JPH0565036B2 - - Google Patents
Info
- Publication number
- JPH0565036B2 JPH0565036B2 JP8358986A JP8358986A JPH0565036B2 JP H0565036 B2 JPH0565036 B2 JP H0565036B2 JP 8358986 A JP8358986 A JP 8358986A JP 8358986 A JP8358986 A JP 8358986A JP H0565036 B2 JPH0565036 B2 JP H0565036B2
- Authority
- JP
- Japan
- Prior art keywords
- silver
- radioactive iodine
- silver nitrate
- iodine
- impregnated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 229910052709 silver Inorganic materials 0.000 claims description 82
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 76
- 239000004332 silver Substances 0.000 claims description 76
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 claims description 70
- 229910052740 iodine Inorganic materials 0.000 claims description 70
- 239000011630 iodine Substances 0.000 claims description 70
- 239000003463 adsorbent Substances 0.000 claims description 61
- 238000001179 sorption measurement Methods 0.000 claims description 56
- 230000002285 radioactive effect Effects 0.000 claims description 47
- 229910021612 Silver iodide Inorganic materials 0.000 claims description 42
- 239000007789 gas Substances 0.000 claims description 35
- 238000010438 heat treatment Methods 0.000 claims description 29
- 238000000034 method Methods 0.000 claims description 14
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 claims description 13
- 150000001875 compounds Chemical class 0.000 claims description 10
- 238000012545 processing Methods 0.000 claims description 9
- JKFYKCYQEWQPTM-UHFFFAOYSA-N 2-azaniumyl-2-(4-fluorophenyl)acetate Chemical compound OC(=O)C(N)C1=CC=C(F)C=C1 JKFYKCYQEWQPTM-UHFFFAOYSA-N 0.000 claims description 8
- 229940045105 silver iodide Drugs 0.000 claims description 8
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims 3
- 238000007599 discharging Methods 0.000 claims 3
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 description 44
- 229910001961 silver nitrate Inorganic materials 0.000 description 22
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 18
- 101710134784 Agnoprotein Proteins 0.000 description 11
- 238000006243 chemical reaction Methods 0.000 description 11
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 238000000354 decomposition reaction Methods 0.000 description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- 230000008859 change Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 239000000741 silica gel Substances 0.000 description 6
- 229910002027 silica gel Inorganic materials 0.000 description 6
- 239000000126 substance Substances 0.000 description 5
- 238000002441 X-ray diffraction Methods 0.000 description 4
- 229910021536 Zeolite Inorganic materials 0.000 description 4
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 4
- 238000002386 leaching Methods 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000012958 reprocessing Methods 0.000 description 4
- 238000003860 storage Methods 0.000 description 4
- 239000010457 zeolite Substances 0.000 description 4
- 238000004140 cleaning Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000004817 gas chromatography Methods 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 239000003513 alkali Substances 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 239000004568 cement Substances 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000007711 solidification Methods 0.000 description 2
- 230000008023 solidification Effects 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- VAYROLOSUUAGTR-UHFFFAOYSA-N [Ag].[I] Chemical class [Ag].[I] VAYROLOSUUAGTR-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000005273 aeration Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000010956 nickel silver Substances 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000002901 radioactive waste Substances 0.000 description 1
- 239000012495 reaction gas Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 229940100890 silver compound Drugs 0.000 description 1
- 150000003379 silver compounds Chemical class 0.000 description 1
- 210000001685 thyroid gland Anatomy 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
- 238000013022 venting Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Description
