JPH09257937A - Radioactive quantity measuring method for radioactive solidified waste - Google Patents
Radioactive quantity measuring method for radioactive solidified wasteInfo
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- JPH09257937A JPH09257937A JP6477896A JP6477896A JPH09257937A JP H09257937 A JPH09257937 A JP H09257937A JP 6477896 A JP6477896 A JP 6477896A JP 6477896 A JP6477896 A JP 6477896A JP H09257937 A JPH09257937 A JP H09257937A
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- Prior art keywords
- radioactive
- count rate
- radioactivity
- radionuclide
- virtual
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、放射性物体に含ま
れる放射能量を測定する方法に関し、特にドラム缶等の
容器内に充填固化された放射性廃棄物の放射能量を測定
する方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the amount of radioactivity contained in a radioactive substance, and more particularly to a method for measuring the amount of radioactivity of radioactive waste packed and solidified in a container such as a drum.
【０００２】[0002]
【従来の技術】原子力発電所等の放射性物質取り扱い施
設では、放射能を帯びた金属片等が放射性廃棄物として
発生する。これらの放射性廃棄物はドラム缶等の容器に
収納され、これにセメント等が加えられて固化され、放
射性廃棄物固化体となって保管される。而して、この保
管に際してはその放射能量が測定され、その測定量に応
じて適切な保管方法が選択される。このような放射性廃
棄物固化体に含まれる放射能量を非破壊で測定する方法
としては、固化体からのガンマ線を高さ方向にはスライ
スに分割し、その横断面（径）方向にはコリメータの開
度を調整して測定することにより、固化体に含まれる放
射能量を求めるものが知られている（特開昭６３−２７
３０８４号公報）。この方法では、予め測定された固化
体の重量から算出した平均密度を基にコリメータ開口幅
を設定して測定している。又、固化体の高さ方向にはセ
グメントに分割し、固化体の径方向には外部線源を用い
て密度の違いによるガンマ線の吸収効果を求め、固化体
から放出されるガンマ線を密度の違いによる吸収効果を
補正して測定することにより、固化体の放射能量を測定
することも知られている（特開昭６２−８０５７８号公
報）。2. Description of the Related Art In radioactive material handling facilities such as nuclear power plants, radioactive metal fragments are generated as radioactive waste. These radioactive wastes are stored in a container such as a drum, and cement or the like is added to the container to solidify it, which is then stored as a solidified radioactive waste. Thus, during this storage, the amount of radioactivity is measured, and an appropriate storage method is selected according to the measured amount. As a method of nondestructively measuring the amount of radioactivity contained in such a solidified radioactive waste, gamma rays from the solidified body are divided into slices in the height direction, and the cross section (diameter) of the gamma ray is measured by a collimator. It is known that the amount of radioactivity contained in a solidified body is determined by adjusting the opening and measuring it (JP-A-63-27).
No. 3084). In this method, the collimator opening width is set and measured based on the average density calculated from the weight of the solidified body measured in advance. In addition, the height of the solidified body is divided into segments, and the gamma rays emitted from the solidified body are different in density in the radial direction of the solidified body using an external radiation source to obtain the gamma ray absorption effect. It is also known to measure the amount of radioactivity of the solidified body by correcting and measuring the absorption effect by (JP-A-62-80578).
【０００３】[0003]
【発明が解決しようとする課題】而して、金属片等をセ
メント等で固める場合、金属片等が大きい場合には容器
内で偏在することがあり、密度及び放射能の偏在が生ず
る。このため平均密度からコリメータの開口幅を調整す
る特開昭６３−２７３０８４号公報の測定方法では、精
度が良くないという問題がある。又、外部線源を用いる
特開昭６２−８０５７８号の方法では、固化体の密度が
大きくなると強い外部線源を必要とする問題がある。従
って、本発明の課題はドラム缶詰放射性廃棄物固化体に
密度及び放射能の偏在があっても、放射性核種別放射能
量を外部線源を用いず精度良く非破壊で測定する方法を
実現するにある。When a metal piece or the like is hardened with cement or the like, if the metal piece or the like is large, it may be unevenly distributed in the container, resulting in uneven distribution of density and radioactivity. Therefore, the measuring method disclosed in Japanese Patent Laid-Open No. 63-273084, which adjusts the opening width of the collimator based on the average density, has a problem that the accuracy is not good. Further, the method of JP-A-62-80578 using an external radiation source has a problem that a strong external radiation source is required when the density of the solidified body becomes large. Therefore, an object of the present invention is to realize a method for accurately and nondestructively measuring the radionuclide-specific radioactivity without the use of an external radiation source, even if the solidified waste of the drum canned radioactive waste has uneven distribution of density and radioactivity. is there.
