Flexible landfill

Abstract

The utility model discloses a flexible landfill and relates to the technical field of solid waste landfill. The flexible landfill comprises a drainage pipe, a drainage ditch, a soil foundation layer, a bottom face anti-seepage layer, a landfill layer, a top face anti-seepage layer and a greening layer, the soil foundation layer, the bottom face anti-seepage layer, the landfill layer, the top face anti-seepage layer and the greening layer are sequentially arranged from bottom to top, the drainage ditch is arranged around the top face anti-seepage layer, the top face anti-seepage layer is high in the middle and low in the periphery, and a reverse slope anti-seepage layer is formed on the peripheral side of the top face anti-seepage layer. The counter-slope impermeable layer is fixedly connected with the drainage ditch, so that a water collecting area is formed between the counter-slope impermeable layer and the drainage ditch, one end of the drainage pipe is hermetically connected with the counter-slope impermeable layer, and the other end of the drainage pipe is fixedly connected with the drainage ditch, so that pipe orifices at two ends of the drainage pipe are respectively communicated with the water collecting area and a groove of the drainage ditch. According to the utility model, the problem of tearing or failure caused by the sinking phenomenon of a pile body in the prior art can be solved, and rainwater infiltration can be prevented.

Description

Technical Field

[0001] This utility model relates to the field of solid waste landfill technology, and in particular to a flexible landfill. Background Technology

[0002] Flexible landfills are waste disposal sites constructed using polymer materials, possessing a degree of flexibility and adaptability. They offer advantages such as low construction costs, mature technology, ease of operation, and suitability for large-scale solid waste disposal. Flexible landfills are primarily used for the disposal of industrial waste, solid waste, municipal solid waste, and other waste requiring secure landfill treatment. These wastes typically contain hazardous substances, and improper handling can cause serious harm to the environment and human health. Flexible landfills, with their excellent impermeability and terrain adaptability, provide an effective solution for the safe disposal of these wastes. Compared to traditional rigid landfills, flexible landfills offer advantages in cost, construction time, and site adaptability, thus gaining increasingly widespread application.

[0003] Flexible landfills generally include a seepage barrier system, a leachate drainage system, and a cover system. The seepage barrier system is a crucial component of a flexible landfill, used to isolate the landfill from the outside world, preventing leachate contamination of groundwater and surface water, and also preventing external water from entering the landfill area. The seepage barrier system is a system composed of various materials selected for constructing a leachate barrier on the bottom and surrounding slopes of the flexible landfill. At the final stage, a surface layer is also laid on top of the landfill.

[0004] However, the existing flexible landfill structure does not take into account the tear resistance of the seepage prevention system. Specifically, as the landfill slowly sinks over time, the top seepage prevention layer of the seepage prevention system will tear, allowing rainwater to easily seep into the landfill. Utility Model Content

[0005] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a flexible landfill that can solve the problem of tearing or failure caused by the subsidence of the landfill in the prior art, and can prevent rainwater infiltration.

[0006] This utility model embodiment provides a flexible landfill, which includes a drainage pipe, a drainage ditch, and a soil foundation layer, a bottom impermeable layer, a landfill layer, a top impermeable layer, and a greening layer arranged sequentially from bottom to top. The drainage ditch is arranged around the top impermeable layer, which is high in the middle and low around the edges. A reverse slope impermeable layer is formed on the periphery of the top impermeable layer. The reverse slope impermeable layer is fixedly connected to the drainage ditch so that the reverse slope impermeable layer and the drainage ditch together form a water collection area. One end of the drainage pipe is sealed to the reverse slope impermeable layer, and the other end is fixedly connected to the drainage ditch so that the two ends of the drainage pipe are respectively connected to the water collection area and the trench of the drainage ditch.

[0007] The flexible landfill according to the embodiments of this utility model has at least the following beneficial effects: Since the landfill material at the landfill layer will experience some subsidence due to its own weight and other external forces, by setting the top impermeable layer to be higher in the middle and lower on the periphery, and forming a reverse slope impermeable layer on its periphery, with the reverse slope impermeable layer fixedly connected to the drainage ditch, the top impermeable layer can maintain a certain tension when the landfill material at the landfill layer subsides. This allows the top impermeable layer to better adapt to the subsidence of the landfill material at the landfill layer, thereby preventing the top impermeable layer from tearing or failing due to the subsidence of the landfill material. Furthermore, rainwater can flow along the surface of the top impermeable layer to the water collection area and promptly flow into the drainage ditch through the drainage pipe, preventing rainwater from accumulating on the top impermeable layer and easily infiltrating into the interior of the landfill material at the landfill layer.

