Ceramsite cushion layer filling structure of horizontal subsurface flow wetland

Abstract

The utility model relates to a ceramsite cushion layer filling structure of a horizontal subsurface flow wetland, which comprises a water inlet area, a main body area and a water outlet area which are sequentially arranged along the water flow direction, each layer of the horizontal subsurface flow wetland adopts zongzi-shaped ceramsite as a filler, and the appearance of the zongzi-shaped ceramsite is a tetrahedron-like shape with micropores inside and slightly convex and hardened outside. The grain sizes of the zongzi-shaped ceramsite are respectively 15-25mm, 10-15mm and 4-8mm, the grading of the 15-25mm zongzi-shaped ceramsite in the water inlet area reaches 50% of porosity, the grading of the 4-8mm zongzi-shaped ceramsite in the main body area reaches 40% of porosity, and the grading of the 10-15mm zongzi-shaped ceramsite in the water outlet area reaches 55% of porosity. According to the utility model, the zongzi-shaped ceramsite is mixed and graded to form the wetland cushion layer with moderate porosity, so that medium conditions are effectively provided for plant growth and microorganism attachment, and a complex medium environment formed by the large specific surface area of the zongzi-shaped ceramsite and the pore space integrally enhances the adsorption and interception effects of the filler; and the use and replacement time of the wetland filler is also prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to a ceramsite cushion layer structure, in particular to a ceramsite cushion layer filling structure of horizontal subsurface flow wetland. BACKGROUND

[0002] Wetland filler is an indispensable part of the wetland system, which not only provides a basic environment for the growth of plants and microorganisms, but also removes pollutants through direct and indirect action.

[0003] Subsurface flow wetland construction and low-impact development retention facilities require filler cushion, and the structural characteristics, particle size and grading of wetland filler directly determine the hydraulic conductivity of the wetland matrix, which is one of the main factors affecting wetland clogging. The larger the particle size of the matrix filler, the more porous the structure, the more reasonable the grading, and the better the void fraction and hydraulic conductivity of the filler.

[0004] In engineering construction, gravel is generally used as the preferred matrix filler for subsurface flow wetland treatment systems due to its wide source, easy availability and relatively low cost, but it has problems such as easy clogging, difficult vegetation growth or poor pollutant removal effect. Therefore, it is necessary to study a new ceramsite cushion layer filling structure to solve the problems of clogging, vegetation growth or poor pollutant removal effect in horizontal subsurface flow wetlands. SUMMARY

[0005] The utility model aims at providing a ceramsite cushion layer filling structure for horizontal subsurface flow wetlands, which can provide more growth space for the extension of plant root systems in horizontal subsurface flow wetlands, ensure good permeability of the cushion layer, promote uniform distribution of water flow in horizontal subsurface flow wetlands, reduce water flow short-circuiting phenomenon, thereby improving the stability of the horizontal subsurface flow wetland system and ensuring the water quality treatment effect of the horizontal subsurface flow wetland.

[0006] To achieve the above-mentioned purpose, the utility model provides a ceramsite cushion layer filling structure for horizontal subsurface flow wetlands, which comprises a water inlet area, a main body area and a water outlet area arranged in sequence along the water flow direction, and uses zong-shaped ceramsite as the filler for each layer of the horizontal subsurface flow wetland. The zong-shaped ceramsite has a tetrahedron-like shape with internal micropores and an externally convex hardened surface. The particle sizes of the zong-shaped ceramsite are 15-25 mm, 10-15 mm and 4-8 mm. In the water inlet area, the 15-25 mm zong-shaped ceramsite is graded to achieve 50% porosity, in the main body area, the 4-8 mm zong-shaped ceramsite is graded to achieve 40% porosity, and in the water outlet area, the 10-15 mm zong-shaped ceramsite is graded to achieve 55% porosity.

[0007] Preferably, the water inlet area is filled with 15 mm, 20 mm and 25 mm zong-shaped ceramsite, and the bulk density of the 15 mm, 20 mm and 25 mm zong-shaped ceramsite is 400 kg / m 3, 350kg / m 3 , 300kg / m 3 .

[0008] Preferably, the main body area is filled with 4mm, 6mm and 8mm zong-shaped ceramsite gradation, wherein the 4mm, 6mm and 8mm zong-shaped ceramsite bulk densities are 800kg / m 3 , 700kg / m 3 , 650kg / m 3 .

[0009] Preferably, the water outlet area is filled with 10mm, 12mm and 15mm zong-shaped ceramsite gradation, wherein the 10mm, 12mm and 15mm zong-shaped ceramsite bulk densities are 600kg / m 3 , 550kg / m 3 , 400kg / m 3 .

