JP4488976B2 - Method and apparatus for solidifying radioactive waste - Google Patents

Description

  The present invention relates to a radioactive waste solidification method and apparatus for solidifying a waste having a high radionuclide concentration among radioactive waste generated from a nuclear facility.

  There are various types of radioactive waste generated from nuclear facilities. Generally, these are assumed to be cement solidified, glass solidified, melted solidified, and the like. Among these, since the cement solidification method is inexpensive and easy to process, application to solidification of many wastes is assumed.

  However, when the concentration of radionuclide contained in the radioactive waste is high, pore water, crystal water, and the like present in the cement solidified body are radiolyzed, and as a result, hydrogen gas and the like are assumed to be generated. In order to suppress the release of this gas from the solidified container, it is conceivable to seal the container, but there is a concern that the internal pressure will increase during long-term storage. In other words, it is assumed that the pressure inside the container will increase after the landfill disposal, which will affect the soundness of the disposal site.

  For this reason, France's COGEMA and SGN have installed a filter on the top of the container that holds the compressed body of the spent fuel cladding tube, which is a waste product with a high radionuclide concentration, so that the generated gas can be released. The use of CSD-C Universal Canister is under consideration. However, when such a filter is attached, there is a concern that tritium gas is generated and radioactive gas is released to the outside of the container if water containing tritium is present inside.

  In addition, a method of arranging a carbon dioxide fixing agent in a canister has been proposed (see, for example, Patent Document 1). In this case, if a factor such as the life of the fixed drug does not function normally, the possibility of causing a pressure increase cannot be denied.

In addition, a method of vacuum drying the inside of a radioactive waste drum can containing radioactive waste has been proposed (see, for example, Patent Document 2). However, in this method, the inside of the drum can containing the radioactive waste is vacuum-dried, and the solidified cement is not dried. Therefore, it is difficult to treat the liquid radioactive waste. Moreover, since radioactive waste is not fixed, there is a concern that the radioactive material may ooze out from the storage container. Furthermore, when the cement solidified body is dried by this method, the gap between the waste and between the waste and the drum can is filled with cement, so that the drying process is extremely difficult, and the amount of moisture generated by the drying process is large. For this reason, if it is discharged directly to the off-gas treatment system, condensation may occur in the off-gas treatment system, resulting in a decrease in function.
JP 2001-228296 A JP 2004-340814 A

  In the above-mentioned conventional solidification method for radioactive waste with high radioactivity concentration, among the radioactive waste generated from nuclear power plants, etc., solid waste with high radionuclide concentration is solidified with hydraulic inorganic solidification material such as cement. Then, hydrogen gas etc. generate | occur | produce by the radiolysis of water, and it may cause a pressure rise in a container, The method of suppressing this gas generation has not been established.

  Therefore, the present invention suppresses or prevents gas generation from the solidified material due to radiolysis during the embedding of the solidified material obtained by solidifying the radioactive waste with high radioactive concentration with the hydraulic inorganic solidified material, and the disposal for a long period of time. It is an object of the present invention to provide a radioactive waste solidification processing method and apparatus capable of suppressing or preventing an increase in pressure inside a storage container and ensuring soundness of a disposal site over a long period of time.

  In order to achieve the above object, the present invention provides a radioactive waste that solidifies radioactive waste having a radionuclide concentration high enough to generate gas by radioactive decomposition during buried disposal among radioactive waste generated from nuclear facilities. In the solidification method, the radioactive waste, the hydraulic inorganic solidified material, and the aggregate are kneaded and then supplied to a storage container to form a solidified body, and the solidification in the storage container After the body is cured, a moisture removal step for removing moisture from the solidified body in the storage container by heating and / or decompression, and a storage container for sealing the storage container with a lid after passing through the moisture removal step And a sealing step.

  In addition, in order to achieve the above object, the present invention provides a radioactive waste that solidifies radioactive waste having a high radionuclide concentration to the extent that radioactive waste generated from nuclear facilities is radioactively decomposed to generate gas during disposal. In the solidification processing apparatus, a storage container in which a solidified body containing the radioactive waste and the hydraulic inorganic solidified material is stored is stored, and moisture of the solidified body in the storage container is heated and / or reduced in pressure. Moisture removing device for removing, moisture separating means for removing moisture in off-gas generated by heating and / or decompression, and off-gas for removing radionuclides from the off-gas from which moisture has been removed by the moisture separating means And a processing means.

