JP4363079B2 - Method and system for promoting stabilization of landfill waste - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention provides a method for promoting stabilization of landfill waste andsystemIn particular, the amount of rainwater infiltrated into landfill waste is controlled to stabilize landfill waste, and other groundwater is prevented from penetrating into landfill waste. A method for promoting stabilization of landfill waste suitable for preventing pollution such assystemAbout.
[0002]
[Prior art]
Regarding the disposal method of general and industrial waste, environmental pollution around the disposal site is a problem. This is because the infiltrated water such as rain is contaminated when penetrating the landfill waste, and flows into the surrounding groundwater and contaminates. Therefore, in order to prevent environmental pollution, it is important to avoid contact between pollutants and groundwater. One of the preventive measures is a waste landfill structure using a multi-layer cover. FIG. 6 shows a longitudinal sectional view thereof. In FIG. 6, the multi-layer covering soil covering the waste surface is formed by applying a water guide gradient to the surface portion of the recessed land 1 and covering it with the locally generated soil 2, and then laying the coarse particle layer 3 and subsequently the fine particle layer 4. A capillary barrier layer configured as described above is formed, and finally the entire structure is covered with locally generated soil and topsoil 5 having good water shielding properties. Here, the layer boundary between the fine grain layer 4 and the coarse grain layer 3 is given a gradient. This is because the fine-grained layer 4 having a large water-holding capacity composed of small grains is provided on the coarse-grained layer 3 having a large grain constituting the multi-layer covering soil, so that the permeated water due to rainfall or the like is stopped by the fine-grained layer 4. At the same time, a capillary barrier is used that applies a water-conducting gradient to the cover soil and flows down sideways along the boundary surface between the coarse-grained layer 3 and the fine-grained layer 4.
[0003]
As a result, the permeated water that has passed through the surface of the multi-layered soil and infiltrated into the fine-grained soil and moved downward changes the direction of flow near the boundary surface with the coarse-grained soil to the side along the gradient, and retains the water in the fine-grained soil. The water is then collected by flowing down. For this reason, the penetration of rainfall infiltrated water and the like into the waste layer is prevented.
[0004]
[Patent Document 1]
JP 2001-17933 A
[0005]
[Problems to be solved by the invention]
However, the law stipulates that after the completion of such waste landfill or after the disposal site is closed, the water and gas generated from the disposal site are controlled. In order to stop this management, it is necessary that the leachate before treatment falls below the drainage standard value and the like, and it is necessary to suppress the generation of gas and heat. This state is called “stabilization”. After landfill, if the bottom impermeable layer is complete and the possibility of environmental pollution to the surrounding area is small, it is appropriate to stabilize the underground waste layer rather than blocking moisture at all. There are many cases that require a lot of moisture. As a conventional construction method in this case, a water injection pump is generally used, and there is an inconvenience that requires a power source in mountainous areas. In particular, in order to make landfill waste harmless, it is necessary to chemically stabilize it at an early stage, but it is practically impossible to continue management using power over a long period of time. . In addition, when aeration is performed to stabilize landfill waste, it is necessary to install a facility for aeration, and even in this case, an effective method has not yet been established.
[0006]
Moreover, since gas may be generated from landfill waste, a location for discharging this gas is required. Moreover, it is necessary to promote stabilization by discharging gas generated from landfill waste and supplying air to the waste layer. Further, the permeated water needs to be drained, appropriately treated and discharged in order to avoid staying at the bottom. In addition to rainfall, landfill waste contains running water that flows into the landfill from the surrounding area, so a groove to collect water is required on the surface.
[0007]
In this way, it is necessary to keep the underground waste in a stable and constant condition. According to the above-mentioned multi-layer covering soil, the permeated water is drained along the gradient and the interior of the landfill is blocked, so that it is not suitable for such a place.
[0008]
  Therefore, the present invention has been made to solve the above-described problems in the multi-layered soil, and does not require a power source, and can be used for landfill waste that can promote stabilization of landfill waste using natural materials. Stabilization promotion method andsystemThe purpose was to provide.
