JP2014228376A - Radioactive material adsorbent, and radioactive material adsorption bag using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radioactive material adsorbent capable of guaranteeing a reaction time between a radioactive material adsorption agent such as zeolite and a radioactive material, and removing the radioactive material efficiently by a simple method, and to provide a radioactive material adsorption bag using the same.SOLUTION: A radioactive material adsorbent 1 comprises a radioactive material adsorption sheet 2 formed by integrating a granular radioactive material adsorption agent 4 and fibers 5 into a sheet shape, and an auxiliary sheet 3 provided on one surface or both surfaces of the radioactive material adsorption sheet 2. A radioactive material adsorption bag 10 formed therefrom in a bag shape is also provided.

Description

  The present invention relates to a radioactive substance adsorbent having a function of adsorbing radioactive substances, and in particular, it is possible to effectively adsorb and remove radioactive substances contained in water-containing radioactive contaminants by a simple usage method, thereby improving the processing performance. The present invention relates to a radioactive substance adsorbent and a radioactive substance adsorbing bag using the same.

  Conventionally, water-containing radioactive contaminants containing radioactive cesium, etc., are treated by separating water and solids, spraying a radioactive material adsorbent such as zeolite, or adsorbing a radioactive material such as zeolite. In general, an adsorbing device or a filter carrying an agent is used.

  Examples of the method for separating water from the solid content include a dehydration method using a sandbag and an aggregation / precipitation treatment of the solid content in a muddy water treatment plant.

  The contaminant separation and removal method described in Patent Document 1 is a contaminant separation and removal method particularly suitable for separating and removing contaminants from topsoil, mud, and the like contaminated with radioactive materials. The method described in Patent Document 1 is a method for separating and removing contaminants from soil contaminated with contaminants at or near the site where the contaminated soil is located. Laying a container for flocculating and flotation, scooping up the soil containing the pollutants at the site and temporarily accumulating it, and excavating the site after the soil has been scooped up or in the vicinity thereof into a predetermined shape , A step of forming an isolating tank by forming a quick-water side wall and a water-impervious bottom wall at the excavated side and bottom, and screening while applying water washing and vibration to the soil containing the temporarily accumulated contaminants The process of sieving into a plurality of sizes by performing the process, the soil components sifted to the minimum size, and the wastewater generated during the washing are put into the isolation tank and agitated. The separation process step for precipitating the sediment component contained in the soil component sifted to the minimum size, and the waste water and floating matter in the isolation tank are extracted and put together with the flocculant into the flocculating and floating separation container. Then, after agitating and mixing, a method of separating and removing pollutants including a process of aeration with microbubbles and introducing a floating substance floating by aeration into a management type container.

  The method described in Patent Document 1 is expensive to install a muddy water treatment plant and is not economically suitable for small-scale treatment. Moreover, it is hard to say that the processing capacity is sufficient. Sedimentation is required after soil classification, and its processing capacity is also reduced to about one-fourth of the radiation dose, and the simplicity and processing capacity of the method are not sufficient.

  Moreover, although processing with a sandbag is suitable for small-scale processing, there is a high possibility that solid contaminants will flow out together with water.

  In addition, the method of spraying radioactive material adsorbents such as zeolite on the soil is certainly effective in preventing the outflow of radioactive materials, but it is difficult not only to spray uniformly, but also to collect the radioactive material adsorbent after adsorption. Is practically difficult.

The radiation substance adsorbing device described in Patent Document 2 is a radiation adsorption that reduces the radiation released to the water by detaching the radiation substance adhering to the object to be cleaned such as food and clothing by water in the water tank. The radiation adsorbing tool comprises a plurality of water-insoluble zeolite particles formed in a granular shape, and a hollow container having a plurality of through-holes having an inner diameter smaller than the zeolite particles. The radiation material adsorbing tool is configured such that the plurality of zeolite particles are movable by the flow of water in the water tank.

  Although the invention described in Patent Document 2 is an adsorbent using zeolite, the particle size of zeolite cannot be made smaller than the plurality of through holes provided in the container, so that the adsorption area cannot be increased. In addition, the time required for the adsorption of the zeolite and the radioactive substance is not taken into consideration, and stable radioactive substance adsorption performance cannot be obtained.

  In addition, using a filter carrying a radioactive material adsorbent such as zeolite is a simple method, but in this case as well, an adsorption time of more than a certain time is required to adsorb the radioactive material to the adsorbent such as zeolite. It is necessary to secure the adsorption time.

Japanese Patent No. 4970627 Utility Model Registration No. 3170857

  The present invention has been made in view of the above circumstances, and guarantees a reaction time between a radioactive substance adsorbent such as zeolite and the radioactive substance, and can efficiently remove the radioactive substance by a simple method and It aims at providing the radioactive substance adsorption bag using this.

As means for solving the above-mentioned problems, the invention according to claim 1 is directed to a radioactive substance adsorbing sheet formed by integrating a granular radioactive substance adsorbent and fibers into a sheet, and the radioactive substance adsorbing sheet. It is a radioactive substance adsorbent characterized by comprising the auxiliary sheet | seat provided in the single side | surface or both surfaces.

