow artificial wetland bed is more than 1.0m, and a finer substrate such as sand is usually used as the infiltration medium. The raw water is treated in the process of vertical infiltration from the surface downward, and most of the plants used are reeds, windmills and sweetgrass root grass etc.

The shortcomings are: (1) The horizontal flow artificial wetland treatment bed has shortcomings such as insufficient aerobic conditions, although it can remove SS well and some BOD. However, he is usually not effective in removing ammonia nitrogen. Because it cannot complete the nitrification process of most wastewater, even if it has a strong denitrification ability, it cannot independently complete the two treatment processes of wastewater nitrification and denitrification to achieve the purpose of wastewater denitrification treatment. (2) The vertical flow constructed wetland treatment bed has stronger treatment capacity and nitrification capacity for aerobic organic matter in wastewater, and it has better aerobic conditions than horizontal flow constructed wetland, and the removal effect of BOD ₅ and COD in wastewater is both It is better, but its removal effect on SS is worse than that of horizontal flow constructed wetland, and it is very prone to clogging; although it has a strong nitrification ability for wastewater, its denitrification ability is also worse than that of horizontal flow constructed wetland, so it cannot The two treatment processes of nitrification and denitrification of wastewater are completed separately to achieve the purpose of wastewater denitrification treatment. (3) Both the vertical flow constructed wetland treatment bed and the horizontal flow constructed wetland treatment bed have poor phosphorus removal capabilities in raw water (<30-40%), and the currently widely used sand, gravel and other substrates have poor phosphorus removal capabilities. The service life of adsorption saturation is short, generally 2 to 3 years: even if the horizontal flow constructed wetland and the vertical flow constructed wetland are connected in series to form a composite system, if sand and gravel substrates are still used, the removal rate of phosphorus is still less than 60%. (4) The current constructed wetland treatment beds are generally closed circular or square, occupy a large area, and need a large area of open space to complete the construction of constructed wetlands. The construction conditions are limited and cannot be widely used. (5) At present, most of the plants used in constructed wetlands are annual shrubs or herbaceous plants. The treatment effect in summer is ideal, but when the plants wither in winter, not only the treatment effect is affected, but also the appearance is affected.

Contents of the invention

The purpose of the present invention is to provide a pavement rainwater collection, storage, purification and utilization system, which is an urban road rainwater collection and purification treatment facility rebuilt based on vertical flow artificial wetlands. The treated water can be directly reused for urban municipal and landscape water after collection . the

The technical solution adopted in the present invention is a pavement rainwater collection, storage, purification and utilization system, which includes a groove and one or more packing units arranged in the groove, and baffle plates are respectively arranged on both sides of each packing unit, corresponding An air well is formed between the two baffles adjacent to the head and tail ends of the two packing units, and an air well is formed between the baffles at both ends of the groove and the inner wall of the groove; a concrete grate is arranged on the bottom of each packing unit, and the concrete grate is connected to the inner wall of the groove. A water collection tank is formed between the inner bottom of the trench, and the water collection tank communicates with all the ventilation wells; the filling unit on the concrete grate is composed of a pebble layer, a gravel layer, a matrix layer and a planting soil layer arranged in sequence from bottom to top. Plants are planted on the soil layer.

Wherein, the water collection tank is arranged in an inclined manner.

Wherein, the lower end of the sump is provided with a water outlet pipe communicating with the outside world.

It is also characterized in that the thickness of the cobblestone layer is 0.05-0.2m, the thickness of the gravel layer is 0.1-0.3m, the thickness of the matrix layer is 0.1-0.3m, and the thickness of the planting soil layer is 0.2-0.5m; The thickness is 0.45-1.3m.

Wherein, the matrix layer is a fly ash layer, a blast furnace slag layer, a zeolite layer or a mixture layer; the mixture layer is a mixture of any two or three of fly ash, blast furnace slag and zeolite in any proportion.

It is further characterized in that a plurality of air ducts are arranged in each packing unit, the bottom of the air ducts is located on the upper surface of the cobblestone layer, and the top of the air ducts is higher than the upper surface of the planting soil layer; the length of the air ducts located in the packing units is H, there are multiple small holes on the ventilation pipe between the upper surface of the planting soil layer and the 1/8H downward from the upper surface of the planting soil layer, and between the upper surface of the pebble layer and the 2/5H upward from the upper surface of the pebble layer There are many small holes on the ventilation pipe.