[0009]
[Means for Solving the Problems]
  In order to achieve the above object, a method for promoting stabilization of landfill waste according to the present invention comprises a coarse grain layer formed on an upper surface of a landfill waste protection layer having permeability and a fine grain layer on the top layer. The downstream side of the gradient while shielding the permeated water by the permeated water capillary barrier layer with the gradientA portion shorter than the water retention limit distance of the osmotic water capillary barrier layerAnd collects and drains the water, and the permeated water capillary barrier layerInfiltration part consisting of sand holes provided in coarse particle layer and barrier provided in fine particle layerThe landfill is stabilized by dispersing and introducing a part of the shielded penetrating water from the above into the landfill waste and allowing it to permeate in a small amount. In addition, waste water treatment and air supply from the lower part of the landfill waste may be performed.
[0010]
  The system for promoting stabilization of landfill waste according to the present invention is a permeation method in which a gradient layer comprising a coarse particle layer and a fine particle layer laminated on the upper surface is disposed on the upper surface of a landfill waste protection layer having permeability. A water capillary barrier layer is formed, and drainage is provided within the water retention limit distance of the permeated water capillary barrier layer on the lower gradient side of the permeated water capillary barrier layer so that permeated water can be discharged. Disperse and form a plurality of permeation parts consisting of sand holes provided in the coarse-grained layer and barriers provided in the fine-grained layer for introducing and penetrating a portion of the permeated water permeated into the landfill waste into the landfill. Thus, the composition is characterized in that the landfill is stabilized by shielding the permeated water and conducting a small amount of penetration into the landfill waste at the same time.
  Further, the permeated water capillary barrier layer has a multilayer structure along the gradient.
[0011]
  Also,The drainage groove has a structure in which fine-grained sand connected to the fine-grained layer is spread inside the groove.
  In addition, a surface drainage groove is formed on the surface of the cover soil layer laid on the upper surface layer of landfill waste, and the running water flowing into the disposal site is collected and drained.
[0012]
  Degassing pipe that protrudes from the waste layer of landfill waste to the surface of the cover layerAnd a gas vent pipe extending from the waste layer to the coarse grain layer, and a vent hole is formed on the surface where the coarse grain layer is in contact with the gas vent pipe projecting from the waste layer of the landfill waste to the surface of the cover layer. Forming and flowing the generated gas of the waste layer from a gas vent pipe reaching from the waste layer to the coarse particle layer into a gap in the coarse particle layer, and passing the gas laterally through the gap of the coarse particle layer. Move to the outside via a vent pipe that protrudes from the vent hole to the surface of the cover layerIt is configured to stabilize the discharged and landfill.
  A degassing pipe protruding from the waste layer of the landfill waste to the surface of the soil covering layer, and a degassing pipe in the coarse particle layer in the coarse particle layer contacting the degassing pipe reaching from the waste layer to the coarse particle layer And connecting the gas vent pipe protruding from the waste layer of the landfill waste to the surface of the cover layer and the gas vent pipe reaching from the waste layer to the coarse grain layer by the gas vent pipe in the coarse grain layer. IsThe coarse-grained stone layer has a coarse-grained degassing promoting tube.
[0013]
  In addition, a drainage gradient is formed in the lower region of the waste layer of landfill waste, and a drainage drainage culvert with holes is formed, along with the water collection in the waste layer. To stabilize the landfill by supplying air stablyThe configuration.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
  The following is a method for promoting the stabilization of landfill waste according to the present invention.systemThe embodiment will be described in detail with reference to the drawings.
  In order to promote the stabilization of landfill waste, control of infiltrated water in the multi-layered soil by rainfall, etc., drainage of excess infiltrated water and securing appropriate retained water in the waste layer, and gas generated inside the waste layer Is to control the discharge of air and the supply of air. In addition, the drainage function that reduces the flowing water from the landfill area into the disposal site and the groundwater flowing from the landfill area are prevented from flowing in by the impermeable layer.
