JP6734604B1 - Mass treatment method for ton bags containing high and low level radioactive waste. - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a flexible container bag containing earth and sand, which is a low-level radioactive waste, as a landfill material to construct an artificial island. PROBLEM TO BE SOLVED: To provide a method for mass treating a ton bag containing high-level or low-level radioactive waste capable of providing ground in a wide area and a method for confining radiation by placing concrete. 21 is separated from the open sea 11, and a large number of lumps 31 containing earth and sand, which are low-level radioactive waste, are placed in contact with each other in the island formation area 21, and mixed for cement-solidifying soil containing soil and cement components. The slurry is introduced between the lumps 31, and the mixed slurry for cement-solidifying soil is solidified to fill the gap between the lumps 31 with the cement-solidifying soil 33 to form the ground. [Selection diagram] Figure 2

Description

The present invention relates to a method for mass treating ton bags containing high-level and low-level radioactive waste for treating radioactive waste and a method for containing radiation by placing concrete.

Japan is known as a country with frequent earthquakes, and in particular, the Great East Japan Earthquake, which caused enormous damage to the Tohoku region, suffered immeasurable damage due to the tsunami and also caused an accident in which the nuclear reactor of the Fukushima nuclear power plant was damaged. I was hit. A large amount of radioactive materials released in the form of aerosols spread over a wide area in the form of aerosols and deposited and deposited on the ground due to rainfall, resulting in a large impact on the living environment of local residents.

Against this background, the Act on Special Measures Against Radioactive Material Pollution has been implemented, and so-called decontamination measures such as removal of soil with radioactive materials deposited, vegetation, debris, etc. have been earnestly promoted. Although decontamination measures are indispensable for reducing the exposure risk in the region, there are a number of challenges in these decontamination measures. In particular, it is a very important issue that the disposal place such as temporary storage, intermediate storage and final disposal of the waste contaminated with radioactive material is not yet secured. This is because securing a disposal site for decontamination waste generated by decontamination becomes a bottleneck, and decontamination measures are not proceeding as expected.

Decontamination measures are still underway, even though temporary storage sites are not sufficiently secured, and as a result, the generated soil and radioactive waste such as plants and debris were provisionally secured, for example, in the gardens of private houses. The reality is that they are stored in temporary storage.

Therefore, the invention described in Patent Document 1 discloses a disposal site for disposing a large amount of radioactive waste.
According to the invention described in Patent Document 1, a storage space for radioactive waste is formed in the ground beneath the coastal seabed, and a hole having seawater flowability in the vertical direction is formed in the ground between the storage space and the seaside land. A radioactive waste disposal site has been proposed in which a plurality of perforations are formed so as to intersect the saltwater groundwater flow, each hole is provided with a shape-retaining material, and seawater introduction means is provided above each hole. ..

JP-A-5-203797

However, in consideration of the fact that the formation of a storage space for radioactive waste in the ground below the coastal seabed is very costly and there is a risk of being opposed by residents and fisheries workers in the coastal area, such disposal Building a place is difficult.

Therefore, in the present invention, a large amount of ton bags containing the high-level or low-level radioactive waste generated by the decontamination measures are stored in the artificial island, so that a large amount can be processed at one time. in addition, an object of subjecting Hisage a mass treatment method ton bags containing the sediment is radioactive waste high level or low level to prevent the radioactive contamination due to leakage of radiation from the radioactive waste.

In order to achieve the above-mentioned object, the method for mass-processing ton bags containing high-level and low-level radioactive waste of the present invention divides the island formation area from the open sea by a dike, and the high level or low level is set in the island formation area. A large number of lumps made of ton bags containing earth and sand that are level radioactive waste are placed in contact with each other, and a cement-solidifying soil mixed slurry containing soil and cement components is introduced between the lumps, It is characterized by solidifying the mixed slurry for cement-solidifying soil to fill the gap between the lumps with the cement-solidifying soil, and placing concrete on the upper surface of the lumps to form concrete ground.

Further, a method for mass-processing a ton bag containing high-level and low-level radioactive waste of the present invention is formed by arranging a large number of the lumps and introducing and solidifying the mixed slurry for cement-solidifying soil into the gap. The feature is that the ground is constructed by laminating a plurality of accumulated layers.

