JP6074277B2 - Land division, storage method, division method - Google Patents

Description

  The present invention relates to a land division body for dividing land, a radioactive material storage method and a division method using the same.

  In areas where radioactive materials have caused environmental pollution, it is necessary to decontaminate and remove the contaminants. Contaminants removed by decontamination work are stored while moving to other locations such as decontamination sites, on-site storage locations, temporary storage locations, and intermediate storage facilities until final processing is performed so as not to affect the environment. The

  As a safety measure for storage locations, it is necessary to appropriately control the additional exposure dose to the public. Therefore, after the contaminants are enclosed in containers, the surroundings of the storage area are surrounded by ropes in order to shield the radiation by embedding these containers and shielding the radiation. In addition, in order to confirm that the additional exposure dose is appropriately controlled, the radiation dose around the storage location is monitored from the time when the contaminant is brought into the storage location. This is necessary not only for the purpose of safety measures but also from the viewpoint of explanation to the surrounding residents.

  For radiation dose monitoring, workers bring survey meters, observe fixed points around the storage location several times a day, install monitoring posts, and measure at one point around the storage location. It was normal to go.

  On the other hand, as a radiation dose measurement technique, a measurement method using an optical fiber using a scintillation effect of radiation is also known, as in Patent Documents 1 and 2.

Japanese Patent Laid-Open No. 10-186034 Japanese Patent Laid-Open No. 11-125679

  In the conventional radiation dose monitoring method, the measurement position of the radiation dose is only a limited point around the storage location, and the radiation dose in the entire surroundings cannot be properly grasped. In particular, if the amount of radiation in the entire area around the storage location can be grasped continuously from the start of the introduction of contaminants at the time of construction of the storage location, the radiation dose due to the introduction of contaminants, radiation due to the installation of embankments, etc. It is preferable from the viewpoint of developing a sense of security because the process of decreasing the amount can be explained to the surrounding residents by the amount of radiation around the storage area.

  On the other hand, a wide range of radiation dose can be measured by using an optical fiber as described above, but the measurement method using an optical fiber can be used to measure the radiation dose temporarily as in conventional survey meters so far. However, even if the radiation dose is measured continuously, the radiation dose is measured by placing it in a radioactive substance storage container as in Patent Document 2.

  Furthermore, although a fence is provided at the storage location, the provision of the fence to separate the inside and the outside needs to be shown to be safe at least at the position of the fence. In this respect, it is desirable that the radiation dose can be measured at the position of the fence. However, in practice, measurement on the fence is difficult, and there is a problem that the position of the fence and the measurement position of the radiation dose do not match.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a land segment that can measure radiation dose at a boundary position over time.

A first invention for achieving the above-described object is a land partitioning body that divides an inner and outer area of land, and is provided along a boundary position that divides the inner and outer area, and a sensor for measuring a radiation dose; An information processing apparatus connected to the sensor and for recording a radiation dose measured by the sensor, wherein the sensor is a linear object continuous along the boundary position and has a predetermined height by a support. It is a land division characterized by being supported by .

  In this way, the land area can be used to distinguish between the inner and outer areas of the land, and the radiation dose covering the entire inner area along the boundary position of the land area can be measured over time. It is possible to manage the radioactive material safely by grasping the fluctuation of the radiation dose. By separating the land by the land classification body, it is possible to prevent outsiders from approaching, and by matching the boundary position with the radiation dose measurement position, the safety at the boundary position is guaranteed based on the radiation dose at the boundary position. It can give a sense of security to the local residents.

Since the measurement height of radiological amount is defined and supports the sensor as described above to a predetermined height, it is suitable for measuring the radiation dose. The use of a continuous linear sensor is also preferable in terms of completeness of radiation dose measurement positions and prevention of outsider access.

An optical fiber is preferably used for the sensor.
By using an optical fiber as a sensor, it is possible to easily configure a land classification body that measures the radiation dose at the boundary position while sorting the land.

