JP2016007562A - Waste volume reduction treatment method in landfill waste disposal site - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waste volume reduction treatment method where a volume reduction treatment can be performed even in a waste disposal site capable of not maintaining a compaction hole in a landfill and the like since the volume reduction treatment method of the waste disposal site that excavated waste as it is is compacted to a pore wall to form a non-discharge excavated hole (compaction hole) and surface layer refuse and transported refuse are charged into the compaction hole is hardly performed in a landfill waste disposal site in which a hydrous laminate waste layer A exists.SOLUTION: In a waste volume reduction treatment method, a volume reduction treatment step where a new waste disposal space consisting of a non-discharge excavated hole D is formed and a surface layer waste E is charged is performed after a drain compaction step where a drain material is installed in the volume reduction object range of a laminate waste in a landfill waste disposal site and seepage water in a hydrous laminate waste layer A is compacted to a non-hydrous laminate waste layer B by performing forced discharge due to vacuum suction.

Description

  The present invention relates to a waste volume reduction processing method that realizes volume reduction of waste (expansion of waste space) in a landfill waste disposal site.

  Waste that is not reused, such as general waste and industrial waste, is dumped in the waste disposal site, and dumping is simply performed on the previous waste, and the waste is sequentially stacked. It is. If left unattended, there is no reduction in volume other than natural compression by its own weight. For this reason, when the disposal site is full, another disposal site must be found.

  Therefore, in the waste disposal site, using the excavated earth and sand compacted auger (excavated body) with a trowel on the outer periphery, excavating and drilling without discharge to form a consolidated hole (non-excavated excavation hole), the consolidation There is known a waste treatment method in which a waste waste space is newly formed by holes and waste is filled in the space.

  For example, in Patent Document 1 (Japanese Patent Application Laid-Open No. 10-272432), after forming a consolidation hole, waste is thrown in from the hole opening while the excavation body is inserted into the hole and rotated backward and pulled out. A means is disclosed in which a hole portion (consolidation plate) is pressed against a hole wall while dropping to the bottom, and the remainder is sequentially deposited on the hole bottom.

  Patent Document 2 (Japanese Patent Laid-Open No. 2001-286843) discloses a excavation comprising a casing provided with a consolidation trowel (consolidation plate) on the peripheral surface and a drill rod having a drill head passing through the casing and protruding from the tip. A waste processing method is disclosed in which a body is used, non-discharge excavation is performed with a compacting trowel of the casing, surface layer waste is put into the casing with the casing remaining, and the casing is later pulled out.

  In Patent Document 3 (Japanese Patent Application Laid-Open No. 2006-15262), after forming an exhaustless compaction hole and pulling out the auger, a casing having a smooth outer peripheral surface is set up in the compaction hole, and waste is charged into the casing. However, a processing method is disclosed in which the casing is pulled out after filling.

  Further, Patent Document 4 (Japanese Patent Application Laid-Open No. 2008-302273) discloses a drilling head in which an inverted frustoconical drilling part is provided at the tip of a cylindrical body provided with a consolidation iron part, and a continuous connection with the drilling head. A waste treatment method is disclosed in which a compact hole is formed and held with the casing and the excavation member is pulled out, and then waste is put into the compact hole.

Japanese Patent Laid-Open No. 10-272432. JP 2001-286843 A. JP 2006-15262 A. JP 2008-302273 A.

  By the way, the landfills of coasts and lakes are often made up of dredged materials such as dredged sand, construction waste and incineration ash at the time of reclamation, and the landfill board itself is not precise. In addition, seawater and lake water permeate into sedimentary waste at low places below sea level and lake level, and water and waste are saturated. Further, in the case of dredged sand, building waste, incineration ash, etc., in which waste is frequently used in landfills, the moisture content is high even on the water surface.

  In such a waste disposal site, a previously known volume reduction processing method of digging a consolidation hole to secure a new waste space and throwing waste into the consolidation hole is applied as it is, Since waste and water are saturated, it is difficult for new waste to form a space. In addition, waste such as incinerated ash containing a large amount of water is mud by agitation during excavation, and it is difficult to construct a consolidation hole. For this reason, for example, even if the construction method described in Patent Document 1 is adopted in a landfill, the hole wall of the consolidation hole is not retained by the casing, and therefore, the hole wall of the consolidation hole collapses at the time of waste charging operation.

