A landfill leachate drainage system

Abstract

The present invention discloses a leachate drainage system for a landfill, which belongs to the technical field of leachate drainage in landfills and includes: a partition dam arranged inside the landfill to divide the landfill into multiple landfill areas; a main drainage ditch arranged at the bottom of the landfill, running through the landfill areas and the partition dam, with one end of the main drainage ditch higher than the other end; secondary drainage ditches arranged on both sides of the main drainage ditch and at the toe of the slope of the landfill slope, with one end of the secondary drainage ditch higher than the other end; multiple main drainage pipes arranged at the bottom of the main drainage ditch; secondary drainage pipes arranged at the bottom of the secondary drainage ditches; a collection well arranged at the toe of the slope of the other end of the landfill near the main drainage ditch and connected to the other ends of the main drainage pipes and the secondary drainage pipes; a drainage pipe with one end arranged inside the collection well; this drainage system can achieve zonal drainage of landfill leachate, reduce the drainage pressure of each drainage pipe, and has secondary drainage pipes, which can further ensure the effective drainage of leachate.

Description

Technical Field

[0001] The present invention belongs to the technical field of landfill leachate drainage, and more specifically, relates to a landfill leachate drainage system. Background Art

[0002] As the final disposal site for solid waste, the landfill solves the problem of the final disposal of urban solid waste. At present, most of the domestic landfill leachate drainage systems are designed with main blind ditches and branch blind ditches for joint drainage. A HDPE perforated pipe is arranged in both the main blind ditch and the branch blind ditch. The HDPE perforated pipe in the branch blind ditch is connected to the HDPE perforated pipe in the main blind ditch. The leachate is drained through the branch blind ditch and collected in the main blind ditch, and finally drained into the regulating pond. The operation life of the landfill is generally more than 10 years. During the long-term operation, the leachate reacts chemically with CaCO3 in the drainage pebbles or crushed stones to generate a cement-like cementing substance, causing scale formation in the drainage pipes. Coupled with the continuous deposition of fine particles in the leachate, it is very easy for the main blind ditch in the leachate drainage system to be partially blocked or completely blocked. Once the main blind ditch for leachate drainage is blocked, the branch blind ditch and the main blind ditch above the blockage point will lose the leachate collection well drainage function, and the location area of the pipeline blockage is difficult to determine, and the difficulty of dredging and repairing is large, resulting in the leachate in the garbage heap body cannot be drained quickly and effectively, and is long-term accumulated in the heap body, causing the water level line to be too high, affecting the safety and stability of the garbage heap body. Summary of the Invention

[0003] The purpose of the present invention is to provide a landfill leachate drainage system to address the deficiencies in the prior art. The system can achieve zoned drainage of landfill leachate, reduce the drainage pressure and blockage probability of each drainage pipe, and has a secondary drainage pipe to further ensure the effective drainage of leachate.

[0004] To achieve the above object, the present invention provides a landfill leachate drainage system, comprising:

[0005] Partition dams, arranged inside the landfill, dividing the landfill into multiple landfill areas;

[0006] Main drainage ditches, arranged at the bottom of the landfill, passing through the landfill areas and the partition dams, with one end of the main drainage ditch higher than the other end;

[0007] Secondary drainage ditches, arranged on both sides of the main drainage ditch, at the toe of the slope of the landfill slope, with one end of the secondary drainage ditch higher than the other end;

[0008] Multiple main drainage pipes, arranged at the bottom of the main drainage ditch;

[0009] Secondary drainage pipes, arranged at the bottom of the secondary drainage ditch;

[0010] A collection well is arranged at the foot of the slope of the landfill on the other end close to the main drainage ditch, and is communicated with the other ends of the main drainage pipe and the secondary drainage pipe;

[0011] A drainage pipe has one end arranged in the collection well.

[0012] Optionally, first guide slopes and second guide slopes are respectively arranged on both sides of the main drainage ditch and the secondary drainage ditch. One end of the first guide slope close to the main drainage ditch is lower than the end far from the main drainage ditch, and one end of the second guide slope close to the secondary drainage ditch is lower than the end far from the secondary drainage ditch.

[0013] Optionally, the cross-sectional shape of the partition dam is trapezoidal, and the outer side of the partition dam is coated with an anti-seepage layer, and the anti-seepage layer is connected to the anti-seepage layer at the bottom of the landfill.

