JP5537207B2 - New construction method for waste final disposal site with landfill structure with bottom and slope - Google Patents

Description

  The present invention relates to a construction method for a waste final disposal site that does not use a drainage pipe and has a landfill structure having a bottom surface and a slope. More specifically, in the present invention, the surface of a plurality of strip-shaped strips made of a synthetic resin provided with a plurality of openings is provided on a substantially entire surface of a water shielding sheet laid on substantially the entire bottom surface and / or slope. Laying flexible geocell structures that are joined together to form a plurality of cells alternately spaced in parallel when the adjacent strips are pulled apart in a direction perpendicular to the surface Filling and compacting crushed stones and / or chestnuts in the cells to form a geocell structure layer in which the crushed stones and / or chestnuts are sealed; final disposal generated by precipitation in the geocell structure layer The function of collecting leachate from the waste, the function of the air flow path required for the decomposition of the final waste by aerobic microorganisms, and the function of the degassing path generated from the final waste. Base and slope, characterized by being combined About the construction methods of the final waste disposal sites that exhibit the landfill structure with.

As shown in FIG. 1, conventionally, leachate drainage facilities at waste landfill sites consist of the following:
Bottom drainage pipe network,
Slope collection drainage pipe network,
Vertical drainage pipe,
Catchment pit, valve (leaching water intake equipment)
Water pipe,
Others (compartment dike) (see Non-Patent Document 1 below).

  As the drainage pipe, a perforated fume pipe or a perforated synthetic resin pipe is used, and a protective nonwoven fabric is laid on a water shielding sheet made of high-density polyethylene (HDPE) as shown in FIG. A covering material such as crushed stones and chestnuts is laid on top, and a drainage pipe is laid on top of it, and in order to secure the water collection function and reduce vertical load, A construction method in which the width is three times or more the pipe diameter and is placed on the pipe is common (see Non-Patent Document 1 below).

  Such construction methods require high levels of expertise in terms of the material and diameter of the drainage pipes, the diameter of the holes, the size of the holes, the location of the bottom and sloped drainage pipe networks, etc. It has become an obstacle when building many. In particular, the above-described collection and drainage pipe must be a pipe made of a material having a strength capable of withstanding the vertical load of the landfilled waste layer, and it may be difficult to obtain such a pipe.

  Therefore, as a landfill structure that does not require a leachate collection drain pipe, as shown in Patent Document 1 below, in the landfill structure for final disposal of waste, the entire bottom surface or part of the landfill is made of crushed stones and chestnuts. A function to collect and drain leachate generated from the waste layer by precipitation through the lower part of the Kuriishi layer and oxygen to aerobic bacteria that contribute to aerobic decomposition of the waste through the upper part of the Kuriishi layer A waste landfill structure characterized by having a supply function has been proposed (see claim 1 of Patent Document 1).

  However, in the landfill structure disclosed in Patent Document 1, the chestnut layer formed on the entire bottom surface of the landfill is shown in FIGS. 4, 6, and 8 of Patent Document 1 and “ The function of collecting leachate from the waste layer due to precipitation through the bottom and the function of supplying oxygen to aerobic bacteria that contribute to aerobic decomposition of waste through the top of the Kuriishi layer It is redeemed for having. Judging from the drawings of Patent Document 1, since the chestnut stone having a particle size of 5 to 15 cm forms a chestnut stone layer with a thickness of at least 10, the thickness of the whole chestnut stone layer is estimated to be at least 50 cm. .

As described in Cited Document 1, instead of the leachate collection drainage pipe, by providing a Kuriishi layer, the function of collecting leachate generated from the waste layer by precipitation through the bottom of the Kuriishi layer, and Kuriishi It seems that the function of supplying oxygen to the aerobic bacteria that contribute to the aerobic decomposition of the waste through the upper part of the layer and the function of degassing can be exhibited. In other words, since the leachate weekly drainage pipe facility usually composed of branch lines and trunk lines can be constructed in terms of the Kuriishi layer, the leachate weekly drainage and the diffusion of air necessary for aerobic decomposition of waste It has an advantageous structure, is easy to construct, and can be easily obtained.
However, as mentioned above, the Kuriishi layer is formed with a considerable thickness, so quality control (gap ratio management) is not easy when compacting crushed stones and Kuriishi, and the roadbed is loose. When the ground below changes greatly, there is a possibility that the kuriishi layer is unevenly distributed and the desired function cannot be exhibited. In addition, heavy loads are applied to some of the heavy equipment when crushing crushed stones and chestnuts, or when leveling and rolling down the input waste. There is a possibility that the sheet may be deformed or damaged, and the work efficiency of the compaction and rolling may be reduced.