  The radioactive substance adsorbent according to the present invention is a combination of a radioactive substance adsorbing sheet formed by integrating a granular radioactive substance adsorbent and fibers into a sheet, and an auxiliary sheet provided on one or both sides of the radioactive substance adsorbing sheet. As a result, the particle size and loading amount of the adsorbent, the thickness and water permeability of the sheet, the overall rigidity, etc. can be optimally designed according to the purpose.

The invention according to claim 2 is the radioactive material adsorbent according to claim 1, wherein the radioactive material adsorbent is zeolite and the amount of zeolite supported is 100 g / m ² or more. .

  The invention according to claim 3 is the radioactive substance adsorbent according to claim 1 or 2, wherein the radioactive substance adsorbent contains mordenite-type zeolite in a weight ratio of 50% or more.

  The radioactive substance adsorbent according to any one of claims 1 to 3, wherein the radioactive substance adsorbent has an average particle diameter of 1 μm or more and 1000 μm or less. It is.

  In the invention described in claim 5, the air permeability of the radioactive substance adsorbent is 25 μm / (Pa · s) or more and 600 μm / (Pa · s) or less. It is a radioactive substance adsorption body of any one of -4.

  The invention according to claim 6 is a radioactive substance characterized in that the radioactive substance adsorbent according to any one of claims 1 to 5 is formed into a bag shape so that the auxiliary sheet is an outer surface. Adsorption bag.

  The invention according to claim 7 is characterized in that the auxiliary sheet on the outer surface forms a mesh-shaped outer bag having an opening ratio of 0.5% to 50%. It is a radioactive material absorption bag.

  The invention according to claim 8 is the radioactive substance absorption bag according to claim 6, comprising a mesh-shaped outer bag having an opening ratio of 0.5% to 50%.

  Since the radioactive substance adsorbent according to the present invention uses a radioactive substance adsorbing sheet in which granular radioactive substance adsorbents and fibers are integrated into a sheet, a wide range of combinations can be obtained depending on the combination of the radioactive substance adsorbent and fibers. It is possible to realize a radioactive material adsorbing sheet having optimum characteristics according to the purpose among various characteristics.

  In addition, since the auxiliary sheet is provided on one or both sides of the radioactive substance adsorbing sheet, the strength of the radioactive substance adsorbing sheet decreases, for example, when the carrying amount of the radioactive substance adsorbent in the radioactive substance adsorbing sheet is very large. Even in such a case, by appropriately selecting the auxiliary sheet, the overall strength can be ensured, for example, the degree of freedom of design is increased, and the optimum design according to the application becomes possible.

When the radioactive material adsorbent is zeolite and the amount of zeolite supported is 100 g / m ² or more as in the invention described in claim 2, a sufficient adsorption amount for radioactive cesium and radioactive strontium is obtained. Can be secured.

  In addition, when the radioactive material adsorbent contains 50% or more of mordenite zeolite by weight as in the invention described in claim 3, a high CEC (cation exchange capacity) as high as 140 meq / 100 g can be obtained. . Further, with respect to cesium ions having a diameter of 0.338 nm, the mordenite-type zeolite has a pore size approximating 0.4 to 0.8 nm, and thus has high adsorptivity and hardly desorbs.

  When the average particle size of the radioactive material adsorbent is 1 μm or more and 1000 μm or less as in the invention described in claim 4, it is stable to mix with fibers to form a slurry and to form a sheet by a papermaking method. It becomes possible.

  Further, when the air permeability of the auxiliary sheet is 25 μm / (Pa · s) or more and 600 μm / (Pa · s) or less as in the invention described in claim 5, the radioactive sheet is adsorbed by the auxiliary sheet. Is not inhibited, and the performance of the radioactive substance adsorbing sheet is sufficiently exhibited.

  According to the radioactive substance adsorbing bag according to claim 6, it is possible to treat the object to be processed by a simple operation of simply putting the water-containing radioactive substance contaminant into the bag, and easily prevent the diffusion of the radioactive contaminant. Can do.

  According to invention of Claim 7 or 8, since the mesh-shaped outer bag whose opening rate is 0.5% or more and 50% or less exists as an outermost layer, inhibiting dehydration of a water-containing radioactive substance contaminant. In addition, the handleability of the bag can be improved.

FIG. 1 is a schematic cross-sectional view showing one embodiment of a radioactive substance adsorbent according to the present invention, which is an example in which an auxiliary sheet is provided on one side of a radioactive substance absorbent sheet. FIG. 2 is a schematic cross-sectional view showing another embodiment of the radioactive substance adsorbent according to the present invention, which is an example in which auxiliary sheets are provided on both sides of the radioactive substance absorbent sheet. FIG. 3 is a schematic view showing an embodiment of a radioactive substance adsorbing bag using the radioactive substance adsorbent according to the present invention. FIG. 4 is a schematic view showing another embodiment of a radioactive substance adsorbing bag using the radioactive substance adsorbent according to the present invention. FIG. 5 is a schematic view showing another embodiment of the radioactive substance adsorbing bag using the radioactive substance adsorbent according to the present invention.