[0014] Optionally, a first cushion layer and a second cushion layer are respectively arranged at the bottoms of the main drainage ditch and the secondary drainage ditch. The main drainage pipe and the secondary drainage pipe are respectively arranged on the upper sides of the first cushion layer and the second cushion layer. The outer sides of the main drainage pipe and the secondary drainage pipe in the main drainage ditch and the secondary drainage ditch are filled with a first filler, and the outside of the first filler is wrapped with a first filter layer.

[0015] Optionally, a third cushion layer is arranged at the bottom of the collection well. The collection well is filled with a second filler, and the outside of the second filler is wrapped with a second filter layer.

[0016] Optionally, the drainage pipe includes a horizontal part and an inclined part. One end of the horizontal part is connected to the inclined part to form a broken line shape. The horizontal part is arranged on the upper side of the third cushion layer at the bottom of the collection well. A plurality of first pipe holes are formed in the pipe wall of the horizontal part. A blocking baffle is arranged at the other end of the horizontal part. The inclined part is arranged on the slope close to the collection well. A first blind ditch is arranged on the slope close to the collection well. The inclined part is arranged in the first blind ditch and filled with clay or concrete.

[0017] Optionally, a flushing pipe is further included. The flushing pipe is communicated with the one ends of the main drainage pipe and the secondary drainage pipe. The flushing pipe is arranged on the slope on the side of the landfill far from the collection well. A second blind ditch is arranged on the slope on the side of the landfill far from the collection well. The flushing pipe is arranged in the second blind ditch and filled with clay or concrete.

[0018] Optionally, a plurality of landfill areas are arranged along the axis direction of the main drainage ditch.

[0019] Optionally, the number of the main drain pipes is equal to the number of the landfill areas. Multiple main drain pipes are arranged side by side. A plurality of second pipe holes are formed in the pipe walls of different main drain pipes in different landfill areas respectively. A plurality of third pipe holes are formed in the pipe wall of the secondary drain pipe located in the landfill area.

[0020] Optionally, a main gate valve is provided on the main drain pipe in the landfill area where the second pipe hole is located. The main gate valve is arranged inside the main drain pipe near the other end of the main drain ditch. A secondary gate valve is provided on the secondary drain pipe in the landfill area where the third pipe hole is located. The secondary gate valve is arranged inside the secondary drain pipe near the other end of the secondary drain ditch.

[0021] The present invention provides a landfill leachate drainage system, and its beneficial effects are as follows:

[0022] 1. The drainage system can achieve the zonal drainage of landfill leachate, reduce the drainage pressure and the possibility of blockage of each drain pipe, and has a secondary drain pipe, which can further ensure the effective drainage of leachate;

[0023] 2. The drainage system opens second pipe holes in different landfill areas through different main drain pipes, and main gate valves are arranged at different positions of different main drain pipes, so that the drainage in each landfill area can operate independently, that is, it can ensure the drainage effect and is convenient for judging the blockage situation in different main drain pipes;

[0024] 3. The drainage system has a flushing pipe, which can realize the flushing of each main drain pipe and secondary drain pipe. On the one hand, it is beneficial to keep the pipeline unobstructed. On the other hand, it can judge the blocked area by combining the flushing situation with the drainage situation of each main drain pipe and secondary drain pipe, which is convenient for dealing with blockage.

[0025] Other features and advantages of the present invention will be described in detail in the following specific implementation manners. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] By describing the exemplary embodiments of the present invention in more detail in conjunction with the drawings, the above and other objects, features and advantages of the present invention will become more obvious. Among them, in the exemplary embodiments of the present invention, the same reference numerals generally represent the same components.

[0027] Figure 1 FIG. shows a schematic plan view of a landfill leachate drainage system according to an embodiment of the present invention.

[0028] Figure 2 FIG. shows a schematic structural view of a partition dam of a landfill leachate drainage system according to an embodiment of the present invention.

[0029] Figure 3Shows a schematic structural diagram of the main drainage ditch of a landfill leachate drainage system according to an embodiment of the present invention.

[0030] Figure 4 Shows a schematic structural diagram of the secondary drainage ditch of a landfill leachate drainage system according to an embodiment of the present invention.