The land segment of the first invention preferably further includes an alarm device that generates an alarm when the radiation dose measured by the sensor exceeds a predetermined threshold value.
As a result, when the radiation dose increases, it is possible to notify the administrator or the like, and it is possible to manage the radioactive material more safely by moving the land sections and expanding the internal area accordingly.

The land segment of the first invention is preferably arranged so as to surround the accumulation point of the substance that emits radiation. Or it is also desirable to arrange | position so that the area where decontamination was completed and the area where decontamination was not completed may be divided.
In such storage locations and areas, strict management of radiation dose is required and the understanding of the surrounding residents is particularly necessary.

A second aspect of the present invention is a land division body that divides an inner and outer area of land, and is provided along a boundary position that divides the inner and outer area, and is connected to the sensor, and is connected to the sensor. A storage method for storing a substance that emits radiation using an information processing unit that records radiation dose measured in step (a ), and collecting the substance that emits radiation. A step (a) of arranging the area so as to surround a part, and a step of rearranging the land section so as to reduce or enlarge the internal area of the land section according to the radiation dose from the substance ( and b), and the radiation dose is measured by the sensor of the land division body.

  As described above, the radioactive material can be safely managed as described above by surrounding the radioactive material while measuring the radiation dose using the land division body. Land sections can be relocated flexibly, so that the radiation dose at the boundary position does not always exceed the threshold based on safety standards, etc., while narrowing or expanding the internal area according to the measured radiation dose. Boundary positions that can be placed and whose safety is guaranteed by the land divisions can be specified.

In the storage method of the second invention, prior to the step (a), a substance that emits radiation is measured in the land classification while measuring a radiation dose with the sensor in a state where a part of the land classification body is opened. It is desirable to further include a step (c) for carrying into the internal region of the body.
In this way, it is possible to manage the radioactive material more safely by continuously measuring the radiation dose from the start of carrying in the radioactive material.

A third aspect of the present invention is a land division body that divides an inner and outer area of a land, and is provided along a boundary position that divides the inner and outer area, and is connected to the sensor, and is connected to the sensor. (A) demarcating an area where decontamination has been completed and an area where decontamination has not been completed, using an information processing device which records the radiation dose measured in And (b) rearranging the land segments according to the progress of the method, and measuring the radiation dose by a sensor of the land segments.

  As a result, the boundary between the two areas can be clarified, and at that boundary position, the radiation dose can be reliably guaranteed to be below a certain threshold value, and can be shown visually. . In addition, since the progress of decontamination can be shown in real time, the situation can be explained to the surrounding residents.

  ADVANTAGE OF THE INVENTION According to this invention, the land division body etc. which can measure a radiation dose in a boundary position over time can be provided.

The figure which shows temporary storage 1 The figure which shows the optical fiber sensor 11 The figure which shows the radioactive material accumulation location 20 The figure which shows the storage method of the radioactive substance in temporary storage 1 Diagram showing fluctuations in radiation dose The figure shown about the division of the decontamination completion area 40 and the non-decontamination area 50 by the fence 10

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

[First Embodiment]
(1. Configuration of temporary storage 1)
Drawing 1 is a figure showing temporary storage 1 using fence 10 concerning an embodiment of a land division object of the present invention. As shown in FIG. 1 (a), the temporary storage 1 is configured by dividing a land into an inner and outer area by a fence 10 (land division body) and constructing a radioactive material accumulation point 20 in an inner area 100.

  The fence 10 includes an optical fiber sensor 11, a photomultiplier tube 13, a cable 14, a pile 15, a time wave height converter 17, an alarm 18, a PC 19, and the like.

  The optical fiber sensor 11 is a long linear object continuously arranged along the boundary position between the inner and outer regions, and is used for measuring the radiation dose using the scintillation effect of radiation. As shown in FIG. 2, in the optical fiber sensor 11, when radiation 22 is incident, the incident portion emits light as a light emitting unit 21 by a scintillation effect, and radiates light 21 a and 21 b toward both ends. Lights 21 a and 21 b propagate toward both ends while being reflected in the optical fiber sensor 11.

