Patent Application
20190074097
The present disclosure relates to a method for accommodating waste pieces obtained by cutting radioactive waste efficiently into a storage container, and a waste body produced by the method.
Radioactive waste discharged from a nuclear facility, for instance, is stored permanently in a completely sealed state. Thus, the amount of stored radioactive waste keeps increasing year by year, and the storage cost is also rising. Under such a situation, it is desirable to reduce the volume of radioactive waste as much as possible.
Patent Document 1 discloses a cutting volume reduction device for cutting a control-rod cluster guide tube into segments and accommodating the segments into individual storage containers, to enable safe recovery of control-rod cluster guide tubes disposed inside a reactor vessel. Furthermore, Patent Document 2 discloses a volume reduction process of placing a thin board on a cartridge accommodating radioactive waste, pressing the board from above with a compressing device, accommodating another radioactive waste while maintaining the compressed state, and repeating the process of pressurizing from above in turn, before fixing the top part with a lid. Moreover, Patent Document 2 discloses a volume reduction processing device for pulverizing radioactive waste, and compressing an accommodation bag filled with the pulverized matters by evacuation.
Patent Document 1: JP2014-098596A
Patent Document 2: JP2000-065990A
Patent Document 3: JP2011-080873A
However, in the accommodation method described in Patent Document 1, there is no measure for improving the efficiency of filling a storage container with the plurality of segments obtained by dividing a control-rod cluster guide tube, and thus the accommodation space inside the storage container is not fully utilized. Thus, the accommodation method described in Patent Document 1 has a problem that an unnecessarily large number of storage containers are required. In other words, in the invention of Patent Document 1, while waste pieces obtained by cutting and reducing the volume of radioactive waste are stored in at least one storage container to produce waste bodies, the amount of waste bodies cannot be reduced. As a result, in the invention of Patent Document 1, the number of waste bodies to be produced increases unnecessarily, and thus the space of a storage building for storing waste bodies until the final disposal is not fully utilized. Furthermore, with the unnecessarily large number of waste bodies being produced, the cost for transporting waste bodies to the storage building also increases.
Furthermore, the cutting volume reducing method of Patent Document 2 is not flexible, for radioactive waste needs to be cut out in accordance with the capacity of the storage container (so that the segments are not too small nor too large compared to the capacity of the storage container), which limits the manner of cutting considerably. Furthermore, radioactive waste with an extremely high radiation level, such as core structure, should not be pulverized into small pieces (e.g. particles), to prevent radioactive contamination from spreading, and thus it is difficult to apply the cutting volume reduction method of Patent Document 3.
In view of the above, an object of at least one embodiment of the present invention is to provide a method for determining conditions for accommodating in a container, by accommodating a plurality of waste pieces efficiently in a storage container to reduce the necessary number of storage containers while satisfying physical limiting conditions required for each waste body, an accommodation method for accommodating the plurality of pieces in a storage container in accordance with the method for determining conditions for accommodating in a container, and a waste body obtained by the method.
(1) In at least one embodiment of the present invention, a container accommodation condition determination method of determining an accommodation condition for accommodating a plurality of waste pieces, obtained by at least cutting radioactive waste, into at least one storage container, for obtaining at least one waste body by accommodating the plurality of waste pieces into the at least one storage container, comprises: a step of, assuming, for each of a plurality of arrangement condition candidates specifying the storage container in which each of the waste pieces is to be stored and an accommodation position inside the storage container, that the waste pieces are arranged inside the storage container in accordance with the arrangement condition candidate, selecting at least one of the arrangement condition candidates which satisfy a limiting condition required for the waste body in each of the storage containers; a step of calculating a necessary storage container number which is the number of the storage container required to accommodate the plurality of waste pieces in accordance with the selected arrangement condition candidate; and a step of specifying the arrangement condition candidate such that the necessary storage container number is minimum.