[0031] Figure 5 Shows a schematic plan view of the collection well of a landfill leachate drainage system according to an embodiment of the present invention.

[0032] Figure 6 Shows a schematic longitudinal sectional structure diagram of the collection well of a landfill leachate drainage system according to an embodiment of the present invention.

[0033] Figure 7 Shows a schematic sectional structure diagram of the collection well of a landfill leachate drainage system according to an embodiment of the present invention.

[0034] Figure 8 Shows a schematic sectional structure diagram of the pumping pipe of a landfill leachate drainage system according to an embodiment of the present invention.

[0035] Figure 9 Shows a schematic longitudinal sectional structure diagram of the flushing pipe of a landfill leachate drainage system according to an embodiment of the present invention.

[0036] Figure 10 Shows a schematic sectional structure diagram of the flushing pipe of a landfill leachate drainage system according to an embodiment of the present invention.

[0037] Explanation of reference numerals:

[0038] 1. Partition dam; 2. Landfill; 3. Landfill area; 4. Main drainage ditch; 5. Secondary drainage ditch; 6. Main drainage pipe; 7. Secondary drainage pipe; 8. Collection well; 9. Pumping pipe; 10. First guiding slope; 11. Second guiding slope; 12. Impervious layer; 13. First cushion layer; 14. Second cushion layer; 15. First filler; 16. First filter layer; 17. Third cushion layer; 18. Second filler; 19. Second filter layer; 20. Horizontal part; 21. Inclined part; 22. Sealing baffle; 23. Flushing pipe; 24. Main gate valve; 25. First landfill area; 26. Second landfill area; 27. Third landfill area; 28. First partition dam; 29. Second partition dam; 30. First main drainage pipe; 31. Second main drainage pipe; 32. Third main drainage pipe; 33. First blind ditch; 34. Second blind ditch. Detailed implementation manners

[0039] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0040] The present invention provides a landfill leachate drainage system, comprising:

[0041] Partition dams, which are arranged inside the landfill and divide the landfill into multiple landfill areas;

[0042] Main drainage ditches, which are arranged at the bottom of the landfill, penetrate the landfill areas and the partition dams, and one end of the main drainage ditch is higher than the other end;

[0043] Secondary drainage ditches, which are arranged on both sides of the main drainage ditch and at the toe of the slope of the landfill side slope, and one end of the secondary drainage ditch is higher than the other end;

[0044] Multiple main drainage pipes, which are arranged at the bottom of the main drainage ditch;

[0045] Secondary drainage pipes, which are arranged at the bottom of the secondary drainage ditch;

[0046] Collection wells, which are arranged at the toe of the slope of the other end of the landfill close to the main drainage ditch and are connected to the other ends of the main drainage pipes and the secondary drainage pipes;

[0047] A pumping drainage pipe, one end of which is arranged in the collection well.

[0048] Specifically, the partition dams divide the landfill into multiple landfill areas, which facilitates the zoned drainage of the landfill, reduces the drainage pressure in each area, improves the drainage effect, and facilitates the judgment of the clogging position to achieve zoned treatment of the clogging; the main drainage ditches and the secondary drainage ditches are provided to effectively drain the leachate inside the landfill area and at the edge of the landfill area respectively. The leachate enters the main drainage pipes and the secondary drainage pipes, and the main drainage pipes and the secondary drainage pipes drain the leachate into the collection well, and then it can be pumped out by the pumping drainage pipe; the secondary drainage ditch can drain the leachate in time when the main drainage ditch is clogged and fails, ensuring the reliability of the drainage system.

[0049] Optionally, first guide slopes and second guide slopes are respectively arranged on both sides of the main drainage ditch and the secondary drainage ditch. One end of the first guide slope close to the main drainage ditch is lower than the end far from the main drainage ditch, and one end of the second guide slope close to the secondary drainage ditch is lower than the end far from the secondary drainage ditch. The slopes of the first guide slope and the second guide slope are not less than 2%.

[0050] Specifically, the main drainage ditch is arranged at the mid-axis position in the length direction of the landfill. The main drainage ditch is filled with filler, and the outside is wrapped with filter material, so that the cross-sectional shape of the main drainage ditch is hexagonal. The depth of the main drainage ditch is 800 - 1000 mm, and the bottom width range of the main drainage ditch is 2 - 4 m; the secondary drainage ditch is filled with filler, and the outside is wrapped with filter material, so that the cross-sectional shape of the secondary drainage ditch is hexagonal. The depth of the secondary drainage ditch is 800 - 1000 mm, and the bottom width of the secondary drainage ditch is 1000 - 1200 mm.

