A new way to remove cesium ?

February 24, 2012

New technology can remove 99.9 percent of radioactive cesium in soil

http://mdn.mainichi.jp/mdnnews/news/20120224p2a00m0na022000c.html

New technology that can remove up to 99.9 percent of radioactive cesium in contaminated soil has been developed, raising hopes for reducing radioactive waste in areas affected by the Fukushima nuclear disaster, it has been learned.

Taiheiyo Cement Corp. and the National Agricultural Research Center in Tsukuba, Ibaraki Prefecture, devised the groundbreaking technique to drastically cut cesium in contaminated soil. The soil left after the decontamination process can be used as construction materials for the recovery of disaster-stricken areas, such as aggregate concrete, according to the developers.

The method employs a small rotating furnace, in which cesium-tainted soil is mixed with calcium compounds to promote a reaction before the materials are heated at 1,350 degrees Celsius. The cesium separated from the tainted soil is then captured by filters.

When tested on contaminated soil in Fukushima Prefecture, the levels of radioactive cesium in the soil decreased from 67,300 becquerels per kilogram to 29 becquerels. Although the filters, tainted with cesium after the process, need careful handling, the method is expected to contribute to reducing the amount of radioactive waste.

If heavy oil is used as the heating source for the furnace, it will cost 50,000 yen to 60,000 yen per metric ton of contaminated soil for the operation, the developers said.

"We hope to contribute to minimizing the disposal sites for contaminated soil through such cost-cutting efforts as utilizing existing furnaces," said an official with the National Agricultural Research Center. "The method could also be applied to the disposal of fallen leaves and rice straw."

Click here for the original Japanese story