Accordingly, at least in an embodiment of the present invention, the storage container in which each waste piece is to be stored and an accommodation position in the storage container are defined by the arrangement condition candidate. Further, in at least one embodiment of the present invention, from among the plurality of arrangement condition candidates, at least one arrangement condition candidate satisfying the limiting condition is selected, and the arrangement condition candidate capable of reducing the number storage containers required to accommodate the plurality of waste pieces is determined as the accommodation condition for accommodating waste pieces in the storage container. The accommodation for the waste pieces obtained as described is a condition among the plurality of arrangement condition candidates, which satisfies the limiting condition of each waste body and is associated with the smallest necessary storage container number.
Therefore, according to at least one embodiment of the present invention, it is possible to accommodate the plurality of waste pieces in the storage container efficiently, and to reduce the necessary number of storage containers, while satisfying the physical limiting condition required for each waste body.
(2) Furthermore, in some embodiments of the present invention, the above method (1) comprises, performing, for each of a plurality of cutting conditions for cutting the radioactive waste, the step of selecting the arrangement condition candidate and the step of calculating the necessary storage container number, and specifying a combination of the cutting condition and the arrangement condition candidate such that the necessary storage container number is minimum.
As described above, according to the above configuration (2), it is possible to define various cutting manners for cutting the radioactive waste to obtain the plurality of waste pieces as the plurality of cutting conditions, and calculate an accommodation condition capable of reducing the number of waste bodies obtained by accommodating the waste pieces in the storage containers for each of the plurality of cutting conditions. As a result, according to the above configuration (2), it is possible to specify the most efficient combination of a cutting condition and an arrangement condition, as an accommodation condition capable of reducing the number of waste bodies by accommodating the waste pieces in the storage containers efficiently.
(3) Furthermore, in some embodiments of the present invention, in the above method (1) or (2), the method further comprises a step of obtaining a dose distribution of the radioactive waste, and the step of selecting the arrangement condition candidate includes selecting the arrangement condition candidate satisfying the limiting condition which at least specifies that a surface dose rate of the waste body is not higher than a threshold on the basis of the dose distribution.
When discarding or storing the waste bodies, it may be necessary to ensure safety and efficiency. The above method (3) is beneficent in such cases. That is, according to the above method (3), the surface dose rate of each waste body is set to be not higher than the threshold on the basis of the dose distribution of the radioactive waste, and thereby it is possible to reduce the number of storage containers required, while ensuring safety and efficiency in discarding or storing the waste bodies.
(4) Furthermore, in some embodiments of the present invention, in the above method (1) or (2), the method further comprises a step of measuring a dose of each of the waste pieces, and the step of selecting the arrangement condition candidate may include selecting the arrangement condition candidate satisfying the limiting condition which at least specifies that a surface dose rate of the waste body is not higher than a threshold on the basis of the dose of the waste pieces.
When discarding or storing the waste bodies, it may be necessary to ensure safety and efficiency. The above method (4) is beneficent in such cases. That is, according to the above method (4), the surface dose rate of each waste body is set to be not higher than the threshold on the basis of the dose distribution of the radioactive waste, and thereby it is possible to reduce the number of storage containers required, while ensuring safety and efficiency in discarding or storing the waste bodies.
(5) Furthermore, in some embodiments of the present invention, in the above methods (1) to (4), the method further comprises a step of storing, in a database, characteristic descriptive information showing a characteristic of each of the plurality of waste pieces, and the step of selecting the arrangement condition candidate may include determining whether the limiting condition required for the waste body is satisfied in each of the storage containers when the waste pieces are arranged in the storage containers in accordance with the arrangement condition candidate, on the basis of the characteristic descriptive information stored in the database.
Accordingly, with the above configuration (5), the operation for selecting the arrangement condition candidate defining the arrangement manner for arranging the waste pieces in the storage container is performed on the basis of the characteristic descriptive information showing the characteristics of each waste piece and thereby it is possible to perform efficient volume reduction in accordance with the characteristics of each, waste piece.
(6) Furthermore, in some embodiments of the present invention, in the above method (5), the character specific information includes at least one of a shape, a weight, or a dose, of each of the waste pieces.