[0051] The filler is pebbles or gravel with a particle size of 20 - 60 mm, and the CaCO3 content in the filler does not exceed 5%.

[0052] The filter material is a geotextile filter with a specification of not less than 200 g / m2.

[0053] Optionally, the cross-sectional shape of the partition dam is trapezoidal, and the outside of the partition dam is coated with an anti-seepage layer, which is connected to the anti-seepage layer at the bottom of the landfill.

[0054] Specifically, the partition dam is made of clay, with a dam height of 2 - 4 m, an inner and outer slope ratio of 1:1 - 1:2, and a dam top width of 2 - 4 m. Anti-seepage layers are provided on the slopes and the top of the partition dam and are connected to the anti-seepage layer at the bottom of the landfill to play an anti-seepage role, extend the life of the partition dam, and avoid secondary pollution.

[0055] Optionally, a first cushion layer and a second cushion layer are respectively arranged at the bottoms of the main drainage ditch and the secondary drainage ditch. The main drainage pipe and the secondary drainage pipe are respectively arranged on the upper sides of the first cushion layer and the second cushion layer. The outside of the main drainage pipe and the secondary drainage pipe in the main drainage ditch and the secondary drainage ditch is filled with a first filler, and the outside of the first filler is wrapped with a first filter layer.

[0056] Specifically, the thickness of the first cushion layer and the second cushion layer is 100 - 200 mm, and the material is medium-coarse sand or fine-grained gravel; the filter material of the first filter layer is a geotextile filter with a specification of not less than 200 g / m 2 ; the first filler is pebbles or gravel with a particle size of 20 - 60 mm, and the CaCO3 content in the first filler does not exceed 5%.

[0057] Optionally, a third cushion layer is arranged at the bottom of the collection well. The collection well is filled with a second filler, and the outside of the second filler is wrapped with a second filter layer.

[0058] Specifically, the collection well is arranged at the ends of the main drainage ditch and the secondary drainage ditch, which is also the lowest point of the landfill area. Its depth is 1 - 1.5 m, length is 4 - 8 m, and width is 10 m. The main drainage pipe in the main drainage ditch enters the collection well with a length of 500 - 1000 mm, and the secondary drainage pipe in the secondary drainage ditch enters the collection well with a length of 500 - 1000 mm. A drainage pipe is arranged near the slope position of the collection well. The inside of the collection well is filled with gravel or pebbles, and the outside of the pool body is wrapped with filter materials. The third cushion layer is a sand cushion layer with a thickness of 100 - 200 mm.

[0059] Optionally, the drainage pipe includes a horizontal part and an inclined part. One end of the horizontal part is connected to the inclined part to form a broken line shape. The horizontal part is arranged on the upper side of the third cushion layer at the bottom of the collection well. There are multiple first pipe holes on the pipe wall of the horizontal part. A sealing baffle is arranged at the other end of the horizontal part. The inclined part is arranged on the slope near the collection well. A first blind ditch is arranged on the slope near the collection well, and the inclined part is arranged in the first blind ditch and filled with clay or concrete.

[0060] Specifically, the horizontal part of the drainage pipe in the collection well is closely arranged against the sand cushion layer. The pipe length is 1500 - 3000 mm. The drainage pipe is a HDPE pipe with a diameter preferably of 600 - 1000 mm. Among them, the inclined part is a solid HDPE pipe, and the solid HDPE pipe is laid at the bottom of the first blind ditch. The first blind ditch is an inverted trapezoidal structure with a ditch depth of 1000 - 1200 mm, a bottom width of 1000 - 1200 mm, a top width of more than 2000 mm, and the inside of the ditch is backfilled and compacted with clay or concrete is poured. The horizontal part is a HDPE perforated pipe, and the HDPE perforated pipe and the solid HDPE pipe are connected by welding.

