Sunday, July 22, 2018

Closed nuclear fuel cycle is being followed in India treating spent nuclear fuel as a material of resource instead of nuclear waste. The closed fuel cycle aims at recovery and recycle of fuel elements, separation of useful isotopes such as Cs (Caesium) and Sr (Strontium) for use in health care and industry. The spent fuel is reprocessed to recover the fuel elements like Uranium and Plutonium for recycling back in the reactor for generation of power in second stage of Indian nuclear power programme.

This finally leads to a very small percentage of residual material present in spent nuclear fuel requiring their management as radioactive waste. Radioactive waste contains various useful radio-isotopes like Cs-137, Sr-90, Ru-106 (Ruthenium) having different societal applications. An in-house developed technology has been established and deployed for separating Cs137, one of the prominent fission product, from waste and converting in to non-dispersive Cs glass pencil to be used for blood irradiators.

Research and development has been carried out for reprocessing spent nuclear fuel and recycling back to reactors as fuel. Fast Breeder Test Reactor (FBTR), utilizing reprocessed spent fuel, is under operation since many decades.

The quantity of waste will depend on the power generation. In general, only 1% of the fuel originally used becomes waste as rest is reused. Even this 1% comes down further when radioisotopes like Cs-137 are taken out and used in irradiators.