  According to the present invention, during the embedding of a solidified material obtained by solidifying a radioactive waste of high radioactive concentration with a hydraulic inorganic solidified material, gas generation from the solidified material due to radiolysis is suppressed or prevented, and long-term embedding disposal It is possible to provide a radioactive waste solidification processing method and apparatus capable of suppressing or preventing an increase in pressure inside the storage container and ensuring the soundness of the disposal site over a long period of time.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is a flowchart showing a procedure of a radioactive waste solidification method according to an embodiment of the present invention. As shown in FIG. 1, radioactive waste 1, hydraulic inorganic solidified material 2, aggregate 3 and water or the like as necessary are kneaded (S1a). The solidified paste is stored in a storage container (S1b). Is formed. At this time, it is also possible to knead in the storage container using an in-drum mixer or the like.

The radioactive waste 1 of the present invention is generated from a nuclear facility or the like, and has a high radioactivity concentration that is high in radionuclide concentration to the extent that radiolysis occurs during buried disposal and gas is generated from the solidified material. Say. The radioactive waste 1 may be solid or liquid, and examples thereof include high-concentration sodium sulfate waste liquid.
The hydraulic inorganic solidifying material 2 of the present invention solidifies the radioactive waste 1 and includes a cement-based solidifying material and the like. For example, various portland cements such as ordinary portland cement, early-strength portland cement, medium heat portland cement, low heat portland cement, various mixed cements such as blast furnace cement and fly ash cement, and various cements such as alumina cement can be used.

  As the aggregate 3, for example, sand, gravel, stone, alumina, silica fine powder, artificial lightweight aggregate, perlite, chamotte, iron powder, concrete waste, etc. can be used. By using aggregate as described later, it becomes easy to remove moisture from the formed solidified body by heating and / or decompression. Although the usage-amount of an aggregate is not specifically limited, 5-1500 weight part is preferable with respect to 100 weight part of hydraulic inorganic solidification materials (cement), and 100-1000 weight part is further more preferable. If the amount is less than 5 parts by weight, the effect of the aggregate that makes it easy to remove moisture from the formed solidified body by heating or the like is reduced, and if it exceeds 1500 parts by weight, strength development may be reduced.

In addition, various admixtures (materials) such as a fluidizing agent, a water reducing agent, an AE agent, and a high performance AE water reducing agent can be used as necessary.
The fluidizing agent is an additive added to improve the fluidity of the solidified paste, and examples thereof include inorganic fluidizing agents such as condensed sodium phosphate or a carbonate compound. These may be used alone or in combination of two or more. You may mix.

  After the solidified body formed in the storage container is sufficiently cured, the moisture is removed from the solidified body by heating and / or decompressing (S2). The off-gas 4 generated at this time is introduced into the off-gas treatment means (to be described later) and adsorbs the radio nuclides when it contains the radionuclide after the moisture in the off-gas 4 is removed by the moisture separation means (to be described later) (S3). It is removed by combustion or the like (S4).

The curing method is not particularly limited, and for example, any method such as air drying curing, wet air curing, heating accelerated curing (steam curing, etc.) may be adopted.
The heat treatment temperature is preferably 100 ° C. or higher and lower than 500 ° C. If it is lower than 100 ° C., the removal of moisture from the solidified body is insufficient, and if it is 500 ° C. or higher, calcium hydroxide in the solidified body is decomposed and the internal structure of the solidified body may be damaged. However, since alumina cement is mainly composed of calcium aluminate and has heat resistance, it is preferably 100 ° C. or higher and 1600 ° C. or lower.
The heat treatment time is preferably 8 hours or more and 20 hours or less. When the heat treatment time is less than 8 hours, the removal of moisture from the solidified body is insufficient, and when the heat treatment time is about 20 hours, the water removal amount is almost saturated. The effect of removing moisture by heating is reduced.