Wherein, the upper end of the baffle is higher than the upper surface of the planting soil layer.

The beneficial effect of the present invention is,

1. Based on the vertical flow constructed wetland, the raw water flows through all the filler layers, which has a better treatment effect than the horizontal subsurface flow constructed wetland, with high treatment efficiency and strong impact load resistance. Cobblestone, gravel, fly ash (or blast furnace slag or zeolite or their combination), planting soil and other matrix fillers are used in the filler layer to reduce the pollution of organic matter, nitrogen (N), phosphorus (P), heavy metals and other pollutants in raw water. It has strong processing ability. The removal rate of chemical oxygen demand (COD) is 50%~70%, the removal rate of total nitrogen (TN) is 40%~60%, and the removal rate of ammonia nitrogen (NH ₃ -N) is about 50%. The removal rate of soluble orthophosphate (DP) is 70%~90%, the removal rate of total phosphorus (TP) is 70%~90%, and the removal rate of heavy metal lead (Pb) is 30%~40%. The removal rate of heavy metal chromium (Cr) is 20%~30%, and the removal rate of heavy metal cadmium (Cd) is 30%~40%. At the same time, the system is closely integrated with urban greening, and its application range is expanded to fully and effectively utilize rainwater. After purification by the system of the present invention, total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH ₃ -N), chemical oxygen demand (COD), suspended solids (SS), heavy metals (mainly lead, chromium) in the effluent , cadmium) and other main water quality indicators are aimed at the initial rainwater of rainfall runoff, and the effluent can basically meet the "Urban Sewage Recycling Urban Miscellaneous Water Quality" (GB/T18920-2002) and "Urban Sewage Recycling Landscape Water Quality" (GB/T18921-2002 ) related requirements. For the rainwater in the middle and late stages of rainfall runoff, the effluent can basically meet the water quality of Class V in the "Environmental Quality Standards for Surface Water" (GB 3838-2002), so as to meet the needs of agricultural water and general landscape water.

2. By setting up ventilation wells and ventilation pipes to increase the intensity of atmospheric reoxygenation, the phenomenon of water quality deterioration and odor caused by anaerobic bottom of the vertical flow artificial wetland is avoided, and the quality of effluent water is guaranteed.

Description of drawings

Fig. 1 is the top view of a packing unit arranged in the trench of the pavement rainwater collection, storage, purification and utilization system of the present invention;

Fig. 2 is a longitudinal sectional view of a packing unit arranged in the groove of the pavement rainwater collection, storage, purification and utilization system of the present invention;

Fig. 3 is a longitudinal sectional view of a plurality of packing units arranged in the groove of the pavement rainwater collection, storage, purification and utilization system of the present invention;

Fig. 4 is a schematic diagram of the road surface rainwater collection, purification and utilization system of the present invention being set in the middle of the road;

Fig. 5 is a schematic diagram of the road surface rainwater collection, storage, purification and utilization system of the present invention arranged on both sides of the road;

Fig. 6 is a structural schematic diagram of the ventilation pipe buried in the packing unit.

In the figure, 1. trench, 2. baffle, 3. ventilation well, 4. concrete grate, 5. sump, 6. cobblestone layer, 7. gravel layer, 8. substrate layer, 9. planting soil layer, 10. Outlet pipe, 11. Ventilation pipe, 12. Metal filter screen, 13. Road rainwater collection and purification utilization system, 14. Road.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Fig. 1 and Fig. 2, the present invention provides a pavement rainwater collection, storage, purification and utilization system, which includes a groove 1 and a packing unit arranged in the groove 1, and baffles 2 are respectively arranged on both sides of the packing unit, A ventilation shaft 3 is formed between the baffle plate 2 and the inner wall of the groove 1; a concrete grate 4 is arranged on the bottom surface of the packing unit, and a water collection tank 5 is formed between the concrete grate 4 and the inner bottom surface of the groove 1, and the water collection tank 5 and two ventilation shafts The wells 3 communicate with each other to form a "U"-shaped ventilation corridor; the water collection tank 5 is arranged obliquely, with a slope of 0.01~0.015 (11), and the lower end of the water collection tank 5 is provided with an outlet pipe 10 communicating with the outside world.