  By the way, as disclosed in Patent Document 2, a reinforced cell structure system for sealing a substance is known. As shown in FIG. 3, the plastic soil sealing system disclosed in Patent Document 2 is a high-density polyethylene length in which cells are joined by ultrasonic joining so that their surfaces are alternately spaced and parallel. Because it is constituted by a piece, when the long piece is stretched in a direction perpendicular to its surface, the formed web section is apparently close to the honeycomb, presenting a sine wave or wave shape, The compartment is lightweight and is shipped in a folded form for ease of handling and installation. This plastic soil sealing system becomes a strong structure by filling the cell structure with sand, round rock, granular soil and aggregate, top soil, plant material, etc., and the product itself is lightweight. Because it is flexible, it is easy to install and is used for various purposes such as slope protection, river bank protection, and roadbed support.

  In the following cited document 3, for the purpose of greening the slope, a structure composed of a plurality of partitioned areas surrounded by a partition plate is arranged on the slope where a water shielding sheet is laid, and the structure Disclosed is a water shielding sheet slope structure characterized in that the covering soil can be held on the water shielding sheet by arranging the covering soil in the partition region. Such a structure seems to be a so-called “geocell”, but what is filled in the cell is soil for greening, not crushed stone or chestnut. Further, such a structure is installed only on the slope of the waste disposal site, and is not installed on the entire bottom surface.

  As described above, the so-called “geocell” structure itself is known, and although there is an example used for the purpose of filling soil for greening on the slope of a waste disposal site, Kuriishi layer filled with Kuriishi is formed on the entire surface of the water shielding sheet laid on the entire bottom surface and / or slope of the waste final disposal site, and is generated in the geocell structure layer by precipitation. The function of collecting and draining leachate from the final waste, the function of the air flow path required for the decomposition of the final waste by aerobic microorganisms, and the function of the vent for generating gas from the final waste There are still no cases where the two are shared.

JP-A-2005-270946 Japanese Patent No. 397667 JP 2002-11427 A

Waste Landfill Site Technical System Handbook (Editor: Final Disposal Site Technical System Study Group, Supervision: Masataka Hanashima, Nobutoshi Tanaka, Toru Furuichi, Publishing: Environmental Industry Newspaper), pages 382-389

  The problem to be solved by the present invention is the final disposal of waste, which is excellent in clearance ratio management and roadbed reinforcement effect when compacting crushed stones, and does not require the provision of drainage pipes, air flow paths, and gas vent flow paths It is to provide a new building construction method.

As a result of intensive studies and experiments, the inventors formed a geocell structure layer in which crushed stones and / or chestnut stones were sealed on substantially the entire surface of the water shielding sheet laid on the entire bottom surface and / or slope. As a result, the inventors have found that the above problems can be solved, and have completed the present invention.
That is, the present invention is as follows.

[1] A construction method for a waste final disposal site having a landfill structure having a bottom surface and a slope, and includes the following steps:
The surface of a plurality of strip-shaped strips made of synthetic resin provided with a plurality of openings on substantially the entire surface of the water shielding sheet laid on substantially the entire bottom surface and / or slope, Laying flexible geocell structures that are joined together to form a plurality of cells alternately spaced apart in parallel when pulled away from the plane; and crushed stone and Filling or compacting chestnut stone to form a geocell structure layer filled with the crushed stone and / or chestnut stone;
Including
Here, in the geocell structure layer, a function of collecting and draining leachate from the final waste generated by precipitation, and a function as an air flow path required for the decomposition of the final waste by aerobic microorganisms, The building construction method characterized by having a function as a degassing flow path generated from the final waste.

  [2] The construction method according to [1], wherein the synthetic resin is high-density polyethylene (HDPE).

  [3] The construction method according to [1] or [2], wherein the crushed stone has a particle size of 20 mm to 40 mm.

  [4] The construction method according to any one of [1] to [3], wherein the chestnut has a particle size of 5 to 15 cm.

[5] The thickness of the di can press structure layer is 100 to 200 mm, construction methods according to any one of [1] to [4].

  [6] The construction method according to any one of [1] to [5], wherein the geocell structure layer is stacked and stacked on a part of the water shielding sheet.