[0008] In some embodiments of this utility model, the top impermeable layer is inclined downward from the middle to the peripheral side, and the drainage pipe is inclined downward from the water collection area to the drainage ditch.

[0009] In some embodiments of this utility model, the drainage ditch is provided with a stepped portion, and the reverse slope seepage-proof layer extends upward from one end away from the top seepage-proof layer, and is arranged and fixedly connected to the stepped portion.

[0010] In some embodiments of this utility model, the end of the anti-seepage layer away from the top anti-seepage layer is embedded in the drainage ditch.

[0011] In some embodiments of this utility model, the flexible landfill further includes a peripheral impermeable layer, which is annular. The reverse slope impermeable layer extends upward from one end away from the top impermeable layer and is arranged in close contact with the sidewall of the drainage ditch. The upper part of the peripheral impermeable layer is arranged in close contact with the sidewall of the drainage ditch and is fixedly connected to the reverse slope impermeable layer. The lower part of the peripheral impermeable layer is fixedly connected to the bottom impermeable layer.

[0012] In some embodiments of this utility model, the slope of the anti-seepage layer is 5% to 10%.

[0013] In some embodiments of this utility model, the drain pipe is a flexible hose.

[0014] In some embodiments of this utility model, the drain pipe is a PE flexible hose.

[0015] In some embodiments of this utility model, the diameter of the drain pipe is 20cm to 50cm.

[0016] In some embodiments of this utility model, the length of the drain pipe is 2m.

[0017] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a flexible landfill according to an embodiment of the present invention;

[0019] Figure 2 This is a structural schematic diagram of a flexible landfill according to another embodiment of the present invention.

[0020] Attached reference numerals: 110, Green layer; 120, Fill layer; 130, Soil foundation layer; 200, Drainage ditch; 310, Top surface impermeable layer; 311, Inclined section; 312, Reverse slope impermeable layer; 313, Connecting section; 320, Bottom surface impermeable layer; 330, Peripheral impermeable layer; 400, Drainage pipe. Detailed Implementation

[0021] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0022] In the description of this utility model, it should be understood that features specified as "first" or "second" may explicitly or implicitly include one or more of those features. In the description of this utility model, unless otherwise stated, "several" means one or more, and "multiple" means two or more.

[0023] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0024] The following is for reference. Figure 1 and Figure 2 This invention describes a flexible landfill provided according to an embodiment of the present invention.

[0025] like Figure 1 and Figure 2 As shown, the flexible landfill according to this embodiment of the invention is suitable not only for landfills that cannot be anchored by earth trenches, have a basically stable pile body, and experience minimal settlement, but also for landfills that cannot be anchored by earth trenches and experience significant settlement, such as municipal solid waste. This flexible landfill can solve the problem of tearing or failure of the impermeable layer due to pile body settlement in the prior art, and can prevent rainwater infiltration.

[0026] The flexible landfill structure includes a drainage pipe 400, a drainage ditch 200, a soil foundation layer 130, a bottom impermeable layer 320, a landfill layer 120, a top impermeable layer 310, and a greening layer 110. The soil foundation layer 130, the bottom impermeable layer 320, the landfill layer 120, the top impermeable layer 310, and the greening layer 110 are arranged sequentially from bottom to top, and the drainage ditch 200 is arranged around the top impermeable layer 310.

[0027] Understandably, the soil foundation layer 130 can be compacted clay or concrete to ensure foundation stability and prevent uneven underground settlement from easily tearing the bottom and top impermeable layers 320 and 310. The landfill layer 120 can accommodate different types of solid waste. The green layer 110 is a vegetation layer, mainly used for ecological restoration, soil and water conservation, and landscaping after landfill closure. The green layer 110 can reduce rainwater infiltration, control erosion, and promote the ecological integration of the flexible landfill with the surrounding environment. The top and bottom impermeable layers 310 and 320 together constitute a flexible liner system, which mainly consists of a high-density polyethylene membrane (HDPE membrane). In some embodiments, both the top and bottom impermeable layers 310 and 320 are primarily composed of HDPE membrane, combined with geotextiles and bentonite pads to form a multi-layer impermeable structure.

[0028] The soil foundation layer 130 forms a landfill pit. A bottom impermeable layer 320 is attached to the upper surface of the soil foundation layer 130, with the bottom impermeable layer 320 having a lower center and higher periphery. The periphery of the bottom impermeable layer 320 is fixedly connected to the soil foundation layer 130; specifically, the edge portion of the bottom impermeable layer 320 can be embedded into the soil foundation layer 130. After the bottom impermeable layer 320 is installed, solid waste is placed on it to form a landfill layer 120. At this time, a drainage ditch 200 is arranged around the landfill layer 120, thus forming a ring structure when viewed vertically. The drainage ditch 200 and the bottom impermeable layer 320 together form the area for the landfill site. After the solid waste landfill work is completed, the top impermeable layer 310 is laid on top of the landfill layer 120, and the greening layer 110 is arranged on top of the top impermeable layer 310.