Hereinafter, a radioactive substance adsorbent according to the present invention and a radioactive substance adsorbing bag using the same will be described in detail with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing an embodiment of the radioactive substance adsorbent (1) according to the present invention, and is an example in which an auxiliary sheet (3) is provided on one side of the radioactive substance absorbent sheet (2). .
FIG. 2 is a schematic cross-sectional view showing another embodiment of the radioactive substance adsorbent (1) according to the present invention, in which auxiliary sheets (3) are provided on both sides of the radioactive substance absorbent sheet (2). It is an example.

  The radioactive substance adsorbent (1) according to the present invention includes a radioactive substance adsorbing sheet (2) formed by integrating a granular radioactive substance adsorbent (4) and fibers (5) into a sheet, and a radioactive substance adsorbing material. And an auxiliary sheet (3) provided on one or both sides of the sheet.

  The radioactive material absorbent (4) includes activated carbon, silica gel, kaolin, montmorillonite (acid clay), clay, bentonite, diatomaceous earth, zeolite, chitin, chitosan, etc. Substances having the property of adsorbing can be used, and among these, when attention is paid to the adsorptivity to radioactive cesium and radioactive strontium, zeolite having an ion exchange action on these is most preferable.

When zeolite is used as the radioactive material adsorbent (4), the supported amount of zeolite in the radioactive material adsorbing sheet (2) is preferably 100 g / m ² or more. If the supported amount of zeolite is 100 g / m ² or more, a practically sufficient adsorption ability can be exhibited for radioactive substances such as radioactive cesium and radioactive strontium.

  As zeolites, natural zeolites such as mordenite, clinoptilolite, anarchin, chabasite, erionite, faujasite and artificial zeolites such as A-type zeolite, X-type zeolite, and Y-type zeolite can be used. One or two or more kinds of zeolites can be appropriately selected and used.

  As the radioactive substance adsorbent (4), mordenite-type zeolite is most suitable, and the mordenite-type zeolite is preferably 50% or more by weight in the total weight of the radioactive substance adsorbent. When the mordenite-type zeolite is 50% or more by weight in the total weight of the active substance adsorbent, particularly high adsorptivity to cesium ions is exhibited.

Moreover, as a particle size of granular radioactive substance adsorbent (4), an average particle diameter is 1 micrometer or more and 100.
It is desirable that it is 0 μm or less. When the radioactive substance adsorbing sheet (2) used for the radioactive substance adsorbent of the present invention is produced by a wet papermaking method or a dry papermaking method, the average particle diameter of the granular radioactive substance adsorbent (4) is 1 μm or more and 1000 μm. The thickness is preferably 1 μm or more and 500 μm or less. If the diameter of the radioactive material adsorbent (4) is less than 1μm, the paper making wire will fall out during paper making and the yield will be greatly reduced. Therefore, the radioactive material adsorbent (4) is contained in the set amount of the radioactive material adsorbent (2). It becomes difficult to make it. On the other hand, when the diameter exceeds 1000 μm, the cohesiveness decreases, and the fiber (5) cannot hold the radioactive substance adsorbent (4) with sufficient strength. Therefore, after drying, the radioactive substance adsorbed from the radioactive substance adsorbing sheet (2). The agent (4) may fall off.

  In the present invention, the average particle size is a value calculated by a laser diffraction / scattering method using a laser diffraction / scattering particle size distribution measuring apparatus.

  The fiber (5) supports the granular radioactive substance adsorbent (4) and plays a role of forming the radioactive substance adsorbing sheet (2) into a sheet shape. Examples of the fibers (5) include mechanical pulp such as ground wood pulp (GP), pressure-rise ground wood pulp (PGW), and thermomechanical pulp (TMP), and high yield unbleached kraft pulp (HNKP; N material). , Soft pulp bleached kraft pulp (NBKP; N material, NB material), hardwood end bleached kraft pulp (LUKP; L material), hardwood bleached kraft pulp (LBKP; L material), etc., chemical pulp, deinking pulp (DIP), waste Waste paper pulp such as pulp (WP) and wood pulp such as semi-chemical pulp (CP) can be used.

  In addition, as natural fibers other than wood, pulp-like fibers such as cotton, straw, bamboo, esparto, bagasse, linter, manila hemp, flax, hemp, jute, and husk can be used, and one or more of these fibers can be used. Can be appropriately selected and used. In particular, softwood bleached kraft pulp (NBKP; N material, NB material) is preferable because of its long fiber length and strong sheet strength.

  The above-mentioned various fibers are the main fibers, and auxiliary fibers include rayon, acetate, triacetate, nylon 6, nylon 66, vinylon, vinylidene, polyvinyl chloride, polyester, acrylic, polyethylene, polypropylene, polyurethane, aramid, polyvinyl alcohol, and the like. These organic polymer fibers, glass fibers, carbon fibers, activated carbon fibers, alumina fibers, rock wool fibers, and other inorganic fibers, stainless steel, and other metal fibers can be appropriately selected and used alone or in combination.

  For example, when it is desired to improve the strength and water resistance of the radioactive substance adsorbing sheet (2), it is preferable to use organic polymer fibers that exhibit a heat-sealing function at 90 to 250 ° C. Here, the heat fusion means an adhesion function by melting or softening.