〔発明の利用分野〕
本発明は放射性ヨウ素の方法及び処理装置に係
り、特に硝酸銀添着吸着材に吸着した長半減期放
射性ヨウ素の安定な処理方法および装置に関す
る。
〔発明の背景〕
原子力施設では周辺住民の放射能被曝を防止す
るため、周辺環境に放出される放射能量を低減す
るための種々の対策が講じられている。このうち
放射性ヨウ素に対しては、これが人体の甲状腺に
選択的に吸収され放射能被曝を増大させるため、
特に厳格な放出放射能量の低減対策が施されてい
る。特に、再処理プラントでは、原子力発電所か
ら放出される131I（半減期８日）に比べ、長半減
期（1.7×107年）の129Iが放出されるため、特に
厳格な放出放射能量の低減対策がとられている。
放射性ヨウ素の直接的放出の系統となるオフガ
ス系では、アルカリ洗浄塔、銀添着吸着材充填塔
の２段処理が行われている。アルカリ洗浄塔は、
大量の放射性ヨウ素を除去できるが、オフガス中
のヨウ素のうち有機ヨウ素（主成分CH3I）が除
去できないので、高い除去性能が期待できず、ま
た、廃液の発生量が多いという問題がある。一
方、銀添着吸着材充填塔は高価であるが、I2、
CH3I共に高効率で除去できるメリツトがある。
現状は、これらの２つの方式を組合せて、周辺環
境への放射性ヨウ素の放出放射能量を、環境に影
響しないように、低減している。
近年、再処理オフガス系の放射性ヨウ素の除去
システムの見直しが行なわれ、アルカリ洗浄塔に
よる前段処理をせずに、銀添着吸着材充填塔単独
で放射性ヨウ素を除去するシステムが有望視され
ている。
一般に知られている銀添着吸着材としては、銀
ゼオライト、銀シリカゲルおよび特開昭56−
108532号記載の銀アルミナの３つがある。これら
の銀添着吸着材は、２つのタイプに分けることが
できる。すなわち、銀をイオン交換によつて添着
した吸着材と、多孔性の物質に硝酸銀として添着
した吸着材である。前者に属するものは、銀ゼオ
ライトであり、後者に属するものは、銀アルミナ
と銀シリカゲルである。この２つのタイプの吸着
材のヨウ素の吸着容量を測定した結果、銀ゼオラ
イトでは添着した銀の60％程度しかヨウ素の吸着
に利用されないが、銀アルミナ、銀シリカゲルで
は添着銀の90％以上がヨウ素との反応に利用され
る。この点から、銀シリカゲル、銀アルミナなど
の硝酸銀添着吸着材は、添着された銀が有効に利
用され、高価な銀の使用量を低減できるため、コ
スト面で特に優れていると云える。
上記の硝酸銀添着吸着材充填塔単独では放射性
ヨウ素を除去する方式では、放射性ヨウ素が化学
的、物理的に安定な銀の化合物として固定される
といわれており、放射性廃棄物の取扱が容易であ
るといわれてきた。しかしながら、放射性ヨウ素
と硝酸銀添着吸着材との反応については、西独の
WAKなどでの研究例があるものの、未だ明確に
されていない。
そこで、本発明者らは放射性ヨウ素と硝酸銀添
着吸着材での硝酸銀との反応を明確にし、その問
題点を明らかにして、硝酸銀添着吸着材充填塔単
独による放射性ヨウ素除去システムの信頼性を高
める方策を見出すことが必要であると考えた。
〔発明の目的〕
本発明の目的は、放射性ヨウ素と硝酸銀添着吸
着材の硝酸銀との反応およびそれに伴う問題点並
びにその解決手段を明らかにし、以て放射性ヨウ
素を安定に処理する方法及び装置を提供すること
にある。
〔発明の概要〕
本発明は、本発明者らの実験により、放射性ヨ
ウ素と硝酸銀添着吸着材の硝酸銀との反応生成物
中にヨウ化銀（AgI）以外の銀とヨウ素との化合
物が含まれていることを見い出し、さらに、この
銀とヨウ素との化合物をすべて安定なAgIに変え
る方法を見い出した結果によるものである。
本発明の放射性ヨウ素の処理方法は、放射性ヨ
ウ素を硝酸銀添着吸着材に吸着させた後、該吸着
材中のヨウ化銀以外の銀とヨウ素との化合物を安
定なヨウ化銀に変えることに特徴がある。
放射性ヨウ素を吸着した硝酸銀添着吸着材中の
ヨウ化銀以外の銀とヨウ素との化合物をヨウ化銀
に変えるためには、該放射性ヨウ素を吸着した硝
酸銀添着吸着材を400〜800℃に加熱するか、又
は、該放射性ヨウ素を吸着した硝酸銀添着吸着材
に、NO／NO2が0.2以上となる還元性ガスを通気
する。
本発明は以下の実験結果に基づきなされたもの
である。
再処理プラントオフガス中には、放射性ヨウ素
が約100ppm含まれており、その化学形態は全量
の約90％が分子状ヨウ素（I2）、残り約10％が有
機ヨウ素（主成分CH3I）である。そこで発明者
らは、I2とCH3Iについて、銀アルミナとの反応
性を検討した。この検討では、銀アルミナを充填
した吸着塔に、I2またはCH3Iを含む模擬ガスを
通気し、吸着塔から出てくる反応ガスを紫外線吸
光光度計およびガスクロによつて同定および定量
した。さらに、ヨウ素吸着後の硝酸銀添着吸着材
（銀アルミナ）中の硝酸銀とヨウ素との反応生成
物をＸ線回折によつて同定した。
以上の結果を、第２図および第１表に示す。第
２図はI2またはCH3I吸着後の硝酸銀添着吸着材
のＸ線回折パターンである。この結果から、
CH3Iを吸着した場合、AgIのみが生成している
ことがわかる。一方、I2を吸着した場合には、
AgIとAgIO3とが生成していることがわかる。
AgIO3についてはASTMの標準回折パターンが
ないため、和光純薬製のAgIO3のＸ線回折パター
ンと比較した。なお、図中のAl2O3の回折ピーク
は担体であるアルミナによるものである。これら
の銀とヨウ素との化合物の生成および反応式を決
定するため、ガスクロによる吸着塔出口ガスの組
成を測定した。ガスクロおよびＸ線回折の結果、
第１表に示す反応式を得た。
[Field of Application of the Invention] The present invention relates to a method and apparatus for treating radioactive iodine, and more particularly to a method and apparatus for stably treating long-half-life radioactive iodine adsorbed on a silver nitrate-impregnated adsorbent. [Background of the Invention] In order to prevent surrounding residents from being exposed to radiation, various measures are taken to reduce the amount of radioactivity released into the surrounding environment at nuclear facilities. Of these, radioactive iodine is selectively absorbed by the human thyroid gland, increasing radiation exposure.
Particularly strict measures have been taken to reduce the amount of released radioactivity. In particular, reprocessing plants release 129 I, which has a longer half-life (1.7 x 10 7 years) than the 131 I released from nuclear power plants (half-life 8 days), so the amount of radioactivity released is particularly strict. Measures are being taken to reduce this. In the off-gas system, which is the system for direct release of radioactive iodine, a two-stage treatment including an alkali cleaning tower and a silver-impregnated adsorbent-packed tower is performed. The alkaline cleaning tower is
Although it can remove a large amount of radioactive iodine, it cannot remove organic iodine (main component CH 3 I) from the iodine in the off-gas, so high removal performance cannot be expected and there is also the problem of generating a large amount of waste liquid. On the other hand, silver-impregnated adsorbent packed towers are expensive, but
It has the advantage of being able to remove both CH 3 I with high efficiency.