[0029] The function of the top impermeable layer 310 is to prevent rainwater from seeping into the landfill layer 120 and to prevent the diffusion of toxic and harmful gases. In this embodiment, the top impermeable layer 310 can adapt to certain landfill settlement conditions and prevent the top impermeable layer 310 from being torn due to landfill settlement within the landfill layer 120.

[0030] The top impermeable layer 310 is high in the middle and low around the edges. Specifically, the top impermeable layer 310 is sloped downwards from the middle to the periphery, that is, the top impermeable layer 310 has an arched structure, which allows rainwater to flow down the surface of the top impermeable layer 310 to the edge. A reverse slope impermeable layer 312 is formed around the periphery of the top impermeable layer 310. The reverse slope impermeable layer 312 is fixedly connected to and sealed with the drainage ditch 200, so that the reverse slope impermeable layer 312 and the drainage ditch 200 can jointly form a water collection area. At the same time, it can prevent rainwater from entering the landfill layer 120 through the gap between the reverse slope impermeable layer 312 and the drainage ditch 200.

[0031] like Figure 1 As shown, in one specific embodiment, the drainage ditch 200 has a stepped section located on the side of the drainage ditch 200 near the top impermeable layer 310. The end of the reverse slope impermeable layer 312 away from the top impermeable layer 310 extends upward and is arranged in close contact with the stepped section, and is fixedly connected to it. At this time, the connecting part 313 of the top impermeable layer 310 extends along the stepped section of the drainage ditch 200 and overlaps and fits on the stepped section. The end of the connecting part 313 away from the reverse slope impermeable layer 312 extends upward and is flush with the upper surface of the drainage ditch 200. This design can prevent rainwater from flowing into the landfill layer 120 through the gap between the reverse slope impermeable layer 312 and the drainage ditch 200. This embodiment is applicable to landfill disposal work for landfills that cannot be anchored by soil trench backfilling, have a basically stable pile body, and have little settlement.

[0032] In this embodiment, the top surface seepage-proof layer 310 includes an inclined portion 311, a reverse slope seepage-proof layer 312, and a connecting portion 313. The inclined portion 311, the reverse slope seepage-proof layer 312, and the connecting portion 313 are integrally formed. The inclined portion 311 is higher in the middle and lower on the periphery. The reverse slope seepage-proof layer 312 is located between the inclined portion 311 and the connecting portion 313. The connecting portion 313 is used for fixed connection with the drainage ditch 200. The inclined portion 311 and the reverse slope seepage-proof layer 312 form a certain angle α, which is an obtuse angle and can be 172°. The inclination angles of the inclined portion 311 and the reverse slope seepage-proof layer 312 can be set according to actual needs and are not specifically limited here. During the construction of the drainage ditch 200, the top surface seepage-proof layer 310 is embedded in the ditch wall of the drainage ditch 200, and finally, sealing and finishing treatment are performed.

[0033] like Figure 2 As shown, in another specific embodiment, the flexible landfill also includes a peripheral impermeable layer 330. The peripheral impermeable layer 330 is annular when viewed vertically and mainly comprises an HDPE membrane. The reverse slope impermeable layer 312 extends upwards from the end furthest from the top impermeable layer 310 and is arranged in close contact with the sidewall of the drainage ditch 200. The upper part of the peripheral impermeable layer 330 is arranged in close contact with the sidewall of the drainage ditch 200 and is fixedly connected to the reverse slope impermeable layer 312. The lower part of the peripheral impermeable layer 330 is fixedly connected to the bottom impermeable layer 320. It is understood that the peripheral impermeable layer 330 is fixedly connected to both the reverse slope impermeable layer 312 and the bottom impermeable layer 320, and they are mutually sealed. The fixing method is not limited to welding, bonding, etc. This embodiment is applicable to landfill disposal of materials such as municipal solid waste that cannot be anchored using earthen trenches and have large landfill settlement. After the drainage ditch 200 is excavated, the surrounding seepage-proof layer 330 is laid on the ditch wall and bottom of the drainage ditch 200 to ensure the flatness and tightness of the surrounding seepage-proof layer 330.