  The reduced pressure is preferably a treatment pressure of 0 kPa to 1 kPa. When it exceeds 1 kPa, the removal of moisture from the solidified body may be insufficient.

After the above solidified body is sufficiently heated and / or decompressed to remove moisture (S2), the storage container is covered and sealed (S5). The storage container is sealed by welding the outer periphery of the cover or by interposing a sealing material between the cover and the storage container. As a result, it is possible to prevent water from entering the storage container for a long time even after disposal.
The storage container storing the solidified body is covered and sealed, and then buried in the buried disposal facility (S6).

  In the present embodiment configured as described above, the radioactive waste 1, the hydraulic inorganic solidified material 2 and the aggregate 3 are kneaded to form a solidified body, and by sufficiently heating or the like to remove moisture, During the embedding of the solidified body, gas generation from the solidified body due to radiolysis can be suppressed or prevented.

  According to the present embodiment, since the gas generation from the solidified body can be suppressed or prevented by radiolysis during the embedding of the solidified body, even if the radioactive waste has a high radionuclide concentration, it is buried for a long period of time. An increase in pressure in the storage container during disposal can be suppressed or prevented, and the soundness of the disposal site can be secured over a long period of time.

(Second Embodiment)
This embodiment is different from the first embodiment in the following points. In this embodiment, a foaming agent (bubble agent) is supplied to the storage container instead of the aggregate 3 supplied together with the radioactive waste 1 and the hydraulic inorganic solidified material 2 or together with the aggregate 3.
The foaming agent (foaming agent) is used for forming voids in the solidified body and obtaining cellular concrete (or mortar or cement paste). For example, amphoteric metals such as metallic aluminum powder, surfactants, Animal proteins, resin soaps, and the like can be used, and amphoteric metals such as metal aluminum powder and surfactants are preferred because they are effective when added in small amounts. By using a foaming agent (bubble agent), it becomes easy to remove moisture from the formed solidified body by heating and / or decompression.

  Amphoteric metals such as metallic aluminum powder use gas generated by chemical reaction. Although the usage-amount of aluminum powder is not specifically limited, 0.01-0.4 weight part is preferable with respect to 100 weight part of hydraulic inorganic solidification materials (cement), and 0.05-0.3 weight part is further more preferable. . When the amount is less than 0.01 part by weight, the foaming amount is small, and the effect of adding a foaming agent that it is easy to remove moisture from the formed solidified body by heating or the like becomes small. May become smaller.

Examples of the surfactant include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant, which are excellent in foaming properties, stable in bubbles and large in fluidity. In terms, an anionic surfactant is preferred.
Examples of anionic surfactants include soaps such as sodium laurate and sodium stearate, sulfate esters such as sulfated oil and sulfated fatty acid esters, sulfonates such as alkylbenzene sulfonate and paraffin sulfonate, Examples include phosphate esters such as higher alcohol phosphates.
Although the usage-amount of an anionic surfactant is not specifically limited, 0.01-5 weight part is preferable with respect to 100 weight part of hydraulic inorganic solidification materials (cement), and 0.1-1 weight part is further more preferable. When the amount is less than 0.01 part by weight, the foaming amount is small, and the effect of adding a foaming agent that the moisture is easily removed from the formed solidified body by heating or the like is small. There is a case.

  In the other respects, the present embodiment is not fundamentally different from the first embodiment, and the description thereof will be omitted.

Next, a radioactive waste solidification processing apparatus according to an embodiment of the present invention will be described.
FIG. 2 is a diagram showing a configuration of a radioactive waste solidification processing apparatus according to an embodiment of the present invention. The radioactive waste solidification treatment device 10 includes a mixer 11, a storage container 12, a transfer device 13, a moisture removal device 14, a moisture separation means 15, an off-gas treatment means 16, and a sealing means (not shown). It is configured.