【０００４】[0004]
【課題を解決するための手段】如上の課題を解決するた
め、本発明によれば、測定対象のドラム缶詰放射性廃棄
物固化体を回転昇降テーブル上に載せ、これを鉛直軸方
向に沿って複数のスライスに仮想的に分割し、その仮想
スライス毎に放出するガンマ線をコリメータ付きガンマ
線スペクトル検出器で検出するに際し、仮想スライス毎
に代表的放射性核種のエネルギの異なる２つの直接線ピ
ーク計数率を測定してそのピーク計数率比を求め、その
ピーク計数率比から各放射性核種毎の計数率の減衰率を
求め、各放射性核種について直接線計数率を測定し、そ
の直接線計数率を前記減衰率を用いて補正して仮想スラ
イス毎の各放射性核種量を測定し、その各放射性核種量
を積算してドラム缶詰放射性廃棄物固化体の放射能量と
する。或いは加えて前記仮想スライス毎にコリメータ開
度の異なるガンマ線測定を行って代表放射性核種の異な
るコリメータ開度での直接線のピーク計数率の比即ちコ
リメータ開度計数率比を求め、予め求められた相関関係
を基に前記ピーク計数率比と前記コリメータ開度計数率
比から仮想スライス毎に実効的密度と放射能位置を求
め、その実効的密度と放射能位置から各放射性核種の減
衰率を求め、各放射性核種について測定した直接線計数
率をその減衰率を用いて補正して仮想スライス毎の各放
射性核種量を測定し、その各放射性核種量を積算してド
ラム缶詰放射性廃棄物固化体の放射能量とする。尚異な
るエネルギのガンマ線を放出する放射性核種が存在しな
いときは、前述のピーク計数率比に代えてグロスの計数
率とピーク計数率の比を用いてもよい。In order to solve the above-mentioned problems, according to the present invention, the solidified canned radioactive waste solids of a drum to be measured are placed on a rotary lifting table, and a plurality of such solidified solid bodies are placed along the vertical axis. When the gamma ray emitted by each virtual slice is virtually detected by a gamma ray spectrum detector with a collimator, two direct ray peak count rates with different energies of typical radionuclides are measured for each virtual slice. Then, the peak count rate ratio is obtained, and the decay rate of the count rate for each radionuclide is obtained from the peak count rate ratio, and the direct line count rate is measured for each radionuclide, and the direct line count rate is calculated as the above decay rate. The radioactive amount of each radioactive nuclide is measured for each virtual slice, and the radioactive amount of each radioactive nuclide is integrated to obtain the radioactive amount of the solidified waste solidified drum waste. Alternatively or additionally, the gamma ray measurement with different collimator opening for each virtual slice is performed to obtain the ratio of peak count rates of direct rays at different collimator openings of representative radionuclides, that is, the collimator opening count rate ratio, which is obtained in advance. Obtain the effective density and radioactivity position for each virtual slice from the peak count rate ratio and the collimator opening count rate ratio based on the correlation, and obtain the attenuation rate of each radionuclide from the effective density and radioactivity position. , The direct line count rate measured for each radionuclide is corrected using the attenuation rate to measure the amount of each radionuclide for each virtual slice, and the amount of each radionuclide is integrated to calculate the solidified drum waste Radioactivity. When there is no radionuclide that emits gamma rays having different energies, the ratio of gross count rate to peak count rate may be used instead of the above peak count rate ratio.