In addition, the method for mass-processing ton bags containing high-level and low-level radioactive waste of the present invention provides a landfill foundation that is buried up to a position higher than the sea level of the open sea in the island creation area, and The mass treatment method for a ton bag containing high-level and low-level radioactive waste according to claim 1 or 2, wherein the lumps are arranged in the container and the mixed slurry for cement-solidifying soil is introduced and solidified. ..

Further, the method for mass-processing ton bags containing high-level and low-level radioactive waste according to the present invention is characterized in that a flexible container bag containing soil is arranged as at least a part of the lump.

According to the method for mass-processing ton bags containing high-level or low-level radioactive waste of the present invention, earth and sand which are high-level or low-level radioactive waste arranged in contact with each other in an island formation area are stored. A large number of lumps are filled with cement-solidifying soil by introducing the mixed slurry for cement-solidifying soil into the gaps between the lumps to solidify. Therefore, it is possible to treat a large amount of earth and sand, which is low-level radioactive waste.

In the mass treatment method for ton bags containing high-level or low-level radioactive waste of the present invention, a large number of lumps are arranged and a mixed slurry for cement-solidifying soil is introduced into the gap to stack a plurality of solidified sedimentary layers. When the ground is constructed, the mixed slurry for cement-solidifying soil can be surely introduced into the gaps of the lumps for each sedimentary layer, and the gaps of the lumps can be surely filled with the cement-solidifying soil for each sedimentary layer. Therefore, a stronger ground can be created.

In the mass treatment method for ton bags containing high-level or low-level radioactive waste according to the present invention, a landfill foundation that is landfilled to a position higher than the sea level of the open sea is provided in the island creation area, and a lump is formed on this landfill foundation. If the mixed slurry for cement-solidified soil is placed and solidified by arranging it, seawater does not exist in the gaps between many aggregates at the time of island formation, and the mixed slurry for cement-solidified soil can be reliably introduced between the aggregates, In addition, the mixed slurry for cement-solidified soil will not be dispersed or flowed out in seawater. Therefore, a sufficient amount of the mixed slurry for cement-solidifying soil can be introduced into the spaces between the agglomerates and solidified, and a sufficient amount of the cement-solidifying soil can be filled between a large number of agglomerates to form a more stable ground.
In addition, after the island is formed, it is possible to prevent the lumps and cement-solidified soil from being eroded by seawater, and to prevent these components from being eluted or dispersed in seawater, so that the ground can be stably maintained for a long period of time.

In the mass treatment method for ton bags containing high-level or low-level radioactive waste of the present invention, if a flexible container bag containing soil is arranged as at least a part of the lumps, the outer periphery of each lump will be a landfill foundation or. When it comes into contact with the surrounding lumps, it can be deformed to some extent, and the installation surface and the contact surface can be made wider to allow a large number of lumps to be densely arranged in a more stable manner, and a more stable ground can be constructed.
In addition, since the lumps are placed on the landfill foundation, it is possible to prevent the flexible container bag containing soil from contacting seawater during or after island formation, and the soil or its components contained in the flexible container bag can be placed in seawater. It does not flow out and can maintain a stable ground for a long time.

FIG. 1A is a diagram showing the configuration of the artificial island according to the present embodiment, and FIG. 1B is a diagram showing the size of the artificial island. It is the figure which showed the structure of the embankment vicinity of the artificial island which concerns on this embodiment. It is a figure showing a construction procedure of an artificial island concerning this embodiment. It is a figure showing a construction procedure of an artificial island concerning this embodiment. It is a completed drawing of the artificial island which concerns on this embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the present embodiment, a method of disposing the earth and sand which is a high-level or low-level radioactive waste will be described as an example of using this earth-and-sand to construct an artificial island.
The disposal facility 10 for high-level or low-level radioactive waste of this embodiment is an artificial island 13 surrounded by an open sea 11, as shown in FIG. A ground 15 having a predetermined structure is formed on the artificial island 13, and a runway 17 is provided on the ground 15. The artificial island 13 is further provided with a beach 19, a living area and a resort area (not shown).
FIG. 1B shows a configuration diagram showing the actual size of the artificial island.

