Refrigeration to the rescue?16th August 2013
JAPAN: Refrigeration could come to the rescue of the Tsunami-hit Fukushima nuclear plant which is still spewing contaminated water into the sea more than two years after the disaster.
Ground-freezing technology used in the building of dams and mines could be called upon to stem the seepage into the land and sea from the 300 tons of radiation contaminated water, which is pumped into the reactors every day in an effort to cool them.
Most of the water is recycled but a significant amount still seeps away despite an underground barrier built to try to prevent the contaminated groundwater from reaching the sea.
Now the Tokyo Electric Power Company responsible for the site is considering spending upwards of $400m to create and maintain what would be a mile long stretch of artificial frozen earth. According to the Japan Daily Press it would require 9.8MW of power to maintain.
Contrary to many reports in the Japanese press the technology has been tried and tested over more than 100 years. Freezing the ground as a means of providing temporary earth support and ground water control has been used in the mining industry and it is debatable whether either the famous Coulee and Hoover Dams would ever have been constructed without the use of ground freezing. In the case of the Coulee Dam, pipes were driven into the earth and fed by an ammonia/brine refrigeration system. Similar techniques are still used today.