  The optical fiber sensor 11 has photomultiplier tubes 13 at both ends. Each photomultiplier tube 13 detects the light 21a and 21b, respectively. A time difference between the light beams 21 a and 21 b that reach the photomultiplier tubes 13 is generated according to the position of the incident portion (light emitting unit 21) of the radiation 22 in the length direction of the optical fiber sensor 11. The photomultiplier tube 13 converts the detected lights 21a and 21b into electric signals and amplifies them.

  The photomultiplier tubes 13 at both ends are each connected to a time wave height converter 17 via a cable 14. From each photomultiplier tube 13, the electrical signal is sent to the time wave height converter 17 via the cable 14.

  The time wave height converter 17 receives the electrical signal from each photomultiplier tube 13 and outputs the time difference at which the electrical signal is received to the PC 19 which is an information processing device.

  The PC 19 converts this time difference into a position in the length direction of the optical fiber sensor 11, and for each position in the length direction of the optical fiber sensor 11, the radiation is calculated from the detection frequency (counting rate) of the light 21a and 21b per unit time. Find the amount. The above measurement is performed continuously, and the PC 19 records the time change of the radiation dose at each position of the optical fiber sensor 11. The PC 19 can be realized by a general computer having a control unit, a storage unit, a display unit, a communication unit, and the like.

  Note that the measurement of the radiation dose by the scintillation effect of the optical fiber is also described in Patent Documents 1 and 2 and the like.

  The pile 15 is a support that supports the optical fiber sensor 11 at a predetermined height as shown in FIG. The supporting height is determined according to the radiation dose measurement standard. For example, since the radiation dose is often evaluated based on the air dose rate measured at a height of about 1 m from the ground surface, the height of the optical fiber sensor 11 is adjusted accordingly.

  In addition, an alarm 18 as a warning device is connected to the PC 19 so as to be communicable by wire or wirelessly. The alarm 18 is arranged at a place where an administrator or the like is present, and when the measured radiation dose exceeds a threshold value based on safety standards or the like, a sound is output as an alarm to that effect.

  FIG. 3 is a diagram showing the radioactive substance accumulation location 20. In the radioactive material accumulation location 20, a water shielding layer 201 a is formed on the ground surface 200 by a water shielding sheet or the like. A protective layer 202 made of a protective mat or the like is provided on the water shielding layer 201a in order to prevent the water shielding layer 201a from being damaged.

  On the protective layer 202, a container 203 filled with a radioactive substance is arranged, and a bank 205 is constructed thereon. The embankment 205 is covered with a water shielding layer 201 b such as a water shielding sheet, and an end of the water shielding layer 201 b is fixed to the ground 200 with a sandbag 207.

(2. Radioactive material storage method)
Next, with reference to FIG. 4, 5, the storage method of the radioactive substance using the fence 10 is demonstrated. FIG. 4 is a diagram showing the flow of the radioactive substance storage method, and FIG. 5 is a diagram schematically showing the measurement results of the radiation dose over time.

  In this embodiment, first, as shown in FIG. 4A, the container 203 enclosing the radioactive substance and the radioactive substance accumulation point 20 are constructed while measuring the radiation dose with both ends of the fence 10 opened. Materials necessary for this are carried into the internal region 100 using the vehicle 30 or the like, and construction of the radioactive material accumulation point 20 is started as described above. At the start of loading of the container 203, the radiation dose (air dose rate) is in a high state as shown in “loading start” in FIG.

  The containers 203 are successively carried into the inner region 100 and are sequentially disposed on the protective layer 202 as described above. On the other hand, the reason why the radiation dose does not increase after the start of delivery as shown in FIG. 5 is that the container 203 arranged outside shields the radiation emitted from the radioactive substance in the inner container 203.

  Thereafter, when the radioactive material accumulation portion 20 is constructed while continuing the measurement of the radiation dose, when the embankment 205 is constructed on the container 203, the embankment 205 serves as a shield, and “ The radiation dose decreases as shown in “Installation of shielding body (banking)”. When the radiation dose is thus reduced, the fence 10 is moved and rearranged as shown in FIG. 4B, and the radiation dose measured by the optical fiber sensor 11 of the fence 10 is determined in advance by safety standards or the like. The inner region 100 is narrowed on condition that the threshold is not exceeded.