The artificial island 13 of the present embodiment is formed in an area near the shallows and coral reefs in the sea away from land, and as shown in FIGS. 1 and 2, the artificial island 13 partitions the island formation area 21 from the open sea 11. A bank 23, a landfill foundation 25 that is landfilled in the island formation area 21 to a position higher than the sea surface 11a of the open sea 11, and a plurality of stacked layers 27 provided on the landfill foundation 25 in the island formation area 21. And a plurality of deposition layers 27 are stacked on the landfill foundation 25 to form the concrete ground 15.

The embankment 23 is formed around the outside of the island formation area 21 in the sea. The levee 23 may be continuously provided in an annular shape around the outer periphery, but if there is a part that is higher than the sea surface 11a in the natural state, the levee 23 may be provided continuously to the part. Good.

The embankment 23 may be constructed as a concrete structure, but in the present embodiment, it is constructed by utilizing concrete waste material and appropriately using gabion, rock, and the like. In this embankment 23, large concrete waste materials are deposited on the open sea 11 side and small concrete waste materials are deposited inside the island formation area 21, and the concrete waste materials are integrated by cement.
In this embodiment, the bank 23 and the island formation area 21 inside the bank 23 are continuously formed without a clear partition. A large number of tetrapots 29 and the like are arranged adjacent to each other on the open sea 11 side of the embankment 23.

The landfill foundation 25 is constructed almost entirely within the island formation area 21. The landfill foundation 25 is configured by stacking a large number of water resistant materials such as rocks, concrete waste materials, and gabions, and the upper surface thereof is provided at a position higher than the sea surface 11 a of the open sea 11.

The sedimentary layer 27 has a structure in which a large number of agglomerates 31 are arranged in contact with each other on the landfill foundation 25 in the island formation area 21, and cement-solidified soil as a filler is filled in a gap between the agglomerates 31 adjacent to each other. 33 is filled and buried. A plurality of stacked layers 27 are stacked on top of each other, and cement solidified soil 33 as a filler is interposed between the lumps 31 arranged vertically and in the gaps between lumps 31 adjacent to each other in the vertical direction. Good.

The lumps 31 can be appropriately used as long as they are members that can secure sufficient compressive strength, but in the present embodiment, at least a part of the lumps 31, preferably the majority or all, are soils called ton bags. It is composed of a flexible container bag that accommodates.

Each flexible container bag is formed into a bag shape with a resin sheet material having sufficient water resistance, etc., and is a member that can be tightly wrapped in a liquid-tight manner around the entire circumference in a state of containing soil inside. is there.
In the present embodiment, the soil contained in each flexible container bag contains earth and sand which are high-level or low-level radioactive waste generated by the decontamination work.
Since the lumps 31 have less variation in outer dimensions than rocks, concrete waste materials, or the like, in the present embodiment, it is easy to form the deposition layer 27 for each lump 31 arranged above and below.

Further, in order to form the deposition layer 27, a large amount of this lump 31 is used. That is, it is possible to process a large amount of earth and sand which are high-level or low-level radioactive waste contained in the lumps 31.

On the other hand, the filler that fills the gaps between the many lumps 31 is made of cement-solidified soil 33. The cement-solidified soil 33 is obtained by solidifying a mixed slurry for cement-solidified soil 33X containing a large amount of soil and a cement component, and is referred to as mud concrete, fluidized soil, cement-solidified soil, etc. It is a structural material in which the soil is solidified with the hardening reaction of. As the soil of the cement-solidified soil 33, cohesive soil such as Arakida soil can be particularly preferably used.
By this cement-solidified soil 33, it is possible to improve the strength of the deposited layer 27 in which a large number of lumps 31 are arranged and to improve the waterproof property.

In this embodiment, a deposit layer 27 including a large number of aggregates 31 and cement-solidified soil 33 is formed on the landfill foundation 25. Then, the concrete ground 15 is constructed by placing concrete on the upper surface of the deposited layer 27.
A tide embankment 23b made of a concrete structure is provided on an upper part of the embankment main body 23a formed by stacking concrete waste materials, gabions, rocks and the like.
In addition, a concrete layer 17a and an asphalt layer 17b are provided above the concrete ground 15 to form a runway 17, and a management road 17c and a drainage ditch 18a. Further, a green zone 18b or the like may be provided.