[0061] Optionally, it further includes a flushing pipe. The flushing pipe is connected to one end of the main drainage pipe and the secondary drainage pipe. The flushing pipe is arranged on the slope on the side of the landfill away from the collection well. A second blind ditch is arranged on the slope on the side of the landfill away from the collection well, and the flushing pipe is arranged in the second blind ditch and filled with clay or concrete.

[0062] Specifically, the flushing pipe is a solid HDPE pipe, and its diameter is the same as that of the main drainage pipe and the secondary drainage pipe it is connected to. The flushing pipe and the main drainage pipe and the secondary drainage pipe are connected by welding. The second blind ditch is an inverted trapezoidal structure with a bottom width of 500 - 600 mm, a height of 500 - 600 mm, and a top width of 1200 - 1500 mm. The outside of the flushing pipe is backfilled and compacted with clay or concrete is poured.

[0063] Optionally, multiple landfill areas are arranged along the axial direction of the main drainage ditch.

[0064] Specifically, multiple landfill areas are arranged along the axis direction of the main drainage ditch, thus forming a landfill leachate drainage unit; in one example, there is one such landfill leachate drainage unit in the landfill, and the landfill is separated into a series of multiple landfill areas by partition dams, and the main drainage ditches below the multiple landfill areas are arranged from low to high; in other examples, there are multiple such landfill leachate drainage units in the landfill, and the landfill is separated into multiple columns of landfill areas by partition dams, each column has multiple landfill areas, and the main drainage ditches below each column of landfill areas are arranged from low to high.

[0065] Optionally, the number of main drainage pipes is equal to the number of landfill areas. Multiple main drainage pipes are arranged side by side. Multiple second pipe holes are opened on the pipe walls of different main drainage pipes in different landfill areas, and multiple third pipe holes are opened on the pipe walls of the secondary drainage pipes in the landfill areas.

[0066] Specifically, each main drainage ditch is responsible for draining the leachate in one landfill area. The leachate flows into the main drainage pipe through the second pipe holes and is drained to the collection well through the main drainage pipe, realizing zoned drainage and improving the drainage effect; the distance between adjacent main drainage pipes is 600 - 900 mm, all made of HDPE material, and the diameter can be 315 mm, 355 mm or 400 mm. The diameters of multiple main drainage pipes are kept the same; the secondary drainage pipe can replace the main drainage pipe to complete the drainage work of the leachate in the landfill area it is responsible for when the drainage of a certain main drainage pipe fails, and the working principle is the same as that of the main drainage pipe.

[0067] Optionally, a main gate valve is provided on the main drainage pipe in the landfill area where the second pipe hole is located. The main gate valve is arranged inside the main drainage pipe near the other end of the main drainage ditch. A secondary gate valve is provided on the secondary drainage pipe in the landfill area where the third pipe hole is located. The secondary gate valve is arranged inside the secondary drainage pipe near the other end of the secondary drainage ditch.

[0068] Specifically, by separately opening the main gate valves on each main drainage pipe, the separate operation of the drainage of each landfill area can be realized, and combined with the flushing of the flushing pipe, the clogging condition of the landfill area can be judged according to the flow rate in different main drainage pipes; the working principle of the secondary drainage pipe is the same as that of the main drainage pipe. The selective opening and closing of the secondary gate valve combined with the flushing of the flushing pipe can also assist in judging the clogging condition of different landfill areas according to the flow rate.

[0069] Embodiment

[0070] Such as Figures 1 to 10 , the present invention provides a landfill leachate drainage system, including:

[0071] Partition dam 1, arranged inside the landfill 2, separating the landfill 2 into multiple landfill areas 3;

[0072] The main drainage ditch 4 is arranged at the bottom of the landfill 2, runs through the landfill area 3 and the partition dam 1, and one end of the main drainage ditch 4 is higher than the other end;

[0073] The secondary drainage ditches 5 are arranged on both sides of the main drainage ditch 4 and at the toe of the slope of the side slope of the landfill 2. One end of the secondary drainage ditch 5 is higher than the other end;

[0074] Multiple main drainage pipes 6 are arranged at the bottom of the main drainage ditch 4;

[0075] The secondary drainage pipes 7 are arranged at the bottom of the secondary drainage ditches 5;

[0076] The collection well 8 is arranged at the toe of the slope of the side slope of the landfill 2 near the other end of the main drainage ditch 4 and is connected to the other ends of the main drainage pipe 6 and the secondary drainage pipe 7;

[0077] One end of the pumping drainage pipe 9 is arranged in the collection well 8.

[0078] In this embodiment, first guide slopes 10 and second guide slopes 11 are respectively arranged on both sides of the main drainage ditch 4 and the secondary drainage ditches 5. One end of the first guide slope 10 close to the main drainage ditch 4 is lower than the end far from the main drainage ditch 4, and one end of the second guide slope 11 close to the secondary drainage ditch 5 is lower than the end far from the secondary drainage ditch 5. The slopes of the first guide slope 10 and the second guide slope 11 are not less than 2%.

[0079] In this embodiment, the cross-sectional shape of the partition dam 1 is trapezoidal, and the outer side of the partition dam 1 is coated with an anti-seepage layer 12, and the anti-seepage layer 12 is connected to the anti-seepage layer 12 at the bottom of the landfill 2.

[0080] In this embodiment, a first cushion layer 13 and a second cushion layer 14 are respectively arranged at the bottoms of the main drainage ditch 4 and the secondary drainage ditches 5. The main drainage pipes 6 and the secondary drainage pipes 7 are respectively arranged on the upper sides of the first cushion layer 13 and the second cushion layer 14. The outer sides of the main drainage pipes 6 and the secondary drainage pipes 7 in the main drainage ditch 4 and the secondary drainage ditches 5 are filled with a first filler 15, and the outside of the first filler 15 is wrapped with a first filter layer 16.

[0081] In this embodiment, a third cushion layer 17 is arranged at the bottom of the collection well 8, the collection well 8 is filled with a second filler 18, and the outside of the second filler 18 is wrapped with a second filter layer 19.

[0082] In this embodiment, the pumping drainage pipe 9 includes a horizontal part 20 and an inclined part 21. One end of the horizontal part 20 is connected to the inclined part 21 to form a broken line shape. The horizontal part 20 is arranged on the upper side of the third cushion layer 17 at the bottom of the collection well 8. A plurality of first pipe holes are formed in the pipe wall of the horizontal part 20. A blocking baffle 22 is arranged at the other end of the horizontal part 20. The inclined part 21 is arranged on the side slope near the collection well 8. A first blind ditch 33 is arranged on the side slope near the collection well 8. The inclined part 21 is arranged in the first blind ditch 33 and filled with clay or concrete.

[0083] In this embodiment, it further includes a flushing pipe 23. The flushing pipe 23 is communicated with one ends of the main drainage pipe 6 and the secondary drainage pipe 7. The flushing pipe 23 is arranged on the slope on one side of the landfill 2 away from the collection well 8. A second blind ditch 34 is arranged on the slope on the side away from the collection well 8. The flushing pipe 23 is arranged in the second blind ditch 34 and filled with clay or concrete.

[0084] In this embodiment, a plurality of landfill areas 3 are arranged along the axis direction of the main drainage ditch 4.

[0085] In this embodiment, the number of the main drainage pipes 6 is equal to the number of the landfill areas 3. A plurality of main drainage pipes 6 are arranged side by side. A plurality of second pipe holes are formed in the pipe walls of different main drainage pipes 6 in different landfill areas 3 respectively. A plurality of third pipe holes are formed in the pipe wall of the secondary drainage pipe 7 in the landfill area 3.

[0086] In this embodiment, a main gate valve 24 is arranged on the main drainage pipe 6 in the landfill area 3 where the second pipe holes are located. The main gate valve 24 is arranged inside the main drainage pipe 6 near the other end of the main drainage ditch 4. A secondary gate valve is arranged on the secondary drainage pipe 7 in the landfill area 3 where the third pipe holes are located. The secondary gate valve is arranged inside the secondary drainage pipe 7 near the other end of the secondary drainage ditch 5.

[0087] In this embodiment, 2 secondary drainage pipes 7 are provided.

[0088] In this embodiment, there are 3 landfill areas 3. The 3 landfill areas 3 are arranged along the axis direction of the main drainage ditch 4. In the direction from low to high of the main drainage ditch 4, they are the first landfill area 25, the second landfill area 26 and the third landfill area 27 in sequence. The partition dam between the first landfill area 25 and the second landfill area 26 is the first partition dam 28, and the partition dam between the second landfill area 26 and the third landfill area 27 is the second partition dam 29.

