| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that: the fact that wide regions are contaminated by radioactive materials due to a nuclear power plant accident becomes a large social problem; ground surface sediment is scraped and removed as a decontamination method for reducing the amount of radiation in some areas; although a technology for removing radioactive cesium dissolved in water is established at present, a separation and removal method for radioactive cesium mixed in soil has not been established; the above-described scraping and removal of ground surface sediment results in discharge of a huge amount of soil because of wide regions; and reduction in contaminated soil to be discharged, of which disposal destination has not been decided at present, is an important subject. <P>SOLUTION: Contaminated sediment has been subjected to soil quality analysis. Accordingly, it has been proved that radioactive cesium which is a contaminating substance exists in a larger amount in fine particles (particularly, fine mica) in soil, and it has been confirmed that the amount of radiation is reduced by removing the fine particles. The fine particles float readily in a liquid because of their shape characteristic of thin plate and are readily attached to the surface of bubbles. A mica portion in the soil is removed by an inventive device for separating the mica portion by means of bubbles by utilizing its property, a method and a device for separating radioactive cesium-contaminating mica, thus reducing the amount of radiation of the sediment as well as the amount of sediment to be discharged. <P>COPYRIGHT: (C)2013,JPO&INPIT |