[0016]
Fig. 1 shows a cross-sectional installation view of a landfill waste stabilization promotion system. The place where the waste 10 is landfilled is set as a landfill area by, for example, creating a recessed land using a gentle slope. Of course, you may build on a flat ground. The water shielding layer 12 is laid on the mountain side slope, the bottom, and the left and right slopes of the depression. The material of the water shielding layer 12 is not particularly limited as long as it can prevent permeation of water. For example, a water-impervious soil that has the ability to delay the diffusion of harmful substances produced by mixing soil produced by excavation of depressions and clay mineral bentonite that swells when in contact with water and makes it very difficult for water to penetrate. May be laid in layers. The water shielding layer 12 is laid at the bottom of the recessed area, and is laid so as to rise upward along the mountain side and right and left slopes from the peripheral edge. Thereby, it is possible to prevent groundwater around the recessed area from entering the recessed area.
[0017]
The surface of the water-impervious layer 12 is provided with a water guide gradient from the lower end of the slope side on the mountain side toward the valley side. A plurality of drainage culverts 14 are laid in parallel at appropriate intervals along the slope surface. The drainage culvert 14 is formed by opening a large number of holes in the pipe wall, and collects water from the surrounding soil layer and flows it downstream of the gradient. This end-of-drain water culvert 14 communicates with a water treatment facility 15 formed on the valley side. Thereby, the sewage flowing through the end-of-end water collecting underdrain 14 is stored and purified.
[0018]
Next, the waste 10 is usually put into divided areas in the area where the water shielding layer 12 is laid. When the waste 10 becomes full for each section, the upper surface portion of the waste 10 is now processed. A water guide gradient is attached to the upper surface portion of the thrown-in waste 10, and the surface of the waste 10 is set to a condition in which the rain permeated water is likely to flow down naturally. This gradient may be set so as to be inclined in the left-right direction from the ridge line portion along the center line of the recessed area while being set in the inclination direction of the gently inclined area where the recessed area is formed. The upper surface of the waste 10 with the water guide gradient is covered with a protective layer 16. The protective layer 16 can control the permeability as needed. Furthermore, a so-called capillary barrier layer is laid on the upper surface of the landfill waste protection layer 16. First, a coarse particle layer 18 having a small water retention capacity is laid on the lower layer side. The coarse layer 18 may be formed of gravel, gravel, crushed stone, or the like. Next, a fine grain layer 20 having a large water retention capacity is laid on the upper surface of the coarse grain layer 18. The fine-grained layer 20 may be made of sand or the like having such a size that the infiltrated water can maintain the water retention state by the surface tension action. In this way, the capillary barrier layer is provided with a fine-grained layer 20 having a large water retention capacity, which is composed of small grains, on the coarse-grained layer 18 having large grains. While being retained in the layer 20, it flows down according to the gradient along the boundary surface between the coarse-grained layer 18 and the fine-grained layer 20. In this manner, the protective layer 16, the coarse grain layer 18, and the fine grain layer 20 are sequentially laminated on the upper surface of the waste 10, and then covered with the soil covering layer 22. If this soil covering layer 22 is completely impermeable, moisture will not be supplied to the landfilled waste, and it will take a long time to stabilize, so that the permeated water can be controlled. is necessary.
[0019]
Moreover, in this embodiment, in order to drain flowing water such as rainfall flowing from the periphery of the landfill, a surface drainage groove 24 is provided in the cover soil layer 22 on the surface of the landfill. Here, it is predicted that the portion of the landfill where the waterfall deformation is greatest due to the groundwater fall in the landfill is a concave land with the largest landfill depth. Are arranged to gather in the center. Further, the drainage groove at the center may be a polyethylene pipe or a lightweight material drainage groove so that it can follow the deformation. Depending on the installation location of the landfill, the surface drainage can be efficiently performed by branching the plurality of drainage grooves into the shape of branches and leaves with the surface drainage groove 24 as the center.
[0020]
Further, in order to drain the rain permeated water that has been submerged from the surface of the soil covering layer 22, it can be drained to the side using a multilayer soil covering composed of the fine grain layer 20 and the coarse grain layer 18. In this water collection, a drainage groove 36 is installed based on the drainage distance of the permeated water obtained from the water-blocking performance evaluation test of the multi-layered soil. That is, by creating a simulated structure of the capillary barrier layer and determining the water retention limit distance (drainage distance) by the fine-grained layer 20, if the water is collected within a position corresponding to the drainage distance, landfill waste due to water retention failure The rainwater is prevented from penetrating excessively.