  As the organic polymer fiber used in this case, for example, a bilayer structure of a core / sheath, a composite fiber such as PP (polypropylene) / PP, PP / PE (polyethylene), PET (polyethylene terephthalate) / low melting point PET, Examples thereof include a core-sheath structure such as a low-melting-point PET fiber or a PP fiber, and a heat-sealing fiber having a single component structure.

The fineness of the auxiliary fiber used by mixing with the main fiber is preferably 0.5 to 20 dtex, and more preferably 1 to 5 dtex. If the fiber is too thin, the strength is insufficient. If the fiber is too thick, the number of fibers per unit weight is reduced although the fiber strength is strong. As a result, the heat-sealed portion is reduced and the strength is insufficient. Further, the fiber length of the auxiliary fiber is preferably about 1 to 15 mm, and more preferably about 3 to 7 mm. If the fiber is too short, the strength will be insufficient, and if it is too long, it will be difficult to make paper. The mixing amount of the auxiliary fiber is preferably 1 to 50 percent by weight (wt%), more preferably about 3 to 30 wt% with respect to the main fiber. If the amount of the auxiliary fiber is too small, the strength is insufficient. If the amount is too large, the sheet becomes stiff and hard, and the bendability and workability are impaired.

  Furthermore, when it is desired to improve the strength and water resistance of the radioactive substance adsorbing sheet (2), a plurality of the fibers (5) may be bonded together.

  The auxiliary sheet (3) has a function of improving the shape retention, strength, rigidity, etc. of the radioactive substance adsorbing sheet (2) as a backing material or reinforcing material of the radioactive substance adsorbing sheet (2). It can be provided on one side or both sides of the substance adsorbing sheet (2). When provided on both surfaces, the auxiliary sheets (3) on the front and back surfaces may be made of different materials and specifications.

  As the auxiliary sheet (3), a sheet-like material obtained by processing various fibers into a sheet shape or a plate shape can be used. As the sheet material, paper, non-woven fabric, woven fabric, knitted fabric, felt or the like is used.

  The fibers used in the auxiliary sheet (3) include organic polymers such as rayon, acetate, triacetate, nylon 6, nylon 66, vinylon, vinylidene, polyvinyl chloride, polyester, acrylic, polyethylene, polypropylene, polyurethane, aramid, and polyvinyl alcohol. Fiber, glass fiber, carbon fiber, activated carbon fiber, inorganic fiber such as alumina fiber and rock wool fiber, metal fiber such as stainless steel, etc., and grandwood pulp (GP), pressure-rise grandwood pulp (PGW), thermomechanical pulp Mechanical pulp such as (TMP), softwood high yield unbleached kraft pulp (HNKP; N material), softwood bleached kraft pulp (NBKP; N material, NB material), hardwood unbleached kraft pulp (LUKP; L material), hardwood bleach Kraft pulp LBKP, L material) and other chemical pulp, deinking pulp (DIP), waste pulp such as waste pulp (WP) and wood pulp such as semi-chemical pulp (CP), and natural fibers other than wood include cotton, Pulp-like fibers such as straw, bamboo, esparto, bagasse, linter, manila hemp, flax, hemp, jute, and husk can be selected as appropriate and used alone or in combination. In particular, from the viewpoint of air permeability, organic polymer fibers such as rayon, acetate, triacetate, nylon 6, nylon 66, vinylon, vinylidene, polyvinyl chloride, polyester, acrylic, polyethylene, polypropylene, polyurethane, aramid, and polyvinyl alcohol are preferable.

  The method for producing the radioactive substance adsorbent (1) used in the present invention is not particularly limited. For example, the fiber (5) and the radioactive substance adsorbent described above using a wet papermaking method or a dry papermaking method are used. (4) is blended at a predetermined ratio to form an integral sheet to obtain a radioactive substance adsorbing sheet (2). For example, the auxiliary sheet (3) is sewn or bonded to the radioactive substance adsorbing sheet ( The radioactive substance adsorbent (1) can be manufactured by installing on at least one side of 2).

  In addition, in the radioactive substance adsorbing bag (10) described later, when the auxiliary sheet (3) is used as the outer bag (11), the radioactive substance adsorbing sheet (2) and the auxiliary sheet (3) are stitched together. There is a case where it is only necessary to sew it into a bag shape in a state of being overlapped without the need for pasting.

  When the radioactive substance adsorbing sheet (2) is produced by a wet papermaking method, a slurry is prepared by dispersing the blended material in water, and the resulting slurry is made with a wet papermaking machine (papermaking process). The fiber (5) as the main fiber is preferably beaten in advance. The beating can be appropriately performed by a beating machine such as a single disc reiner (SDR), a double disc reiner (DDR), or a beater. As the beating degree, Canadian standard freeness (CSF: JIS P8121) is preferably about 750 CSF to 100 CSF, more preferably about 500 CSF to 150 CSF.