  Further, in the method of putting the casing into the consolidation hole after forming the consolidation hole as in the construction method described in Patent Document 3, the consolidation hole collapses before the casing is installed. As in the construction method described in Patent Document 4, a method based on the premise of maintaining the shape of the compacted hole itself by pulling out the excavated body is not realized due to the collapse of the compacted hole.

  Further, as in the waste treatment method described in Patent Document 2, the means for throwing waste while leaving the casing can cope with the collapse of the hole wall of the excavation hole in the non-discharge excavation work. As a result of the inflow of waste, etc., intrusion of waste also occurs, and it is not always efficient to secure a new waste space.

  Therefore, the present invention proposes a novel waste volume reduction processing method in a landfill waste disposal site.

  The waste volume reduction processing method in the landfill waste disposal site according to claim 1 of the present invention is a drainage consolidation step of draining the volume reduction target range of the laminated waste in the landfill waste disposal site, A volume reduction process step is performed in which a no-discharge hole is excavated and waste is introduced into the no-discharge hole.

  Therefore, the waste volume reduction treatment method is appropriately applied to a sediment waste layer including an old seabed stratum (old lake bottom) and a water-containing waste layer above the water surface at a landfill waste disposal site. Draining by applying a simple construction method (various construction methods known as soft ground improvement technology) will eliminate the cause of hindrance to the formation of no-discharge holes, and volume reduction due to excavation of no-discharge holes It is possible.

  Further, in the waste volume reduction processing method according to claim 2 of the present invention, in particular, the drainage compaction process places a drain material in the volume reduction target range and forces the permeated water in the laminated waste by vacuum suction. Exhaust water (including soft ground pore water) is forcibly removed by vacuum suction together with waste interstitial air, and forcible compaction is performed together with drainage of the sediment waste layer. It is made to be able to effectively build.

  Further, in the waste volume reduction processing method according to claim 3 of the present invention, in the vacuum suction, the area where the drain material is placed is sealed with an airtight sheet to be shut off from the outside air, and connected to an intake pump under the airtight sheet. In addition, a perforated pipe connected to the drain material is disposed, and the bottom of the airtight sheet is set in a negative pressure state so that the permeated water in the laminated waste is discharged to the surface and drained.

  In other words, a vertical drain material with aeration water permeability is buried in buried waste to a predetermined depth at an appropriate interval, and the top of the placed vertical drain material is connected with a horizontal drain material with aeration permeability. At the same time, the perforated pipe is connected to the horizontal drain material and piped, and the whole is covered with an airtight sheet and the end of the sheet is embedded to block the volume reduction target surface of the disposal site where the drain material is constructed from outside air. .

  In the above state, when connected to the perforated pipe and the intake pump through the air / water separation tank (the upper part is connected to the intake pump and the lower part is connected to the drainage pump), and the intake pump is driven, Under the hermetic sheet, negative pressure (vacuum pressure) is generated, and the permeated water present in the gap between the stacked wastes is sucked up to the surface through the vertical drain material together with the gap air, and from the inside of the perforated pipe to the air-water separation tank through the horizontal drain. Enter and drain water.

  Therefore, the continuous operation of the intake pump eliminates osmotic water and interstitial air in the laminated waste in the volume reduction target range and settles and compresses by its own weight, so that the hydrated laminated waste layer becomes a consolidated state of the non-hydrated laminated waste layer. Therefore, a new waste space is formed by a known non-discharge perforation (consolidation hole), and waste is filled in the space to realize volume reduction of waste at the disposal site.

  As described above, the construction method of the present invention can realize a reliable volume reduction of the laminated waste at the landfill disposal site.

Process explanatory drawing (state before construction) of embodiment of this invention construction method. The same (drainage compaction process). Same as above (state after wastewater compaction process). Same (start of volume reduction process). Same as above (in the middle of volume reduction process). Same (the final stage of the volume reduction process). Explanatory drawing which shows another example of the volume reduction process of this invention construction method.

  Next, an embodiment of the method of the present invention will be described. The method of the present invention comprises a drainage consolidation process and a volume reduction process. The target is a waste disposal site formed in a landfill.