  [7] A waste final disposal site manufactured by the construction method according to any one of [1] to [6].

The construction method according to the present invention collects leachate from the final waste generated by precipitation on the geocell structure layer formed on substantially the entire surface of the water shielding sheet laid on substantially the entire bottom surface and / or slope. A drainage function, a function as an air flow path required for decomposing the final waste by the aerobic microorganism, and a function as a degassing flow path generated from the final waste can be combined.
In the construction method according to the present invention, due to the presence of the above-described geocell structure, it is not necessary to provide a drainage pipe, an air flow path, and a gas vent flow path that require a high degree of expertise in the design.
In particular, in the construction method according to the present invention, since the geocell structure layer can be formed on substantially the entire surface of the water shielding sheet including the slope, the various functions described above are exhibited not only on the bottom but also on the slope. Is done. That is, compared to the case where the chestnut layer is provided only on the bottom surface, the drainage flow path, the air flow path, and the gas vent flow path can be configured on a wider surface. The possibility of clogging and the like can be dramatically reduced. Furthermore, in response to the large area of the geocell structure layer, the amount of waste that can be landfilled per unit area can be increased.

Moreover, in the construction method according to the present invention, the use of the geocell structure makes it easy to manage the gap ratio at the time of compaction of crushed stone, and further improves the roadbed reinforcing effect. As a result, a crushed stone or chestnut layer that is highly resistant to changes in the ground under the water shielding sheet due to an earthquake or the like is provided. In addition, the load imposed by heavy machinery when crushing crushed stones and chestnuts or when leveling and rolling down the input waste is not concentrated and dispersed, and there is a risk of deformation or damage to the water shielding sheet. The work efficiency of compacting and rolling is also improved.

Furthermore, since the geocell structure to be used is flexible, the integral geocell structure can be installed on the surface including the boundary between the bottom surface and the slope.

It is a schematic diagram of the leachate drainage facility of the conventional landfill disposal site using a drainage pipe system. It is a laying schematic diagram of the conventional drainage pipe. It is a schematic diagram of the cell structure of a geocell. It is sectional drawing of the waste final disposal site which laid the geocell structure. It is the photograph replaced with drawing which shows the state which filled the crushed stone or chestnut stone in the cell structure body of a geocell.

Hereinafter, the present invention will be described in detail.
The present invention is a construction method of a waste final disposal site having a landfill structure having a bottom surface and a slope, and includes the following steps:
The surface of a plurality of strip-shaped strips made of synthetic resin provided with a plurality of openings on substantially the entire surface of the water shielding sheet laid on substantially the entire bottom surface and / or slope, Laying flexible geocell structures that are joined together to form a plurality of cells alternately spaced apart in parallel when pulled away from the plane; and crushed stone and Filling / consolidating chestnut stone to form a geocell structure layer in which the crushed stone and / or chestnut stone are sealed;
Including
Here, in the geocell structure layer, a function of collecting and draining leachate from the final waste generated by precipitation, and a function as an air flow path required for the decomposition of the final waste by aerobic microorganisms, It is related with the said construction method characterized by making it share the function as a degassing flow path which generate | occur | produces from a final waste.

    The geocell structure used in the present invention has a plurality of strip-like strips made of synthetic resin provided with a plurality of openings, when the strips adjacent to each other are pulled apart in a direction perpendicular to the plane. Is a flexible structure that is joined so as to be parallel to form a plurality of cells. As shown in FIG. 5, crushed stones or chestnuts are filled in the cells of the geocell structure. In this case, leachate, air, and gas can pass along a substantially horizontal plane by the plurality of openings provided in the long strip of the geocell structure band. In addition, since there is no geocell structure in the vertical direction inside the cell, the leachate, air, and gas can naturally pass along the substantially vertical direction.

Examples of the synthetic resin include high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP), polyamide, and polyester, and preferably high density polyethylene (HDPE).
The opening diameter can be 1 mm to 20 mm, preferably 8 to 12 mm.
The open area ratio of the cell can be 10% to 40%, preferably 15 to 30%.
The particle size of the crushed stone can usually be 20 mm to 40 mm, and the particle size of the chestnut can usually be 5 to 15 cm.
The thickness of the shiocell structure layer may be 75 mm to 300 mm, and preferably 100 to 200 mm.

Examples of the water shielding sheet include high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene, ethylene vinyl acetate copolymer (EVA), vulcanized rubber, vinyl chloride, thermoplastic rubber, polyurethane, and the like. A material made of a molecular material is used, and in addition to these water shielding materials, a material in which protective materials such as a nonwoven fabric, a woven fabric, and a resin foam are superimposed can be used. The thickness of the water shielding sheet can be 0.5 to 4 mm, and preferably 1 to 2 mm.
The geocell structure layer may be stacked on a part of the water shielding sheet. For example, even when such a geocell structure is laminated in multiple layers, leachate and air and gas can flow along a substantially horizontal surface and in a substantially vertical manner, ie, substantially omnidirectional. However, there is no change in being able to pass through.

For the purpose of cushions, filters, etc., laying of sheets, formation of filler layers such as earth and sand, filling with fillers at any position between the slope or bottom, water-impervious sheet, geocell structure, waste layer It is possible to install a bag body.
As the cushion material, a nonwoven fabric, a woven fabric, a three-dimensional network structure, a resin foam, or the like can be used.
The geocell structure can be laid on substantially the entire surface of both the bottom surface and the slope. In the landfill structure disclosed in Patent Document 1, the chestnut layer is not formed on the entire slope, and when the slope is a steep slope, it is difficult to form the chestnut layer and deposited on the slope. It was difficult to exert a drainage function and an air circulation function for the waste layer. On the other hand, by laying the geocell structure on substantially the entire surface of both the bottom surface and the slope, it is possible to configure a drainage flow channel, an air flow channel, and a gas vent flow channel on a wider surface, and as a result. This is a preferable laying method because it can dramatically reduce the possibility of clogging over time due to waste.
In addition, if the slope of the slope is very steep and nearly vertical, the geocell structure can be laid only on the bottom surface according to the structural requirements of the disposal site. It can be laid on a part of the slope or only on the slope.

  As described above, the geocell structure facilitates gap ratio management during crushed stone compaction while allowing leachate, air, and gas to pass in almost all directions, and has an excellent roadbed reinforcing effect. This makes it possible to provide a crushed stone or chestnut layer that is highly resistant to changes in the ground under the water-impervious sheet due to an earthquake or the like.

The present invention also relates to a waste final disposal site manufactured by the construction method described above.
FIG. 4 shows a cross-sectional view of a waste final disposal site where a geocell structure is laid.
As shown in FIG. 4, a geocell structure is laid on substantially the entire surface of the water-impervious sheet laid on substantially the entire bottom surface and slope, and crushed stone or chestnut is filled and compacted in the cell. A geocell structure layer in which chestnuts are sealed is formed.
Such a geocell structure layer has a function of collecting and draining leachate from the final waste generated by precipitation, a function as an air flow path required for decomposition of the final waste by aerobic microorganisms, and a final It can also have a function as a degassing flow path generated from waste.

  The construction method according to the present invention can be suitably used for a waste final disposal site having a landfill structure having a bottom surface and a slope.

1 slope 2 bottom 3 impermeable sheet 4 cushioning material 5 geocell structure layer 6 crushed stone or chestnut 7 water collecting pit (broken line)

Claims (7)

A construction method for a final disposal site with a landfill structure with a bottom and a slope, with the following steps:
The surface of a plurality of strip-shaped strips made of synthetic resin provided with a plurality of openings on substantially the entire surface of the water shielding sheet laid on substantially the entire bottom surface and / or slope, Laying flexible geocell structures that are joined together to form a plurality of cells alternately spaced apart in parallel when pulled away from the plane; and crushed stone and Filling / consolidating chestnut stone to form a geocell structure layer filled with the crushed stone or chestnut;
Including
Here, in the geocell structure layer, a function of collecting and draining leachate from the final waste generated by precipitation, and a function as an air flow path required for the decomposition of the final waste by aerobic microorganisms, The building construction method characterized by having a function as a degassing flow path generated from the final waste.   The construction method according to claim 1, wherein the synthetic resin is high-density polyethylene (HDPE).   The construction method according to claim 1 or 2, wherein a particle size of the crushed stone is 20 mm to 40 mm.   The construction method according to any one of claims 1 to 3, wherein the chestnut has a particle size of 5 to 15 cm. The thickness of the di can press structure layer is 100 to 200 mm, construction methods according to any one of claims 1 to 4.   The construction method according to any one of claims 1 to 5, wherein the geocell structure layer is stacked and stacked on a part of the water shielding sheet.   The waste final disposal site manufactured by the construction method according to any one of claims 1 to 6.

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