環境放射能除染学会誌

ሗ ࿌Vol.1, No.2, pp.139-142, 2013ᅵተࢆ㝖ཤࡏࡎ⌧ሙ࡛ሷ⁐ᾮࢆᅵተ୰࡟ᚠ⎔ࡉࡏࡿࡇ࡜࡟ࡼࡿ㝖ᰁࡢྍ⬟ᛶ㙊⏣ ៞ᮁ*ᐑᇛᩍ⫱኱Ꮫ ᩍ⫱Ꮫ㒊ᐑᇛ┴௝ྎᕷ㟷ⴥ༊ⲨᕳᏐ㟷ⴥ 149 ␒ᆅ 㻌㻌

On Site Removal of Radioactive Contamination by Circulating Salt Solution in
Contaminated SoilYoshiro KAMATA*

Miyagi University of Education
149 Aramaki-aza-Aoba, Aoba-ku, Sendai, Miyagi 980-0845 Japan
Summary
A method to collect radioactive material on site effectively without removing surface soil was studied. Cesium whichbound to the soil electrostatically was solubilized by circulating a salt solution in the soil. Half molar ammonium acetate wasused for circulation. On the other hand, cesium which bound to the soil strongly was removed effectively by collecting fineparticles of the soil. The fine particles adsorb much cesium, because the surface area of such a fine particles is relatively large.
A salt solution was poured into the soil through a large number of pipes. The solution which leached out was collected with adifferent pipe at the surface of the soil. The collected solution was supplied again to the injection pipes. Two or three times ofone-hour circulation was performed. The fine particles were collected using a filter paper. The fine particles and remaining
soil were dried at 140㽅C for 20 hours. Radioactivity was measured about the filtrate, the fine particles and the residual soil.
When water was used for circulation the dissolved radioactive material was around 3%. In this case around 16 % ofradioactive material was included in the fine particles. When 0.5M ammonium acetate solution including the alginic acid(200 mg/L) was used for circulation liquid, 12 % of radioactive material dissolved. In this case the radioactive material
collected in the circulation liquid and the fine particles was 42 %. On the other hand, the dry mass of the fine particles was
18 % of all dry soil. This shows that much radioactive material adheres to relatively small amount of the fine particles.

rofyteicoSehtefvoitlcaanoriutdonaeR©Jfmononrioiv
tnaiEdeehtniRemnoitanimatConKey Words: Soil, On Site Removal, Salt Solution, Circulation, Fine Particle1㸬⥴ㄽ཰  ࠊ࠶ࡿ࠸ࡣࢭࢩ࣒࢘ࡢẼ໬ ᗘ௨ୖࡢ㧗 ࡛ࡢฎ⌮  ࡞࡝ཎⓎ஦ᨾ࡛㣕ᩓࡋ㝆ୗࡋࡓࢭࢩ࣒࢘ࡣᅵተ࡟྾╔ࡉࢀࠊᅵࡀヨࡳࡽࢀ࡚࠸ࡿࠋࡋ࠿ࡋࠊ㎰ᆅࡢ㝖ᰁࢆ⪃៖ࡍࡿ࡜ࡇࢀࡽᆅࡢẚ㍑ⓗ⾲㠃࡟␃ࡲࡿᛶ㉁ࡀ࠶ࡿ ࠋࡑࡇ࡛ࠊከࡃࡢሙྜࠊࡢฎ⌮ࡣࠊࡑࡢᅵተࡢ㎰⪔⏝ࡢᇶ┙࡛࠶ࡿᰤ㣴ᡂศ࡞࡝ࡶኻ⾲ᅵࡢ㝖ཤࡀ᭷ຠ࡞㝖ᰁࡢ᪉ἲ࡜ࡋ࡚ᐇ᪋ࡉࢀ࡚࠸ࡿࠋࡋ࠿ࢃࡏ࡚ࡋࡲ࠺ࡇ࡜࡟࡞ࡿ࡜ᛮࢃࢀࠊࡲࡓࠊࡇࢀࡽࡢ᪉ἲࡣࠊࡋࠊࡇࡢ᪉ἲࢆ඲࡚ࡢᅵተࠊ≉࡟㎰ᆅ࡟㐺⏝ࡍࡿ࡜ࡍࢀࡤࠊᅵተࢆ๐ࡾྲྀࡾࠊฎ⌮᪋タ࡟㐠ᦙࡋࠊከࡃࡢ࢚ࢿࣝࢠ࣮ࢆ⏝ࡑࡢ㔞ࡣ⭾኱࡜࡞ࡾࠊ㝖ཤࡋࡓᅵተࡢಖ⟶ࡸฎศࡣᅔ㞴࡞ㄢ࠸࡚ฎ⌮ࡋࠊ෌ࡧ⌧ᆅ࡟㐠ࢇ࡛ᡠࡍࡇ࡜ࢆᚲせ࡜ࡋ┦ᙜࡢࢥࢫ㢟࡜࡞ࡿ࡜⪃࠼ࡽࢀࡿࠋࢺ ⌧ᅾࠊᅵተ࠿ࡽࡢᨺᑕᛶࢭࢩ࣒࢘ࡢ㝖ཤἲࡀᵝࠎᥦ᱌ࡉࡍࡇ࡜࡬ࡢ᢬ᢠឤࡶ኱ࡁ࠸ࡢ࡛ࡣ࡞࠸࠿࡜ᛮࢃࢀࡿࠋ௨ୖࡢࢀ࡚࠸ࡿࠋᅵተ࡬ࡢࢭࢩ࣒࢘ࡢ྾╔ࡣᙉᅛ࡛࠶ࡾࠊࡇࢀࢆᘬ⌧≧ࢆ⪃៖ࡋࠊ⾲ᅵࢆ㝖ཤࡍࡿࡇ࡜࡞ࡃ⌧ᆅ࡛ᨺᑕᛶࢭࢩ࢘ࡁࡣࡀࡍ࡟ࡣࠊ㓟࡟ࡼࡿฎ⌮ࡀ࠿࠿ࡿࡶࡢ࡜ᛮࢃࢀࡿࠋࡲࡓࠊ୍᪦㝖ཤࡋࡓᅵተࢆ෌ࡧᡠࠊᅵተ⢏Ꮚࡢᚤ⣽໬࡟ࡼࡿᅇ࣒ࢆຠ⋡ⓗ࡟ᅇ཰ࡍࡿ᪉ἲ࡟ࡘ࠸᳨࡚ウࡋࡓࠋ*Corresponding author: Tel: 022-214-3476, Fax: 022-268-4327, E-mail: y-kama@staff.miyakyo-u.ac.jp― 139 ―