Next, a method for constructing the artificial island 13 and the contaminated soil disposal facility 10 will be described.
In the artificial island 13 of the present embodiment, the embankment 23 partitions the island formation area 21 from the open sea 11, and the landfill foundation 25 is installed in the island formation area 21 to a position higher than the sea surface 11a of the open sea 11, and the landfill foundation 25 is provided. A ground layer 15 is constructed by stacking a large number of lumps 31 and a sedimentary layer 27 composed of cement-solidified soil 33 on the ground.

First, as shown in FIG. 3, an island formation area 21 is set in an area near the shoal or coral reef in the sea away from land, and a dike 23 is formed so as to partition the island formation area 21 from the open sea 11.
In this embodiment, the embankment 23 is constructed by utilizing concrete waste material or gabion. Here, concrete waste materials and gabions are sorted by size, large concrete waste materials and gabions are deposited on the open sea 11 side, small concrete waste materials are deposited inside the island formation area 21, and cement slurry is poured from the surface side to cast concrete. The waste material and the gabion are connected, and the whole is fixed to form a concrete wall.

Next, as shown in FIG. 3, after the island formation area 21 is separated from the open sea 11 by the levee 23, a large number of water resistant materials such as rocks, concrete waste materials, and gabions are stacked in the island formation area 21 to arrange the open sea. The landfill foundation 25 is provided by landfilling to a position higher than the sea surface 11a of 11.

Next, as shown in FIG. 4, in the area where the landfill foundation 25 has been built up to a predetermined height, a plurality of deposition layers 27 including a large number of aggregates 31 and cement-solidified soil 33 are laminated on the landfill foundation 25. Each deposition layer 27 is composed of one to several stages of lumps 31 in the vertical direction and cement-solidified soil 33 filling the gaps between the lumps 31.

In order to form each deposition layer 27, a large number of lumps 31 are brought into contact with each other in a substantially horizontal direction, preferably arranged side by side, and at each stage, cement is provided between lumps 31 adjacent to or close to each other or in a gap. It is formed by introducing the mixed slurry for solidified soil 33X and solidifying it. In the present embodiment, the cement-solidifying soil mixed slurry 33X may be introduced and solidified between the lumps 31 that are laterally adjacent to each other or between the lumps 31 that are vertically adjacent to each other.
In the present embodiment, the above-mentioned flexible container bag in which contaminated soil is contained as soil as described above is used for part or all of the lumps 31.

On the other hand, the cement-solidified soil mixed slurry 33X is a slurry before solidification for obtaining the cement-solidified soil 33 containing soil and a cement component as described above, and in the present embodiment, preferably the viscosity of Arakida soil or the like. It is a slurry using soil. This slurry contains, as essential components, soil, cement components, and water, and is kneaded to such an extent that it has fluidity, with aggregates and other substances appropriately contained.

When this mixed slurry for cement-solidified soil 33X is introduced into the gaps between a large number of lumps 31 and solidified, the mixed slurry for cement-solidified soil 33X solidifies the soil and other mixtures in the slurry by hardening the cement component. It becomes the cement-solidified soil 33.
The cement-solidified soil 33 fills the gaps between the lumps 31 and the lumps 31 adjacent to each other are joined to each other, thereby forming a deposition layer 27 in which a large number of lumps 31 and the cement-solidified soil 33 are integrated. It

In this way, the artificial island 13 is constructed by stacking the sedimentary layer 27 on the landfill foundation 25 and forming concrete on the upper surface of the pile 27 to form the concrete ground 15.
Here, the concrete ground 15 is formed on the upper surface of the deposition layer 27 with a thickness of 5 to 20 cm.
In other words, by forming the concrete ground 15 having a thickness capable of containing the radiation on the upper surface of the deposition layer 27 so as to cover the radiation, it is possible to contain the radiation leaked from the lumps 31 forming the deposition layer 27. ..
Then, as shown in FIG. 5, a concrete layer 17a and an asphalt layer 17b are provided on the upper surface of the concrete ground 15 of the artificial island 13 to provide a runway 17, a management road 17c, a drain groove 18a, a green zone 18b, and the like. Then, the disposal facility 10 for contaminated soil using the artificial island 13 can be constructed.