The rainwater collection, purification and utilization system of the present invention can be arranged in the middle or both sides of the road 14, and a plurality of packing units are arranged in the trench 1 according to the required length, as shown in Fig. 3, the two sides of each packing unit are respectively arranged There are baffles 2, an air well 3 is formed between the two baffles 2 at the head and tail ends of two adjacent packing units, and an air well 3 is also formed between the baffles 2 at both ends of the groove 1 and the inner wall of the groove 1; each A concrete grate 4 is arranged on the bottom surface of the packing unit, and a sump 5 is formed between the concrete grate 4 and the inner bottom of the groove 1, and the sump 5 communicates with all the ventilation wells 3, and the sump 5 is arranged on an incline, with a slope of 0.01~ 0.015 (11), the lower end of the sump 5 is provided with an outlet pipe 10 communicating with the outside world.

The filler unit on the concrete grate 4 consists of a pebble layer 6 with a thickness of 0.05-0.2m, a gravel layer 7 with a thickness of 0.1-0.3m, a matrix layer 8 with a thickness of 0.1-0.3m and a thickness of 0.1-0.3m. It is composed of 0.2-0.5m planting soil layer 9; the particle size of cobblestone is 50-100mm, the particle size of gravel is 10-30mm, and the particle size of planting soil is 2-5mm; the matrix layer 8 is powder with a particle size of 1-3mm Coal ash layer, blast furnace slag layer with a particle size of 5-10mm, zeolite layer with a particle size of 3-5mm or a mixture layer with a particle size of 3-8mm, the mixture layer is any two or more of fly ash, blast furnace slag, and zeolite Mixtures in any proportion. Each layer is separated by geotextiles, so as to prevent fine particles from migrating downward with the treated water and blocking the filter material of the lower layer or entering the bottom sump 5, affecting the quality of effluent water or ventilation effect. A plurality of ventilation pipes 11 are arranged in each packing unit. The upper end of the baffle plate 2 is higher than the planting soil layer 9, so as to prevent the raw water from permeating slowly and causing overflow so that the raw water directly flows into the aeration sump 5 at the bottom without treatment. Vent shaft 3 upper end cover is provided with metal filter screen 12, in order to avoid road surface sediment to fall into. The planting soil layer 9 is used for planting plants, which are commonly used greening plants on urban roads, such as privet privet, boxwood, radix radix and calamus. The roots of plants can not only produce oxygen, but also provide an environment for the growth of microorganisms. Thereby improving the removal effect of the system on N, P, heavy metals and other pollutants. The matrix layer 8 is used to adsorb and remove pollutants such as N, P, and heavy metals, the gravel layer 7 is used to adsorb phosphorus, and the pebble layer 6 mainly plays a supporting role and can also adsorb a small amount of P.

The rainwater collection, storage, purification and utilization system of the present invention can be arranged in the middle or both sides of the road 14, and the road surface of the city or residential area is used as the reference during construction. , the rainwater has no time to infiltrate and overflow; while the top of the air well 3 needs to be 5~20cm higher than the road surface to prevent the rainwater runoff on the road from entering the bottom sump 5 along the air well 3 and affecting the water quality of the effluent of the trench 1. At the same time, add water to the top of the air well 3 Covering the metal screen 12, on the one hand, for the sake of beauty and safety, on the other hand, can prevent road surface sediment from entering the bottom sump through the air shaft 3 and cause the sump to be blocked.

The rainwater passes through the lateral gradient of the road surface, as shown in Figure 4, when the road surface rainwater storage and purification utilization system 13 of the present invention is arranged in the middle of the road 14 in the city or community, the rainwater will sink from both sides of the system of the present invention with bilateral (i.e. road surface runoff) into the road surface rainwater collection and purification utilization system 13 of the present invention; as shown in Figure 5, when the road surface rainwater collection and purification utilization system 13 of the present invention is arranged on both sides of the city or community road 14, The rainwater is imported into the road surface rainwater collection and purification utilization system 13 of the present invention in a unilateral manner (that is, the road surface runoff flows into the system from one side of the present invention); the rainwater is filtered by the packing unit and then passed through the concrete grate 4 sink Into the sump 5, because the sump 5 is provided with a certain slope, the filtered rainwater extends along the sump 5, and is discharged to the water storage place through the outlet pipe 10, and finally reused, and the reused rainwater can be used for urban greening. The main purpose of arranging the ventilation shaft 3 is to facilitate the ventilation of the sump 5 and prevent the treated water from going bad and smelly. As shown in Figure 6, a plurality of ventilation ducts 11 are arranged in each packing unit, and the pipe diameter is 50mm. Prevent raw water from entering. The air duct 11 buried in the filler unit has a length of H, and a plurality of small holes are arranged on the air duct 11 between the upper surface of the planting soil layer 9 and the downward 1/8H of the upper surface of the planting soil layer 9. There are multiple small holes on the air duct 11 between the upper surface of the 6 and the upper surface of the cobblestone layer 6 at 2/5H upwards. The diameter of the small holes is 5 mm, and the hole spacing is 2.5 cm. Provide ventilation conditions, so that the packing unit can achieve the oxygen distribution law of aerobic-facultative-anaerobic-facultative-aerobic, alleviate the phenomenon of deterioration and odor of treated water caused by anaerobic, and ensure the quality of effluent water.