  The landfill site is often disposed of with waste such as dredged sand, building waste, and incinerated ash when landfilled, and various miscellaneous wastes such as plastic waste are often dumped. In such a disposal site, the laminated waste is gradually consolidated by its own weight, but the seawater / lake C is penetrating into the sediment waste at sea level or at a low level below the lake level. On the soft wet sediment waste layer A that is in a state of hand, there is a laminated waste layer B that is somewhat compacted by its own weight.

  In the present invention, a drainage compaction process is performed as a pretreatment for performing a volume reduction process on the waste disposal site as described above. The volume reduction treatment method is a method for reducing the volume of waste in a desired area by constructing a predetermined construction method with an appropriate range as a volume reduction target range in a vast landfill disposal site and changing the range sequentially.

  The drainage consolidation process employs a known method in soft ground improvement work. Specifically, the vertical drain member 1 having water permeability and air permeability such as a hard fiber board and a perforated thin tube in a predetermined range is appropriately used with its head exposed on the surface of the laminated waste layer B. Place many at intervals.

  Next, while connecting the top part of the said vertical drain material 1 with the horizontal drain material 2, the perforated pipe | tube 3 is made to contact the said horizontal drain material 2, and piping. The entire area where the drain material 1 is placed and the perforated pipe 3 is piped is covered with the airtight sheet 4 and the end of the airtight sheet 4 is embedded to block the area from the outside air.

  Further, the perforated pipe 3 is a non-porous pipe connected to the air / water separation tank 5, the upper part of the air / water separation tank 5 is connected to the intake pump 6, and a drainage pump is built in the bottom of the air / water separation tank 5. It is what.

  The above-described appliances and devices are arranged to operate the intake pump 6. By the operation of the pump 6, the air on the lower surface of the airtight sheet 4 is sucked by the perforated pipe 3, and the space below the airtight sheet 4 is negative pressure Vacuum pressure). Furthermore, both the permeated water and the gap air existing in the gap between the laminated waste layers A and B are sucked up to the surface through the drain material 1 and sucked into the perforated tube 3 through the horizontal drain material 2 to Enter the water separation tank 5. The permeated water sucked in the steam / water separation tank 5 is stored in the tank and discharged to the outside by a drain pump (not shown).

  Accordingly, the permeated water contained in the water-containing laminated waste layer A in the volume reduction target range is eliminated by continuous operation of the intake pump 6, and when the permeated water is eliminated, the laminated waste is compressed together with the exclusion of interstitial air. In addition, it becomes a laminated waste layer B that does not contain osmotic water from the hydrated laminated waste layer A containing osmotic water. If left as it is, the compacted state is released by the restoration of the water-containing waste due to the permeation of the permeated water.However, since the permeation of seawater and lake water requires a corresponding amount of time, the following reduction immediately follows the drainage compaction process. The volume treatment process is performed.

  The volume reduction process is to form a new waste space with known discharge-free perforations (consolidation holes), and to reduce the volume of waste at the disposal site by discarding and filling the space with the waste. Excavator 7, excavator 8, hydraulic excavator 9, and crane device 10.

  The illustrated excavation body 7 employs a casing-shaped excavation body, and is provided with an excavation part 71 at the tip and a consolidation part 72 that presses the hole wall like a trowel following the excavation part 71. When this is reached, the additional casing 73 is linked and used.

  The excavation part 71 only needs to have a function capable of perforating the stacked waste layers A and B. The excavation part 71 includes a drilling blade for drilling while laminating the stacked waste layers A and B, or a conical shape. As an alternative, the laminated waste layers A and B may be screwed and perforated. The consolidation section 72 is provided with a plurality of multi-stage consolidation plates that gradually project in the outer peripheral direction corresponding to the rotation direction and have the maximum diameter matched with the diameter of the excavation hole.

  The excavator 8 is an existing device that is appropriately selected according to the desired excavator 7, such as an all-round rotating all-casing excavator (shown in FIGS. 4 to 6) and a three-point support pile driver (shown in FIG. 7). Thus, an excavation mechanism 81 that holds the excavation body 7 and performs rotary excavation is provided.