[0021]
On the other hand, the gas generated from the waste is discharged from the waste layer by installing a gas vent pipe 26 protruding from the waste layer to the surface of the cover layer 22. A coarse layer degassing pipe 28 that reaches the coarse layer 18 from the waste layer is disposed. This is connected to a gas vent pipe 26 that reaches the surface of the soil covering using the gaps in the coarse particle layer 18 to release the gas to the outside.
[0022]
In addition, since the above-mentioned drainage culvert 14 has a relatively large cross-section and is formed with a large number of holes in the pipe wall, the contaminated water that has permeated from the soil covering surface and has permeated the waste 10 can be obtained. Collects water and supplies air to the waste layer.
[0023]
For excessive permeated water entering from the surface of the multi-layered soil, lateral drainage by the capillary barrier layer may be performed. FIG. 2 shows a sectional view of the installation of the capillary barrier drainage system. In FIG. 2, (a) shows the drainage system of the capillary barrier layer which is easy to take a gradient. (b) shows a drainage system of a capillary barrier layer having a gentler slope than (a). (c) shows the drainage system of the capillary barrier layer in a flat area with a small gradient.
[0024]
In the drainage system of the capillary barrier layer having a gradient in FIG. 2 (a), the capillary barrier layer is provided with a protective layer 16 on the waste (not shown), and the upper layer has coarse stones 30, fine sand 32, Lay in the order of covering soil 34. A drainage groove 36 is installed according to the drainage distance of the permeated water from the surface layer based on the water-impervious performance evaluation test. The drainage groove 36 is a water-impervious U-shaped groove, and coarse crushed stones 38 and coarse crushed stones 30 are laid in order from the lower layer to the bottom. A wall surface connecting the 30 layers and the coarse stone 30 at the bottom of the groove is formed. Furthermore, fine sand 32 connected to the fine sand 32 layer is spread inside the groove.
[0025]
As a result, rainfall or the like that has penetrated from the surface of the landfill area of the waste passes through the cover soil 34 and flows down the boundary surface of the fine sand 32 and the coarse stone 30 according to the gradient, and from the upper part of the infiltration upstream of the drainage groove 36 to the groove It flows into the fine sand 32 inside. Further, the coarse stone 30 on the upper side surface on the downstream side of the longitudinal section of the drainage groove 36 is inclined to reduce the permeation of the permeated water into the lower layer. In order to prevent water from flowing into the drainage groove 36, a coarse crushed stone 38 is installed at the bottom of the groove, and a perforated tube is installed at the bottom of the groove to secure a drainage cross section as necessary. It is possible to drain water. The drainage groove 36 may be made of a rigid body such as concrete or resin as long as it has a water shielding effect. Further, a water shielding sheet 40 is disposed on the upper portion of the drainage groove 36 as necessary. This is for preventing permeation of the portion where water at the flow end portion of the permeated water easily penetrates into the lower layer, and the material is not particularly limited as long as it has a water shielding effect. The arrows in the figure indicate the direction of water flow such as rainfall.
[0026]
FIG. 2 (b) shows a drainage system of a capillary barrier layer having a gentler slope than that of (a), and the construction of the soil covering is the same as described above. In this case, the capillary effect cannot be expected because the gradient of the capillary barrier layer is gentle. Therefore, in order to secure the gradient and apply the lateral drainage, a stepwise gradient is provided on the drainage downstream side of the drainage groove 36 longitudinal section. This gradient is arranged at a position higher than the drainage outlet on the upstream side, and when the side drainage is performed, the permeated water flows into the drainage groove. Furthermore, the drainage groove 36 is installed at a position that takes into account the drainage distance based on the water shielding performance evaluation test. The inside of the groove has the same configuration as described above, and a water shielding sheet 40 is provided at the end of the permeated water flow as necessary.