2㸬ᮦᩱཬࡧ᪉ἲ㸦1㸧ᮦᩱ ởᰁᅵተࡣ⚟ᓥ┴ᅜぢ⏫ࡢ㐨㊰ࢃࡁ┒ࡾᅵ㒊ศ࡛᥇ྲྀࡋࡓࠋ᥇ྲྀᆅⅬࡣᒣഃᩳ㠃ࡢ㐨㊰ࢆᣳࢇ࡛཯ᑐഃ࡛ࠊᩳ㠃࠿ࡽࡢὶධࡼࡾࡣ㝆㞵࡞࡝࡟ࡼࡿ┤᥋ởᰁࡀ୺య࡛ࡣ࡞࠸࠿࡜ᛮࢃࢀࡓࠋࡲࡓࠊⴠⴥ࡞࡝ࡢ⵳✚ࡶぢࡽࢀࡎࠊ◁≧ࡢࡶࡢ࡛࠶ࡗࡓࠋ஝⇱ࡋࡓᅵተࡢ⢏ᗘࡣ┠㛤ࡁ 500 μm ࡜ 106 μm ࡢࡩࡿ࠸ࢆ

ࢭࢵࢺࡋࡓ࣑ࢽࡩࡿ࠸᣺࡜࠺ᶵ㸦MVS-1ࠊAS ONE㸧࡛ᐃࡋࡓ⤖ᯝࠊ500 μm ௨ୖࡀ 63.7±5.2%㸦ᖹᆒsᶆ‽೫ᕪ㸧ࠊ106㹼500 μm ࡀ 32.3±4.7%ࠊ106 μm ௨ୗࡀ 4.0±0.5%࡛࠶ࡗ

ࡓࠋࡇࡢᅵተࡢᨺᑕ⥺ࡢ⡆᫆ ᐃ್ࡣࣂࢵࢡࢢࣛ࢘ࣥࢻࢆᕪ

ࡋᘬ࠸࡚ 0.448±0.040 μSv/h/kg㸦ᖹᆒsᶆ‽೫ᕪ㸧࡛ࠊ ᐃჾ࣓࣮࣮࢝ࡢ⡆᫆᥮⟬ࢢࣛࣇ࡟ࡼࢀࡤࠊ⣙ 6,000㹼20,000

Bq/kg ⛬ᗘࡢᨺᑕᛶ≀㉁ࢆྵࡴࡶࡢ࡜ᛮࢃࢀࡓࠋ౑⏝ࡋࡓ⸆

Fig. 2 Photograph of circulating systemရ㢮ࡣ≉⣭ࢆ⏝࠸ࡓࠋ

㸦2㸧㝖ᰁ⿦⨨ࡇࡢ⿦⨨ࡣࠊ⏕ࡅⰼ࡟౑࠺๢ᒣࡢࡼ࠺࡟ࢭࢵࢺࡋࡓከᩘࡢ

ࣇ࢕ࣝࢱ࣮⿦⨨ࡣࠊ࠶ࡲࡾ⣽࠿࠸࡜ࡍࡄ࡟ワࡲࡗ࡚ࡋࡲ࠺

ࣃ࢖ࣉࢆ㏻ࡋ࡚ᾮయࢆᅵተ୰࡟ὀධࡋࠊࡑࡢᾮయࡀᅵተࡢ⾲ࡢ࡛ࠊ࣏࢚ࣜࢳࣞࣥࢿࢵࢺࢆ୸ࡵ࡚࢞ࣛࢫ〇ࢧ࢖ࢡࣟࣥ࡟ワ㠃࡟ᾐࡳฟࡋ࡚ࡃࡿ࡜ࡁ࡟ࠊᅵተࡢᚤ⢏Ꮚᡂศࢆᕳࡁ㎸ࢇ࡛