[0010] Based on the above technical scheme, the horizontal subsurface flow wetland's ceramsite cushion filling structure has the following advantages:

[0011] The horizontal subsurface flow wetland's ceramsite cushion filling structure adopts zong-shaped ceramsite as the filler, which not only maintains the porous inner core and hard shell of general ceramsite, but also has the characteristics of not easy to roll, stable stacking body, and adjustable porosity of the stacking body, so that it can meet the wide application requirements of general ceramsite, and can be used for the subsurface flow wetland filler cushion and the low-impact development retention facility cushion according to the needs, thereby improving the environmental governance and ecological restoration quality effect.

[0012] The ceramsite cushion filling structure adopts zong-shaped ceramsite as the filler, and the tetrahedron-like zong-shaped ceramsite has a larger specific surface area and a wider porosity adjustment possibility; the zong-shaped ceramsite with a larger specific surface area can attach more microorganisms, and the wide porosity can not only provide a larger growth space for the extension of the subsurface flow wetland plant root system, but also can ensure that the cushion has good permeability, promote the uniform distribution of water flow in the subsurface flow wetland, and reduce the water flow short flow phenomenon, thereby improving the stability of the subsurface flow wetland system and ensuring the water quality treatment effect of the subsurface flow wetland. BRIEF DESCRIPTION OF DRAWINGS

[0013] The drawings described herein are used to provide a further understanding of the present application, and constitute a part of the present application. The schematic embodiments of the present application and the descriptions thereof are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0014] Figure 1 It is a schematic diagram of the ceramsite cushion filling structure of the horizontal subsurface flow wetland;

[0015] Figure 2 It is a schematic diagram of the zong-shaped ceramsite shape. DETAILED DESCRIPTION

[0016] The technical scheme of the utility model is further described in detail below with reference to the drawings and examples.

[0017] The utility model provides a kind of ceramsite cushion filling structure of horizontal subsurface flow wetland, as shown in Figure 1 It includes water inlet area 1, main body area 2, water outlet area 3 sequentially arranged along water flow direction, each layer of the horizontal subsurface flow wetland uses zong-shaped ceramsite as filler, the shape of the zong-shaped ceramsite is tetrahedron type with internal micropore and microconvex hardening on the outside, the particle size of the zong-shaped ceramsite is 15-25mm, 10-15mm and 4-8mm three kinds of gravel diameter grade, 15-25mm zong-shaped ceramsite is graded to reach 50% porosity in water inlet area 1, 4-8mm zong-shaped ceramsite is graded to reach 40% porosity in main body area 2, 10-15mm zong-shaped ceramsite is graded to reach 55% porosity in water outlet area 3.

[0018] Compared with egg-shaped ceramsite, the zong-shaped ceramsite with tetrahedron type has larger specific surface area and wider porosity adjustment possibility, the zong-shaped ceramsite with larger specific surface area can attach more microorganisms, the wide porosity can not only provide larger growth space for the extension of subsurface flow wetland plant root system, but also can ensure that the cushion has better permeability, promote the uniform distribution of water flow in subsurface flow wetland, reduce water flow short flow phenomenon, thereby improve the stability of subsurface flow wetland system and guarantee the water quality treatment effect of subsurface flow wetland. The zong-shaped structure ceramsite with tetrahedron type solves the problems of poor purification effect and easy clogging of existing gravel cushion caused by small specific surface area and insufficient porosity.

[0019] The zong-shaped ceramsite is manufactured by using roller granulation and calcination technology, and specifically, the preparation of the zong-shaped ceramsite includes: forming tetrahedron gravel embryo by roller compaction granulation of prepared high-moisture powder ash, and then calcining the tetrahedron gravel embryo to form zong-shaped ceramsite with internal micropore and microconvex hardening on the outside. The prepared high-moisture powder ash is formed into tetrahedron gravel embryo by roller compaction granulation, and the calcination process produces zong-shaped particle artificial ceramic gravel with internal micropore and microconvex hardening on the outside, as shown in Figure 2 .

[0020] The tetrahedron particle needs special granulation equipment, and the zong-shaped ceramsite mold is relatively simple, and the calcination process is similar to ordinary ceramsite, and both can be mass-produced to become special cushion material. Further, due to the wider porosity adjustment possibility, the zong-shaped ceramsite with tetrahedron type can be mixed according to the application scene needs to achieve different permeability porosity accumulation body.

[0021] Preferably, the water inlet area 1 is filled by 15mm, 20mm and 25mm zong-shaped ceramsite grading, and the bulk density of 15mm, 20mm and 25mm zong-shaped ceramsite is 400kg / m 3, 350 kg / m 3 , 300 kg / m 3 . Preferably, the main body area 2 is filled with 4mm, 6mm and 8mm zong-shaped ceramic particle grading, wherein the 4mm, 6mm and 8mm zong-shaped ceramic particle bulk density is 800 kg / m 3 , 700 kg / m 3 , 650 kg / m 3 . Preferably, the water outlet area 3 is filled with 10mm, 12mm and 15mm zong-shaped ceramic particle grading, wherein the 10mm, 12mm and 15mm zong-shaped ceramic particle bulk density is 600 kg / m 3 , 550 kg / m 3 , 400 kg / m 3 .