【０００５】[0005]
【発明の実施の形態】以下添付の図面を参照して本発明
の実施形態を説明する。図１は、本発明方法を実施する
ための測定系の系統図である。測定対象のドラム缶詰放
射性廃棄物固化体Ａを載せる回転昇降台１の駆動制御系
は、計算機３に電気的に連絡し、一方ドラム缶詰放射性
廃棄物固化体Ａに対向して配置されるコリメータ５は開
口が調整可能であり、ガンマ線を測定できるゲルマニウ
ム検出器７がコリメータ５の開口に臨んで設けられてい
る。ゲルマニウム検出器７は、信号処理系９を介して計
算機３に連絡している。Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a system diagram of a measurement system for carrying out the method of the present invention. The drive control system of the rotary lift 1 on which the drum canned radioactive waste solidified body A is placed is electrically connected to the computer 3, while the collimator 5 arranged so as to face the drum canned radioactive waste solidified body A. The opening is adjustable, and a germanium detector 7 capable of measuring gamma rays is provided facing the opening of the collimator 5. The germanium detector 7 is in communication with the computer 3 via the signal processing system 9.
【０００６】測定に際し、ドラム缶詰放射性廃棄物Ａ
は、昇降回転台１のテーブル上面にその回転中心とドラ
ム缶の中心軸が整列するように載せられる。ガンマ線の
測定に際しては図２に示すようにドラム缶詰放射性廃棄
物Ａは鉛直軸方向即ち高さ方向に複数（５個）の仮想ス
ライスＡ1，Ａ2，Ａ3，Ａ4，Ａ5に分けられる。勿論こ
の仮想スライスの個数は、測定の精度や効率等を考慮し
て適宜選択できるものである。コリメータ５とゲルマニ
ウム検出器７は高さ方向には固定されていて、対応する
１個の仮想スライス（図２ではＡ2）の全域からのガン
マ線のみが計測されるようにコリメータ５の開度が選定
されている。他の仮想スライスＡ1，Ａ3，Ａ4，Ａ5のガ
ンマ線を計測するには、回転昇降台１を適宜駆動して仮
想スライスの厚さに見合ったピッチで高さ方向に回転テ
ーブル乃至ドラム缶詰放射性廃棄物Ａを動かし、測定対
象の仮想スライスがコリメータ５の開口対応位置に来る
ようにすればよい。このようなピッチ移動は当業者にと
って通常のことであるので具体的なやり方の説明は割愛
する。In measuring, radioactive waste A in a drum can
Is placed on the upper surface of the table of the lifting / lowering turntable 1 such that its rotation center and the central axis of the drum can are aligned. When measuring gamma rays, the drum can radioactive waste A is divided into a plurality of (five) virtual slices A 1 , A 2 , A 3 , A 4 , A 5 in the vertical axis direction, that is, in the height direction as shown in FIG. To be Of course, the number of virtual slices can be appropriately selected in consideration of measurement accuracy and efficiency. The collimator 5 and the germanium detector 7 are fixed in the height direction, and the opening of the collimator 5 is set so that only gamma rays from the entire area of one corresponding virtual slice (A 2 in FIG. 2 ) are measured. It has been selected. To measure the gamma rays of the other virtual slices A 1 , A 3 , A 4 , and A 5 , the rotary lift 1 is appropriately driven to rotate in the height direction at a pitch corresponding to the thickness of the virtual slice. The canned radioactive waste A may be moved so that the virtual slice to be measured comes to the position corresponding to the opening of the collimator 5. Since such pitch movement is common to those skilled in the art, a detailed description of the method is omitted.
【０００７】次に各仮想スライスにおけるコリメータ５
の開口幅と水平面における測定範囲との関係が図式的に
図３に示されている。図３において、一つの開度でガン
マ線を計測するときは夾角αで計測し、異なる開度でガ
ンマ線を計測するときは夾角αと広角βとで計測する。
そして以上のようにコリメータ５の開口を通ったガンマ
線の直接線（非散乱線）は、ゲルマニウム検出器７に入
って検出され、後述するように計測値が計算機３に送ら
れて適宜な処理を受ける。Next, the collimator 5 in each virtual slice
The relationship between the opening width of the and the measurement range in the horizontal plane is schematically shown in FIG. In FIG. 3, when the gamma ray is measured at one opening, the included angle α is measured, and when the gamma ray is measured at different openings, the included angle α and the wide angle β are measured.
