Development of Innovative Treatment Technology for Removal of Radioactive Cesium in Designated Wastes

2017 Fiscal Year Final Research Report

• Project/Area Number: 26241022
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Environmental engineering and reduction of environmental burden
• Research Institution: Osaka Sangyo University
• Principal Investigator: OZAKI HIROAKI 大阪産業大学, 工学部, 教授 (40135520)
• Co-Investigator(Kenkyū-buntansha): 高浪 龍平 大阪産業大学, デザイン工学部, 講師 (00440933) ; 山田 修 大阪産業大学, 工学部, 教授 (10140203) ; 李 玉友 東北大学, 工学研究科, 教授 (30201106) ; 櫻井 伸治 大阪府立大学, 生命環境科学研究科, 助教 (30531032) ; 谷口 省吾 大阪産業大学, 工学部, 契約助手 (40425054) ; 藤長 愛一郎 大阪産業大学, 工学部, 教授 (40455150) ; 藤川 陽子 京都大学, 原子炉実験所, 准教授 (90178145) ; 津野 洋 大阪産業大学, 人間環境学部, 特任教授 (40026315)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 放射性セシウム除去 / 指定廃棄物 / 下水汚泥 / フェロシアン化法 / 非イオン性放射性セシウム / シュウ酸抽出 / 共沈除去 / オゾン/過酸化水素添加

Outline of Final Research Achievements

In the aftermath of the accident of 2011 Fukushima Daiichi Nuclear Power Plant, sewage sludge and municipal solid waste contaminated with radioactive cesium (rad-Cs hereafter) has been produced in 12 Prefectures. We have investigated a technique that can reduce the volume of fly ash from melting furnace and incinerator of sewage sludge by extracting and co-precipitating and concentrating rad-Cs in a small amount of hexacyanoferrate precipitate. We have conducted on-site tests at a sewage treatment plant in north of the Kanto district. Notably, fly ash from melting furnace contained more water soluble rad-Cs than that of incinerator. The removal of Cs from the extract by hexacyanoferrate co-precipitation was high (>95 %) except for oxalic acid extract of incinerator fly ash. We conducted ultra-filtration of the extract at one of the on-site tests, and found that part of rad-Cs in the extract was colloid, and therefore could not be coprecipitated by hexacyanoferrate.

Free Research Field

環境工学