  And if construction of the radioactive material accumulation | aggregation location 20 is completed, as shown in FIG.4 (c), both ends of the fence 10 will be closed.

  In the present embodiment, the radiation dose is continuously measured by the optical fiber sensor 11 of the fence 10 thereafter. Since the radiation dose gradually decreases, the fence 10 is moved as shown in FIG. 4D at an appropriate time according to this, and the inner region 100 is further narrowed as described above.

  In some cases, the radiation dose may increase. At this time, if at least one point in the length direction of the optical fiber sensor 11 has a radiation dose that exceeds a threshold value determined in advance by a safety standard or the like, an alarm can be generated by the alarm 18 to notify an administrator or the like. . In response to this, the manager or the like can move the fence 10 and rearrange the fence 10 to expand the internal region 100 to a position where the radiation dose is equal to or less than the threshold value.

  In this way, in the temporary storage 1, the inside and outside areas of the land are classified using the fence 10 and the radiation dose at the boundary position is measured continuously. And the arrangement | positioning of the fence 10 is performed flexibly according to the measured radiation dose, The internal area | region 100 is narrowed or expanded, and a radioactive substance is stored.

  As described above, in this embodiment, the fence 10 can be used to distinguish the inside / outside area of the land so that the radiation dose covering the entire periphery of the inner area 100 along the boundary position by the fence 10 can be identified. Temporal measurement can be performed, and radioactive materials can be managed safely by grasping fluctuations in radiation dose. By separating the land with the fence 10, it is possible to prevent outsiders from approaching, and by matching the boundary position with the radiation dose measurement position, safety at the boundary position can be guaranteed based on the radiation dose at the boundary position. , Can give a sense of security to the surrounding residents.

  The storage location of the radioactive substance is not limited to the temporary storage place 1 as in the present embodiment, but a place where the contaminant containing the radioactive substance is stored before the final processing is performed, for example, a storage place on site. It can be applied to various places such as intermediate storage facilities.

  Furthermore, the application of the fence 10 is not necessarily limited to such a storage place, but in such a storage place, strict management of the radiation dose is required and the understanding of the surrounding residents is particularly necessary. It is particularly suitable for using the fence 10 described above.

  Moreover, in the fence 10, since the linear optical fiber sensor 11 which continues along a boundary position is used and this is supported by the pile 15, it can be arrange | positioned according to prescription | regulation of the measurement height of a radiation dose. Suitable for measurement of radiation dose. Furthermore, it is also preferable in terms of completeness of radiation dose measurement positions and prevention of outsider access.

  However, the sensor is not necessarily limited to the linear optical fiber sensor 11. The sensor may be any sensor that can measure the radiation dose, and may be arranged at a predetermined pitch along the boundary position. However, by using the linear optical fiber sensor 11, the fence 10 that measures the radiation dose at the boundary position while dividing the land continuously can be easily configured.

  In addition, in this embodiment, the pile 15 is used as a support body which supports the optical fiber sensor 11, However, Other structures are applicable as a support body. However, the use of the pile 15 has an advantage that the moving of the fence 10 can be easily performed.

  Moreover, since the fence 10 of this embodiment is provided with the alarm 18 as a warning device, it can notify an administrator or the like when the radiation dose increases, and is safer by expanding the internal region 100 in accordance with this. Radioactive material can be managed. In the present embodiment, the alarm 18 is alarmed by sound output. However, the alarm device is a computer or a portable terminal connected to the PC 19 via a network or the like, and the alarm is generated by displaying the screen. You may make it do.

  Further, in the above-described radioactive substance storage method, the fence 10 is made flexible so that the radiation dose at the boundary position does not always exceed the threshold value while narrowing or expanding the internal region 100 according to the measured radiation dose. The boundary position where safety can be guaranteed by the fence 10 can be clearly shown. In addition, it is possible to manage the radioactive material more safely by continuously measuring the radiation dose from the start of carrying in the radioactive material.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. 2nd Embodiment is an example arrange | positioned so that the fence 10 demonstrated above may divide the decontamination completion area 40 and the non-decontamination area 50. FIG.