According to the method for large-scale treatment of earth and sand as high-level or low-level radioactive waste according to the present embodiment as described above, a large number of lumps 31 (the above-mentioned earth and sand are (Stored) is mixed with the cement-solidifying soil 33X by introducing the mixed slurry for cement-solidifying soil 33X into the gaps between the lumps 31 and filling with the cement-solidifying soil 33.
Therefore, it is possible to treat a large amount of earth and sand, which is a high-level or low-level radioactive waste, by using a large number of lumps 31, and join a large number of lumps 31 with the strength of the cement-solidified soil 33. Therefore, it is possible to construct the artificial island by providing the stable concrete ground 15 in a wide area while securing the strength and securing the strength.

Further, according to the present embodiment, a large number of lumps 31 are arranged and a plurality of the sedimentation layers 27 solidified by introducing the mixed slurry for cement-solidifying soil 33X into the gaps are laminated, and concrete is poured to form the sedimentation layers 27. A concrete ground 15 is formed on the upper surface of the.
Therefore, the mixed slurry for cement-solidified soil 33X can be surely introduced into the gaps of the lumps 31 in each sedimentary layer 27, and the gaps of the lumps 31 of each sedimentary layer 27 can be surely filled with the cement-solidified soil 33 to strengthen the solidified soils. The deposit layer 27 can be formed, and concrete is poured so as to cover the top surface of the deposit layer 27 to form the concrete ground 15 having a thickness of about 5 to 20 cm.
This makes it possible to prevent radiation from leaking from the lumps 31 forming the deposition layer 27.

Further, according to the present embodiment, a landfill foundation 25 that is landfilled up to a position higher than the sea surface 11a of the open sea 11 is provided in the island creation area 21, and the lumps 31 are arranged on the landfill foundation 25 for cement-solidified soil. The mixed slurry 33X is introduced and solidified.
Therefore, at the time of island formation, seawater does not exist in the gaps between the many lumps 31, and the cement-solidified soil mixed slurry 33X can be reliably introduced between the lumps 31, and the cement-solidified soil mixed slurry 33X is dispersed in the seawater. , Never leaked. As a result, a sufficient amount of the cement-solidifying soil mixed slurry 33X can be introduced into the spaces between the lumps 31 and solidified, and a more stable ground 15 can be formed.
In addition, since the lumps 31 and the cement-solidified soil 33 are not eroded by seawater after the island is formed, it is possible to prevent radioactive substances from being eluted or dispersed from the earth and sand contained in the lumps 31. Besides, the ground 15 can be stably maintained for a long period of time.

In the method for creating the artificial island 13 of the present embodiment, the flexible container bag containing the soil is arranged as the lump body 31. Therefore, when the outer periphery of each lump 31 comes into contact with the landfill foundation 25 and the surrounding lumps 31, it can be deformed to some extent. As a result, the installation surface and the contact surface of each lump 31 can be made wider, and a large number of lumps 31 can be densely arranged in a more stable manner, and a more stable ground 15 can be created.

Further, since the lumps 31 are arranged on the landfill foundation 25, it is possible to prevent the flexible container bag containing soil from coming into contact with seawater at the time of island formation or after that, and radioactive materials from the earth and sand contained in the flexible container bag are converted to seawater. It is possible to keep the ground 15 stable for a long period of time without flowing into the ground.

Further, according to the artificial island 13 of the present embodiment thus constructed, the landfill foundation 25 is provided in the island formation area 21 to a position higher than the sea surface 11a of the open sea 11, and the landfill foundation 25 is provided on the landfill foundation 25. A large number of lumps 31 are arranged in contact with each other and the gaps between the lumps 31 are filled with cement-solidified soil 33.
Therefore, it is possible to prevent the lumps 31 and the cement-solidified soil 33 from coming into contact with seawater and being eroded, and the components thereof from being eluted or dispersed in seawater. As a result, the large number of lumps 31 and the cement-solidified soil 33 filled between the lumps 31 make the ground 15 stable over a wide area while ensuring sufficient strength, and can be kept stable for a long period of time. 15 can be provided.