The direct gamma-ray line (non-scattered line) that has passed through the opening of the collimator 5 as described above enters the germanium detector 7 and is detected, and the measured value is sent to the computer 3 for appropriate processing as described later. receive.
【０００８】以上のような測定系を用い、ドラム缶詰放
射性廃棄物Ａがコバルトの同位元素Ｃｏ−６０とセシウ
ムの同位元素Ｃｓ−１３７を内蔵する場合の本発明によ
る測定方法を説明する。Ｃｏ−６０は、１．３３MeＶと
１．１７MeＶのガンマ線を放出し、Ｃｓ−１３７は０．
６６２MeＶのガンマ線を放出する。このような背景か
ら、密度補正のための代表核種としてＣｏ−６０を選択
する。 基準状態（密度が零で放射能位置が仮想スライスの中
心）に定めたコリメータ開度（夾角α）でＣｏ−６０、
Ｃｓ−１３７が各１Ｂｑ存在したときのＣｏ−６０の
１．３３MeＶのピーク計数率Ｎ3＊,Ｃｓ−１３７の０．
６６２MeＶのピーク計数率Ｎc＊を設定する。 前述の定めたコリメータ開度（夾角α）に対し、Ｃｏ
−６０の１．１７MeＶピーク計数率Ｎ1と１．３３MeＶ
のピーク計数率Ｎ3の比Ｎ1／Ｎ3の関数で密度及び線源
位置を変化させて、Ｃｏ−６０とＣｓ−１３７に対する
規格化したピーク計数率の減衰率の存在範囲（図４及び
図５）を求める。 ピーク係数率比Ｎ1／Ｎ3に対し、ピーク計数率の減衰
率の存在領域幅が狭いので、図４及び図５から存在領域
幅の中央を取る操作により、図６に示すようなＣｏ−６
０のピーク計数率Ｎ3とＣｓ−１３７のピーク計数率Ｎc
の代表的減衰曲線をＮ1／Ｎ3の関数で各々設定する（Ｃ
ｏ−６０：ｆ3(Ｎ1／Ｎ3),Ｃｓ−１３７:fc(Ｎ1／
Ｎ3))。 各仮想スライスの測定されたピーク計数率（Ｃｏ−６
０：Ｎ1、Ｎ3、Ｃｓ−１３７：Ｎc）を基に各仮想スラ
イスの放射能を次の式で求める。 Ｃｏ−６０の放射能量＝Ｎ1／Ｎ3＊×１／ｆ3(Ｎ1／
Ｎ3) Ｃｓ−１３７の放射能量＝Ｎc／Ｎc＊×１／ｆc(Ｎ1／
Ｎ3)A measuring method according to the present invention in which the drum canned radioactive waste A contains the cobalt isotope Co-60 and the cesium isotope Cs-137 using the above measuring system will be described. Co-60 emits 1.33 MeV and 1.17 MeV gamma rays, and Cs-137 has a .0.
It emits 662 MeV gamma rays. From such a background, Co-60 is selected as a representative nuclide for density correction. Co-60 at the collimator opening (inclusion angle α) set in the standard state (the density is zero and the radioactivity position is the center of the virtual slice),
When Cs-137 was present at 1 Bq each, the peak count rate N 3 * of 1.33 MeV of Co-60, 0.
Set a peak count rate N c * of 662 MeV. For the collimator opening (inclusion angle α) defined above, Co
-60 1.17 MeV peak count rate N 1 and 1.33 MeV
The density and the radiation source position are changed as a function of the ratio N 1 / N 3 of the peak count rate N 3 to the normal range of the peak count rate attenuation rates for Co-60 and Cs-137 (FIG. 4 and Figure 5) is obtained. Since the existence region width of the attenuation factor of the peak count rate is narrower than the peak coefficient ratio ratio N 1 / N 3 , the operation of taking the center of the existence region width from FIG. 4 and FIG. 6
0 peak count rate N 3 and Cs-137 peak count rate N c
A typical decay curve of each of the above is set by a function of N 1 / N 3 (C
o-60: f 3 (N 1 / N 3 ), Cs-137: f c (N 1 /
N 3 )). The measured peak count rate of each virtual slice (Co-6
Based on 0: N 1 , N 3 , Cs-137: N c ), the radioactivity of each virtual slice is calculated by the following formula. Radioactivity of Co-60 = N 1 / N 3 * × 1 / f 3 (N 1 /
N 3) the amount of radioactivity Cs-137 = N c / N c * × 1 / f c (N 1 /
N 3 )
【０００９】次にコリメータ５の開口幅を変える場合の
測定方法を同様なドラム缶詰放射性廃棄物Ａの放射能量
を測定する場合を説明する。 前述の実施形態と同様に基準状態でのＣｏ−６０の
１．３３MeＶのピーク計数率Ｎ3＊,Ｃｓ−１３７の０．
６６２MeＶのピーク計数率Ｎc＊を設定する。 前述と同様に定めたコリメータ開度（夾角α）に対
し、ピーク計数率比Ｎ1／Ｎ3と密度・放射能位置を変化
させて、図４及び図５に示すようなピーク計数率の減衰
率を放射性核種別に求める。 異なるコリメータ開度（広角β）での代表核種のピー
ク計数率Ｎ3aと所定コリメータ開度（夾角α）でのピー
ク計数率Ｎ3の比（ コリメータ開度計数率比Ｎ3a／
Ｎ3）を用いて図７に示すピーク計数率比Ｎ1／Ｎ3と密
度ρ（g/cc）と放射能位置γ（仮想スライスの中心から
径方向の距離cm）の相関図を作成する。 コリメータ開度（夾角α）での測定ピーク計数率
Ｎ1，Ｎ3，Ｎcとコリメータ開度（広角β）での測定ピ
ーク計数率Ｎ3aからピーク計数率比Ｎ1／Ｎ3、コリメー
タ開度計数率比Ｎ3a／Ｎ3を求め、これから実効的な密
度ρと放射能位置γを求める。 Ｃｏ−６０、Ｃｓ−１３７に対し求めた実効的な密度
ρとピーク計数率比Ｎ1／Ｎ3を用いて図４及び図５に示
すような放射性核種別の計数率の減衰曲線よりＣｏ−６
０とＣｓ−１３７のピーク計数率の減衰率を求める。 前述のピーク計数率とその減衰率より各仮想スライス
に含まれるＣｏ−６０とＣｓ−１３７の放射能量を算出
する。Next, a measuring method in the case of changing the opening width of the collimator 5 will be described in the case of measuring the radioactivity of a similar drum-canned radioactive waste A. As in the previous embodiment, the peak count rate N 3 *, Cs-137 of Co-60 of 1.33 MeV in the standard state of 0.
Set a peak count rate N c * of 662 MeV. Attenuation of the peak count rate as shown in FIGS. 4 and 5 by changing the peak count rate ratio N 1 / N 3 and the density / radioactivity position with respect to the collimator opening (inclusion angle α) determined in the same manner as described above. Calculate the rate by radionuclide type. Different collimator opening ratio of the peak count rate N 3 at (a wide angle beta) in the peak count rate N 3a and a predetermined collimator opening of representative species of the (included angle alpha) (collimator opening count rate ratio N 3a /
N 3 ) is used to create a correlation diagram of peak count rate ratio N 1 / N 3 , density ρ (g / cc), and radioactivity position γ (radial distance cm from the center of the virtual slice) shown in FIG. . From the measured peak count rates N 1 , N 3 , N c at the collimator opening (angle α) and the measured peak count rate N 3a at the collimator opening (wide angle β) to the peak count rate ratio N 1 / N 3 , the collimator open. The frequency count rate ratio N 3a / N 3 is calculated, and from this, the effective density ρ and the radioactivity position γ are calculated. Using the effective densities ρ and peak count rate ratios N 1 / N 3 obtained for Co-60 and Cs-137, Co-from the decay curves of count rates of radionuclides as shown in FIGS. 6
The decay rate of the peak count rate of 0 and Cs-137 is calculated. The radioactivity amounts of Co-60 and Cs-137 contained in each virtual slice are calculated from the above-mentioned peak count rate and its attenuation rate.