Currently, these two methods are combined to reduce the amount of radioactive iodine released into the surrounding environment so as not to affect the environment. In recent years, systems for removing radioactive iodine from reprocessing off-gas systems have been reviewed, and a system that removes radioactive iodine using a silver-impregnated adsorbent-packed tower alone, without pretreatment using an alkali cleaning tower, is seen as promising. Generally known silver-impregnated adsorbents include silver zeolite, silver silica gel, and
There are three types of silver alumina described in No. 108532. These silver-loaded adsorbents can be divided into two types. That is, there are two types of adsorbents: one in which silver is impregnated by ion exchange, and the other in which silver is impregnated as silver nitrate on a porous substance. Those belonging to the former category are silver zeolite, and those belonging to the latter category are silver alumina and silver silica gel. As a result of measuring the iodine adsorption capacity of these two types of adsorbents, it was found that in silver zeolite, only about 60% of the impregnated silver is used to adsorb iodine, but in silver alumina and silver silica gel, more than 90% of the impregnated silver is iodine. It is used in the reaction with From this point of view, adsorbents impregnated with silver nitrate such as silver silica gel and silver alumina can be said to be particularly advantageous in terms of cost, since the impregnated silver is effectively utilized and the amount of expensive silver used can be reduced. In the method of removing radioactive iodine using the above-mentioned silver nitrate-impregnated adsorbent packed tower alone, radioactive iodine is said to be fixed as a chemically and physically stable silver compound, making it easy to handle radioactive waste. It has been said that However, regarding the reaction between radioactive iodine and adsorbent impregnated with silver nitrate, the West German
Although there are research examples such as WAK, it is still not clear. Therefore, the present inventors clarified the reaction between radioactive iodine and silver nitrate in a silver nitrate-impregnated adsorbent, clarified the problems, and took measures to improve the reliability of a radioactive iodine removal system using a silver nitrate-impregnated adsorbent packed column alone. I thought it was necessary to find out. [Object of the Invention] The object of the present invention is to clarify the reaction between radioactive iodine and silver nitrate in a silver nitrate-impregnated adsorbent, the problems associated therewith, and means for solving the same, and thereby provide a method and apparatus for stably processing radioactive iodine. It's about doing. [Summary of the Invention] The present invention is based on experiments conducted by the present inventors, in which a compound of silver and iodine other than silver iodide (AgI) is contained in the reaction product of radioactive iodine and silver nitrate of a silver nitrate-impregnated adsorbent. This is the result of discovering that AgI is a stable compound of silver and iodine, and also finding a way to convert all of this compound of silver and iodine into stable AgI. The method for treating radioactive iodine of the present invention is characterized in that after radioactive iodine is adsorbed onto a silver nitrate-impregnated adsorbent, compounds of silver and iodine other than silver iodide in the adsorbent are converted into stable silver iodide. There is. In order to convert compounds of silver and iodine other than silver iodide in the silver nitrate-impregnated adsorbent that has adsorbed radioactive iodine into silver iodide, the silver nitrate-impregnated adsorbent that has adsorbed the radioactive iodine is heated to 400 to 800°C. Alternatively, a reducing gas such that NO/NO 2 is 0.2 or more is passed through the silver nitrate-impregnated adsorbent that has adsorbed radioactive iodine. The present invention was made based on the following experimental results. The reprocessing plant off-gas contains approximately 100 ppm of radioactive iodine, and its chemical form is approximately 90% molecular iodine (I 2 ) and the remaining 10% organic iodine (main component CH 3 I). It is. Therefore, the inventors investigated the reactivity of I 2 and CH 3 I with silver alumina. In this study, a simulated gas containing I 2 or CH 3 I was passed through an adsorption tower filled with silver alumina, and the reaction gas coming out of the adsorption tower was identified and quantified using an ultraviolet absorption photometer and gas chromatography. Furthermore, a reaction product between silver nitrate and iodine in the silver nitrate-impregnated adsorbent (silver alumina) after iodine adsorption was identified by X-ray diffraction. The above results are shown in FIG. 2 and Table 1. FIG. 2 is an X-ray diffraction pattern of the adsorbent impregnated with silver nitrate after I 2 or CH 3 I adsorption. from this result,
It can be seen that when CH 3 I is adsorbed, only AgI is produced. On the other hand, when I 2 is adsorbed,
It can be seen that AgI and AgIO 3 are generated.
Since there is no ASTM standard diffraction pattern for AgIO 3 , it was compared with the X-ray diffraction pattern of AgIO 3 manufactured by Wako Pure Chemical Industries. Note that the diffraction peak of Al 2 O 3 in the figure is due to alumina, which is a carrier. In order to determine the formation and reaction formula of these compounds of silver and iodine, the composition of the gas at the outlet of the adsorption tower was measured by gas chromatography. Gas chromatography and X-ray diffraction results,
The reaction formula shown in Table 1 was obtained.