  In the paper making process, a flocculant can be appropriately used. The flocculant is not particularly limited, but various anionic, nonionic, cationic or amphoteric flocculants can be used. For example, polyacrylamide-based cationic, nonionic, anionic and amphoteric resins, polyethyleneimine and its derivatives, polyethylene oxide, polyamine, polyamide, polyamide polyamine and its derivatives, cationic and amphoteric starch, oxidized starch, carboxymethyl Organic compounds such as modified starch, plant gum, polyvinyl alcohol, urea formalin resin, melamine formalin resin, hydrophilic polymer particles, and sulfuric acid band, alumina sol, basic aluminum sulfate, basic aluminum chloride, basic polyaluminum hydroxide In addition, aluminum compounds such as ferrous sulfate, ferrous chloride, colloidal silica, bentonite, and other inorganic compounds can be used in combination.

  In the papermaking process, the addition of the flocculant and the addition amount thereof are arbitrary, but when the flocculant is added, 0.001 wt% or more is preferable with respect to the solid content in the aqueous dispersion, and 0.005 wt% or more is preferable. More preferred. If the amount added is less than 0.001 wt%, the aggregation effect may not be obtained.

  In the paper making process, paper making chemicals such as a sizing agent, a wet paper strength agent, and a filler can be used as needed. The sizing agent is not particularly limited. For example, rosin sizing agent for acidic paper making, petroleum resin sizing agent, alkyl ketene dimer sizing agent for neutral paper making, alkenyl succinic anhydride size Various sizing agents such as agents are included.

  Examples of the wet paper strength enhancer include melamine resin, urea resin, polyamide epichlorohydrin resin, epoxy resin, dialdehyde starch, polyacrylamide, and polyethyleneimine.

  Examples of fillers include mineral fillers such as talc, kaolin, calcined kaolin, clay, diatomaceous earth, heavy calcium carbonate, magnesium carbonate, aluminum hydroxide, titanium dioxide, magnesium sulfate, silica, aluminosilicate, bentonite, and polystyrene. Examples thereof include organic synthetic fillers such as particles and urea formalin resin particles.

  Furthermore, various additive aids for papermaking such as dyes, pH adjusters, slime control agents, antifoaming agents, and stickers can be used depending on the application.

  The wet paper machine used in the paper making process is not particularly limited, such as a long paper machine, a circular paper machine, an inclined paper machine, and a twin wire paper machine, which are applied to general paper making technology. Further, the radioactive substance adsorbing sheet (2) of the present invention may be configured as a single layer sheet obtained as described above, or as a multi-layered laminated sheet in which single layer sheets are stacked.

The thickness, basis weight, strength, and the like of the radioactive substance adsorbing sheet (2) may be appropriately adjusted according to the application. From the viewpoint of the radioactive substance adsorption performance, suitable performance can be exhibited at a basis weight of about 100 to 2000 g / m ² .

  The content of the radioactive substance adsorbent (4) necessary for the radioactive substance adsorbing sheet (2) to achieve the above-mentioned basis weight range varies somewhat depending on the material. For example, in the case of zeolite, the fiber (5) (The total of the main fibers and auxiliary fibers when auxiliary fibers are mixed) 1, the zeolite is at least 0.25 or more by weight, more preferably 0.5 or more.

When laminating the radioactive substance adsorbing sheet (2) and the auxiliary sheet (3) by sewing, it is preferable to sew them together with a sewing machine or the like. Also, from the viewpoint of outflow of radioactive material, a bonding method is desirable when sewing holes become a problem. For the bonding, for example, an adhesive, an adhesive, a hot melt agent, a thermoplastic resin, a thermosetting resin, or the like can be used as appropriate.

  The air permeability of the radioactive substance adsorbent (1) is preferably 25 μm / (Pa · s) or more and 600 μm / (Pa · s) or less. When the air permeability is less than 25 μm / (Pa · s), the permeability of the liquid to be treated is deteriorated, and the processing ability as the radioactive substance adsorbent (1) may be lowered. Further, when the air permeability exceeds 600 μm / (Pa · s), the permeability is too good and the processing capability may be reduced.

  Here, the air permeability is a numerical value defined in JIS P8117 “Paper and paperboard—Air permeability and air resistance test method—Gurley method”.

  3-5 is the schematic diagram which showed the embodiment of the radioactive substance adsorption | suction bag (10) using the radioactive substance adsorbent (1) based on this invention. The radioactive substance adsorbing bag (10) shown in FIG. 3 includes a radioactive substance adsorbing body (1) comprising one radioactive substance adsorbing sheet (2) and an auxiliary sheet (3) provided on one side thereof. 3) is formed so as to be on the outside and formed into a bag shape. Moreover, the radioactive substance adsorption bag (10) shown in FIG. 4 is provided with a mesh-shaped outer bag (11) outside the radioactive substance adsorption bag (10) of FIG. The radioactive substance adsorption bag (10) shown in FIG. 5 is an example in which the auxiliary sheet (3) functions as an outer bag (11).

  The radioactive substance adsorbing bag (10) can separate only clean water by a simple operation of putting in water-containing radioactive substance contaminants so as to put earth and sand into the sandbag. As a result, it is possible to easily reduce the volume of water-containing radioactive material contaminants and to make it easy to handle.

  The outer bag (11) of the radioactive substance adsorbing bag (10) is preferably mesh-shaped and has an opening ratio of 0.5% or more and 50% or less. The outer bag (11) complements the auxiliary sheet (3) of the radioactive substance adsorbent (1), and the handleability of the radioactive substance adsorption bag (10) can be improved by the presence of the outer bag. .

