Indigenous nuclear reactor set to touch a milestone

Argon buffer tank being erected at Kalpakkam nuclear enclave in Tamil Nadu.

India's first indigenously designed breeder reactor - which breeds more material for a nuclear fission reaction than it consumes - is being built by Bhavini at the Kalpakkam nuclear enclave, 80 km from here.

Lowering of the huge stainless steel main vessel -- 12.9 metres in diameter and 12.94 metres in height, weighing 206 tonnes -- is considered a major step in completing the 500 MW power project by the September 2011 deadline.

"We are in the process of creating 100 percent clean environment around the reactor vault so that the main vessel can be lowered inside the already erected safety vessel. The nuclear vault chamber has been air-conditioned," project director Prabhat Kumar told IANS.

As civil works are on in the building housing the reactor vault, officials do not want to risk even a speck of dust inside the main vessel that would hold the coolant liquid sodium, reactor fuel, grid plates and others.

The sodium-cooled fast reactor designed by the Indira Gandhi Centre for Atomic Research (IGCAR) has three vessels - a safety vessel, a main vessel and an inner vessel.

Outermost is the stainless steel safety vessel, which was lowered into the reactor vault last June - the first milestone.

The third and smallest of the three vessels is the inner vessel -- 11 metres tall. It houses pumps, heat exchangers and other equipment. Together, they all go inside the main vessel.

Activities connected with the erection of the main vessel - drawing up the scheme for lifting the vessel, other mock up activities, load testing - have commenced at the project site despite the threat of rain. The officials have kept a two-day window for the operation which should not take over three hours.