The latest trouble at the water treatment system: the density of radioactive materials, reduced after Kurion's treament, shot up again after AREVA's treatment.
From Mainichi Shinbun (9/15/2011):
東京電力は15日、福島第1原発事故で生じた高濃度の放射性物質を含む汚染水を浄化して原子炉の冷却に使う「循環注水冷却システム」で、米キュリオン社の装置によって下がった放射性物質の濃度が、続いて仏アレバ社の装置を通すと上がるトラブルが起きたと発表した。アレバ社の装置が処理する高濃度の汚泥が流出した可能性もあり、原因を調べている。現在は、アレバ社の装置は止め、キュリオン社の装置だけで処理している。
TEPCO announced on September 15 that there was a trouble in the reactor cooling system that circulates water treated in the contaminated water treatment system. The density of radioactive materials that decreased after the treatment with Kurion's system increased after the treatment with AREVA's system. It is possible that highly radioactive sludge in AREVA's system leaked. TEPCO is investigating the cause. Currently, AREVA's system is stopped, and the treatment is done by Kurion's system alone.
東電が同日、両社の装置の処理能力を確認したところ、キュリオン社単独では汚染水の放射性物質の濃度が1立方センチ当たり数百万ベクレルから数百ベクレルまで下がったが、その汚染水を続けてアレバ社の装置で処理すると、逆に数十万ベクレルに上がった。
TEPCO looked at the treatment performance of both systems and found that Kurion's system had reduced the density of radioactive materials from several million becquerels/cubic centimeter to several hundred becquerels/cubic centimeter. However, when that treated water was further processed in AREVA's system, the density shot up to several hundred thousand becquerels/cubic centimeter.
東電は10月以降、キュリオン社とアレバ社の装置を組み合わせた浄化システムを止め、比較的故障が少ない東芝製の別の浄化装置「サリー」で汚染水を浄化する方針だ。
TEPCO plans to stop using Kurion-AREVA system starting October, and use Toshiba's SARRY exclusively for contaminated water treatment. SARRY has had a relatively small number of failures compared to Kurion's or AREVA's system.
TEPCO was working on both Kurion's and AREVA's system from September 13, replacing a pump at Kurion's and a stirrer in the coagulation settling unit at AREVA's. Maybe that had something to do with the problem. Maybe not. TEPCO is not very forthcoming, as you may have noticed over the past 6 months.