The mixer 11 mixes the solidified paste containing the radioactive waste 1 and the hydraulic inorganic solidified material 2 and functions as a mixing means. The mixer 11 is not specifically limited, For example, various mixers, such as an omni mixer, a bread-type mixer, a biaxial kneader mixer, can be used.
The storage container 12 stores the solidified paste mixed by the mixer 11 and is, for example, a drum can. For example, carbon steel, stainless steel, zirconium, titanium, copper, or the like can be used as a constituent material of the storage container 12. When the inside of the storage container 12 is vacuum-dried, it is preferable to use a pressure resistant container.
In addition, you may knead | mix in the storage container 12 using an in-drum mixer etc.

  The transfer device 13 transfers the storage container 12 in which the solidified paste (or solidified material) is stored to the moisture removing device 14, and is, for example, a belt conveyor. It can also be transferred by a forklift or the like.

The moisture removing device 14 accommodates the storage container 12 in which the solidified paste is stored, and after curing, removes the moisture of the solidified body in the storage container 12 by heating and / or depressurization. / Or provided with vacuum evacuation means.
A heating furnace is not specifically limited, For example, various heating furnaces, such as a resistance heating furnace and an induction heating furnace, can be used.
The vacuum exhaust means is not particularly limited, and for example, various vacuum pumps can be used.

  The moisture removal by the reduced pressure can be performed by the following method. In the first method, the storage container 12 is covered with a dedicated lid for vacuum drying, and the inside of the storage container 12 is vacuum-dried by a vacuum exhaust means. In the second method, the inside of the storage container 12 is vacuum-dried by vacuum evacuation means using a dedicated lid for vacuum drying, and the inside of the moisture removing device 14 is also vacuum-dried by vacuum evacuation means. In the third method, the container 12 is not covered and the inside of the moisture removing device 14 is vacuum-dried by a vacuum exhaust means.

  The moisture separation means 15 is a device that removes moisture from the off-gas 4 generated when moisture is removed from the solidified body by heating and / or reduced pressure, and includes, for example, a cooling tower and a desiccant.

The cooling tower is a device that cools the moisture in the off-gas 4 and collects the moisture in a liquid or solid state. The desiccant is a chemical used to remove moisture in the off-gas 4 and includes, for example, concentrated sulfuric acid. The moisture separation means 15 can prevent a decrease in function due to dew condensation of the off-gas treatment means 16 and can remove moisture containing tritium present as H ₂ O (that is, T ₂ O or HTO).

  The offgas processing means 16 is a device that removes radionuclides present in the offgas 4 by adsorption, combustion, or the like. The off-gas may contain hydrogen, carbon dioxide, volatile organic carbon compounds, chlorine and iodine radionuclides (tritium, C-14, Cl-36, I-129).

  Tritium contained in the hydrogen is removed by the off-gas treatment means 16 equipped with an oxidation catalyst that converts hydrogen into water. The oxidation catalyst for converting hydrogen into water is a catalyst comprising one or more kinds of metals such as Pt, Pd, Ru, Rh, Ir, Os, Ag, Au, Re, Cu, Ni, Co, and Zn. Hydrogen gas is reacted with oxygen under a heating condition using a catalyst such as Pt, and the produced water is recovered.

  C-14 contained in the volatile organic carbon compound is removed by the off-gas treatment means 16 equipped with a device for oxidizing the organic carbon compound gas. The organic carbon compound gas is heated and oxidized to generate carbon dioxide, and then recovered as carbonate ions by a scrubber using an alkaline solution together with carbon dioxide generated from the solidified product.

  Cl-36 and I-129 contained in a halogen gas such as chlorine and iodine are adsorbed and removed by the off-gas treatment means 16 equipped with activated carbon.

  The sealing means (not shown) seals the storage container 12 with a lid.

  The solidified paste containing the radioactive waste 1 and the hydraulic inorganic solidified material 2 is kneaded with the mixer 11 (S1a), and this solidified paste is stored in the storage container 12 (S1b), and this solidified paste is stored. The storage container 12 is transferred into the moisture removing device 14 by the transfer device 13 and cured for a necessary period to form a solidified body. Water is removed from the solidified body in the storage container 12 by heating and / or decompressing (S2). The off-gas 4 generated from the solidified body by this heating and / or decompression is removed by the water separation means 15 (S3), and then the radionuclide in the off-gas 4 is removed by the off-gas treatment means 16 (S4). The container 12 filled with the solidified body from which moisture has been removed in the moisture removing device 14 is covered with a sealing means. The storage container 12 is sealed by welding the outer periphery of the cover or by interposing a sealing material between the cover and the storage container 12 (S5). The sealed storage container 12 is buried in a buried disposal facility (S6).