  The outer bag (11) has a mesh opening ratio of 0.5% or more in order to exhibit the ability to hold the radioactive substance adsorbing bag (10) without impairing the drainage of the radioactive substance adsorbent (1). It is preferable that it is 50% or less.

  Further, as in the embodiment shown in FIG. 5, the auxiliary sheet (3) of the radioactive substance adsorbent (1) is assumed to be mesh-shaped and the aperture ratio is 0.5% or more and 50% or less. It is good also as an outer bag (11). In this case, the radioactive substance adsorbing sheet (2) and the auxiliary sheet (3) are not sewed or bonded in advance, but are simply overlapped and sewed into a bag shape to obtain the radioactive substance adsorbing bag (10). It can also be.

As a usage method of the radioactive substance adsorbent (1) according to the present invention, various usage methods can be used in addition to the use as the radioactive substance adsorption bag (10). For example, various applications such as a method of attaching to a frame and using it as a filter, a method of stacking in layers at intervals and flowing water between layers to perform adsorption treatment are possible.
Hereinafter, based on an Example, it demonstrates further more concretely about the radioactive substance adsorbent (1) based on this invention.

As fiber (5), NBKP adjusted to 450 CSF using a beating machine (DDR) is used as a radioactive material adsorbent (4). And an average particle size of 131 μm). After blending the fiber (5) at a ratio of 70 g / m ² and the radioactive material adsorbent (4) at a ratio of 280 g / m ² , the wet paper strength agent (trade name WS4024, manufactured by Seiko PMC Co., Ltd.) with respect to the total amount of raw material pulp. And 0.5 wt% of dry paper strength agent (trade name DS4356, manufactured by Seiko PMC Co., Ltd.) was blended to obtain a raw material slurry.

An agglomerate dispersion was prepared by adding 0.005 wt% of a flocculant (trade name polytension manufactured by Arakawa Chemical Co., Ltd.) to 100 parts by weight of the solid content of the raw slurry. This aggregate dispersion was made with an inclined paper machine to obtain a radioactive substance adsorbing sheet (2) having a basis weight of 350 g / m ² .
As the auxiliary sheet (3), a non-woven fabric (trade name B7202W manufactured by Unicel Corporation) is used, and the radioactive substance adsorbing sheet (2) and the auxiliary sheet (3) are laminated by sewing, and the radioactive substance adsorbing body (1) is obtained. Obtained.

<Comparative Example 1>
As fiber (5), NBKP adjusted to 450 CSF using a beating machine (DDR) is used as a radioactive material adsorbent (4). ) Was prepared. After blending the fiber (5) at a ratio of 60 g / m ² and the radioactive material adsorbent (4) at a ratio of 70 g / m ² , the wet paper strength agent (trade name WS4024, manufactured by Seiko PMC Co., Ltd.) with respect to the total amount of raw material pulp. And 0.5 wt% of dry paper strength agent (trade name DS4356, manufactured by Seiko PMC Co., Ltd.) was blended to obtain a raw material slurry.

An agglomerate dispersion was prepared by adding 0.005 wt% of a flocculant (trade name polytension manufactured by Arakawa Chemical Co., Ltd.) to 100 parts by weight of the solid content of the raw slurry. This aggregate dispersion was made with an inclined paper machine to obtain a radioactive substance adsorbing sheet (2) having a basis weight of 350 g / m ² .
As the auxiliary sheet (3), a non-woven fabric (trade name B7202W manufactured by Unicel Corporation) is used, and the radioactive substance adsorbing sheet (2) and the auxiliary sheet (3) are laminated by sewing, and the radioactive substance adsorbing body (1) is obtained. Obtained.

<Comparative example 2>
As fiber (5), NBKP adjusted to 450 CSF using a beating machine (DDR) is used as a radioactive material adsorbent (4). ) Was prepared. After blending fiber (5) at a ratio of 280 g / m ² and radioactive material adsorbent (4) at a ratio of 70 g / m ² , the wet paper strength agent (trade name WS4024 manufactured by Seiko PMC Co., Ltd.) with respect to the total amount of raw material pulp. And 0.5 wt% of dry paper strength agent (trade name DS4356, manufactured by Seiko PMC Co., Ltd.) was blended to obtain a raw material slurry.

An agglomerate dispersion was prepared by adding 0.005 wt% of a flocculant (trade name polytension manufactured by Arakawa Chemical Co., Ltd.) to 100 parts by weight of the solid content of the raw slurry. This aggregate dispersion was made with an inclined paper machine to obtain a radioactive substance adsorbing sheet (2) having a basis weight of 350 g / m ² .
As the auxiliary sheet (3), a non-woven fabric (trade name B7202W manufactured by Unicel Corporation) is used, and the radioactive substance adsorbing sheet (2) and the auxiliary sheet (3) are laminated by sewing, and the radioactive substance adsorbing body (1) is obtained. Obtained.

<Comparative Example 3>
A sandbag (UV Black Dochu, manufactured by Ebara Industries Co., Ltd.) was used as Comparative Example 3.