【００１０】[0010]
【発明の効果】以上説明したように、本発明によれば、
各仮想スライスについて代表放射性核種のピーク計数率
比からその減衰率を求め、その減衰率を用いて測定計数
率を補正して各放射性核種別の放射能量を求めるので、
密度や放射能位置の偏在による誤差を無くしてドラム缶
詰放射性廃棄物固化体の正確な放射能量を測定すること
ができる。As described above, according to the present invention,
Since the attenuation rate is calculated from the peak count rate ratio of the representative radionuclide for each virtual slice, and the measured count rate is corrected using that attenuation rate to determine the radioactivity of each radionuclide,
It is possible to eliminate the error due to uneven distribution of density and radioactive position, and to measure the exact radioactivity of the solidified waste solidified drum can.
【図１】本発明の実施形態で用いられる測定系の系統図
である。FIG. 1 is a system diagram of a measurement system used in an embodiment of the present invention.
【図２】前記実施形態での測定の状態を示す概念的説明
図である。FIG. 2 is a conceptual explanatory diagram showing a measurement state in the embodiment.
【図３】前記実施形態での測定の状態を示す概念的説明
図である。FIG. 3 is a conceptual explanatory diagram showing a measurement state in the embodiment.
【図４】前記実施形態での測定の途中で作成される特性
図である。FIG. 4 is a characteristic diagram created during the measurement in the embodiment.
【図５】前記実施形態での測定の途中で作成される特性
図である。FIG. 5 is a characteristic diagram created during the measurement in the embodiment.
【図６】前記実施形態での測定の途中で作成される別の
特性図である。FIG. 6 is another characteristic diagram created during the measurement in the embodiment.
【図７】前記実施形態での測定の途中で作成される更に
別の特性図である。FIG. 7 is another characteristic diagram created during the measurement in the embodiment.
１ 回転昇降台 ３ 計算機 ５ コリメータ ７ ゲルマニウム検出器 Ａ ドラム缶詰放射性廃棄物固化体 Ａ1〜Ａ5 仮想スライス α コリメータ開度（夾角） β コリメータ開度（広角）1 rotary elevator 3 computer 5 collimator 7 germanium detector A drum canned radioactive waste solidified body A 1 to A 5 virtual slice α collimator opening (inclusion angle) β collimator opening (wide angle)
Claims (3)
缶詰放射性廃棄物固化体の放出するガンマ線を、鉛直軸
方向に沿って仮想的に分割されてできた複数の仮想スラ
イス毎にコリメータ付きガンマ線スペクトル検出器で検
出し、前記仮想スライス毎の放射能量を積算して前記ド
ラム缶詰放射性廃棄物固化体の全放射能量とする放射能
量測定方法において、 前記仮想スライス毎に代表的放射性核種のエネルギの異
なる２つの直接線ピーク計数率を測定してピーク計数率
比を求め、 同ピーク計数率比から各放射性核種毎の計数率の減衰率
を求め、 各放射性核種について直接線計数率を測定し、その直接
線計数率を前記減衰率を用いて補正して前記仮想スライ
ス毎の各放射性核種量を測定することを特徴とする放射
性廃棄物固化体の放射能量測定方法。1. A gamma ray spectrum with a collimator for each of a plurality of virtual slices formed by virtually dividing the gamma rays emitted from the solidified waste canned radioactive waste placed on a rotary lifting table along the vertical axis direction. Detected by a detector, in the method of measuring the amount of radioactivity for each virtual slice by integrating the amount of radioactivity for each virtual slice to obtain the total amount of radioactivity of the solidified waste solidified radioactive waste in the drum, the energy of the representative radionuclide is different for each virtual slice. The peak count rate ratio is calculated by measuring two direct line peak count rates, the decay rate of the count rate for each radionuclide is calculated from the peak count rate ratio, and the direct line count rate is measured for each radionuclide. Radioactivity measurement of solidified radioactive waste, characterized by measuring the radionuclide amount for each virtual slice by correcting the direct line count rate using the attenuation rate Method.
