Investigations to increase the efficiency of fluorine and boron removal from groundwater using radiation-induced graft polymerization adsorbent

Iyatomi, Yosuke ; Hoshina, Hiroyuki; Seko, Noriaki; Shimada, Akiomi; Ogata, Nobuhisa ; Sugihara, Kozo; Kasai, Noboru; Ueki, Yuji; Tamada, Masao

The Mizunami Underground Research Laboratory (MIU) Project is a research project investigating the deep underground environment within crystalline rock being conducted by JAEA. The concentrations of fluorine and boron dissolved in groundwater pumped from shafts during excavation of geoscientific studies at MIU, are reduced to the levels below the environmental standards at a water treatment facility. Coagulation treatment and ion exchange treatment are applied for fluorine and boron respectively. So we have started to research on efficient groundwater treatment for fluorine and boron using radiation-induced graft polymerization adsorbent. Regarding the treatment for boron, the processing that about 12 times were faster than the general ion exchange resin was possible and the use of the adsorbent was possible repeatedly. In addition, it developed that the pH of the underground water gave adsorption performance of adsorbent influence. With respect to fluorine removal, fluorine adsorption more than 90% was able to confirm by the adsorbent, but low value in comparison with boron. As the reason, a difference of the concentration of fluorine and boron in groundwater is thought about. It is necessary to grasp the concentration which adsorption performance can show enough.