Accordingly, with the above configuration (6), it is possible to select the arrangement condition candidate taking into account the shape, weight, or dose of the waste pieces.
(7) Furthermore, in some embodiments of the present invention, in the above methods (1) to (6), the method further comprises a step of compressing a plurality of segments obtained by cutting the radioactive waste to shape the segments into the plurality of waste pieces having at least one kind of standardized shape.
Accordingly, with the above configuration (7), the waste pieces are accommodated into a storage container after shaping the plurality of waste pieces obtained by cutting the radioactive waste into waste piece having a standardized shape (including dimensions). Thus, with the above configuration (7), it is possible to considerably simplify the computation process for determining the accommodation condition for reducing the amount of waste bodies obtained by accommodating the waste pieces in the storage container. Furthermore, with the above configuration (7), by, designing the standardized shape appropriately, it is possible to calculate an accommodation condition such that it is possible to stuff the waste pieces into the storage container with smallest possible clearance.
(8) Furthermore in some embodiments of the present invention, in the above methods (1) to (7), the limiting condition required for the waste body includes a condition such that at least one of a weight, a surface dose rate, or a heat generation amount, of each of the waste bodies is within an allowable range.
To implement some embodiments of the present invention, it may be necessary to ensure safety and efficiency in works for transporting the waste bodies to a site for long-term storage. Even in such a case, with the above configuration (8), at least one of the dose rate, weight, or heat generation amount of each waste body is set to be within an allowable range on the basis of the dose distribution of the radioactive waste, and thereby it is possible to reduce the number of storage containers required, while ensuring safety and efficiency in the transportation works for the waste bodies.
(9) Furthermore, in some embodiments of the present invention, in the above methods (1) to (8), the plurality of arrangement condition candidates include at least one arrangement condition candidate specifying that, inside each of the storage containers, a first waste piece is accommodated in a first region disposed in a center section of the storage container and a second waste piece is disposed in a second region surrounding the first region in the storage container so as to envelope the first waste piece, the second waste piece having a lower dose than the first waste piece.
According to the above method (9), if the selected arrangement condition candidate defines an arrangement such that the low-dose second waste pieces envelop the high-dose first waste piece, it is possible to reduce the dose that reaches the surface of the waste body thanks to the function as the radiation insulator of the low-dose second waste pieces enveloping the high-dose first waste piece, even in a case where the high-dose first waste piece is accommodated inside the storage container. Thus, if the plurality of arrangement condition candidates include a candidate defining the arrangement manner of the waste pieces according to the above method (9), it is possible to increase the possibility of the arrangement condition candidate satisfying the limiting condition, even in a situation where few storage containers are available and a large number of high-dose waste pieces need to be accommodated in the containers. Thus, a great amount of high-dose waste pieces can be accommodated as compared to a typical accommodation method, and it is possible to increase the filling rate of the waste pieces inside the storage container, which makes it possible to reduce the number of waste bodies compared to a typical accommodation method.
(10) Furthermore, in some embodiments of the present invention, the method may comprises a step of accommodating the waste pieces inside the storage container in accordance with the accommodation condition determined by the container accommodation method determination method according to any one of the above methods (1) to (9) to obtain at least one waste body.
Accordingly, with the above configuration (10), by using the container accommodation condition determining method described in the above (1) to (9), it is possible to implement the embodiments of the present invention as a method of accommodating a plurality of waste pieces in at least one storage container.
(11) In at least one embodiment of the present invention, a method of obtaining at least one waste body by accommodating a plurality of waste pieces, obtained by at least cutting radioactive waste, into at least one storage container, comprises: a step of accommodating a first waste piece in a first region positioned in a center section of the storage container; and a step of accommodating a second waste piece in a second region surrounding the first region in the storage container such that the second waste piece envelops the first waste piece, the second waste piece having a lower dose than the first waste piece.