[0027]
Although the above-mentioned drainage system functions effectively in a sloped area, it may be difficult to form a slope depending on the landfill location of the waste. In the drainage system of the capillary barrier layer in the plane area of FIG. 2 (c), the structure of the covering soil is the same as described above. In the case of the above-mentioned flat land, when the capillary barrier layer cannot have a single slope, the slope between the drain groove 36 and the drain groove 36 is positively inclined to form a gradient in the capillary barrier layer. And the drainage groove | channel 36 is installed in the trough part and an edge part. The drainage ditch is installed at a position that considers the drainage distance (water retention limit distance). The inside of the groove has the same configuration as described above, and a water shielding sheet 40 is provided at the end of the permeated water flow as necessary. In this embodiment, the coarse-grained crushed stone 38 is installed at the bottom of the groove so that water does not flow inside the drainage groove 36. In addition to this, the coarse-grained crushed stone 38 is not used. You may spread the layer as it is.
With this configuration, leachate from the surface layer is drained without contact with waste, so there is little risk of contamination. Accordingly, it can be drained as it is as the surface drainage.
[0028]
On the other hand, in a capillary barrier layer having a coarse particle layer as a lower layer and a fine particle layer as an upper layer, if the drainage distance due to rainfall or the like is too long, pore water cannot be retained and a portion where permeated water falls will be generated. Rainfall, etc. that falls on the coarse-grained layer easily penetrates downward because there are gaps and little water retention. There is a case where the above-mentioned drainage groove cannot be installed at this falling point. In addition, when forming a multi-layered soil, a high-quality material may not be used due to cost and material availability. Depending on the material, there are cases in which the drainage distance cannot be obtained, and the drainage distance may affect performance due to the material (type of sand).
[0029]
Therefore, the drainage distance can be extended or extended by using a double structure in which the permeated water capillary barrier layer having the coarse-grained layer 18 as the lower layer and the fine-grained layer 20 as the upper layer is provided in the lower stage according to the drainage distance. It becomes. A multi-capillary barrier layer structure for reducing the falling water of the permeated water into the coarse particle layer 18 will be described with reference to the cross-sectional view of FIG. The protective layer 16 is laid on the waste layer 42, and the coarse layer 18, the fine particle layer 20, the coarse particle layer 18, the fine particle layer 20, and the soil covering layer 22 are laid in that order from the lower layer side. The protective layer 16 and the soil covering layer 22 are configured so as to be able to control the permeability as needed, and the permeability is controlled by appropriately combining bentonite mixed soil and sheets.
[0030]
Moreover, you may install the nonwoven fabric 44 in the boundary part of the coarse grain layer 18 and the fine grain layer 20 which form a permeated water capillary barrier layer as needed. This prevents, for example, the mixing of the fine-grained layer and the coarse-grained layer when an operator passes over the coarse-grained layer and the fine-grained layer during construction. In other words, when the fine-grained layer and the coarse-grained layer are mixed locally, the water retention capacity due to the capillary effect at that portion cannot be maintained, and the permeated water is prevented from falling.
[0031]
Thereby, rain or the like permeates from the surface of the covering soil, and the first capillary barrier layer composed of the fine-grained layer 20 and the coarse-grained layer 18 moves laterally by the capillary action of the fine-grained layer 20 and can be drained. Even when the water falls to the lower layer beyond the upper limit, the second capillary barrier layer formed in the lower layer further moves laterally by capillary action of the fine-grained layer 20. Since a certain amount of drainage is maintained even in the upper fine-grained layer, it is possible to postpone the rain that has fallen to the side by making this capillary barrier layer a two-layer structure. The capillary barrier layer may be installed at a location where the drainage distance can be cut according to the installation location, or the entire installation location may be multilayered. Further, in the present embodiment, the case where two capillary barrier layers are used has been described. However, based on the method for evaluating the water-blocking performance of the capillary barrier layer, the capillary barrier layer is divided into two or more layers according to the types of coarse and fine layers. It may be configured.
[0032]
Here, the sand used for the fine-grained layer 20 forming the permeated water capillary barrier layer is preferably a fine-grained sand. However, in addition to this, even if a high-quality material cannot be obtained for cost reduction, the above-described barrier is used. Any pulverized material suitable for the capillary barrier layer may be used based on the aqueous evaluation method. For example, applicable secondary products such as crushed sand and pulverized products, porous fabrics such as cotton-like non-woven fabrics and sponges, or slag pulverized products, artificial pulverized products, textile products, plastic porous bodies, ceramics, sintered bodies Alternatively, a compact or powder of a porous material, an aggregate of a powder material, a pulverized material of a porous material, an aggregate of a powder fluid of a porous material, or a powder of a raw material of a porous material can be substituted. However, if the layers constituting the multilayer are made thicker, the capillary barrier is affected, so it is desirable to use a material that can be made as thin as possible.