ࡵ㎸ࢇࡔࡶࡢࢆ⏝࠸ࡓࠋࡇࢀ࡛࠶ࡿ⛬ᗘࡢ኱ࡁࡉࡢ⢏Ꮚࡣᅇࡃࡿࡇ࡜ࢆᮇᚅࡋࡓ᪉ἲ࡛࠶ࡿࠋࡲࡓࠊὀධࡍࡿᾮయࡣࠊ࠸཰࡛ࡁࡿࡀࠊ࡟ࡈࡾ⛬ᗘࡢᚤ⢏Ꮚࡣᅇ཰࡛ࡁ࡞࠿ࡗࡓࠋࡋ࠿ࡲࡔྍ⁐ᛶࡢ≧ែ࡟࠶ࡿࢭࢩ࣒࢘ࢆ⁐࠿ࡋฟࡍࡇ࡜ࢆᮇᚅࡋࡋࠊ⢏ᚄࡀᑠࡉ࠸࡯࡝ከࡃࡢࢭࢩ࣒࢘ࢆ྾╔ࡋ࡚࠸ࡿྍ⬟ᛶሷ⁐ᾮࢆ⏝࠸ࡓࠋሷ⁐ᾮࡢヲ⣽ࡣ 2 (3) 㐠㌿᮲௳࡟♧ࡋࡓࠋࡀ࠶ࡿࡢ࡛ࠊ࡟ࡈࡾࡣᚠ⎔⤊஢ᚋࢁ⣬࡟ࡼࡿࢁ㐣࡛ᅇ཰ࡋࡓࠋ

rofyteicoSehte
fvoitlcaanoriutdonaeR©Jfmononrioiv
tnaiEdeehtniRemnoitanimatCon㑅ࢇࡔࠋࡉࡽ࡟ὀධ᫬࡟ࠊࣃ࢖ࣉࢆࡺࡍࡗ࡚ࠊᚤ⢏Ꮚࡀ⯙࠸㸦3㸧㐠㌿᮲௳
ヨᩱᅵተ 200 g ࢆ࢞ࣛࢫ〇ᐜჾ㸦ෆᑍ 7013050 mm㸧

