Understanding of host minerals for radioactive cesium fixation and proposal for reasonable volume reduction of the contaminated soils

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H04222
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Earth system and resources engineering
• Research Institution: Hokkaido University
• Principal Investigator: Sato Tsutomu 北海道大学, 工学研究院, 教授 (10313636)
• Co-Investigator(Kenkyū-buntansha): 廣吉 直樹 北海道大学, 工学研究院, 教授 (50250486) ; 小暮 敏博 東京大学, 大学院理学系研究科(理学部), 教授 (50282728)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: セシウム / 汚染土壌 / 団粒 / 風化黒雲母 / 磁選

Outline of Final Research Achievements

Detail observations for the contaminated soils particles collected from different areas in Fukushima prefecture,percentage of the contaminated particles was limited to be only 0.3%.The contaminated particles were categorized to agglomerated weathered biotite, complex of organic matter and weathered biotite and weathered biotite.From the observation,the weathered biotite would be dominant host of radioactive cesium in Fukushima prefecture and supported by adsorption experiments.From our observation,spherical glass particles (so called "Cs ball") were not detected. Therefore, we can conclude that the host of radioactive cesium is the weathered biotite in Fukushima prefecture.Our laboratory experiments showed that the weathered biotite can be collected by magnet.After ball milling crushing and ultra sonic dispersion for agglomerated weathered biotite and complex of organic matter and weathered biotite, the contaminated particles would be efficiently collected by magnetic cobbing machine.

Free Research Field

環境鉱物学