[0034] In another specific embodiment, the end of the reverse slope seepage barrier layer 312 away from the top seepage barrier layer 310 is embedded in the drainage ditch 200. It can be understood that the reverse slope seepage barrier layer 312 and the drainage ditch 200 are constructed as an integrated unit, with one end of the reverse slope seepage barrier layer 312 directly embedded into the ditch wall of the drainage ditch 200 to form an integrated structure that can prevent rainwater infiltration.

[0035] One end of the drainage pipe 400 is sealed to the anti-seepage layer 312. Specifically, the drainage pipe 400 is welded firmly to the periphery of the anti-seepage layer 312, and the other end of the drainage pipe 400 is fixedly connected to the drainage ditch 200, so that the two ends of the drainage pipe 400 are respectively connected to the water collection area and the trench of the drainage ditch 200. It can be understood that the installation of the drainage ditch 200 and the drainage pipe 400 can timely and smoothly discharge rainwater from the flexible landfill to the drainage ditch 200, preventing surface water from accumulating on the top anti-seepage layer 310 and being unable to drain, which would cause surface water to easily seep down from the connection between the top anti-seepage layer 310 and the drainage ditch 200 and enter the interior of the flexible landfill over time.

[0036] In some embodiments, the drain pipe 400 is inclined downwards from the water collection area toward the drainage ditch 200, so that water in the water collection area can flow along the drain pipe 400 into the ditch of the drainage ditch 200 due to gravity. Of course, it is not excluded that the drain pipe 400 is installed horizontally.

[0037] In addition, the flexible landfill also includes a leachate collection and drainage system and a groundwater collection and drainage system. The leachate collection and drainage system is used to collect leachate generated from landfill waste, preventing it from accumulating on the flexible liner system and causing the bottom impermeable layer 320 to crack or pollutants to seep into the ground. The groundwater collection and drainage system is used to intercept and drain groundwater at the bottom and around the flexible landfill, preventing it from seeping into the landfill layer 120 and coming into contact with solid waste, while also preventing the groundwater level from rising and supporting the bottom impermeable layer 320. The leachate collection and drainage system and the groundwater collection and drainage system are existing technologies, and this embodiment does not make any structural modifications. Therefore, those skilled in the art should understand their specific structure and working principle, and they will not be described in detail here.

[0038] In the flexible landfill provided in this embodiment of the utility model, since the pile body at the landfill layer 120 will sink to a certain extent due to its own weight and other external forces, by setting the top impermeable layer 310 to be high in the middle and low on the periphery, and forming a reverse slope impermeable layer 312 on the periphery of the top impermeable layer 310, and fixing the reverse slope impermeable layer 312 to the drainage ditch 200, the connection between the top impermeable layer 310 and the drainage ditch 200 is provided with a reverse slope impermeable layer 312, so that the top impermeable layer 310 can maintain a certain tension when the pile body at the landfill layer 120 sinks, so that the top impermeable layer 310 can better adapt to the sinking of the pile body at the landfill layer 120, thereby avoiding the top impermeable layer 310 from tearing or failing due to the sinking of the pile body. Moreover, rainwater can flow along the surface of the top impermeable layer 310 to the water collection area, and then flow into the trench of the drainage ditch 200 in a timely manner through the drainage pipe 400, preventing rainwater from accumulating on the top impermeable layer 310 and easily seeping into the interior of the landfill layer 120.

[0039] In some embodiments, the slope of the reverse slope waterproofing layer 312 is 5% to 10%. It is understood that the slope is the ratio of the height difference to the horizontal distance. The slope of the reverse slope waterproofing layer 312 can be set to 5%, 8%, or 10%. If settlement coefficient data is available, the slope of the reverse slope waterproofing layer 312 can be set with reference to the settlement coefficient.

[0040] In some embodiments, the drain pipe 400 is a flexible hose. Specifically, the drain pipe 400 is a PE (polyethylene) flexible hose. Of course, it is not excluded that in other embodiments, materials with corrosion resistance, wear resistance, and high strength, such as HDPE, may also be used to manufacture the drain pipe 400.

[0041] Furthermore, the diameter of the drainage pipe 400 is 20cm to 50cm. The length of the drainage pipe 400 is 2m. It is understood that the actual diameter, length, and arrangement of the drainage pipe 400 are determined based on the actual conditions and design requirements of the flexible landfill to ensure smooth drainage. The number of drainage pipes 400 is not limited to one. When multiple drainage pipes 400 are installed, they can be evenly arranged around the perimeter of the top impermeable layer 310.