[0022] Specifically, zong-shaped ceramic particles are used for horizontal subsurface flow wetlands:

[0023] (1) Prepare brown-shaped ceramic gravel with the following particle size and bulk density respectively, and wash it clean:

[0024]

[0025] According to the horizontal subsurface flow wetland layout, divide the wetland structure unit, and draw the water inlet area 1, main body area 2, water outlet area 3 filler design width horizontal line and filler height horizontal line in each wetland unit according to the design filler width, as filler paving marks;

[0026] Mix the 15mm, 20mm and 25mm brown-shaped ceramic gravel obtained in (1) in a mass ratio of 2:2:6, and then uniformly lay them to the water inlet area filler width mark;

[0027] Mix the 4mm, 6mm and 8mm brown-shaped ceramic gravel obtained in (1) in a mass ratio of 3:3:4, and then uniformly lay them to the main body area of the filler by artificial paving;

[0028] Mix the 10mm, 12mm and 15mm brown-shaped ceramic gravel obtained in (1) in a mass ratio of 2:2:6, and then uniformly lay them to the water outlet area filler width mark;

[0029] The subsurface flow wetland filler layer needs to be laid in combination with the construction of the impermeable layer, pipeline laying, geotechnical material laying, wall building and other processes. After completion, water test and operation can be carried out.

[0030] The wetland filler filling structure of the utility model is formed by the zong-shaped haydite mixed gradation, which effectively provides medium conditions for plant growth and microorganism adhesion, and the pollutants are intercepted due to the mechanical blocking effect of the zong-shaped haydite, such as filtration, sedimentation and adsorption, and the large specific surface area of the zong-shaped haydite and the complex medium environment formed by the microorganism attached in the pore space and the plant root system as a whole enhances the adsorption and interception effect of the filler, and simultaneously prolongs the replacement time of the wetland filler. As the low-impact development retention facility infiltration filler layer, the zong-shaped haydite is mixed and graded to form a rainwater garden base layer with moderate permeability, which blocks floating objects and adsorbs suspended objects when rainwater flows, and simultaneously supports emergent plants and their growth substrates.

[0031] It should be finally pointed out that: the above examples are only used to illustrate the technical solutions of the utility model and not to limit them; although the utility model has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that: the specific embodiments of the utility model can still be modified or some technical features can be replaced by equivalents; without departing from the spirit of the technical solutions of the utility model, they should be covered in the technical solution range of the utility model claimed.

Claims

1. A ceramsite cushion layer filling structure for a horizontal subsurface flow wetland, characterized in that: The system includes an inlet zone (1), a main body zone (2), and an outlet zone (3) arranged sequentially along the water flow direction. Each layer of the horizontal subsurface flow wetland uses zongzi-shaped ceramsite as filler. The zongzi-shaped ceramsite has a tetrahedral shape with internal micropores and a slightly convex hardened exterior. The zongzi-shaped ceramsite has three gravel sizes: 15-25 mm, 10-15 mm, and 4-8 mm. In the inlet zone (1), the 15-25 mm zongzi-shaped ceramsite is graded to achieve 50% porosity. In the main body zone (2), the 4-8 mm zongzi-shaped ceramsite is graded to achieve 40% porosity. In the outlet zone (3), the 10-15 mm zongzi-shaped ceramsite is graded to achieve 55% porosity.

2. The ceramsite cushion layer filling structure according to claim 1, characterized in that: The water inlet zone (1) is filled with 15mm, 20mm and 25mm shaped ceramsite, with a bulk density of 400kg / m³ for each of the 15mm, 20mm and 25mm shaped ceramsite. 3 350kg / m 3 300kg / m 3 .

3. The expanded clay aggregate cushion layer filling structure according to claim 1, characterized in that: The main body area (2) is filled with 4mm, 6mm and 8mm shaped ceramsite, with a bulk density of 800 kg / m³ for the 4mm, 6mm and 8mm shaped ceramsite respectively. 3 700kg / m 3 650kg / m 3 .

4. The expanded clay aggregate cushion layer filling structure according to claim 1, characterized in that: The effluent zone (3) is filled with 10mm, 12mm and 15mm shaped ceramsite, with a bulk density of 600 kg / m³ for each of the 10mm, 12mm and 15mm shaped ceramsite. 3 550kg / m 3 400kg / m 3 .

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