ୖࡀࡾࡸࡍ࠸ࡼ࠺࡟ࡋࡓࠋ࡟ධࢀࠊ㝖ᰁ⿦⨨ࡢࣃ࢖ࣉࢆᤄධࡋࡓࠋሷ⁐ᾮ࡜ࡋ࡚ࡣ㓑ࡲࡓࠊሷ⁐ᾮࡣṧᏑࡋ࡚ࡶ࠿ࡲࢃ࡞࠸⫧ᩱ࡟࡞ࡾ࠺ࡿࡶࡢࢆ

ࣔࢹࣝᐇ㦂࡟⏝࠸ࡓ⿦⨨ࡢᴫせࢆ Fig. 1 ࡟ࠊᐇ㝿ࡢእほࢆ㓟࢔ࣥࣔࢽ࣒࢘ࢆ⏝࠸ࡓࠋࡇࢀࡣࠊᚋࡢ ᐃ᫬࡟ຍ⇕஝⇱

Fig. 2 ࡟♧ࡍࠋእᚄ 10 mmࠊ㛗ࡉ 100 mm ࡢࢳࢱࣥࣃ࢖ࣉࢆ࡟ࡼࡗ࡚㝖ཤ࡛ࡁࡿࡓࡵ࡛࠶ࡿࠋࡑࡢ௚ࠊ◲㓟࢔ࣥࣔࢽ࣒࢘

ࢫ࣏ࣥࢪ࡟➼㛫㝸࡟ᕪࡋ㎸ࡳࠊࢫ࣏ࣥࢪࡢ཯ᑐഃ࠿ࡽࢳ࣮ࣗ

ࡸ◪㓟࢔ࣥࣔࢽ࣒࢘ࡶヨࡳࡓࡀࠊ⤖ᯝ࡟ࡣ኱ࡁ࡞㐪࠸ࡣ࡞࠿ࡗ

ࣈ࣏ࣥࣉ㸦EYELA ROLLER PUMP RP-1000ࠊᮾி⌮໬ჾࡓࠋᚠ⎔㏿ᗘࡣ 600 ml/minࠊᚠ⎔᫬㛫ࡣ 1 ᫬㛫ࢆ୰ᚰ࡜ࡋ࡚Ე㸧ࢆ⏝࠸࡚ሷ⁐ᾮࢆ㏦ࡾ㎸ࢇࡔࠋࡇࢀࢆᅵተࡢୖ࡟஌ࡏࠊ࠸ࡿࡀࠊ▷࠸࡟㉺ࡋࡓࡇ࡜ࡣ࡞࠸ࡢ࡛ 5 ศࡶヨࡳࡓࠋᚠ⎔ᅇ⁐ᾮࢆ࣏ࣥࣉ࡛㏦ࡾࡇࡴ࡜ࠊࣃ࢖ࣉࡣᚎࠎ࡟ᅵተ୰࡟₯ࡾᩘ࡜ࡣࠊᚠ⎔ࢆ࠸ࡗࡓࢇṆࡵ࡚ሷ⁐ᾮ࡜ᚤ⢊ࢆᅇ཰ࡋࠊ᪂ࡓ㎸ࢇ࡛࠸ࡗࡓࠋ
୰ᚰࡢⓑ࠸ࣃ࢖ࣉࡣᾮయࡢᅇ཰⏝ࡢࡶࡢ࡛ࠊ࡞⁐ᾮ࡛ᚠ⎔ࡋࡓᅇᩘࢆ♧ࡍࠋᚠ⎔ᾮ࡜ࡋ࡚ࡣࠊỈ㐨Ỉࠊ࢔ᅇ཰ࡋࡓᾮయࡣࣇ࢕ࣝࢱ࣮⿦⨨ࢆ⤒࡚෌ࡧࢳࢱࣥࣃ࢖ࣉ࡟ࣝࢠࣥ㓟ࢼࢺ࣒ࣜ࢘⁐ᾮ㸦200 mg/L㸧ࠊ0.5 M 㓑㓟࢔ࣥࣔࢽ࢘

㏦ࡾ㎸ࡲࢀࡿࠋ࣒Ỉ⁐ᾮ࡟࢔ࣝࢠࣥ㓟ࢼࢺ࣒ࣜ࢘㸦200 mg/L㸧ࢆ⁐ゎࡋࡓࡶࡢࢆ⏝࠸ࡓࠋ࢔ࣝࢠࣥ㓟ࡢจ㞟࡟ࡣࠊሷ໬࢝ࣝࢩ࣒࢘ࢆ 400
mg/L ᢞධࡋࡓࠋᚠ⎔ᾮ࡟ࡘ࠸࡚ࡣࡑࡢࡲࡲᨺᑕ⬟ࢆ ᐃࡋࡓࠋᚤ⢊ᅵተࡣᅇ཰࡟⏝࠸ࡓࣇ࢕ࣝࢱ࣮ࡸࢁ⣬࡜୍⥴࡟

140ºCࠊ20 ᫬㛫஝⇱ࡋ࡚ࠊࡲࡓṧࡗࡓᅵተࡶྠᵝ࡟஝⇱ࡋ࡚ᨺᑕ⬟ࢆ ᐃࡋࡓࠋ

㸦4㸧ᨺᑕ⥺ᙉᗘࡢ ᐃᨺᑕ⥺ᙉᗘࡢ ᐃ࡟ࡣࠊ⡆᫆ ᐃჾ㸦HORIBA PA-100ࠊ

ᇼሙ〇సᡤ㸧࡜ ᐃ࢟ࢵࢺ㸦HORIBA PA-Kࠊᇼሙ〇సᡤ㸧ࢆ⏝࠸ࡓࠋࡇࡢ ᐃ࢟ࢵࢺࢆ⏝࠸ࡿ࡜ࠊ ᐃჾ࡜ヨᩱࡢ㊥㞳ࢆ୍ᐃ࡟ಖࡘࡇ࡜ࡀ࡛ࡁࡿࡢ࡛ࠊ෌⌧ᛶࡢⰋ࠸ ᐃࡀ࡛ࡁࡿࠋࡲࡓࠊ⎔ቃᨺᑕ⥺ࡢᙳ㡪ࢆ࡛ࡁࡿࡔࡅୗࡆࡿࡓࡵࠊ㖄ᯈ࡛࠶ࡿ

Fig. 1 Schematic representation of removal device⛬ᗘࡢ㐽ⶸࢆࡋࡓࠋ ᐃᆅࡢ⎔ቃᨺᑕ⬟ࡣ 0.06㹼0.08 μSv/h⛬ᗘࡔࡀࠊ㐽ⶸ࡟ࡼࡗ࡚ࣈࣛࣥࢡࢆ 0.03 μSv/h ⛬ᗘ࡟ୗࡆࡿ

― 140 ―

ࡇ࡜ࡀ࡛ࡁࡓࠋ ᐃࡣ 20 ⛊࠾ࡁ࡟ 15 ศ㛫グ㘓ࡋࠊ୙Ᏻᐃ࡞

࠺࡟ࡋࡓࠋࡑࡢ⤖ᯝࠊᚠ⎔ᾮ࡟ṧࡗࡓᨺᑕ⥺㔞ࡣࡸࡣࡾ 3 %᭱ึࡢ 5 ศ㛫ࢆ㝖࠸ࡓṧࡾࡢ 10 ศ㛫ࢆᖹᆒࡋࡓࠋ

⛬ᗘࠊᚤ⢊ࡣ 20 %࡜࡞ࡗࡓࡀࠊ᧯సࡢᡭ㡰࡟ࡼࡗ࡚ࡢኚືࡶࡇࡢ ᐃ࢟ࢵࢺࢆ⏝࠸ࡿ࡜ࠊ ᐃࡉࢀࡿ μSv/h ࠿ࡽ࣋ࢡࣞ኱ࡁ࠸ࡢ࡛ࠊ᫂☜࡞ᕪ࡜ࡣゝ࠼࡞࠸࠿ࡶࡋࢀ࡞࠸ࠋ

ࣝ㔞ࢆ኱ࡲ࠿࡟᥎ᐃ࡛ࡁࠊ᥮⟬⏝ࢢࣛࣇࡀ࣓࣮࣮࢝ࡼࡾᥦ౪ࡉ

୍᪉ࠊᚠ⎔ᾮ࡟㓑㓟࢔ࣥࣔࢽ࣒࢘ࢆ⏝࠸ࡿ࡜ࠊ᫂ࡽ࠿࡟ᚠ

ࢀ࡚࠸ࡿࠋࡋ࠿ࡋࠊ᥮⟬ࡢጇᙜᛶ࡟㛵ࡋ࡚ࡣࡲࡔ༑ศ࡞ࢹ࣮ࢱ⎔ᾮ࡟ᅇ཰ࡉࢀࡿᨺᑕ⥺㔞ࡀቑ࠼ࠊ୍㒊ࡢࢭࢩ࣒࢘ࡀྍ⁐໬ࡀᚓࡽࢀ࡚࠸࡞࠸࡜ᛮࢃࢀࡿࠋࡲࡓࠊμSv/h ࡢ್ࡣᮏ᮶ࡣே

ࡋ࡚ࡁ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡓࠋࡇࢀࡣࠊᅵተࡢ࢖࢜ࣥ஺᥮య࡜

య࡟ᑐࡍࡿᙳ㡪ᗘࢆ⾲ࡋ࡚࠸ࡿࡢ࡛ࠊࡑࡢ್ࢆ┤᥋⾲グࡍࡿ

ࡋ࡚ࡢᛶ㉁࡟ࡼࡗ࡚྾╔ࡋ࡚࠸ࡓࢭࢩ࣒࢘ࡀࠊ㧗⃰ᗘࡢሷ࡟ࡇ࡜ࡣṇ☜࡜ࡣ࠸࠼࡞࠸ࠋࡑࡇ࡛ࠊ௒ᅇࡣᚓࡽࢀࡓ μSv/h ࡢࡼࡾ⁐ฟࡋ࡚ࡁࡓࡶࡢ࡜⪃࠼ࡽࢀࡿࠋࡇࡢᐇ㦂࡛ࡣᚠ⎔ᅇᩘ್࠿ࡽࠊᨺᑕᛶ≀㉁ࡀᚠ⎔ᾮࡸᚤ⢊➼࡟࡝ࡢࡼ࠺࡟⛣ືࡋࡓ

ࢆ 3 ᅇ࡜ࡋ࡚࠸ࡿࡢ࡛ࠊᚤ⢊࡟ᅇ཰ࡉࢀࡓᨺᑕ⥺㔞ࡶከࡃࠊ࠿ࢆẚ⋡࡛⾲⌧ࡍࡿࡇ࡜࡟ࡋࡓࠋࡇࡢ ᐃ࡛ࡣࠊᚠ⎔ᾮࠊᚤᅇ཰ࡉࢀࡓ⥲㔞ࡶ 42 %࡜࠿࡞ࡾࡢ㔞࡟࡞ࡿࡀࠊ㉁㔞࡜ࡋ࡚ᅇ⢊ࠊṧ´ࡢᨺᑕ⥺ࡢ್ࢆྜィࡍࡿ࡜ࠊᴫࡡඖࡢヨᩱࡢ஝⇱ᚋ཰ࡉࢀࡓࡢࡣ 18 %⛬ᗘ࡛ẚ㍑ⓗຠ⋡ࡼࡃᨺᑕᛶ≀㉁ࢆᅇ཰ࡋ

ࡢᨺᑕ⥺㔞࡟┦ᙜࡍࡿࡇ࡜ࡣ☜ㄆ࡛ࡁࡓࠋᨺᑕ⬟ᅇ཰⋡ࡣᚠ࡚࠸ࡿࠋࡇࡢ࡜ࡁయ✚ࡣ஝⇱ᚋ⣙ 25 mL ࡛࠶ࡾࠊ200 g ࡢᅵ⎔ᾮࠊᚤ⢊ࠊṧ´ࡢᨺᑕ⬟್ࡢྜィ࡟ᑐࡍࡿẚ⋡࡜ࡋࡓࠋ㉁ተࡣ 250㹼300 mL ࡛࠶ࡿࡢ࡛⣙ 1/10 ࡜࡞ࡗ࡚࠸ࡿࠋ㔞ᅇ཰⋡ࡣᚤ⢊࡜ṧ´ࡢ㉁㔞ྜィ࡟ᑐࡍࡿẚ⋡࡜ࡋࡓࠋ୍᪉ࠊ㝖ᰁࡢຠ⋡ࢆୖࡆࡿࡓࡵ࡟ࡣࠊᚠ⎔ࡢ᫬㛫ࡣ▷࠸࡟㉺ࡋࡓࡇ࡜ࡣ࡞࠸ࠋࡑࡇ࡛ࠊ5 ศ㛫 1 ᅇࡢᚠ⎔࡛࡝ࡢ⛬ᗘࡢ㝖3㸬⤖ᯝཬࡧ⪃ᐹ
㸦1㸧ࣔࢹࣝ⿦⨨ࡢᙧែཤࡀྍ⬟࠿ࢆ᳨ウࡋࡓ㸦Table 2㸧ࠋࡑࡢ⤖ᯝࠊᚠ⎔୰࡟ࣃ࢖ ௒ᅇࠊ࢞ࣛࢫ〇ࡢᐜჾ࡟ᅵተࢆධࢀࡓࡢ࡛ࠊഃቨࡀᏑᅾࡋ

㛫 3 ᅇࡢ 29 %࡟㏕ࡿࡃࡽ࠸ࡢᅇ཰⋡ࢆᚓࡿࡇ࡜ࡀྍ⬟ࡔࡗ࡚࠸ࡿࠋᐇ㝿࡟⌧ሙ࡛⏝࠸ࡿ࡜ࡍࢀࡤࠊሷ⁐ᾮࡀὶฟࡋ࡞࠸ࡓࡀࠊᚠ⎔ᾮ࡟⁐ฟࡋࡓᨺᑕᛶ≀㉁ࡣᑡ࡞ࡃࠊ࢖࢜ࣥⓗ࡟྾ࡼ࠺ࠊ⿦⨨ࡢ࿘ࡾ࡟ഃቨࢆ❧࡚ࡿࡇ࡜ࡀᚲせ࡜ᛮࢃࢀࡿࡀࠊ╔ࡋ࡚࠸ࡿࢭࢩ࣒࢘ࢆᚠ⎔ᾮ࡟ྍ⁐໬ࡉࡏࡿ࡟ࡣ࠶ࡿ⛬ᗘ௨

ᅄゅ࠸ഃቨࢆᅵተࡢୖ࡟࠾࠸࡚࠾ࡃ⛬ᗘ࡛඘ศ࡛ࡣ࡞࠸࠿࡜

ୖࡢ᫬㛫ࡀᚲせ࡜ᛮࢃࢀࡓࠋࣉࢆ᣺ືࡉࡏࡿ࡞࡝ࡍࡿ࡜ࠊᚤ⢊ᅵተࡢᨺᑕ⬟ᅇ཰⋡ࡣ 1 ᫬ᛮࢃࢀࡿࠋ

௨ୖࡢ⤖ᯝࡣࠊࡇࡢ᪉ἲࡀࠊởᰁࡢ᏶඲㝖ཤ࡟ࡣཬࡤ࡞࠸rofytei
coSe
htefvoitlcaanoriutdonaeR©Jfmononrioiv
tnaiEdeehtni
RemnoitanimatCon
㸦2㸧ᨺᑕᛶ≀㉁ࡢᅇ཰
 3 ✀㢮ࡢᚠ⎔ᾮࢆ⏝࠸ࡓ⤖ᯝࢆ Table 1 ࡟♧ࡍࠋࡲࡎࠊᚠ
⎔ᾮ࡟Ỉ㐨Ỉࢆ⏝࠸ࡓሙྜࠊᚠ⎔ᾮ࡟ࡣ඲యࡢᨺᑕ⬟ࡢ 3 %ࡀᅇ཰ࡉࢀࡓࠋ୍᪉ࠊᚤ⢊ᅵተࡣ㉁㔞࡛ 8 %⛬ᗘᅇ཰ࡉࢀࡓ
ࡀࠊᨺᑕ⬟ࡣ 16 %ྵࡲࢀ࡚࠸ࡓࡢ࡛༢఩㉁㔞࠶ࡓࡾࡢᨺᑕ⥺࡜ࡋ࡚ࡶࠊᗈ኱࡞ởᰁ㠃✚ࢆ㝖ᰁࡋ࡚࠸ࡃຠ⋡ⓗ࡛⌧ᐇⓗ࡞㔞ࡀ㧗࠸ࡇ࡜ࡀ♧ࡉࢀࡓࠋࡇࢀࡣࠊࡇࢀࡲ࡛ࡢሗ࿌࡜ࡼࡃᑐ⌧ᆅ࡛ࡣࠊ㎰ᆅࡢ㝖ᰁࢆࡋ࡚ࡶࡋࡤࡽࡃࡍࡿ࡜࿘㎶ࡢᒣᆅ࠿ᛂࡋ࡚࠸ࡿࠋࡽᨺᑕᛶ≀㉁ࡀὶࢀ㎸ࡴࡇ࡜ࡀၥ㢟࡜࡞ࡗ࡚࠸ࡿࡀࠊࡇࡢ⿦ᡭẁ࡜࡞ࡿྍ⬟ᛶࢆᣢࡗ࡚࠸ࡿࡇ࡜ࢆ♧ࡋ࡚࠸ࡿࠋởᰁᅵተࡑࡢࡶࡢࢆ⛣ືࡍࡿࡇ࡜࡞ࡃࠊ⌧ᆅ࡟タ⨨ࡋࠊ⛣ືࡋ࡞ࡀࡽ㝖ᰁࢆ㐍ࡵࡿ⿦⨨ࢆ〇సࡍࢀࡤࠊ᫬㛫ࡣ࠿࠿ࡿ࡜ࡋ࡚ࡶࠊ㝖ᰁࢆ╔ᐇ࡟㐍ࡵࡿᡭẁ࡟࡞ࡿࡢ࡛ࡣ࡞࠸ࡔࢁ࠺࠿ࠋ౛࠼ࡤࠊḟ࡟ࠊᚤ⢊ᅵተࢆᅇ཰ࡋ᫆࠸ࡼ࠺࡟Ỉ㐨Ỉ࡟࢔ࣝࢠࣥ㓟ࢆ⨨ࢆ㎰ᶵල࡜ࡋ࡚ࡲ࡜ࡵࡿࡇ࡜ࡀ࡛ࡁࢀࡤࠊྛ㎰ᐙࡀẖᖺ⪔⁐࠿ࡋ࡚ᚠ⎔ࡉࡏࠊᅇ཰᫬࡟࢔ࣝࢠࣥ㓟ࢆሷ໬࢝ࣝࢩ࣒࡛࢘స㛤ጞ๓࡟㝖ᰁసᴗࢆ⾜࠸ࠊᏳ඲࡟⪔సࢆ⾜࠺ࡇ࡜ࡀ࡛ࡁࡿจ㞟ࡉࡏࠊࡇࡢ࡜ࡁࡈࡃ⣽࠿࠸ᚤ⢏Ꮚࢆ୍⥴࡟ỿẊࡉࡏࡿࡼࡼ࠺࡟ࡍࡿࡢࡶ୍᱌࠿ࡶࡋࢀ࡞࠸ࠋ



Table 1 Distribution of radioactive material after the circulation processᚠ⎔ᾮᚠ⎔ᅇᩘỈ㐨Ỉ

2࢔ࣝࢠࣥ㓟⁐ᾮ

20.5M 㓑㓟࢔ࣥࣔࢽ࣒࢘㸩࢔ࣝࢠࣥ㓟3ヨᩱᚠ⎔ᾮᚤ⢊ᅵተṧᏑᅵተᚠ⎔ᾮᚤ⢊ᅵተṧᏑᅵተᚠ⎔ᾮᚤ⢊ᅵተṧᏑᅵተ
― 141 ―ᨺᑕ⬟ᅇ཰⋡㸦%㸧 ㉁㔞ᅇ཰⋡㸦%㸧

31681
32077
1329
58-8
92-1387-1882


Table 2 Distribution of radioactive material after 5 min circulationᚠ⎔ᾮᚠ⎔ᅇᩘヨᩱᨺᑕ⬟ᅇ཰⋡
㸦%㸧㉁㔞ᅇ཰⋡㸦%㸧㓑㓟࢔ࣥࣔࢽ࣒࢘㸩࢔ࣝࢠࣥ㓟1ᚠ⎔ᾮᚤ⢊ᅵተṧᏑᅵተ22672-1585

ཧ ⪃ ᩥ ⊩㻠㸧 ➉ୗ೺஧ࠊ㧗ᶫ⚽἞ࠊ᭱ୖせࠊ▼ᇽ᫛ኵ㸸⎔ቃᨺᑕ⬟㝖㻝㸧 ሯ⏣⚈ᩥࠊᒣཱྀ⣖Ꮚࠊ㧗ᶫ▱அ㸸໬Ꮫ࡜⏕≀ࠊ49, 834-842

ᰁᏛ఍➨ 1 ᅇ◊✲Ⓨ⾲఍せ᪨㞟ࠊ1, 27 (2012)㻌

(2011)㻌

㸧 ୕ᾆၨ୍ࠊᮏ㛫೺୍ࠊబࠎᮌᛅᚿࠊᮌᮧṊࠊ┿ಖ⚅㸸⎔ቃᨺᑕ⬟㝖ᰁᏛ఍➨  ᅇ◊✲Ⓨ⾲఍せ᪨㞟ࠊ
1, 81 (2012)

㻞㸧 ⚟ᓥṇࠊすஂಖ຾ࠊ㉥஭ⰾᜨࠊ୕಴㏻Ꮥࠊᐑᮏ┿ဢ㸸⎔ቃᨺᑕ⬟㝖ᰁᏛ఍➨ 1 ᅇ◊✲Ⓨ⾲఍せ᪨㞟ࠊ1, 87㻌(2012)㻌 㻌㻌㻟㸧 ᮌୗဴ୍ࠊ㇂ᮏ♸୍㸸⎔ቃᨺᑕ⬟㝖ᰁᏛ఍➨ 1 ᅇ◊✲Ⓨ

2012 ᖺ 9 ᭶ 18 ᪥ཷ௜㻌2013 ᖺ 9 ᭶ 1 ᪥ཷ⌮㻌⾲఍せ᪨㞟ࠊ1, 19 (2012)㻌



࿴ᩥせ⣙
㻌 ⾲ᅵࢆ㝖ཤࡍࡿࡇ࡜࡞ࡃࠊ⌧ᆅ࡛ᨺᑕᛶࢭࢩ࣒࢘ࢆຠ⋡ⓗ࡟ᅇ཰ࡍࡿ᪉ἲ࡟ࡘ࠸᳨࡚ウࡋࡓࠋᅵተ୰ࡢࢭࢩ࣒࢘ࡢ࠺ࡕࠊ࢖
࢜ࣥ஺᥮ྍ⬟࡞≧ែࡢࡶࡢࢆࠊᅵተ࡟ሷ⁐ᾮࢆᚠ⎔ࡉࡏࡿࡇ࡜࡟ࡼࡾྍ⁐໬ࡋࡓࠋᚠ⎔࡟ࡣ 0.5 M 㓑㓟࢔ࣥࣔࢽ࣒࢘ࢆ⏝࠸

rofyteicoSehtefvoitlcaanoriutdonaeR©JfmononrioivtnaiEdeehtni
Remnoitani
matConࡓࠋ୍᪉ࠊᅵተ࡟ᙉᅛ࡟⤖ྜࡋࡓࢭࢩ࣒࢘࡟ࡘ࠸࡚ࡣࠊከࡃࡢࢭࢩ࣒࢘ࡀ྾╔ࡋ࡚࠸ࡿ⾲㠃✚ࡀ኱ࡁ࠸⢏Ꮚᚄࡢᑠࡉ࡞ࡶࡢ
ࢆྠ᫬࡟ᅇ཰ࡍࡿࡇ࡜࡛ຠ⋡ⓗ࡟㝖ཤࡍࡿࡇ࡜ࢆヨࡳࡓࠋከᩘࡢࣃ࢖ࣉ࠿ࡽሷ⁐ᾮࢆᅵተ୰࡟ὀධࡋࠊᅵተ⾲㠃࡟ᾐฟࡋ࡚ࡁࡓ⁐ᾮࢆ྾ධ⏝ࣃ࢖ࣉ࡛྾࠸ࡇࡳᚠ⎔ࡉࡏࠊὶฟࡋ࡚ࡁࡓᅵተᚤ⢏Ꮚࢆᅇ཰ࡋࡓࠋᚠ⎔᫬㛫ࡣ㸯᫬㛫࡜ࡋࠊࡇࢀࢆ 2㹼3ᅇ⾜ࡗࡓࠋࢁᾮࠊᚤ⢏Ꮚࠊṧࡗࡓᅵተ࡟ศࡅࠊࢁᾮࡣࡑࡢࡲࡲࠊᚤ⢏Ꮚ࡜ᅵተࡣ 140ºCࠊ20 ᫬㛫஝⇱ࡋ࡚஝⇱㉁㔞ࢆ ᐃࡋࡓᚋ࡟ᨺᑕ⬟ࢆ ᐃࡋࡓࠋᚠ⎔ᾮ࡟Ỉࢆ⏝࠸ࡓሙྜྍ⁐໬ࡋ࡚ࡃࡿᨺᑕ⬟ࡣ 3 %⛬ᗘ࡜࠶ࡲࡾከࡃࡣ࡞ࡃࠊᚤ⢏Ꮚ࡜ࡋ࡚ᅇ

཰ࡉࢀࡓᅵተ࡟ࡣ 16 %⛬ᗘࡢᨺᑕᛶ≀㉁ࡀྵࡲࢀࡓࠋᚠ⎔ᾮ࡟㓑㓟࢔ࣥࣔࢽ࣒࢘࡜࢔ࣝࢠࣥ㓟ࢆ⏝࠸ࡿ࡜ࠊᚠ⎔ᾮ࡟ 12 %ᅇ཰ࡉࢀࠊ⥲㝖ཤ⋡ࡣ 42 %࡛ࠊࡇࡢ࡜ࡁ㝖ཤࡉࢀࡓᚤ⢏Ꮚࡢ㉁㔞ࡣ඲యࡢ 18 %࡛࠶ࡗࡓࠋࡇࡢࡇ࡜ࡣࠊᅇ཰ࡉࢀࡓᚤ⢏Ꮚ࡟ࡼࡾከࡃࡢᨺᑕᛶ≀㉁ࡀ྾╔ࡋ࡚࠸ࡿࡇ࡜ࢆ♧ࡋ࡚࠸ࡿࠋ㻌

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