本発明の好適な実施例を図面を用いて以下に詳
細に述べる。
実施例 １
第３図に加熱によるAgIO3の分解を実施する一
実施例の基本フローを示す。本実施例は、通気ガ
スを加熱するためのヒータ１６、硝酸銀添着吸着
材を充填した吸着塔１，２、吸着塔を加熱するた
めのヒータ４，５、バルブ６〜９，１７，１８か
ら構成される。放射性ヨウ素を含む処理ガスは、
ヒータ１６で約150℃に加熱されたのち、バルブ
６を介して吸着塔１に導入される。吸着塔１を出
たガスはバルブ８を介して後段の処理系統に導か
れる。この時バルブ６，８は開、バルブ７，９，
１７，１８は閉である。吸着塔１中の硝酸銀添着
吸着材が放射性ヨウ素を飽和吸着して、吸着塔１
出口から放射性ヨウ素が流出する直前に切り換え
操作を行なう。切り換え操作は次の様にして行な
う。まず、バルブ７，９を開として処理ガスが吸
着塔２に流れるようにする。次に、バルブ６，８
を閉とする。このようにして切り換えた後、バル
ブ１８，６を開として、バルブ１８を介して空気
または窒素供給源（図示せず）からこれらのガス
を吸着塔１に通気する。次いでヒータ４によつて
吸着塔１を加熱する。この時に吸着塔１内の硝酸
銀添着吸着材に変化が生ずる。この変化をI2を吸
着した銀アルミナ吸着材を例にとり説明する。第
４図は、I2を飽和吸着した銀アルミナ吸着材の重
量変化を、ヨウ素の放出量を加熱温度の関数とし
て示した図である。この図からわかるように、約
400℃でAgIO3が、AgIとO2とに分解するが、こ
の際、ヨウ素は全く放出されない。ヨウ素の放出
は、約800℃でヨウ化銀の気化によつて生ずる。
したがつて加熱温度を400〜800℃の範囲にするこ
とによつて、ヨウ素の放出がなく、AgIO3をAgI
に変化させることができる。この事実から、ヒー
タ４による吸着塔１の加熱温度は400〜800℃とす
ることが必要である。AgIO3の分解によつて生ず
るO2は、バルブ１８を介して導入される空気ま
たは窒素ガスと共に吸着塔１から流出し、処理ガ
スとともにバルブ６，７を介して吸着塔２に導入
される。パルブ１８を介して導入される空気また
は窒素ガスの流量は、処理ガスの1/10程度であ
り、吸着塔２の処理能力を超えない。この後、吸
着塔１を放冷し、吸着塔１内の使用済硝酸銀添着
吸着材を一時貯蔵タンク（図示せず）に移し、新
しい硝酸銀添着吸着材を吸着塔１に充填する。吸
着塔２中の硝酸銀添着吸着材が放射性ヨウ素を飽
和吸着して、吸着塔２から放射性ヨウ素が流出す
る直前に再度切り換え操作を行ない、吸着塔１に
処理ガスを通気する。吸着塔２中の硝酸銀添着吸
着材を加熱処理して、吸着塔１と同様、AgIO3を
AgIに変化させる。このようにして、吸着塔１と
吸着塔２を交互に切り換え使用する。
以上の実施例により、硝酸銀添着吸着材上の
AgIO3は化学的に安定なAgIに変化する。その効
果を、耐水性の点から具体的に述べる。第５図
は、I2を吸着しただけの銀アルミナと、I2を吸着
した後600℃の加熱処理をした銀アルミナの吸着
ヨウ素の浸出比の時間変化を示した図である。こ
こで浸出比は、銀アルミナの2000倍容の水に銀ア
ルミナを浸漬し、初めに吸着していたヨウ素量に
対する溶出ヨウ素量の比として求めた。図からわ
かるように、600℃の加熱処理をした銀アルミナ
は、加熱処理をしない銀アルミナよりも1000倍浸
出しにくい。
また、ヨウ素吸着後の銀添着吸着材をセメント
で固化して得た固化体の水浸漬試験を実施した。
試験に使用した固化体は直径50mm高さ50mmであ
る。ヨウ素吸着後そのまま固化したものでは５日
間の水浸漬後、浸出比が８×10-4であつたが、本
発明による加熱処理を実施した後固化したもので
は、検出限界10-6以下であつた。
したがつて、上記実施例により、硝酸銀添着吸
着材上のAgIO3は化学的に安定なAgIに変化する
ことがわかる。これによつて、耐水性が高くなる
だけでなく、含酸素化合物が消滅するため有機物
との接触による異常発熱などの恐れがなくなる。
したがつて、本実施例の適用により、硝酸銀添着
吸着材による高効率ヨウ素除去と、一時保管の安
定性向上、さらにはセメント固化など水硬性物質
による固化が可能となる。
実施例 ２
第１図に加熱によつてAgIO3を分解する最も好
適な実施例の基本フローを示す。本実施例は、通
気ガスを加熱するためのヒータ１６、硝酸銀添着
吸着材を充填した吸着塔１，２、使用済の硝酸銀
添着吸着材を加熱処理するための加熱ポツト３、
加熱ポツト３を加熱するためのヒータ４、吸着材
を吸引輸送するための吸引ブロワ１５、バルブ６
〜１４から構成される。実施例１と同様に、放射
性ヨウ素を含む処理ガスは、ヒータ１６で約150
℃に加熱されたのち、吸着塔１に通気される。こ
のときバルブ６，８は開、バルブ７，９〜１４は
閉である。吸着塔１中の硝酸銀添着吸着材が放射
性ヨウ素を飽和吸着して、吸着塔１出口から放射
性ヨウ素が流出する直前に、バルブ７，９を開、
バルブ６，８を閉として、吸着塔１から吸着塔２
に切り換える。この後、バルブ１１，１３を開と
して、ブロワ１５を作動させる。これによつて吸
着塔１内の使用済硝酸銀添着吸着材は、加熱ポツ
ト３に空気とともに移送される。この移送方式
は、米国CVI社で既に開発されており、実用化さ
れている。移送された硝酸銀添着吸着材は、ヒー
タ４によつて加熱ポツト３内で400〜800℃の範囲
となるように加熱され、AgIO3がAgIに変化す
る。このときバルブ１３は閉で、バルブ１４は開
となり、バルブ１４に接続される空気または窒素
供給源（図示せず）より、空気または窒素が供給
される。供給される空気または窒素は、処理ガス
量に比べきわめて少ない。このようにして処理さ
れた硝酸銀添着吸着材は、加熱ポツトから、一時
貯蔵タンク（図示せず）に移される。また吸着塔
１には新らしい吸着材が充填される。吸着塔２中
の硝酸銀添着吸着材が、放射性ヨウ素を飽和吸着
して、吸着塔２から放射性ヨウ素が流出する直前
に再度切り換えを行う。吸着塔２中の硝酸銀添着
吸着材は、吸着塔１の場合と同様に処理され、空
となつた吸着塔２内には新しい硝酸銀添着吸着材
を充填する。このようにして、吸着塔１と吸着塔
２を交互に切り換え使用する。
上記、実施例では、実施例１と同様に、使用済
硝酸銀添着吸着材の安定性が向上するだけでな
く、実施例１と比較して高温の加熱器が１基と少
なくてすむメリツトがある。
上記実施例１、２では、AgI以外の銀とヨウ素
との化合物としてAgIO3の例をとりあげたが、硝
酸銀添着吸着材とヨウ素との反応において生成し
うるAgI以外の銀とヨウ素との化合物としては
AgI3がある。これは、化学的に不安定であり、
容易にヨウ素（I2）を放出してAgIに変化する傾
向がある。従つて使用済の硝酸銀添着吸着材中に
AgI3が存在していると、雰囲気中への放射性ヨ
ウ素の放出につながり危険である。実施例１、２
では、AgI3の分解も可能である。この分解反応
は次のように生ずる。
AgI3→AgI＋I2
この反応によつて生じたI2は、使用済の硝酸銀
添着吸着材中のヨウ素と反応していない銀
（AgNO3またはAg）と反応して吸着されるか、
または、処理ガスと共にオフガス処理系統に導び
かれ、吸着される。
実施例 ３
上記１、２の実施例は加熱によるAgIO3の分解
であるが、CO、NOなどの還元性ガスを通気す
ることによつてAgIO3を分解する実施を次に述べ
る。特にNOは、再処理プラントの排ガスの処理
系にNOの処理装置があることから有利である。
ここではNOの場合を例にとつて、より具体的に
述べる。第６図はNO／NO2の比とAgIの生成比