[0089] In this embodiment, 3 main drainage pipes 6 are provided, which are the first main drainage pipe 30, the second main drainage pipe 31 and the third main drainage pipe 32 respectively. A plurality of second pipe holes are formed in the first main drainage pipe 30 in the first landfill area 25, a plurality of second pipe holes are formed in the second main drainage pipe 31 in the second landfill area 26, and a plurality of second pipe holes are formed in the third main drainage pipe 32 in the third landfill area 27.

[0090] In this embodiment, a first main gate valve is arranged at one end of the first main drainage pipe 30 in the first landfill area 25 close to the collection well 8, a second main gate valve is arranged at one end of the second main drainage pipe 31 in the second landfill area 26 close to the first partition dam 28, and a third main gate valve is arranged at one end of the third main drainage pipe 32 in the third landfill area 27 close to the second partition dam 29.

[0091] In other embodiments, the first main drain pipe 30 may not be provided with a first main gate valve. The leachate in the first landfill area 25 can enter the first main drain pipe 30 through the second pipe hole and then directly flow into the collection well 8.

[0092] In summary, when the landfill leachate drainage system provided by the present invention is in use, after the landfill is completed, landfill operations are first carried out in the first landfill area 25. At this stage, there is no landfill in the second landfill area 26 and the third landfill area 27, and the second main gate valve and the third main gate valve are closed, so that rainwater or other liquids in the second landfill area 26 and the third landfill area 27 cannot flow into the collection well 8, effectively achieving diversion. At this time, the second main drain pipe 31 and the third main drain pipe 32 can pump out the leachate in the second landfill area 26 and the third landfill area 27 through a water pump. The collection well 8 only collects the leachate discharged from the first main drain pipe 30, which is convenient for judging the blockage situation in the first main drain pipe 30 and the first landfill area 25 through the pumping flow rate. The leachate in the first landfill area 25 enters the first main drain pipe 30 through the second pipe hole on the first main drain pipe 30. Opening the first main gate valve can drain the leachate to the collection well 8. At the other end of the pumping pipe 9, the leachate in the collection well 8 can be pumped out through a water pump, and the blockage in the first main drain pipe 30 and the first landfill area 25 can be preliminarily judged through the pumping volume.

[0093] When the first landfill area 25 reaches the intermediate operation elevation, landfill operations are carried out in the second landfill area 26, the first main gate valve is kept open, the second main gate valve is opened, and the third main gate valve remains closed; at this time, the first landfill area 25 and the second landfill area 26 work simultaneously. The leachate in the first landfill area 25 and the second landfill area 26 enters the first main drain pipe 30 and the second main drain pipe 31 through the second pipe holes on the first main drain pipe 30 and the second main drain pipe 31 respectively, and then flows into the collection well 8. There is no landfill in the third landfill area 27, and rainwater or other liquids in the third landfill area 27 cannot flow into the collection well 8, effectively achieving diversion. At this time, the third main drain pipe 32 can pump out the leachate in the third landfill area 27 through a water pump. The collection well 8 collects the leachate discharged from the first main drain pipe 30 and the second main drain pipe 31, which is convenient for judging the blockage situation of the first main drain pipe 30 and the second main drain pipe 31, and the first landfill area 25 and the second landfill area 26 through the pumping flow rate; of course, when judging, one of the first main gate valve or the second main gate valve can be selectively closed, which is more conducive to judging the blockage position.

[0094] When the second landfill area 26 also reaches the intermediate operation elevation, landfill operations are carried out in the third landfill area 27. Keep the first main gate valve and the second main gate valve open, and open the third main gate valve. At this time, the three landfill areas 3 work simultaneously, and the three main drainage pipes 6 respectively drain the leachate in the three landfill areas 3 into the collection well 8, and then drain it through the pumping pipe 9, realizing zoned drainage and improving the drainage effect of the landfill leachate.

[0095] To ensure the smoothness of the three main drainage pipes, during the landfill operation process, the main drainage pipes 6 and the secondary drainage pipes 7 are regularly flushed through the flushing pipe 23 to prevent the main drainage pipes 6 and the secondary drainage pipes 7 from being blocked by the cement-like cementitious substances generated by the reaction of the leachate with CaCO3 in the pebbles. At the same time, by separately opening one of the three main gate valves, according to the flow rate during the regular flushing of the three main drainage pipes 6 and the two secondary drainage pipes 7, it is judged whether there is a blockage problem in the first landfill area 25, the second landfill area 26 and the third landfill area 27, so as to carry out repair and dredging in time.