[0042] In this embodiment of the flexible landfill, the top impermeable layer 310 is a key component ensuring the stable operation of the flexible landfill and preventing environmental pollution, guaranteeing the stability and durability of the landfill's impermeability system. The periphery of the top impermeable layer 310 employs a reverse-slope impermeable layer 312 structure, allowing it to better adapt to the subsidence of the landfill body at the landfill layer 120. It is understood that the landfill body will experience some subsidence due to its own weight and other external forces during the landfilling process. This embodiment, by employing a reverse-slope design, ensures that the top impermeable layer 310 maintains a certain tension during landfill subsidence, thereby preventing the top impermeable layer 310 from tearing or failing due to landfill subsidence.

[0043] Furthermore, the reverse slope design can improve the overall stability of the flexible landfill. Understandably, since there is a certain angle between the top impermeable layer 310 and the horizontal plane, this design can increase the friction between the top impermeable layer 310 and the pile body, allowing the top impermeable layer 310 to adhere more firmly to the pile body and preventing damage to the top impermeable layer 310 due to the sliding or collapse of the pile body.

[0044] In this embodiment of the flexible landfill, the top impermeable layer 310 is integrated with the drainage ditch 200 through the reverse slope impermeable layer 312. The reverse slope impermeable layer 312 is directly embedded into the wall of the drainage ditch 200, thus forming an effective waterproof barrier, significantly improving the seepage prevention effect. This ensures that rainwater flows sequentially through the top impermeable layer 310 and the reverse slope impermeable layer 312, is effectively guided to the catchment area, and is discharged into the trench of the drainage ditch 200 through the drainage pipe 400, significantly reducing the possibility of rainwater entering the landfill layer 120. Furthermore, the integrated construction method ensures a tight connection between the top impermeable layer 310 and the drainage ditch 200 through the reverse slope impermeable layer 312, enhancing the overall stability of the flexible landfill.

[0045] A drainage pipe 400 is installed between the catchment area and the drainage ditch 200 to provide an effective drainage channel. When rainfall occurs, rainwater will flow along the top impermeable layer 310 and the reverse slope impermeable layer 312 to the drainage pipe 400, and will be discharged into the drainage ditch 200 under the guidance of the drainage pipe 400. Subsequently, the water in the drainage ditch 200 will be discharged to the outside of the flexible landfill through the existing drainage system to prevent rainwater from accumulating and infiltrating into the landfill 120.

[0046] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0047] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A flexible landfill, characterized in that, The system includes drainage pipes, drainage ditches, and, from bottom to top, a soil foundation layer, a bottom impermeable layer, a fill layer, a top impermeable layer, and a greening layer. The drainage ditch is arranged around the top impermeable layer, which is higher in the middle and lower around the edges. A reverse slope impermeable layer is formed on the periphery of the top impermeable layer. The reverse slope impermeable layer is fixedly connected to the drainage ditch so that the reverse slope impermeable layer and the drainage ditch together form a water collection area. One end of the drainage pipe is sealed to the reverse slope impermeable layer, and the other end is fixedly connected to the drainage ditch so that the two ends of the drainage pipe are respectively connected to the water collection area and the trench of the drainage ditch.

2. The flexible landfill according to claim 1, characterized in that, The top impermeable layer is inclined downward from the middle to the periphery, and the drainage pipe is inclined downward from the water collection area to the drainage ditch.

3. The flexible landfill according to claim 1, characterized in that, The drainage ditch is provided with a stepped section, and the reverse slope seepage prevention layer extends upward from the end away from the top seepage prevention layer, and is arranged and fixedly connected to the stepped section.

4. The flexible landfill according to claim 1, characterized in that, The end of the anti-seepage layer away from the top anti-seepage layer is embedded in the drainage ditch.

5. The flexible landfill according to claim 1, characterized in that, It also includes a peripheral seepage barrier layer, which is annular. The reverse slope seepage barrier layer extends upward from one end away from the top surface seepage barrier layer and is arranged in close contact with the side wall of the drainage ditch. The upper part of the peripheral seepage barrier layer is arranged in close contact with the side wall of the drainage ditch and is fixedly connected to the reverse slope seepage barrier layer. The lower part of the peripheral seepage barrier layer is fixedly connected to the bottom surface seepage barrier layer.

6. The flexible landfill according to any one of claims 1 to 5, characterized in that, The slope of the anti-seepage layer is 5% to 10%.

7. The flexible landfill according to claim 1, characterized in that, The drain pipe is a flexible hose.

8. The flexible landfill according to claim 7, characterized in that, The drain pipe is a PE flexible hose.

9. The flexible landfill according to claim 7 or 8, characterized in that, The diameter of the drain pipe is 20cm to 50cm.

10. The flexible landfill according to claim 9, characterized in that, The length of the drain pipe is 2m.

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