との関係を示した図である。ここで言うNO／
NO2の比は、AgIO3の還元と密接な関連がある。
なぜならAgIO3は次式によつてAgIに変化し、
NO2が過剰となると一度生成したAgIがAgIO3と
なるためである。
AgIO3＋3NOAgI＋3NO2
第６図からわかるように、NO／NO2が0.2以
上、すなわちNOの量が多くなるとAgIが100％生
成する。したがつてNO／NO2比が0.2以上のガス
を用いればよいことがわかる。２のとき酸素を含
まない不活性ガスがNO、NO2以外にあつてもよ
い。これを具体的に実施するためには、第３図で
はバルブ１７，１８を介して還元性ガスを導入す
ればよく、また第１図ではバルブ１４を介して還
元性ガスを導入すればよい。またこの反応は、０
℃においても生ずるため、加熱は不要となる。し
たがつて、本方法によれば、高温の加熱装置がな
くても、AgIO3の分解が可能となる。また、還元
性ガスなどのガスを通気する方法でも、AgI3を
AgIに変えることができる。これは、通気によつ
て、AgI3の分解生成物であるI2（気体）が取り除
かれ、AgI3分解が促進されるためである。
上記実施例１、２、３では、ヨウ素と反応せず
に残留した硝酸銀（AgNO3）も分解できる。
AgNO3の溶解度は62wt％と、AgIに比べ107倍、
AgIO3に比べ104倍大きいため、使用済の硝酸銀
添着吸着材に残留AgNO3が存在すると、水と接
触したとき残留するAgNO3の溶出が生じ、
AgNO3と一緒に存在するAgIやAgIO3が機械的
にはく離し、水に溶出する。このように、残留す
るAgNO3によつて放射性ヨウ素の溶出量が増大
する。このように耐水性を低下させる残留
AgNO3は、実施例１、２においては、次のよう
な反応によつてAgまたはAg2Oに変化する。
（440℃以上）
AgNO3→Ag＋NO＋O2
2AgNO3→Ag2O＋2NO＋3/2O2
また、実施例３においては、次のような反応に
よつてAgまたはAg2Oが生成する。
2AgNO3→NO→Ag2O＋3NO2
Ag2O＋NO→Ag＋NO2
これらAg、Ag2Oの溶解度はそれぞれ2.8×
10-8g／c.c.、２×10-5g／c.c.であり、それぞれ
AgNO3の1/107、1/104である。このように、残
留するAgNO3の分解も実施例１、２、３のいず
れでも同様に達成され、使用済の硝酸銀添着吸着
材の耐水性、化学的安定性の向上が可能である。
なお、上記諸実施例では、硝酸銀添着吸着材と
して銀アルミナの実験結果のみを述べたが、銀シ
リカゲルでも同様の効果を奏することを実験的に
確認している。これに対し、銀ゼオライトを用い
ることは、銀アルミナ、銀シリカゲルを用いた場
合とは全く異なり、吸着したヨウ素の一部が300
℃程度で放出されることが発明者らの実験により
明らかとなつている。
〔発明の効果〕
本発明によれば、放射性ヨウ素を吸着した硝酸
銀添着吸着材上のAgI以外のヨウ着−銀化合物
（AgIO3、AgI3）を化学的に安定なAgIに変える
ので、硝酸銀添着吸着材によるヨウ素除去から一
時保管をへて固化に到る一連の放射性ヨウ素の処
理処分の信頼性を向上させることができる。
Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Example 1 FIG. 3 shows the basic flow of an example of decomposing AgIO 3 by heating. This embodiment is composed of a heater 16 for heating ventilation gas, adsorption towers 1 and 2 filled with adsorbent impregnated with silver nitrate, heaters 4 and 5 for heating the adsorption tower, and valves 6 to 9, 17, and 18. be done. Processing gas containing radioactive iodine is
After being heated to about 150° C. by a heater 16, it is introduced into the adsorption tower 1 via a valve 6. The gas exiting the adsorption tower 1 is led to a downstream treatment system via a valve 8. At this time, valves 6 and 8 are open, valves 7 and 9,
17 and 18 are closed. The silver nitrate-impregnated adsorbent in the adsorption tower 1 saturates and adsorbs radioactive iodine, and the adsorption tower 1
The switching operation is performed just before radioactive iodine flows out from the outlet. The switching operation is performed as follows. First, the valves 7 and 9 are opened to allow the process gas to flow into the adsorption tower 2. Next, valves 6 and 8
Let be closed. After switching in this manner, valves 18, 6 are opened and these gases are vented into adsorption column 1 via valve 18 from an air or nitrogen source (not shown). Next, the adsorption tower 1 is heated by the heater 4. At this time, a change occurs in the adsorbent impregnated with silver nitrate in the adsorption tower 1. This change will be explained using a silver alumina adsorbent that adsorbed I 2 as an example. FIG. 4 is a diagram showing the weight change of a silver alumina adsorbent that has saturated I 2 adsorption as a function of the amount of iodine released as a function of heating temperature. As you can see from this figure, about
AgIO 3 decomposes into AgI and O 2 at 400°C, but no iodine is released at this time. Release of iodine occurs by vaporization of silver iodide at about 800°C.