  In the present embodiment, as shown in FIG. 6A, among the decontamination target areas 30 to be decontaminated, the decontamination completion area 40 in which the decontamination is completed and the radiation dose becomes a certain threshold value or less, Along the boundary 41 with the non-decontaminated area 50 where the decontamination is not completed or decontamination is not completed and the radiation dose exceeds the above threshold, the measured radiation dose exceeds the above threshold. The fence 10 is arrange | positioned in the position which does not exceed. And the radiation dose is measured continuously by this fence 10.

  As the decontamination progresses, the decontamination completion area 40 changes and expands as shown in FIG. 6B, but in this embodiment, the fence 10 is moved as appropriate in accordance with the expansion of the decontamination completion area 40. Then, the fence 10 can be provided along the boundary 41 between the decontamination completion area 40 and the non-decontamination area 50 at each stage of decontamination. At this time, it is confirmed that the radiation dose measured by the fence 10 does not exceed the above threshold.

  As described above, in the second embodiment, the fence 10 is disposed at the boundary 41 between the decontamination completed area 40 where the decontamination is completed and the radiation dose is equal to or less than the threshold, and the uncontaminated area 50 where the decontamination is not completed. By applying, effects similar to those of the first embodiment can be obtained. In other words, the boundary between the two areas is clarified, and it is possible to guarantee that the radiation dose is surely below a certain threshold at the boundary position and to show it visually, so it is possible to give a sense of security to the surrounding residents. Moreover, since the progress of decontamination can be shown in real time, the situation can be explained to the surrounding residents.

  As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

1: Temporary storage 10: Fence 11: Optical fiber sensor 15: Pile 18: Alarm 19: PC
20: Radioactive material accumulation location 22: Radiation 30: Decontamination target area 40: Decontamination completion area 41: Boundary 50: Uncontaminated area 100: Inner area 203: Container

Claims (8)

A land classifier that divides the land's internal and external areas,
A sensor for measuring a radiation dose provided along a boundary position that divides the inner and outer regions;
An information processing apparatus connected to the sensor and recording a radiation dose measured by the sensor;
Equipped with,
The sensor is a linear object that is continuous along the boundary position, and is supported at a predetermined height by a support . The land division according to claim 1 , wherein an optical fiber is used for the sensor. The land division according to claim 1 or 2, further comprising an alarm device that generates an alarm when a radiation dose measured by the sensor exceeds a predetermined threshold. The land segment according to any one of claims 1 to 3 , wherein the land segment is disposed so as to surround an accumulation site of a substance that emits radiation. Land segment body according to area decontamination decontamination has been completed is disposed so as to partition the areas that have not completed the claim 1, wherein in any one of claims 3. A land classifier that divides the land's internal and external areas,
A sensor for measuring a radiation dose provided along a boundary position that divides the inner and outer regions;
An information processing apparatus connected to the sensor and recording a radiation dose measured by the sensor;
A storage method for storing a substance that emits radiation using a land division comprising
A step (a) of arranging the land segment so as to surround an accumulation site of a substance that emits radiation;
Repositioning the land segment to reduce or increase the internal area of the land segment, depending on the radiation dose from the material, and (b)
Comprising
A storage method, wherein the radiation dose is measured by a sensor of the land segment. Before the step (a), in a state in which a part of the land segment is opened, while the radiation dose is measured by the sensor, the substance that emits the radiation is carried into an internal region of the land segment ( The storage method according to claim 6 , further comprising c). A land classifier that divides the land's internal and external areas,
A sensor for measuring a radiation dose provided along a boundary position that divides the inner and outer regions;
An information processing apparatus connected to the sensor and recording a radiation dose measured by the sensor;
(A) partitioning the area where decontamination has been completed and the area where decontamination has not been completed, using a land segment comprising
(B) rearranging the land segments according to the progress of decontamination;
Comprising
A division method characterized by measuring a radiation dose by a sensor of the land segment.

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