[0033]
FIG. 4 is a diagram showing a method for controlling the amount of permeated water in the capillary barrier layer. 4 (1) is a side sectional view of the capillary barrier layer, and FIG. 4 (2) is a plan view taken along the line AA in FIG. 4 (1).
[0034]
In order to control the permeated water into the waste layer, an entry port for water to be immersed downward may be provided in a location where moisture is required in advance. Therefore, a hole into which permeated water enters may be formed at the boundary surface between the fine-grained layer 20 and the coarse-grained layer 18 of the capillary barrier layer laid on the upper surface of the waste layer (not shown). For this purpose, the flowing water surface along the boundary surface of the fine-grained layer is divided by the wall of the coarse-grained material and drawn into the downward sand layer. Note that the position of the permeation hole may be determined by estimating the permeation amount from the ratio between the drainage width and the hole diameter shared by the drainage groove, assuming the drainage area upstream of the hole.
[0035]
In FIG. 4 (1), the degassing pipe 26 is a pipe that protrudes and penetrates from the waste layer to the surface of the multi-layer covering soil including the capillary barrier layer and has a T-shaped tip portion and can be vented from both end faces. A barrier 48 of coarse stone 30 is formed on the outer periphery of the gas vent pipe 26. As a result, the permeated water that has permeated from the surface of the soil covering layer and has flowed due to the water guiding gradient at the boundary surface between the fine-grained layer 20 and the coarse-grained layer 18 has coarse grains below the barrier 48 formed on the outer periphery of the gas vent pipe 26. It penetrates into layer 18 and penetrates further into the waste layer below. In addition to this, in order to evenly permeate the landfill waste where water supply is required, coarse particles are provided downstream of the water introduction gradient at the boundary surface between the fine particle layer 20 and the coarse particle layer 18. A barrier 48 of the stone 30 is formed, and a sand hole 46 of the fine-grained layer 20 is installed upstream thereof. As a result, the permeated water that has permeated from the surface of the soil covering layer and has flowed due to the water guide gradient at the boundary surface between the fine-grained layer 20 and the coarse-grained layer 18 penetrates into the coarse-grained layer 20 below at the sand hole 46 and the barrier 48 portion. Then, it further enters the waste layer 42 below. Therefore, since the permeated water inlet is secured by the outer peripheral portion of the gas vent pipe 26 formed in the multi-layer cover soil and the sand hole 46, a part of the permeated water permeated from the landfill surface is used as a lower waste layer. It becomes possible to supply to. On the other hand, excessive permeated water can flow into the lateral drainage grooves and collect water by capillary action of the fine-grained sand layer of the capillary barrier layer as before, following the water conveyance gradient.
[0036]
FIG. 5 is a diagram showing a method for venting the capillary barrier layer. The degassing of the waste layer may be performed by arranging a degassing pipe 26 that leads from the waste layer to the surface of the cover soil. Moreover, if a degassing pipe that leads from the waste layer to the coarse-grained layer 18 is formed using the gaps in the coarse-grained stone layer that constitutes the capillary barrier layer, it is shorter than the degassing pipe that reaches the soil covering surface. Since it can be supplemented with pipes, there are fewer vent pipes on the ground surface, making it easier to use land and at the same time reducing costs. If ventilation is required, a perforated tube is placed in the layer to improve air permeability.
[0037]
In FIG. 5, the multi-layer covering soil has a structure in which a protective layer 16, a coarse-grained layer 18, a fine-grained layer 20, and a covering soil layer 22 are laid in this order from the bottom on the surface of a waste layer (not shown). The gas vent pipe 26 projects from the waste layer (not shown) through the surface of the soil covering layer 22, has a T-shaped tip and can be vented from both end faces of the pipe, and releases the gas generated in the waste layer to the outside. It is a mechanism to do. In the present embodiment, the shape of the gas vent pipe 26 has been described as having a T-shaped tip, but the shape is not limited to this shape as long as ventilation is possible from both end faces of the pipe.