Therefore, by setting the heating temperature in the range of 400 to 800℃, there is no release of iodine, and AgIO 3 can be converted to AgI.
can be changed to From this fact, it is necessary that the heating temperature of the adsorption tower 1 by the heater 4 be 400 to 800°C. O 2 produced by the decomposition of AgIO 3 flows out of the adsorption tower 1 together with air or nitrogen gas introduced through the valve 18 and is introduced into the adsorption tower 2 through the valves 6 and 7 together with the process gas. The flow rate of air or nitrogen gas introduced through the valve 18 is about 1/10 of the processing gas, and does not exceed the processing capacity of the adsorption tower 2. Thereafter, the adsorption tower 1 is allowed to cool, the spent adsorbent impregnated with silver nitrate in the adsorption tower 1 is transferred to a temporary storage tank (not shown), and the adsorption tower 1 is filled with new adsorbent impregnated with silver nitrate. Immediately before the silver nitrate-impregnated adsorbent in the adsorption tower 2 saturates and adsorbs radioactive iodine and the radioactive iodine flows out from the adsorption tower 2, the switching operation is performed again to vent the treated gas into the adsorption tower 1. The silver nitrate-impregnated adsorbent in adsorption tower 2 is heat-treated to release AgIO 3 in the same way as in adsorption tower 1.
Change to AgI. In this way, adsorption tower 1 and adsorption tower 2 are alternately used. According to the above examples, the
AgIO 3 changes to chemically stable AgI. The effect will be specifically described in terms of water resistance. FIG. 5 is a diagram showing changes over time in the leaching ratio of adsorbed iodine for silver alumina that has only adsorbed I 2 and for silver alumina that has been heat-treated at 600° C. after adsorbing I 2 . Here, the leaching ratio was determined by immersing silver alumina in water with a volume 2000 times that of silver alumina, and calculating the ratio of the amount of eluted iodine to the amount of iodine initially adsorbed. As can be seen from the figure, silver alumina heat-treated at 600°C is 1000 times more difficult to leach than silver alumina that is not heat-treated. In addition, a water immersion test was conducted on the solidified material obtained by solidifying the silver-impregnated adsorbent with cement after adsorbing iodine.
The solidified body used in the test had a diameter of 50 mm and a height of 50 mm. The leaching ratio of the product solidified after iodine adsorption was 8 x 10 -4 after 5 days of water immersion, but the leaching ratio was below the detection limit of 10 -6 in the case of the product solidified after heat treatment according to the present invention. Ta. Therefore, the above example shows that AgIO 3 on the adsorbent impregnated with silver nitrate changes to chemically stable AgI. This not only increases water resistance, but also eliminates the risk of abnormal heat generation due to contact with organic matter because oxygen-containing compounds disappear.
Therefore, by applying this example, it becomes possible to remove iodine with high efficiency using the adsorbent impregnated with silver nitrate, improve the stability of temporary storage, and further solidify with a hydraulic substance such as cement solidification. Example 2 FIG. 1 shows the basic flow of the most preferred example of decomposing AgIO 3 by heating. This embodiment includes a heater 16 for heating vent gas, adsorption towers 1 and 2 filled with silver nitrate-impregnated adsorbent, a heating pot 3 for heat-treating the used silver nitrate-impregnated adsorbent,
A heater 4 for heating the heating pot 3, a suction blower 15 for sucking and transporting the adsorbent, and a valve 6
It consists of ~14. As in Example 1, the processing gas containing radioactive iodine was heated to about 150 ml by the heater 16.