In particular, in the artificial island 13 of the present embodiment, at least a part of the many lumps 31 is made of a flexible container bag containing soil. Therefore, when the outer periphery of the lump 31 comes into contact with the landfill foundation 25 and the lumps 31 around it, the lump 31 can be deformed to some extent. As a result, the installation surface and the contact surface can be made wider, and a large number of lumps 31 can be more stably and densely arranged, and a more stable ground 15 can be secured.
Further, since the lumps 31 are arranged on the landfill foundation 25, it is possible to prevent the flexible container bag containing the soil from coming into contact with seawater, and the soil or its components contained in the flexible container bag may flow out into the seawater. Therefore, it is possible to maintain the stable concrete ground 15 for a long time.

If the artificial island 13 of the present embodiment is used as the earth and sand disposal facility 10 for low-level radioactive waste as described above, a flexible container bag containing this earth and sand is used as the lumps 31 for landfill foundation 25. It is arranged on the upper side, and the cement solidified soil 33 is filled in the gap to stabilize the concrete ground 15 and the runway is provided on the ground 15. Therefore, a runway can be provided on the concrete ground 15 having sufficient strength and stable, and low level radioactive material can be isolated from the surrounding environment and stably maintained or disposed for a long period of time. It is possible.

The above embodiment can be appropriately modified within the scope of the present invention.
For example, in the above-described embodiment, since the flexible container bag containing the soil as the lumps 31 is used, the variability in the size of each lump 31 is small, and therefore, a plurality of deposition layers 27 are stacked on the landfill foundation 25 to form a ground. Although 15 is formed, it does not have to be a structure in which a plurality of piled layers 27 are stacked in layers on the landfill foundation 25, for example, a structure in which lumps 31 are randomly arranged and fixed by cement solidified soil 33. May be.

Further, in the above embodiment, the landfill foundation 25 is constructed after the entire circumference of the island construction area 21 is partitioned by the embankment 23, but the invention is not particularly limited. For example, after partitioning at least a part of the island creation area 21 by the embankment 23, the landfill foundation 25 can be appropriately created from the area where construction can be performed.

10 Disposal Facility 11 Open Sea 11a Sea Surface 13 Artificial Island 15 Concrete Ground 17 Runway 17a Concrete Layer 17b Asphalt Layer 17c Management Road 18a Drain 18b Green Zone 19 Sandy Beach 21 Island Creation Area 23 Levee 23a Levee Main Body 23b Tidal Levee 25 Landfill Foundation 27 Deposition Layer 29 Tetrapot 31 Agglomerate 33 Cement solidified soil 33X Cement solidified soil mixed slurry

Claims (4)

The embankment divides the island development area from the open sea ,
Arranging a large number of lumps made of ton bags containing earth and sand, which are high-level or low-level radioactive waste, in contact with each other in the island creation area,
Introducing a mixed slurry for cement-solidifying soil containing soil and cement components between the agglomerates,
Filling the gap between the lumps with the cement-solidifying soil by solidifying the mixed slurry for cement-solidifying soil,
A method for mass-processing a ton bag containing high-level and low-level radioactive waste, characterized by forming concrete on the upper surface of the lump to form concrete ground. The ground according to claim 1, wherein a plurality of the agglomerates are arranged and a plurality of sedimentary layers formed by introducing and solidifying the cement-solidifying soil mixed slurry into the gap are laminated to form a ground. High-volume disposal method for ton bags containing low-level and low-level radioactive waste. A landfill foundation that is landfilled to a position higher than the sea level of the open sea is provided in the island creation area, and the lumps are arranged on the landfill foundation to introduce and solidify the mixed slurry for cement-solidifying soil. The method for mass-processing ton bags containing high-level and low-level radioactive waste according to claim 1 or 2. The method of mass treating ton bags containing high-level and low-level radioactive waste according to claim 3, wherein a flexible container bag containing soil is arranged as at least a part of the lumps.

Images