  The solidified body including the radioactive waste 1 and the hydraulic inorganic solidified material 2 is sufficiently heated to remove moisture, thereby suppressing generation of gas from the solidified body due to radiolysis during the embedding of the solidified body. Can be prevented. Therefore, even if it is a radioactive waste with a high radionuclide concentration, it is possible to suppress or prevent an increase in pressure in the storage container during the long-term burying disposal, and to ensure the soundness of the disposal site for a long period.

  EXAMPLES Next, although an Example demonstrates this invention, this invention is not limited to these Examples.

Example 1
Alumina cement (manufactured by Toshiba Ceramics Co., Ltd.) 625 parts by weight, 375 parts by weight of sand, and 300 parts by weight of tap water are kneaded with a mixer, and the solidified paste is dispensed into a 10 cm high and 5 cm diameter mold for 24 hours. The soil was cured and a solidified body was obtained. This solidified body was heated at 120 ° C. or 200 ° C. to remove moisture.

(Example 2)
Water was removed from the solidified body in the same manner as in Example 1 except that 334 parts by weight of alumina cement (manufactured by Toshiba Ceramics Co., Ltd.), 166 parts by weight of perlite (manufactured by Toshiba Ceramics Co., Ltd.), and 684 parts by weight of tap water were kneaded. .

(Example 3)
Water was removed from the solidified body in the same manner as in Example 1 except that 950 parts by weight of alumina cement (manufactured by Toshiba Ceramics Co., Ltd.), 50 parts by weight of pearlite (manufactured by Toshiba Ceramics Co., Ltd.), and 384 parts by weight of tap water were kneaded. .

Example 4
100 parts by weight of alumina cement (manufactured by Toshiba Ceramics Co., Ltd.), 100 parts by weight of silica fine powder (manufactured by Toshiba Ceramics Co., Ltd.), 100 parts by weight of alumina fine powder (manufactured by Toshiba Ceramics Co., Ltd.), 700 parts by weight of Chamotte (manufactured by Toshiba Ceramics Co., Ltd.) Water was removed from the solidified body in the same manner as in Example 1 except that 250 parts by weight of 0.1% condensed sodium phosphate aqueous solution was kneaded.

(Example 5)
Alumina cement (manufactured by Toshiba Ceramics Co., Ltd.) 100 parts by weight, silica fine powder (manufactured by Toshiba Ceramics Co., Ltd.) 100 parts by weight, alumina fine powder (manufactured by Toshiba Ceramics Co., Ltd.) 100 parts by weight, natural alumina 700 parts by weight, 0.1% condensation Water was removed from the solidified body in the same manner as in Example 1 except that 384 parts by weight of an aqueous sodium phosphate solution was kneaded.

(Comparative example)
Water was removed from the solidified body in the same manner as in Example 1 except that 650 parts by weight of alumina cement (manufactured by Toshiba Ceramics Co., Ltd.) and 350 parts by weight of tap water were kneaded.

  Table 1 shows the raw material composition table of each example and comparative example.

  The results are shown in FIGS. FIG. 3 is a graph showing the change over time in the remaining water amount / initially added water amount (%) when the solidified bodies of Examples 1 to 5 and the comparative example were heated at 120 ° C. to remove moisture. FIG. 4 is a graph showing the change over time in the remaining water amount / initial added water amount (%) when the solidified bodies of Examples 1 to 5 and the comparative example were heated at 200 ° C. to remove moisture.

As is clear from FIGS. 3 and 4, the solidified bodies containing aggregates (Examples 1 to 5) are more easily moisture than the solidified bodies containing no aggregate (comparative examples). It was found that can be removed. In particular, Examples 2, 4, and 5 had a high moisture removal rate, and moisture removal by heating was easy.
3 and 4, the amount of water removed per unit time is large until the heat treatment time is up to about 8 hours, and then the water is removed while the amount of water removed per unit time is reduced. When the time was about 20 hours, the water removal amount tended to be almost saturated.

(Radiation irradiation test)
A radiation irradiation test was performed on the solidified bodies of Examples 2, 4, and 5 that had a high water removal rate in the comparative example and water removal by heating. In the radioactive irradiation test, the solidified body before heat treatment and the solidified body heat-treated at 200 ° C. were partially crushed and sealed in a glass container, and then irradiated with a Co-60 radiation source (9496TBq) to generate hydrogen gas generation amount. Was measured.

  FIG. 5 is a graph showing a hydrogen gas generation rate (hydrogen gas generation amount of solidified body after heating / hydrogen gas generation amount (%) of solidified body before heating) by a radiation irradiation test. For all of Examples 2, 4, 5 and Comparative Examples, the solidified body after the heat treatment has a hydrogen gas generation rate reduced to 20% or less compared to the solidified body before the heat treatment. In the solidified body containing the aggregate No. 5, the hydrogen gas generation rate was reduced to 10% or less by the heat treatment, and the effect of suppressing the hydrogen gas generation by the heat treatment was recognized.

(Uniaxial compressive strength test)
The uniaxial compressive strength of the solidified body after heat treatment at 200 ° C. was measured for Comparative Examples and Examples 2, 4, and 5 that had a high moisture removal rate in removing moisture by heating.
FIG. 6 is a diagram showing the uniaxial compressive strength of the solidified body after the heat treatment at 200 ° C. About Example 4, 5 and the comparative example, it was confirmed that it exceeds 1.5 MPa made into an evaluation reference value.

(Confirmation test of moisture removal method by heating and decompression)
About the comparison example and the solidified body before heat treatment of Examples 2, 4, and 5 whose water removal rate was high in water removal by heating, vacuum heat treatment was performed at 120 ° C., and the change with time of the remaining water amount / initial added water amount (%) Was measured.
In all of Examples 2, 4, 5 and Comparative Examples, it was recognized that when the vacuum heat treatment was performed, the treatment time could be shortened compared to the case of simple heat treatment.

It is a flowchart which shows the procedure of the solidification processing method of the radioactive waste which concerns on one Embodiment of this invention. It is a figure which shows the structure of the solidification processing apparatus of the radioactive waste which concerns on one Embodiment of this invention. It is a figure which shows a time-dependent change of the amount of residual water / initial addition water amount (%) when the solidified body of each Example and a comparative example is heated at 120 degreeC. It is a figure which shows a time-dependent change of the amount of residual water / initial addition water amount (%) when the solidified body of each Example and a comparative example is heated at 200 degreeC. It is a figure which shows the generation rate (hydrogen gas generation amount of the solidified body after a heating / hydrogen gas generation amount (%) of the solidified body before a heating) by a radiation irradiation test. It is a figure which shows the uniaxial compressive strength of the solidified body after a heat processing at 200 degreeC.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Radioactive waste, 2 ... Hydraulic inorganic solidification material, 3 ... Aggregate, 4 ... Off gas, 10 ... Solidification processing apparatus of radioactive waste, 11 ... Mixer, 12 ... Storage container, 13 ... Transfer device, 14 ... Water | moisture content Removal device, 15 ... moisture separation means, 16 ... off-gas treatment means.

Claims (15)