  The volume reduction process using the above-mentioned equipment consists of excavation work and backfilling work. The excavator attaches the excavation body 7 to the excavation mechanism 81 of the excavation device 8 and at the planned excavation position of the excavation hole D. Start drilling.

  The excavator digs into the stacked sediment layer B while rotating the excavated body 7 by the excavating mechanism 81, and further presses the waste against the hole wall with a compacting plate to form a compacted hole D having a predetermined depth. To do. This excavation hole D is formed by non-discharge excavation. In addition, when the excavated body 7 is added, as shown in FIG. 5, the crane apparatus 10 is used to add and the casing 73 is lifted.

  In the backfilling work, a hydraulic excavator 9 is used to throw in waste E collected from the top opening of the excavation hole D where the excavation body 7 is lifted up and the waste from the disposal site and the surface layer waste from the disposal site. To do. When charging the waste E, if the input waste F is filled with the weight 11 suspended by the crane device 10, a larger amount of the waste E can be input.

  If such excavation work and backfilling work are sequentially repeated while changing the excavation position, it becomes possible to dispose a larger amount of waste at a full waste disposal site.

  The method of the present invention is not limited to the above-described embodiment. For example, in the drainage compaction process, a drain pipe having a small through hole corresponding to a predetermined depth without using an airtight sheet as a vacuum suction means. (Drain material) is buried, the suction pump is connected via the top of the drain pipe and the air / water separation part, and the drain pipe is buried along with the vacuum drainage with a roller device, and heavy pressure is applied to force the laminating waste. Consolidation may be applied.

  Furthermore, in the drainage compaction process, well-known well points that partition the periphery of the volume reduction range with a sheet pile, etc., place a slit tube in the range, and have a drainage pump in the slit tube to drain the volume reduction range. You may employ | adopt the method of the well-known ground improvement construction method known as a construction method or a Davewell construction method.

  In the volume reduction process, the means for forming the no-discharge drilling hole is arbitrary. For example, as shown in FIG. 7, a pile driving machine 8a (excavation device) provided with a rotary pile driving mechanism 81a is provided with an excavation part 71a composed of a crushing bit at the tip and a consolidation plate 72a at the shaft part. A well-known technique for forming a no-discharge drilling hole may be employed.

A Water-containing layered waste layer B Non-water-containing layered waste layer C Seawater / Lake water D Drilling hole E Waste (surface layer waste)
F Input waste 1 Vertical drain material 2 Horizontal drain material 3 Perforated pipe 4 Airtight sheet 5 Air / water separation tank 6 Intake pump 7 Excavator 71 Excavator 72 Consolidator 73 Addition casing 7a Excavator drill 71a Excavator 72a Consolidation plate 8, 8a excavator 81 excavation mechanism 81a rotary pile driving mechanism 9 hydraulic excavator 10 crane apparatus 11 weight

Claims (4)

  After the drainage compaction process, which drains the volume of the stacked waste in the landfill waste disposal site, the volume reduction treatment process is conducted by drilling a no-discharge hole and throwing the waste into the no-discharge hole. Waste volume reduction treatment method at landfill waste disposal site, characterized by   The waste in the landfill waste disposal site according to claim 1, wherein the drainage compaction step is to place drainage material in the volume reduction target range and forcibly remove the permeated water in the laminated waste by vacuum suction. Volume reduction treatment method.   In the drainage compaction process, the area where the drain material is placed is sealed with an airtight sheet to shut off the outside air, and a perforated pipe connected to the intake pump and connected to the drain material is placed under the airtight sheet, The waste volume reduction processing method in a landfill waste disposal site according to claim 2, wherein the permeated water in the laminated waste is discharged to the surface as a negative pressure state and drained.   The volume reduction processing step uses an excavated body provided with a compacted portion provided with a plurality of compacted plates with the maximum diameter coinciding with the diameter of the excavated hole, gradually projecting toward the outer periphery corresponding to the excavated portion and the rotation direction at the tip. A landfill according to any one of claims 1 to 3, wherein a non-discharge drilling hole is formed, and one or both of surface waste and new waste existing in a disposal site are input and embedded in the non-discharge drilling hole. Waste volume reduction method at a local waste disposal site.

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