The radioactive contaminant removal performance of the radioactive substance adsorbers of Example 1 and Comparative Examples 1 to 3 will be described.
<Experiment 1 Filtration Test of High Moisture Sludge>
In the filtration test of high water content sludge, the radioactive material absorbers of Example 1 and Comparative Examples 1 and 2 and the sandbag of Comparative Example 3 were formed into a bag shape so that the filtration area would be 10 cm square. Processed and tested.
In the test, high water content sludge (water content ratio: 95.1%) was put in each sample, each was hung, and filtered water was received in a container received underneath. The test was conducted using 1 kg of high water content sludge and a filtration area of 10 cm square. After completion of filtration, water was collected and the respective radioactivity concentrations were measured. The radioactivity concentration was measured with a NaI (TI) scintillation spectrometer.

<Experiment 2 air permeability measurement>
In the air permeability measurement, the measurement was performed using the radioactive substance absorbers of Example 1 and Comparative Examples 1 and 2 and the sandbag of Comparative Example 3.
The measurement was performed according to JIS P8117 using a Gurley type densometer. The time t through which 100 ml of air permeated was measured with a Gurley type densometer, and the air permeability P was calculated by the following equation.
P = 135.3 / t
The results are shown in Table 1. When Example 1 is used, the radioactive concentration of water after filtration is 100 Bq / kg or less, the filtration time is 10 minutes or less, and it is possible to remove and collect radioactive contaminants by a simple method. I understood.

  Next, the radioactive substance adsorption bag (10) according to the present invention will be specifically described based on examples.

  As the outer bag (11), a flexible container (1200KS / BWB manufactured by Fukunaga Engineering) was used. As fiber (5), NBKP adjusted to 450 CSF using a beating machine (DDR) was used. As a radioactive material adsorbent (4), zeolite (trade name: MG Iwamilite-0.5 mm, manufactured by Mitsui Kinzoku Resources Development Co., Ltd.) was prepared.

After blending fiber (5) at a ratio of 70 g / m ² and zeolite at a ratio of 280 g / m ² , 0.5 wt% of wet paper strength agent (trade name WS4024 manufactured by Seiko PMC Co., Ltd.) is added to the total amount of raw material pulp. 0.5 wt% of a dry paper strength agent (trade name DS4356, manufactured by Seiko PMC Co., Ltd.) was blended to obtain a raw material slurry.

An agglomerate dispersion was prepared by adding 0.005 wt% of a flocculant (trade name polytension manufactured by Arakawa Chemical Co., Ltd.) to 100 parts by weight of the solid content of the raw slurry. This aggregate dispersion was made with an inclined paper machine to obtain a radioactive substance adsorbing sheet (2) having a basis weight of 350 g / m ² .
The radioactive material adsorbing sheet (2) is subjected to a sewing process, processed into the same form as the outer bag (11), and placed inside the outer bag (11) to obtain the radioactive material adsorbing bag (10) of Example 2. It was.

<Comparative example 4>
As an outer bag (11), a flexible container (1200KS / BWB manufactured by Fukunaga Engineering), a fiber (5), NBKP adjusted to 450 CSF using a beating machine (DDR), a radioactive substance adsorbent (4), zeolite (Trade name: MG Iwamilite-0.5 mm, manufactured by Mitsui Kinzoku Resources Development Co., Ltd.) was prepared. After blending fiber (5) at a ratio of 270 g / m ² and zeolite at a rate of 80 g / m ² , 0.5 wt% of wet paper strength agent (trade name WS4024 manufactured by Seiko PMC Co., Ltd.) is added to the total amount of raw material pulp. A dry paper strength agent (trade name DS4356, manufactured by Seiko PMC Co., Ltd.) was blended in an amount of 0.5 wt% to obtain a raw material slurry.

An agglomerate dispersion was prepared by adding 0.005 wt% of a flocculant (trade name polytension manufactured by Arakawa Chemical Co., Ltd.) to 100 parts by weight of the solid content of the raw slurry. This aggregate dispersion was made with an inclined paper machine to obtain a radioactive substance adsorbing sheet (2) having a basis weight of 350 g / m ² .
The radioactive substance adsorbing sheet (2) was subjected to a sewing process, processed into the same form as the outer bag (11), and placed inside the outer bag (11) to obtain the radioactive substance adsorbing bag of Comparative Example 4.

<Comparative Example 5>
As an outer bag (11), a flexible container (1200KS / BWB manufactured by Fukunaga Engineering), a fiber (5), NBKP adjusted to 450 CSF using a beating machine (DDR), a radioactive substance adsorbent (4), zeolite (Trade name: MG Iwamilite-0.5 mm, manufactured by Mitsui Kinzoku Resources Development Co., Ltd.) was prepared. After blending the fiber (5) at a ratio of 60 g / m ² and zeolite at a ratio of 70 g / m ² , the wet paper strength agent (trade name WS4024 manufactured by Seiko PMC Co., Ltd.) is 0.5 wt% with respect to the total amount of raw material pulp. 0.5 wt% of a dry paper strength agent (trade name DS4356, manufactured by Seiko PMC Co., Ltd.) was blended to obtain a raw material slurry.

An agglomerate dispersion was prepared by adding 0.005 wt% of a flocculant (trade name polytension manufactured by Arakawa Chemical Co., Ltd.) to 100 parts by weight of the solid content of the raw slurry. This aggregate dispersion was made with an inclined paper machine to obtain a radioactive substance adsorbing sheet (2) having a basis weight of 350 g / m ² .

  The radioactive substance adsorbing sheet (2) was subjected to a sewing process, processed into the same form as the outer bag (11), and placed inside the outer bag (11) to obtain the radioactive substance adsorbing bag of Comparative Example 5.

<Comparative Example 6>
A sandbag (UV Black Dochu, manufactured by Ebara Industries Co., Ltd.) was used as Comparative Example 6.

The radioactive contaminant storage performance of the radioactive substance adsorbing bags of the examples and comparative examples described above will be described.
<Experiment 1 Storage Test for High Moisture Sludge>
In the storage test of the high water content sludge, the case of the radioactive material adsorption bag (10) of Example 2 and Comparative Examples 4 and 5 and the case of using the sandbag of Comparative Example 6 were performed for the high water content sludge.
In the test, a high water content sludge (water content ratio: 95.1%) was put into the radioactive material adsorption bag (10) of Example 2 and the sandbag of Comparative Example 6, and each was suspended and dehydrated in a container received underneath. Received the water. After the dehydration, water was collected and the radioactivity concentration of each was measured. The radioactivity concentration was measured with a NaI (TI) scintillation spectrometer.

  In addition, the water content ratio of the high water content sludge and the sludge dehydrated with the radioactive material adsorption bags (10) of Example 2, Comparative Examples 4 and 5 and the sandbags of Comparative Example 6 were measured in accordance with JIS A1203. It was measured.

Moreover, the air permeability measurement of the radioactive substance adsorption bag (10) of Example 2 and Comparative Examples 4 and 5 and the sandbag of Comparative Example 6 was performed according to JIS P8117 using a Gurley type densometer. The time t through which 100 ml of air permeated was measured with a Gurley type densometer, and the air permeability P was calculated by the following equation.
P = 135.3 / t

The results are shown in Table 2.

  As a result of performing dehydration treatment using the radioactive substance adsorption bag of Example 2, the concentration of radioactive contaminants flowing out to the outside became 0.1% or less, which satisfied the drainage standard of the specified general waste treatment facility maintenance management standard. . In addition, the moisture content of the contaminants was 50% or less, and the volume reduction performance was also demonstrated.

  On the other hand, in the radioactive material adsorption bag and sandbag used as a comparative example, the moisture content of the contaminants was 50% or less and the volume was reduced, but the concentration of radioactive contaminants flowing out was 5% or more. As a result, the wastewater standards of the specified municipal solid waste treatment facility maintenance management standards could not be satisfied, and post-treatment was required.

  As described above, according to the radioactive substance adsorption bag (10) of the present embodiment, since it is excellent in handleability, the contaminants are not allowed to flow out by a simple method, and the contaminants are naturally dehydrated. The volume can be reduced and stored.

  As explained above, according to the radioactive substance absorber (1) and the radioactive substance adsorbing bag (10) of the present embodiment, the radioactive substance is removed by a simple method in consideration of the reaction time between the zeolite and the radioactive substance. It is possible to provide a radioactive substance adsorbent or a radioactive substance adsorption bag that can be removed.

  The embodiments of the present invention have been described above. However, the technical scope of the present invention is not limited to the above-described embodiments, and various modifications may be made to each component without departing from the spirit of the present invention. , Can be deleted.

DESCRIPTION OF SYMBOLS 1 ... Radioactive material adsorption body 2 ... Radioactive material adsorption sheet 3 ... Auxiliary sheet 4 ... Radioactive material adsorption agent 5 ... Fiber 10 ... Radioactive material adsorption bag 11 ... Outer bag

Claims (8)

  A radioactive substance comprising a radioactive substance adsorbing sheet formed by integrating a granular radioactive substance adsorbent and fibers into a sheet, and an auxiliary sheet provided on one or both sides of the radioactive substance adsorbing sheet Adsorbent. The radioactive substance adsorbent according to claim 1, wherein the radioactive substance adsorbent is zeolite and the amount of zeolite supported is 100 g / m ² or more.   The radioactive substance adsorbent according to claim 1 or 2, wherein the radioactive substance adsorbent contains mordenite-type zeolite in a weight ratio of 50% or more.   The radioactive substance adsorbent according to any one of claims 1 to 3, wherein the radioactive substance adsorbent has an average particle diameter of 1 µm or more and 1000 µm or less.   5. The radioactive substance according to claim 1, wherein an air permeability of the radioactive substance adsorbent is 25 μm / (Pa · s) or more and 600 μm / (Pa · s) or less. Adsorbent.   A radioactive substance adsorbing bag, wherein the radioactive substance adsorbing body according to any one of claims 1 to 5 is formed into a bag shape so that an auxiliary sheet becomes an outer surface.   The radioactive material absorption bag according to claim 6, wherein the auxiliary sheet on the outer surface forms a mesh-shaped outer bag having an opening ratio of 0.5% or more and 50% or less.   The radioactive substance absorption bag according to claim 6, further comprising a mesh-shaped outer bag having an opening ratio of 0.5% to 50%.

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