[0038]
On the other hand, since the coarse grain layer 18 forming the capillary barrier layer uses a coarse stone, there is a gap between the stones in this layer. If this gap is utilized, the gas generated inside the landfill can be moved laterally and discharged to the outside via the gas vent pipe 26. Therefore, a tube extending from the waste layer to the coarse particle layer 18 may be formed. The coarse layer degassing pipe 28 penetrates from the waste layer to the coarse layer 18. Further, a hole through which exhaust gas passes is formed in the surface in contact with the gas vent pipe 26 and the coarse particle layer 18.
[0039]
Thus, the gas generated in the waste layer flows into the coarse particle layer 18 through the degassing pipe 26 and the coarse particle degassing pipe 28, and the degassing pipe from the hole where the coarse particle layer 18 and the degassing pipe 26 are in contact. 26, and can be discharged to the outside through a discharge port protruding on the surface of the soil covering layer. Further, the connection from the coarse layer degassing pipe 28 to the degassing pipe 26 is performed by a perforated pipe or the like according to the necessity of air supply / exhaust, and the coarse layer degassing pipe 27 is formed. You may provide the side exhaust pipe 29 extended to a part.
[0040]
The following cases can be considered for rainfall flowing into landfill waste.
1. Rainfall penetrating from landfill surface
2. Surface water flowing into the landfill from around the landfill
3. Groundwater flowing from the landfill area
[0041]
Of these, for 1, the amount of water can be reduced by the multi-layer cover soil laid on the upper surface of the waste layer and the multi-layer cover soil. Regarding 2, the amount of water flowing from the landfill area can be reduced by installing a surface drainage groove in the cover soil, which is the surface layer. Furthermore, regarding 3, the inflow of groundwater from the periphery can be reduced by covering the lower layer of the waste layer with a water shielding layer.
[0042]
【The invention's effect】
As described above, according to the present invention, while the permeated water capillary barrier layer is provided with a coarse layer formed on the upper surface of the landfill waste and a fine grain layer on the coarse layer, the permeated water is shielded on the downstream side of the gradient. The landfill is stabilized by systematically dispersing and draining a part of the shielded permeated water by the permeated water capillary barrier layer into the landfill waste by systematically dispersing and infiltrating a small amount. Since it is configured so that the permeated water is shielded and the small amount of infiltration into the landfill waste is performed at the same time, the stabilization of the landfill is promoted, and there is no need to use power such as a water injection pump. The layer itself can also be constructed using natural materials, and an excellent effect can be achieved that landfill waste can be stabilized.
[0043]
In addition, a degassing pipe extending from the waste layer to the coarse stone layer is formed while forming a degassing pipe that protrudes and penetrates from the waste layer of the landfill waste to the surface of the cover soil layer, and a large distribution is provided at the bottom of the waste layer. A water pipe was arranged to supply air. As a result, it is possible to promote the stabilization of the landfill by promoting oxidation, biodegradation, etc. by supplying appropriate air and moisture to the waste layer and discharging the generated gas.
[0044]
Further, by installing a non-woven fabric between the fine-grained layer and the coarse-grained layer that form the permeated water capillary barrier layer, mixing of the upper and lower layers can be prevented and the water retention effect of the capillary barrier layer can be maintained. Furthermore, by using the fine or coarse layer constituting the osmotic water capillary barrier layer as a pulverized product whose particle size is adjusted by pulverizing solids, it can be used as an inexpensive alternative or recycled product to replace crushed sand. The next can be used.
[Brief description of the drawings]
FIG. 1 shows an installation cross-sectional view of a landfill waste stabilization promotion system.
FIG. 2 shows an installation cross-sectional view of a multi-layer covered soil drainage system.
FIG. 3 is a cross-sectional view showing a multiple-type multilayer soil covering structure.
FIG. 4 is a diagram showing a method for controlling the amount of permeated water in a multi-layer soil covering.
FIG. 5 is a diagram showing a degassing method for multilayer covering soil.
FIG. 6 is a vertical cross-sectional view of a waste landfill structure using multi-layer cover soil.