Based on the vertical flow artificial wetland, the present invention mainly changes the oxygen distribution state inside the system and the collection method of treated water to ensure the water quality of the effluent; the present invention arranges the filling unit in the groove 1, and the shape of the groove 1 is long and narrow , can be applied to the middle and both sides of the urban road 14 in production practice, and its application range has been expanded compared with the constructed wetland. In addition, by setting the ventilation well 3 and the ventilation pipe 11 to increase the intensity of atmospheric reoxygenation, the phenomenon of water quality deterioration and odor caused by anaerobic bottom of the vertical flow constructed wetland is avoided, and the quality of the effluent water is guaranteed. The greening plants commonly used on urban roads that are evergreen in all seasons are used as the planting plants of the system of the present invention to provide a suitable growth environment for microorganisms, and then assist the system as a whole to improve the purification ability of pollutants in rainfall runoff. At the same time, when winter comes, without affecting the city In the case of beautiful appearance, the water quality of the system effluent is guaranteed, so that the control of urban non-point source pollution and the collection, purification and utilization of rainwater are closely combined with urban greening, which has a good development prospect and is suitable for popularization and use.

The effect of the pavement rainwater collection, storage, purification and utilization system of the present invention will be further described by tests below:

The test is divided into five groups: the raw water enters the road surface rainwater collection, storage, purification and utilization system of the present invention through the water distribution bucket and the water distribution pipe on both sides. 5; the cobblestone layer 6 at an elevation of 100-200mm, with a particle size of 50-100mm; the gravel layer 7 at an elevation of 200-450mm, with a particle diameter of 10-30mm; the matrix layer 8 at an elevation of 450-650mm (Group 1 is fly ash, Particle size is 1~3mm; group 2 is blast furnace slag, particle size is 5~10mm; group 3 is zeolite, particle size is 3~5mm; group 4 is blast furnace slag and zeolite mixed at a volume ratio of 1:1, particle size 3~8mm; group 5 is a mixture of fly ash, blast furnace slag and zeolite in a volume ratio of 1:1:1, with a particle size of 3~8mm); the elevation 650~950mm is planting soil layer 9, with a particle size of 2~ 5mm; the elevation of 950~1050mm is super high (to prevent raw water from overflowing).

Test 1: The raw water is distributed according to the initial rainfall data of rainfall and runoff. The chemical oxygen demand (COD) is 453.66mg/L, the ammonia nitrogen (NH ₃ -N) is 2.97mg/L, and the total nitrogen (TN) is 16.12mg/L. Soluble orthophosphate (DP) is 1.15mg/L, total phosphorus (TP) is 5.19mg/L, heavy metal lead (Pb) is 0.36mg/L, heavy metal chromium (Cr) is 0.32mg/L, heavy metal cadmium (Cd) ) is 0.018mg/L. The operating hydraulic load is 2.0m ³ /m ² ·d. Through the treatment of the system of the present invention, the effluent basically meets the relevant requirements of "Urban Sewage Recycling Urban Miscellaneous Water Quality" (GB/T18920-2002) and "Urban Sewage Recycling Landscape Water Quality" (GB/T18921-2002). The removal rate (Test 1) of the five groups of tests for each pollutant index is shown in Table 1:

Experiment 2: The raw water is distributed according to the rainwater data in the middle and late stages of rainfall runoff. The chemical oxygen demand (COD) is 138.65mg/L, the ammonia nitrogen (NH ₃ -N) is 1.45mg/L, and the total nitrogen (TN) is 5.76mg/L. , soluble orthophosphate (DP) is 0.32mg/L, total phosphorus (TP) is 1.38mg/L, heavy metal lead (Pb) is 0.15mg/L, heavy metal chromium (Cr) is 0.12mg/L, heavy metal cadmium ( Cd) is 0.015mg/L. The test equipment used is the same as that of Test 1. The operating hydraulic load is 2.0m ³ /m ² ·d. Through the treatment of the system of the present invention, the effluent basically reaches the water quality of Class V in the "Environmental Quality Standard for Surface Water" (GB 3838-2002), which can meet the needs of agricultural water and general landscape water. The removal rate (Test 2) of the five groups of tests for each pollutant index is shown in Table 2:

From the comparison of the removal effects of the above two groups of tests, it can be seen that the removal effect of the system of the present invention for rainfall runoff pollutants is relatively stable. For rainwater in different stages of rainfall runoff (initial and middle and late stages), the experimental device filled with fly ash matrix has the best removal effect on soluble orthophosphate (DP), and the removal rate can reach about 85%. The removal rate of soluble orthophosphate (DP) and total phosphorus (TP) in the experimental device filled with blast furnace slag matrix or zeolite matrix can reach about 80%. For COD and NH ₃ -N The removal effect is better, which can reach about 55% or 75% and about 45% or 70%, respectively; the removal effects of the above five sets of devices for heavy metals Pb, Cr, and Cd can reach about 35%, 25%, and 35% respectively. The experimental device filled with blast furnace slag and zeolite 1:1 mixed filler and fly ash, blast furnace slag, zeolite mixed filler in 1:1:1 has better removal effect on each pollution index than single filler, and the fly ash , blast furnace slag, and zeolite at a ratio of 1:1:1 mixed with the filler in the experimental device has the most ideal treatment effect. It can be seen that different substrates (fillers) are selective for the removal of various pollutants, and the purification effect can be significantly improved by mixing the fillers.

Claims (7)

1. a road surface rainwater harvests the purification utilization system, it is characterized in that: comprise groove (1) and be arranged on the interior one or more filler units of groove (1), the both sides of each filler unit are respectively arranged with baffle plate (2), form ventilation well (3) between two baffle plates (2) of adjacent two filler unit two ends, form the well (3) of ventilating between the baffle plate (2) that is positioned at groove (1) two ends and groove (1) inside wall; Each filler unit bottom surface is provided with a concrete grate (4), forms catch basin (5) between concrete grate (4) and groove (1) inner bottom surface, and catch basin (5) communicates with each other with all ventilation well (3); Filler unit on the concrete grate (4) is made up of the cobble layer (6) that sets gradually from the bottom up, layer of gravel (7), hypothallus (8) and plantation soil layer (9), and plantation soil layer (9) is gone up to plant and is implanted with plant.

2. road surface according to claim 1 rainwater harvests the purification utilization system, it is characterized in that: described catch basin (5) is inclined to set.

3. road surface according to claim 2 rainwater harvests the purification utilization system, it is characterized in that: the low side of described catch basin (5) is provided with and the extraneous outlet pipe (10) that communicates.

4. road surface according to claim 1 rainwater harvests the purification utilization system, it is characterized in that: the thickness of described cobble layer (6) is 0.05-0.2m, the thickness of layer of gravel (7) is 0.1-0.3m, the thickness of hypothallus (8) is 0.1-0.3m, and the thickness of plantation soil layer (9) is 0.2-0.5m; The gross thickness of filler unit is 0.45-1.3m.

5. harvest the purification utilization system according to claim 1 or 4 described road surface rainwater, it is characterized in that: described hypothallus (8) is fine coal grieshoch, blast furnace slag blanket, zeolite layer or mixture layer; Described mixture layer is any two or three mixture with the arbitrary proportion composition in flyash, blast furnace slag, the zeolite.

6. road surface according to claim 1 rainwater harvests the purification utilization system, it is characterized in that: described each filler unit lining is equipped with many air ducts (11), the bottom of air duct (11) is positioned at the upper surface of cobble layer (6), and the top of air duct (11) is higher than the upper surface of plantation soil layer (9); Air duct (11) length that is positioned at filler unit is H, be provided with a plurality of apertures from plantation soil layer (9) upper surface to the air duct (11) the downward 1/8H of plantation soil layer (9) upper surface, be provided with a plurality of apertures to the air duct (11) that cobble layer (6) upper surface makes progress the 2/5H from cobble layer (6) upper surface.

7. road surface according to claim 1 rainwater harvests the purification utilization system, it is characterized in that: the upper end of described baffle plate (2) is higher than plantation soil layer (9) upper surface.

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