After being heated to .degree. C., it is vented into the adsorption tower 1. At this time, valves 6 and 8 are open, and valves 7 and 9 to 14 are closed. Immediately before the silver nitrate-impregnated adsorbent in the adsorption tower 1 saturates and adsorbs radioactive iodine and the radioactive iodine flows out from the outlet of the adsorption tower 1, valves 7 and 9 are opened;
With valves 6 and 8 closed, adsorption tower 1 to adsorption tower 2
Switch to . After that, the valves 11 and 13 are opened and the blower 15 is operated. As a result, the spent adsorbent impregnated with silver nitrate in the adsorption tower 1 is transferred to the heating pot 3 together with air. This transfer method has already been developed and put into practical use by CVI Corporation in the United States. The transferred silver nitrate-impregnated adsorbent is heated in the heating pot 3 by the heater 4 to a temperature in the range of 400 to 800°C, and AgIO 3 is changed to AgI. At this time, the valve 13 is closed, the valve 14 is open, and air or nitrogen is supplied from an air or nitrogen supply source (not shown) connected to the valve 14. The amount of air or nitrogen supplied is extremely small compared to the amount of gas to be processed. The silver nitrate impregnated adsorbent thus treated is transferred from the heating pot to a temporary storage tank (not shown). Also, the adsorption tower 1 is filled with a new adsorbent. The silver nitrate-impregnated adsorbent in the adsorption tower 2 saturates and adsorbs radioactive iodine, and the switching is performed again just before the radioactive iodine flows out from the adsorption tower 2. The silver nitrate-impregnated adsorbent in the adsorption tower 2 is treated in the same manner as in the adsorption tower 1, and the empty adsorption tower 2 is filled with new silver nitrate-impregnated adsorbent. In this way, adsorption tower 1 and adsorption tower 2 are alternately used. In the above example, as in example 1, not only is the stability of the spent silver nitrate-impregnated adsorbent improved, but compared to example 1, there is an advantage that the number of high-temperature heaters is reduced to one. . In Examples 1 and 2 above, AgIO 3 was taken as an example of a compound of silver and iodine other than AgI, but as a compound of silver and iodine other than AgI that can be produced in the reaction between a silver nitrate impregnated adsorbent and iodine. teeth
There is AgI 3 . It is chemically unstable and
It tends to easily release iodine (I 2 ) and convert into AgI. Therefore, in the used adsorbent impregnated with silver nitrate,
The presence of AgI 3 is dangerous as it can lead to the release of radioactive iodine into the atmosphere. Examples 1 and 2
In this case, the decomposition of AgI 3 is also possible. This decomposition reaction occurs as follows. AgI 3 → AgI + I 2 The I 2 generated by this reaction reacts with the silver (AgNO 3 or Ag) that has not reacted with iodine in the used silver nitrate-impregnated adsorbent and is adsorbed, or
Alternatively, it is guided to an off-gas treatment system together with the processing gas and is adsorbed. Example 3 Although the above Examples 1 and 2 involve the decomposition of AgIO 3 by heating, the following describes an implementation in which AgIO 3 is decomposed by passing a reducing gas such as CO or NO. In particular, NO is advantageous because there is a NO treatment device in the exhaust gas treatment system of the reprocessing plant.
Here, we will discuss the case in more detail by taking the case of NO as an example. FIG. 6 is a diagram showing the relationship between the NO/NO 2 ratio and the AgI production ratio. Say NO/
The ratio of NO2 is closely related to the reduction of AgIO3 .
Because AgIO 3 changes to AgI by the following formula,
This is because when NO 2 becomes excessive, AgI once generated becomes AgIO 3 . AgIO 3 +3NOAgI+3NO 2 As can be seen from Figure 6, when NO/NO 2 is 0.2 or more, that is, when the amount of NO increases, 100% of AgI is generated. Therefore, it can be seen that it is sufficient to use a gas with a NO/NO 2 ratio of 0.2 or more. In case 2, an inert gas that does not contain oxygen may be present other than NO or NO 2 . In order to specifically implement this, the reducing gas may be introduced through the valves 17 and 18 in FIG. 3, and the reducing gas may be introduced through the valve 14 in FIG. 1. Also, this reaction is 0
It also occurs at ℃, so heating is not necessary. Therefore, according to this method, AgIO 3 can be decomposed without a high-temperature heating device. In addition, AgI 3 can also be produced by venting gas such as reducing gas.
Can be converted to AgI. This is because aeration removes I 2 (gas), which is a decomposition product of AgI 3 , and promotes AgI 3 decomposition. In Examples 1, 2, and 3, silver nitrate (AgNO 3 ) remaining without reacting with iodine can also be decomposed.
The solubility of AgNO 3 is 62wt%, which is 10 7 times that of AgI.
Since it is 104 times larger than AgIO 3 , if residual AgNO 3 is present in the used silver nitrate-impregnated adsorbent, the residual AgNO 3 will elute when it comes into contact with water.
AgI and AgIO 3 present together with AgNO 3 are mechanically separated and eluted into water. In this way, the remaining AgNO 3 increases the amount of radioactive iodine eluted. Residues that reduce water resistance in this way
In Examples 1 and 2, AgNO 3 is changed to Ag or Ag 2 O by the following reaction. (440° C. or higher) AgNO 3 →Ag+NO+O 2 2AgNO 3 →Ag 2 O+2NO+3/2O 2 In Example 3, Ag or Ag 2 O is produced by the following reaction. 2AgNO 3 →NO→Ag 2 O＋3NO 2 Ag 2 O＋NO→Ag＋NO 2The solubility of each of these Ag and Ag 2 O is 2.8×
10 -8 g/cc, 2×10 -5 g/cc, respectively.
It is 1/10 7 and 1/10 4 of AgNO 3 . In this way, the decomposition of the remaining AgNO 3 was similarly achieved in all of Examples 1, 2, and 3, and it is possible to improve the water resistance and chemical stability of the used adsorbent impregnated with silver nitrate. In the above examples, only the experimental results using silver alumina as the adsorbent impregnated with silver nitrate have been described, but it has been experimentally confirmed that silver silica gel has the same effect. On the other hand, using silver zeolite is completely different from using silver alumina or silver silica gel, in that some of the adsorbed iodine
Experiments conducted by the inventors have revealed that it is released at temperatures of around 100°C. [Effects of the Invention] According to the present invention, the iodine-silver compounds (AgIO 3 , AgI 3 ) other than AgI on the silver nitrate-impregnated adsorbent adsorbed with radioactive iodine are changed into chemically stable AgI, so that the silver nitrate-impregnated adsorbent It is possible to improve the reliability of the series of treatment and disposal of radioactive iodine, from iodine removal using an adsorbent to temporary storage and solidification.