As described above, in at least one embodiment of the present invention, the relatively low-dose waste pieces are arranged so as to envelop, as a radiation insulator, the relatively high-dose waste piece accommodated in the middle of the storage container. Accordingly, if the selected arrangement condition candidate defines an arrangement such that the low-dose waste pieces envelop the high-dose waste piece, it is possible to reduce the dose that reaches the surface of the waste body thanks to the function as the radiation insulator of the low-dose waste pieces enveloping the high-dose waste piece disposed inside the storage container. Thus, if the plurality of arrangement condition candidates include a candidate defining the arrangement manner of the waste pieces according to the above method (11), it is possible to increase the possibility of the arrangement condition candidate satisfying the limiting condition, even in a situation where few storage containers are available and a large number of high-dose waste pieces need to be accommodated in the containers. Thus, a great amount of high-dose waste pieces can be accommodated as compared to a typical accommodation method, and it is possible to increase the filling rate of the waste pieces inside the storage container, which makes it possible to reduce the number of waste bodies compared to a typical accommodation method.
(12) In at least one embodiment of the present invention, a waste body obtained by accommodating a plurality of waste pieces obtained by at least cutting a radioactive waste into at least one storage container comprises: a first waste piece accommodated in a first region positioned in a center section of the storage container; and a second waste piece accommodated in a second region surrounding the first region in the storage container such that the second waste piece envelops the first waste piece, the second waste piece having a lower dose than the first waste piece.
As described above, the waste body according to the above embodiment (12) is produced such that the low-dose waste pieces are arranged so as to envelop, as a radiation insulator, the high-dose waste piece accommodated in the middle of the storage container. Thus, the waste body according to the above embodiment (12) can accommodate a greater number of high-dose waste pieces in a storage container with a high filling rate, as compared to a typical accommodation method. Furthermore, the waste body according to the above embodiment (12) includes low-dose waste pieces that function as a radiation insulator, surrounding a high-dose waste piece accommodated inside the storage container. Accordingly, the waste body according to the above embodiment (12) can reduce the surface dose rate and heat generation amount of the surface of the waste body effectively even if a high-dose waste piece is accommodated, which makes it possible to facilitate disposal works and storage works for the waste bodies.
According to at least one embodiment of the present invention, it is possible to accommodate the plurality of waste pieces in the storage container efficiently, and to reduce the necessary number of storage containers, while satisfying the physical limiting condition required for each waste body.
Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It is intended, however, that unless particularly specified, dimensions, materials, shapes, relative positions and the like of components described in the embodiments shall be interpreted as illustrative only and not intended to limit the scope of the present invention.
Furthermore, in the exemplary embodiment shown in
Next, with reference to
Herein,
As shown in
Normally, the waste pieces 900 each have a three-dimensional shape (including dimensions) that is random and not uniform. However, in
The limiting condition refers to restrictions related to the characteristics of the waste body 950, which are required to be satisfied by the waste body 950 as a whole. In an embodiment, the limiting condition includes a condition such that at least one of weight, surface dose rate, or heat generation amount, of each waste body 950 should fall within an allowable range. In yet another embodiment, the limiting condition includes a condition such that all of weight, surface dose rate, and heat generation amount, of each waste body 950 should fall within an allowable range.
In some embodiments, assuming that the waste pieces 900 are arranged in the storage containers 91 in accordance with each of the N arrangement condition candidates Ai (1≤i≤N, where N is an integer not less than two) as shown in
In the exemplary embodiment shown in
In some embodiments, when selecting arrangement condition candidates, j (1≤j≤N) arrangement condition candidates are selected, which satisfy the limiting condition that specifies at least the surface dose rate of the waste body 950 (950A to 950C) is not higher than a threshold, on the basis of the dose distribution of the radioactive waste 9. Accordingly, it is possible to reduce the necessary number of storage containers 91 (91A to 91C) while ensuring safety and efficiency of the transportation work for the waste body 950 (950A to 950C).
The method for obtaining the dose distribution of the radioactive waste 9 is not particularly limited. For instance, the dose distribution may be obtained from a result of measurement of the dose distribution of the radioactive waste 9 at a plurality of measurement points, or may be estimated on the basis of the previous radiation exposure history of the radioactive waste 9.
After selecting j arrangement condition candidates A′j satisfying the limiting condition, subsequently, the number X of storage containers necessary (necessary storage container number) for accommodation of the plurality of waste pieces 900 according to each of the arrangement condition candidates A′j (1≤j≤N) is calculated. The necessary storage container number X is calculated for each of the arrangement condition candidates satisfying the limiting condition.
After calculating the necessary storage container number X for each of the arrangement condition candidates satisfying the limiting condition, an arrangement condition candidate associated with the smallest necessary storage container number X is specified.
Accordingly, the obtained arrangement condition candidate one of the i arrangement condition candidates A that have been studied, which satisfies the limiting condition and is associated with the smallest necessary storage container number X. Therefore, according to the above described method, it is possible to accommodate the plurality of waste pieces 900 in the storage container 91 efficiently, and to reduce the necessary storage container number X, which is the number of storage containers 91 required, while satisfying the physical limiting condition required for each waste body.
In the above described method for determining an accommodation condition, a plurality of cutting conditions may be selected for the radioactive waste 9, which contributes to reduction of the necessary storage container number X. Hereinafter, with reference to
The high dose region 90 in
In some embodiments, assuming a plurality of (M) cutting conditions Bk that specify cutting patterns for cutting the radioactive waste 9 to obtain the plurality of waste pieces 900 (900A to 900C) (1≤k≤M, where M is an integer not less than two), for each of the plurality of cutting conditions Bk, the step of selecting an arrangement condition candidate Aj and the step of calculating the necessary storage container number X are performed, and a combination of a cutting condition B and an arrangement condition candidate A such that the necessary storage container number X is minimum is specified.
For instance, in the embodiment shown in
As described above, according to the method described above with reference to
In some embodiments, the above method of determining an accommodation condition in a container further includes a step of obtaining the dose distribution of the radioactive waste 9. In the step of selecting an arrangement condition candidate A′j, an arrangement condition candidate A′j that satisfies the limiting condition defining at least that the surface dose rate of the waste body 950 (950A to 950C) is not higher than the threshold may be selected, on the basis of the obtained dose distribution.
When discarding or storing the waste bodies 950 (950A to 950C), it may be necessary to ensure safety and efficiency. The above method is beneficent in such cases. That is, according to the above method, the surface dose rate of each waste body 950 is set to be not higher than the threshold on the basis of the dose distribution of the radioactive waste 9, and thereby it is possible to reduce the number of necessary storage container number X, which is a number of storage containers required, while ensuring safety and efficiency in discarding or storing the waste body 950.
In some embodiments, the above method of determining an accommodation condition in a container further includes a step of measuring the dose distribution of the radioactive waste 9. In the step of selecting an arrangement condition candidate A′j, an arrangement condition candidate A′j that satisfies the limiting condition defining at least that the surface dose rate of the waste body 950 (950A to 950C) is not higher than the threshold may be selected, on the basis of the measured dose distribution.
When discarding or storing the waste bodies 950 (950A to 950C), it may be necessary to ensure safety and efficiency. The above method is beneficent in such cases. That is, according to the above method, the surface dose rate of each waste body 950 is set to be not higher than the threshold on the basis of the dose distribution of the radioactive waste 9, and thereby it is possible to reduce the number of necessary storage container number X, which is a number of storage containers required, while ensuring safety and efficiency in discarding or storing the waste bodies 950.
Accordingly, in at least one embodiment of the present invention, the storage container 91 in which each waste piece 900 is to be stored and an accommodation position in the storage container are defined by the arrangement condition candidate A. Further, in at least one embodiment of the present invention, from among the plurality of arrangement condition candidates Ai (1≤i≤N), as an accommodation condition for accommodating waste pieces into a storage container, the arrangement condition candidate A0 is determined, which is capable of reducing the necessary storage container number X, which is a number of storage containers 9 required to accommodate the plurality of waste pieces 900. Thus, according to at least one embodiment of the present invention, when accommodating the plurality of waste pieces 900 into at least one storage container 91 to obtain at least one waste body 950, it is possible to calculate an accommodation condition capable of reducing the amount of waste bodies 950.
In an embodiment, on the basis of the dose distribution, the arrangement condition candidate Aj satisfying the limiting condition which defines at least that the surface dose rate of the waste body 950 is not higher than the threshold may be selected as follows.
For instance, for each case in which the radioactive waste 9 is cut in accordance with the plurality of cutting conditions Bk (1≤k≤M, where M is an integer not less than two), information on the dose of each waste piece 900 is obtained. At this time, the dose information of each waste piece 900 is managed in association with the corresponding cutting condition Bk. Accordingly, assuming that the plurality of waste pieces 900 cut under the particular cutting condition Bk are accommodated in the storage container 91 in accordance with the particular arrangement condition candidate A′j, it is possible to obtain the surface dose rate of the waste body 950 by combining the dose information per waste piece 900 for the plurality of waste pieces 900. Furthermore, it is determined whether the surface dose rate of the waste body 950 is not higher than the threshold, and thereby it is determined whether the arrangement condition candidate A′j satisfies the above limiting condition.
In an embodiment, the above described container accommodation condition determining method may be performed by using a computer program executed on a computer. For instance, in an embodiment, the above described container accommodation condition determining method may be performed by using a computer program 124 executed on a computer system 10 shown in
The computer system 10 includes a computer 100a, a database 210a, and a control console 220 connected mutually to one another so as to be communicable via a local area network 230a. The computer 100a executes the computer program 124 in response to command from the control console 220a. The database 201a identifies each of one or more waste bodies 950 with identification information of a tug associated with each waste body 950, and stores characteristic descriptive information describing the physical characteristic condition of each waste body 950 in association with each waste body 950. The control console 220a may function as a terminal for a system user to provide command and information for the computer program 124 on the computer 100a, and for showing outputs of the computer program 124 on a display.
The computer 100a includes a CPU 110a, a main memory 120a, and an interface 130a. The CPU 110a reads and runs the computer program 124 stored on the main memory 120a. The main memory 120a stores information related to the plurality of (N) cutting conditions 121k (1≤k≤N)and the plurality of (M) arrangement condition candidates 122i (1≤i≤M). Furthermore, the main memory 120a stores data representing information other than the above in a temporary storage region 123a. The interface 130a provides a communication path for sending and receiving data and control signals between the CPU 110a, the main memory 120a, and the local area network 230a. The plurality of program modules or function constituting the computer program 124 may be read by the CPU 110a from the main memory 120a and executed as function modules 11a to 118a.
The input/output and main control part 111a functions as an input/output part for the above described function modules 112a to 118a to send and receive data and command signals between the main memory 120a, the database 210a, and the control console 220a. Furthermore, the input/output and main control part 111a has a role to control the overall flow of the series of processing operations executed by the above described function modules 112a to 118a. For instance, the series of processing operations executed by the above described modules 112a to 118a need to be executed repeatedly by loop control until finding a combination of a cutting condition and an arrangement condition candidate such that the necessary number of the storage container is minimum when all of the waste pieces are accommodated. Thus, the input/output and main control part 111a calls out the above described function modules 112a to 118a repeatedly for the number of repetitive executions controlled by the above loop control.
The arrangement condition candidate generating part 113a generates each of the plurality of arrangement condition candidates 122i (1≤i≤M) defining the storage container 91 in which each of the waste pieces 900 is to be stored and the accommodation position inside the storage container 91. Next, the arrangement condition candidate selecting part 114a having received the plurality of arrangement condition candidates 122i (1≤i≤M) generated by the arrangement condition candidate generating part 113a selects, assuming that the waste pieces 900 are arranged inside the storage container 91 in accordance with the plurality of arrangement condition candidates 122i (1≤i≤M), one or more arrangement condition candidates 122j (1≤j≤M) that satisfy the limiting condition required for the waste body, in each storage container 91.
After receiving the selected one or more arrangement condition candidates 122j (1≤j≤M), the necessary storage container number calculation part 115a calculates the necessary storage container number X, which is the number of storage containers 91 required to accommodate the plurality of waste pieces 900 in accordance with the selected arrangement condition candidate 122j (1≤j≤M). After receiving the plurality of arrangement condition candidates 122j (1≤j≤M) and the necessary storage container number X calculated for each arrangement condition from the necessary storage container number calculation part 115a, the optimum arrangement condition candidate specifying part 116a specifies the arrangement condition candidate 122(0) such that the necessary storage container number X is minimum, and outputs the same to the input/output and main control part 111a.
In at least one embodiment, the above process executed by the function modules 113a to 118a may be executed for each of the plurality of cutting conditions 121k (1≤k≤N) of the radioactive waste. In such an embodiment, the cutting condition obtaining part 112a obtains the plurality of cutting conditions 121k (1≤k≤N) and stores the obtained cutting conditions 121k (1≤k≤N) in the main memory 120a. Next, the process for selecting the arrangement condition candidate 122j (1≤j≤M) and the process for calculating the necessary storage container number X are obtained by the cutting condition obtaining part 112a, and repeatedly executed for each of the plurality of cutting conditions 121k (1≤k≤N) stored in the main memory 120a. As a result, the optimum arrangement condition candidate specifying part 116a specifies a combination of the cutting condition 121k (1≤k≤N) and the arrangement condition candidate 122j (1≤j≤M) such that the necessary storage container number X is minimum.
In at least one embodiment, the cutting condition obtaining part 112a may obtain the characteristic descriptive information representing the characteristics of each of the plurality of waste pieces 900 on the basis of a measurement result of the dose distribution of the radioactive waste 9, and store the same in the database 210a. Furthermore, in at least one embodiment, in the process of selecting the arrangement condition candidate 122j (1≤j≤M), the following operation may be executed. First, the characteristic descriptive information obtaining part 118a is instructed to obtain the characteristic descriptive information stored in the database 210a. Next, on the basis of the obtained characteristic descriptive information, the arrangement condition candidate selecting part 114a determines whether the limiting condition required for each waste body 950 is satisfied in each of the storage containers 91, in a case where the waste pieces 900 are arranged inside the storage container 91 in accordance with the arrangement condition candidate 122j (1≤j≤M).
Hereinafter, the flow of the series of processing operations executed by the function modules 111a to 118a shown in
Next, the cutting condition obtaining part 112a obtains the plurality of cutting conditions 121k (1≤k≤N) of the radioactive waste referring to the dose distribution measurement data, and stores the obtained cutting conditions 121k (1≤k≤N) in the main memory 120a. The arrangement condition candidate generating part 113a reads out the plurality of cutting conditions 121k (1≤k≤N) from the main memory 120a, and selects one unselected cutting condition 121′ from among the plurality of cutting conditions 121k (1≤k≤N). Next, in step S803, the arrangement condition candidate generating part 113a generates one arrangement condition candidate 122j on the basis of the selected cutting condition 121′, and stores the same in the main memory 120a.
Next, in step S804, the arrangement condition candidate selecting part 114a reads out the arrangement condition candidate 122j from the main memory 120a, and determines whether the arrangement condition candidate 122j satisfies the limiting condition required for each waste body, by using the characteristic descriptive information of each waste piece obtained from the arrangement condition candidate generating part 113a. Next, in the step S 805, if the arrangement condition candidate selecting part 114a determines that the arrangement condition candidate 122j satisfies the predetermined limiting condition, the process advances to the step S806 in
In the step S806 of
In the step S807 of
In the step S808 of
In the step S809, the optimum arrangement condition candidate specifying part 116a receives the plurality of arrangement condition candidates and the necessary storage container number X calculated for each arrangement condition from the necessary storage container number calculation part 115a, for all of the plurality of cutting conditions 121k (1≤k≤N). Next, the optimum arrangement condition candidate specifying part 116a specifies an efficient combination of an arrangement condition candidate and a cutting condition such that the necessary number of the storage container 91 is minimum, from among the necessary storage container numbers X calculated for each of the arrangement condition candidates for each of the plurality of cutting conditions 121k (1≤k≤N). Finally, the optimum arrangement condition candidate specifying part 116a outputs the specified optimum combination of the arrangement condition candidate and the cutting condition to the input/output and main control part 111a.
Next, a modified example for implementing the one or more embodiments described herein with partial correction will be described with reference to
Thus, in the embodiment shown in
In the exemplary embodiment shown in
In an exemplary embodiment, for example, a standardized shape may a shape having dimensions of length, width, and height obtained by dividing the length of the long side, the length of the short side, and the depth, respectively, of the accommodation space cross section inside the storage container 91 by an appropriate integer, rounding down the fractions. Furthermore, as an example of the method of determining the standardized shape, the waste pieces 910 may be shaped by compression so that the length, width, and height dimensions of the waste pieces 910 become the dimensions obtained by dividing the length of the long side the length of the short side, and the depth, respectively, of the accommodation space cross section inside the storage container 91 by an appropriate integer, rounding down the fractions. More specifically, provided that Lx, Ly, and Lz are the length of the long side, the length of the short side, and the depth of the accommodation space cross section inside the storage container 91, respectively, appropriate integers α, β, and γ may be used to calculate the dimensions lx, ly, and lz, of the length, width, and height of the standardized shape.
(Expression 1)
lx=└Lx/α┘, ly=└Ly/β┘, lz=└Lz/γ┘ (1)
In an exemplary embodiment, the above described compression shaping process may be performed by a cutting process, a compression process, a melting process, or combination of the above, for the plurality of segments 940 cut out from the radioactive waste 9. In an embodiment, the radioactive waste 9 may include a reactor internal structure 9a cut by a cutting tool. In an embodiment, the plurality of segments 940 obtained by cutting the radioactive waste may be sorted according to the radiation level, by the sorter 94 shown in
In
Furthermore, in a case where the plurality of segments 940 obtained by cutting the radioactive waste are sorted by dose as in the modified embodiment shown in
Therefore, according to the embodiment shown in
In an embodiment, the above embodiment shown in
In the computer system 20 shown in
Hereinafter, the overall process flow of the embodiment shown in
The process of the flowchart in
Next, the process advances to the step S1203, and a tag is applied to each of the plurality of waste pieces 910. The tag applied to each of the plurality of waste pieces 910 includes records of identification information for specifically identifying each of the waste pieces 910. Next, the process advances to the step S1204, and the weight per waste piece is actually measured for each of the plurality of waste pieces. Furthermore, if two or more types of standardized shape are defined, it is also determined which type of standardized shape the plurality of waste pieces have. Next, the process advances to the step S1205, and the surface dose rate and heat generation amount per waste piece are actually measured for each of the plurality of waste pieces. Next, the process advances to the step s1206, and information is recorded on the database 210b, which represents the weight, type of standardized shape, surface dose rate, and heat generation amount, per waste piece actually measured or determined as described above, for each of the plurality of waste pieces. At this time, the information representing the weight, type of standardized shape, surface dose rate, and heat generation amount, per waste piece is recorded on the database 201b in association with the identification information per waste piece recorded on the tag attached to each of the plurality of waste pieces 910.
Next, the process advances to the step S1207 and so on. The steps S1207 to S1211 are similar to the steps S803 to S807 in
Another embodiment of the present invention will now be described in reference to
Accordingly, if the selected arrangement condition candidate defines an arrangement (
Furthermore, in the container accommodation condition determining method according to the embodiment with reference to
Accordingly, if the selected arrangement condition candidate defines an arrangement (
| Number | Date | Country | Kind |
|---|---|---|---|
| 2015-204470 | Oct 2015 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2016/074890 | 8/25/2016 | WO | 00 |
