Japan plans underwater sponges to soak up uranium

Japan is drawing up innovative plans to extract uranium from seawater in an attempt to end the country's reliance on imports for nuclear power stations.

By Julian Ryall in Tokyo Published: 1:40PM BST 16 Jun 2009

Government-funded scientists have proposed placing huge "uranium farms" on the seabed, consisting of anchored sponges which soak up the element.
Dr Masao Tanada, of the Japan Atomic Energy Agency, has developed a fabric made primarily of irradiated polyethylene that is able to soak up the minute amounts of uranium – around 3.3 parts per billion – in the seawater.

The world's oceans contain an estimated 4.5 billion tons of uranium, around 1,000 times the amount that is known to exist in uranium mines.
Dr Tanada claims Japan's nuclear power industry could harvest the 8,000 tons it needs each year a year from the Kuroshio Current that flows along Japan's eastern seaboard.
"At the moment, Japan has to rely on imports of uranium from Canada and Australia, but this technology could be commercially deployed in as little as five years," he said.
Uranium supplies from conventional mining operations are expected to last for another 100 years, although further deposits are still to be discovered. Extraction, however, is expensive and damaging to the environment.
Dr Tanada hopes to secure funding to construct an underwater uranium farm covering nearly 400 square miles that would meet one-sixth of Japan's annual uranium requirements.
"Other countries are conducting similar research but none are as advanced as we are," he said. "We need to conduct more development research and be able to produce the adsorbent material on a large scale, but we could achieve this within five years."