[Explanation of symbols]
1 ......... Recessed ground, 2 ......... Locally generated soil, 3 ......... Coarse-grained layer, 4 ......... Fine-grained layer, 5 ......... Top soil, 10 ......... Waste, 12 ......... Water shielding , 14 ……… Flower culvert, 15 ……… Water treatment facility, 16 ……… Protective layer, 18 ……… Coarse grain layer, 20 ……… Fine grain layer, 22 ……… Soil cover layer, 24... Surface drainage groove, 26... Degassing pipe, 27... Coarse grain gas venting pipe, 28... Coarse grain gas venting pipe, 29. …… Coarse stone, 32 ……… Fine sand, 34 ……… Soil, 36 ……… Drain, 38 ……… Coarse crushed stone, 40 ……… Waterproof sheet, 42 ……… Waste layer 44 ......... Nonwoven fabric, 46 ......... Sand holes, 48 ......... Barrier.

Claims (9)

The downstream side of the gradient while shielding the osmotic water by the osmotic capillary barrier layer with the gradient consisting of the coarse layer formed on the upper surface of the landfill waste protection layer with permeability and the finer layer above it From the sand holes provided in the coarse layer of the permeated water capillary barrier layer and the barrier provided in the fine particle layer, the water is collected and drained at a location shorter than the water retention limit distance of the permeated water capillary barrier layer. A method for promoting stabilization of landfill waste, comprising stabilizing the landfill by introducing a part of the shielded permeated water by the permeation portion into the landfill waste and allowing it to permeate in a small amount. The method for promoting stabilization of landfill waste according to claim 1, characterized in that wastewater treatment and air supply from a lower part of the landfill waste are performed. An osmotic capillary barrier layer having a gradient layer composed of a coarse particle layer and a fine particle layer laminated on the upper surface is formed on the upper surface of the landfill waste protection layer having permeability. A drainage groove is provided within the water retention limit distance of the osmotic water capillary barrier layer on the lower side of the gradient so that the osmotic water can be discharged. Infiltrate the water into the landfill and disperse a plurality of permeation parts consisting of sand holes provided in the coarse particle layer and barriers provided in the fine particle layer, thereby shielding the permeated water and reducing the amount to the landfill waste. A system for promoting stabilization of landfill waste, characterized in that the infiltration is performed simultaneously to stabilize the landfill. 4. The system for promoting stabilization of landfill waste according to claim 3, wherein the permeated water capillary barrier layer has a multilayer structure along the gradient. 4. The system for promoting stabilization of landfill waste according to claim 3 , wherein the drainage groove is laid with fine-grained sand connected to the fine-grained layer inside the groove . The system for promoting stabilization of landfill waste according to claim 3, wherein a surface drainage groove is formed on the surface of the covering soil layer laid on the upper surface layer of the landfill waste, and the running water flowing into the disposal site is collected and drained. A degassing pipe that protrudes from the waste layer of the landfill waste to the surface of the cover layer and a degassing pipe that reaches from the waste layer to the coarse particle layer are provided.
A vent hole is formed on the surface where the coarse layer is in contact with the degassing pipe projecting and penetrating from the waste layer of the landfill waste to the covering soil layer surface,
The gas generated in the waste layer is allowed to flow from a degassing pipe reaching the coarse particle layer to the gap in the coarse particle layer, and the gas is moved laterally through the gap in the coarse particle layer. 4. The landfill waste stabilization promotion system according to claim 3, wherein the landfill waste is stabilized by being discharged to the outside through a vent pipe projecting from the vent hole to the surface of the cover layer. . A degassing pipe protruding from the waste layer of the landfill waste to the surface of the soil covering layer, and a degassing pipe in the coarse particle layer in the coarse particle layer contacting the degassing pipe reaching from the waste layer to the coarse particle layer Provided,
The degassing pipe protruding from the waste layer of the landfill waste to the surface of the soil covering layer and the degassing pipe reaching from the waste layer to the coarse particle layer are connected by the degassing pipe in the coarse particle layer. The stabilization promotion system for landfill waste according to claim 7, By forming a diversion culvert with a water conveyance gradient in the lower area of the waste layer of landfill waste, air in the waste layer is collected together with the water in the waste layer. The stabilization promotion system for landfill waste according to claim 3, wherein the landfill is stabilized by stably supplying the landfill.

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