In the radioactive waste solidification method of solidifying radioactive waste that has a high radionuclide concentration to the extent that radiolysis is generated during the disposal of radioactive waste generated from nuclear facilities,
A solidified body forming step of kneading the radioactive waste, a hydraulic inorganic solidified material, and an aggregate, and then supplying the storage container to form a solidified body;
A moisture removing step for removing moisture from the solidified body in the storage container by heating and / or decompression after curing the solidified body in the storage container;
A storage container sealing step for sealing the storage container with a lid after the moisture removal step, and
A solidification method for radioactive waste, comprising: In the radioactive waste solidification method of solidifying radioactive waste that has a high radionuclide concentration to the extent that radiolysis is generated during the disposal of radioactive waste generated from nuclear facilities,
Said radioactive waste, the hydraulic inorganic solidifying material, after supplying the aggregate to the receiving container, the solidified material forming step of forming a solidified body by kneading,
A moisture removing step for removing moisture from the solidified body in the storage container by heating and / or decompression after curing the solidified body in the storage container;
A storage container sealing step for sealing the storage container with a lid after the moisture removal step, and
A solidification method for radioactive waste, comprising: In the radioactive waste solidification method of solidifying radioactive waste that has a high radionuclide concentration to the extent that radiolysis is generated during the disposal of radioactive waste generated from nuclear facilities,
After kneading the radioactive waste, the hydraulic inorganic solidifying material, and the foaming agent, a solidified body forming step of supplying the storage container to form a solidified body,
A moisture removing step for removing moisture from the solidified body in the storage container by heating and / or decompression after curing the solidified body in the storage container;
A storage container sealing step for sealing the storage container with a lid after the moisture removal step, and
A solidification method for radioactive waste, comprising: In the radioactive waste solidification method of solidifying radioactive waste that has a high radionuclide concentration to the extent that radiolysis is generated during the disposal of radioactive waste generated from nuclear facilities,
Said radioactive waste, the hydraulic inorganic solidifying material, after supplying the foaming agents, to container, the solidified material forming step of forming a solidified body by kneading,
A moisture removing step for removing moisture from the solidified body in the storage container by heating and / or decompression after curing the solidified body in the storage container;
A storage container sealing step for sealing the storage container with a lid after the moisture removal step, and
A solidification method for radioactive waste, comprising:   The method for solidifying radioactive waste according to claim 3 or 4, wherein aggregate is supplied together with the radioactive waste, the hydraulic inorganic solidifying material, and the foaming agent to the storage container.   The radioactive waste solidification method according to any one of claims 1 to 5, wherein the heating conditions are a heat treatment temperature of 100 ° C or higher and a heat treatment time of 8 hours or longer.   The radioactive waste solidification method according to any one of claims 1 to 6, wherein the depressurization condition is a processing pressure of 1 kPa or less. The aggregate, sand, gravel, stone, alumina, silica fines, artificial lightweight aggregate, perlite, chamotte, iron powder, claims 1, 2 and 5, characterized in that it consists of at least one selected from concrete waste The solidification processing method of the radioactive waste as described in any one of these. The method for solidifying radioactive waste according to any one of claims 3 to 5 , wherein the foaming agent comprises an amphoteric metal or a surfactant.   The radioactive waste solidification process according to any one of claims 1 to 9, wherein in the storage container sealing step, the lid is fixed to the storage container by welding or a sealing material to form a sealed structure. Method.   The offgas treatment step of removing the radionuclide contained together with moisture in the offgas generated by the heating and / or depressurization by adsorption or combustion is further provided. Solidification method of radioactive waste of description.   The method for solidifying radioactive waste according to claim 11, further comprising a moisture separation step of removing the moisture in the offgas before the offgas treatment step. In the radioactive waste solidification processing equipment that solidifies radioactive waste that has a high radionuclide concentration to the extent that it generates gas by radioactive decomposition during buried disposal among the radioactive waste generated from nuclear facilities,
A moisture removing device that houses a storage container in which a solidified body containing the radioactive waste and the hydraulic inorganic solidified material is stored, and removes moisture of the solidified body in the storage container by heating and / or decompression;
Moisture separation means for removing moisture in the off-gas generated by the heating and / or decompression;
Off-gas treatment means for removing radionuclides from the off-gas from which the moisture has been removed by the moisture separation means;
A solidification processing apparatus for radioactive waste, comprising:   The solidification treatment of radioactive waste according to claim 13, wherein the off-gas treatment means has at least one selected from an oxidation catalyst for converting hydrogen into water, an apparatus for oxidizing an organic carbon compound gas, and activated carbon. apparatus.   The radioactive waste solidification processing apparatus according to claim 13 or 14, wherein the water separation means includes a cooling tower or a desiccant.

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