[0096] The embodiments of the present invention have been described above. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A landfill leachate drainage system, characterized in that, Including: A partition dam is arranged inside the landfill and divides the landfill into multiple landfill areas; A main drainage ditch is arranged at the bottom of the landfill, runs through the landfill areas and the partition dam, and one end of the main drainage ditch is higher than the other end; Secondary drainage ditches are arranged on both sides of the main drainage ditch and at the toe of the slope of the side slope of the landfill, and one end of the secondary drainage ditch is higher than the other end; A plurality of main drainage pipes are arranged at the bottom of the main drainage ditch; Secondary drainage pipes are arranged at the bottom of the secondary drainage ditches; A collection well is arranged at the toe of the slope of the side slope of the landfill near the other end of the main drainage ditch and is communicated with the other ends of the main drainage pipes and the secondary drainage pipes; A pumping drainage pipe has one end arranged inside the collection well; A flushing pipe is communicated with the one ends of the main drainage pipes and the secondary drainage pipes, and the flushing pipe is arranged on the side slope of the landfill on the side far from the collection well; A plurality of second pipe holes are opened on the pipe walls of different main drainage pipes in different landfill areas, and a plurality of third pipe holes are opened on the pipe walls of the secondary drainage pipes in the landfill areas; Main gate valves are arranged on the main drainage pipes in the landfill areas where the second pipe holes are located, the main gate valves are arranged inside the main drainage pipes near the other end of the main drainage ditch, secondary gate valves are arranged on the secondary drainage pipes in the landfill areas where the third pipe holes are located, and the secondary gate valves are arranged inside the secondary drainage pipes near the other end of the secondary drainage ditch; A plurality of the landfill areas are arranged along the axial direction of the main drainage ditch; The number of the main drainage pipes is equal to the number of the landfill areas, and the plurality of main drainage pipes are arranged side by side.

2. The leachate drainage system of the landfill according to claim 1, characterized in that First guide slopes and second guide slopes are respectively arranged on both sides of the main drainage ditch and the secondary drainage ditches, one end of the first guide slope close to the main drainage ditch is lower than the end far from the main drainage ditch, and one end of the second guide slope close to the secondary drainage ditch is lower than the end far from the secondary drainage ditch.

3. The leachate drainage system of the landfill according to claim 1, characterized in that The cross-sectional shape of the partition dam is trapezoidal, and the outer side of the partition dam is coated with an anti-seepage layer, and the anti-seepage layer is connected with the anti-seepage layer at the bottom of the landfill.

4. The leachate drainage system of a landfill site according to claim 1, wherein First cushions and second cushions are respectively arranged at the bottoms of the main drainage ditch and the secondary drainage ditches, the main drainage pipes and the secondary drainage pipes are respectively arranged on the upper sides of the first cushions and the second cushions, and first fillers are filled outside the main drainage pipes and the secondary drainage pipes in the main drainage ditch and the secondary drainage ditches, and a first anti-filter layer is wrapped outside the first fillers.

5. The leachate drainage system of a landfill site according to claim 1, characterized in that, A third cushion is arranged at the bottom of the collection well, a second filler is filled inside the collection well, and a second anti-filter layer is wrapped outside the second filler.

6. The leachate drainage system for a landfill according to claim 5, wherein The exhaust pipe includes a horizontal portion and an inclined portion. One end of the horizontal portion is connected to the inclined portion to form a broken line shape. The horizontal portion is disposed above the third cushion layer at the bottom of the collection well. A plurality of first pipe holes are formed in the pipe wall of the horizontal portion. A blocking baffle is provided at the other end of the horizontal portion. The inclined portion is disposed on the slope near the collection well. A first blind ditch is provided on the slope near the collection well. The inclined portion is disposed in the first blind ditch and filled with clay or concrete.

7. The leachate drainage system of the landfill according to claim 1, characterized in that, A second blind ditch is provided on the slope on the side far from the collection well. The flushing pipe is disposed in the second blind ditch and filled with clay or concrete.

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