缶詰放射性廃棄物固化体の放出するガンマ線を、鉛直軸
方向に沿って仮想的に分割されてできた複数の仮想スラ
イス毎にコリメータ付きガンマ線スペクトル検出器で検
出し、前記仮想スライス毎の放射能量を積算して前記ド
ラム缶詰放射性廃棄物固化体の全放射能量とする放射能
量測定方法において、 前記仮想スライス毎に代表的放射性核種のエネルギの異
なる２つの直接線ピーク計数率を測定してピーク計数率
比を求め、 前記仮想スライス毎にコリメータ開度の異なる測定を行
って代表放射性核種のコリメータ開度計数率比を求め、 予め求められた相関関係を基に前記ピーク計数率比と前
記コリメータ開度計数率比から前記仮想スライス毎に実
効的密度と放射能位置を求め、 前記実効的密度と放射能位置から各放射性核種の減衰率
を求め、 各放射性核種について測定した直接線計数率をその減衰
率を用いて補正して前記仮想スライス毎の各放射性核種
量を測定することを特徴とする放射性廃棄物固化体の放
射能量測定方法。2. A gamma ray spectrum with a collimator for each of a plurality of virtual slices formed by virtually dividing the gamma rays emitted from the solidified waste material of a drum canned radioactive waste placed on a rotary elevation table along a vertical axis. Detected by a detector, in the method of measuring the amount of radioactivity for each virtual slice by integrating the amount of radioactivity for each virtual slice to obtain the total amount of radioactivity of the solidified waste solidified radioactive waste in the drum, the energy of the representative radionuclide is different for each virtual slice. The two direct line peak count rates are measured to obtain the peak count rate ratio, and the collimator opening count rate ratio of the representative radionuclide is determined by measuring the collimator opening different for each of the virtual slices. Based on the relationship between the peak count rate ratio and the collimator opening count rate ratio to determine the effective density and radioactivity position for each virtual slice, the actual The decay rate of each radionuclide is determined from the dynamic density and the radioactivity position, and the direct line count rate measured for each radionuclide is corrected using that decay rate to measure each radionuclide amount for each virtual slice. A method for measuring the amount of radioactivity of a solidified radioactive waste.
射性核種が存在しないときは、前記ピーク計数率比に代
えてグロスの計数率とピーク計数率の比を用いることを
特徴とする請求項１又は請求項２記載の放射性廃棄物固
化体の放射能量測定方法。3. The ratio of gross count rate to peak count rate is used in place of the peak count rate ratio when there is no radionuclide that emits gamma rays of different energies. Item 2. A method for measuring the radioactivity of a solidified radioactive waste material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6477896A JP3241262B2 (en) | 1996-03-21 | 1996-03-21 | Radioactivity measurement method for solidified radioactive waste |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6477896A JP3241262B2 (en) | 1996-03-21 | 1996-03-21 | Radioactivity measurement method for solidified radioactive waste |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09257937A true JPH09257937A (en) | 1997-10-03 |
| JP3241262B2 JP3241262B2 (en) | 2001-12-25 |
Family
ID=13268018
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6477896A Expired - Lifetime JP3241262B2 (en) | 1996-03-21 | 1996-03-21 | Radioactivity measurement method for solidified radioactive waste |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3241262B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL1010392C2 (en) * | 1998-10-26 | 2000-04-27 | Stichting Energie | Device for inspecting barrels. |
| CN109283568A (en) * | 2018-11-20 | 2019-01-29 | 阳江核电有限公司 | A kind of radioactive water filter gives up filter core measuring system and method |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101260486B1 (en) | 2012-02-23 | 2013-05-06 | 한국수력원자력 주식회사 | Apparatus for calculating radioactive amount in radioactive waste drum |
-
1996
- 1996-03-21 JP JP6477896A patent/JP3241262B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL1010392C2 (en) * | 1998-10-26 | 2000-04-27 | Stichting Energie | Device for inspecting barrels. |
| WO2000025152A1 (en) * | 1998-10-26 | 2000-05-04 | Stichting Energieonderzoek Centrum Nederland | Device for inspecting radioactive drums |
| CN109283568A (en) * | 2018-11-20 | 2019-01-29 | 阳江核电有限公司 | A kind of radioactive water filter gives up filter core measuring system and method |
| CN109283568B (en) * | 2018-11-20 | 2020-07-17 | 阳江核电有限公司 | System and method for measuring waste filter element of radioactive water filter |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3241262B2 (en) | 2001-12-25 |
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