第１図は加熱によつてAgIO3を分解する本発明
の最も好適な実施例のフローを示した図、第２図
はI2およびCH3I吸着後の硝酸銀添着吸着材のＸ
線回折パターンを示した図、第３図は加熱によつ
てAgIO3を分解する本発明の好適な他の実施例の
フローを示した図、第４図は加熱温度とI2吸着後
の硝酸銀添着吸着材の重量変化及びヨウ素の放出
量との関係を示した図、第５図は加熱処理の有無
による水に対するヨウ素の浸出量の時間変化を示
した図、第６図はNO／NO2の比とAgIの生成比
との関係を示した図である。
符号の説明 １，２…吸着塔、３…加熱ポツ
ト、４，５，１６…ヒータ、６〜１４，１７，１
８…バルブ、１５…吸引ブロワ。
Figure 1 shows the flow of the most preferred embodiment of the present invention in which AgIO 3 is decomposed by heating, and Figure 2 shows the X
Figure 3 shows the flow of another preferred embodiment of the present invention in which AgIO 3 is decomposed by heating; Figure 4 shows the heating temperature and silver nitrate after I 2 adsorption. Figure 5 is a diagram showing the relationship between the weight change of the impregnated adsorbent and the amount of iodine released. Figure 5 is a diagram showing the time change in the amount of iodine leached from water with and without heat treatment. Figure 6 is NO/NO 2. FIG. 2 is a diagram showing the relationship between the ratio of AgI and the production ratio of AgI. Explanation of symbols 1, 2... Adsorption tower, 3... Heating pot, 4, 5, 16... Heater, 6-14, 17, 1
8... Valve, 15... Suction blower.
Claims (1)
る工程、該工程を経た硝酸銀添着吸着材中のヨウ
化銀以外の銀とヨウ素との化合物をヨウ化銀に変
える工程よりなることを特徴とする放射性ヨウ素
の処理方法。 ２ 上記後者の工程は、放射性ヨウ素を吸着した
硝酸銀添着吸着材を400〜800℃に加熱することに
よつて行う特許請求の範囲第１項記載の放射性ヨ
ウ素の処理方法。 ３ 上記後者の工程は放射性ヨウ素を吸着した硝
酸銀添着吸着材に還元性ガスを通気することによ
つて行う特許請求の範囲第１項記載の放射性ヨウ
素の処理方法。 ４ 還元性ガスは、NO／NO2が0.2以上の窒素酸
化物ガスである特許請求の範囲第３項に記載の放
射性ヨウ素の処理方法。 ５ 硝酸銀添着吸着材の充填・排出の可能な並列
の複数の吸着塔、放射性ヨウ素含有ガスを該吸着
塔に選択的に切換えて流す手段、該吸着塔内部を
夫々400〜800℃に選択的に加熱する手段、加熱時
の分解ガスを夫々の吸着塔から排出する手段を備
えたことを特徴とする放射性ヨウ素の処理装置。 ６ 硝酸銀添着吸着材の充填可能な並列の複数の
吸着塔、放射性ヨウ素含有ガスを該吸着塔に選択
的に切換えて流す手段、共通容器、該共通容器内
に吸着塔内の硝酸銀添着吸着材を選択的に移送す
る手段、該共通容器内部を400〜800℃に加熱する
手段、加熱時の分解ガスを該共通容器から排出す
る手段を備えたことを特徴とする放射性ヨウ素の
処理装置。[Scope of Claims] 1. Consisting of a step of adsorbing radioactive iodine to a silver nitrate-impregnated adsorbent, and a step of converting a compound of silver and iodine other than silver iodide in the silver nitrate-impregnated adsorbent after this step into silver iodide. A method for processing radioactive iodine. 2. The method for treating radioactive iodine according to claim 1, wherein the latter step is carried out by heating a silver nitrate-impregnated adsorbent adsorbed with radioactive iodine to 400 to 800°C. 3. The method for treating radioactive iodine according to claim 1, wherein the latter step is carried out by passing a reducing gas through a silver nitrate-impregnated adsorbent that has adsorbed radioactive iodine. 4. The method for treating radioactive iodine according to claim 3, wherein the reducing gas is a nitrogen oxide gas with a NO/NO 2 ratio of 0.2 or more. 5. A plurality of parallel adsorption towers capable of filling and discharging silver nitrate-impregnated adsorbent, means for selectively switching and flowing radioactive iodine-containing gas to the adsorption towers, and selectively heating the inside of each of the adsorption towers to 400 to 800°C. 1. A radioactive iodine processing apparatus characterized by comprising heating means and means for discharging decomposed gas from each adsorption tower during heating. 6. A plurality of parallel adsorption towers that can be filled with silver nitrate-impregnated adsorbent, means for selectively switching and flowing the radioactive iodine-containing gas to the adsorption towers, a common container, and the silver nitrate-impregnated adsorbent in the adsorption towers in the common container. 1. An apparatus for processing radioactive iodine, comprising means for selectively transferring, means for heating the inside of the common container to 400 to 800°C, and means for discharging decomposed gas from the common container during heating.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8358986A JPS62239098A (en) | 1986-04-11 | 1986-04-11 | Method and device for processing radioactive iodine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8358986A JPS62239098A (en) | 1986-04-11 | 1986-04-11 | Method and device for processing radioactive iodine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62239098A JPS62239098A (en) | 1987-10-19 |
| JPH0565036B2 true JPH0565036B2 (en) | 1993-09-16 |
Family
ID=13806673
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8358986A Granted JPS62239098A (en) | 1986-04-11 | 1986-04-11 | Method and device for processing radioactive iodine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62239098A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2540401B2 (en) * | 1991-11-05 | 1996-10-02 | 動力炉・核燃料開発事業団 | Method for precipitating and separating radioactive iodine compounds |
-
1986
- 1986-04-11 JP JP8358986A patent/JPS62239098A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62239098A (en) | 1987-10-19 |
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|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |