By IANS,
Chennai: Officials are mulling circulating coolant water in the first reactor of the Kudankulam Nuclear Power Project (KNPP) as the stagnant water in the reactor vessel and pipes is posing a corrosion risk.
“We are trying to circulate the coolant water in a small way. We can do some level of circulation,” a Nuclear Power Corporation of India Ltd (NPCIL) official told IANS on the condition of anonymity.
Work at the KNPP site came to a standstill last month after protests by villagers intensified on safety grounds. Roads have been blocked and the local administration has advised the KNPP staff to sit tight inside their homes, fearing violence.
The NPCIL by then had completed the hot run of the first reactor and was gearing up for loading the real fuel.
In nuclear power reactor parlance, hot run refers to the testing of reactor systems and pipelines using dummy fuel — which is similar to the real one but without uranium.
NPCIL is building two 1,000 MW nuclear power reactors with Russian technology and equipment in Kudankulam, around 650 km from here. The first unit is expected to go on stream in December.
Citing the completion of the hot run, NPCIL officials say the coolant water should be continuously circulated so that the pipelines and the reactor vessel are not damaged.
“There has to be some level of circulation and maintenance of water chemistry to avoid corrosion risk,” former Atomic Energy Regulatory Board (AERB) chairman S.K. Sharma told IANS.
Sharma is part of the 15-member committee formed by the centre to allay the fears of the anti-KNPP activists about the plant.
According to him, even though the fuel loading operations got interrupted by protests, there may not be a need for another hot run.
The NPCIL official said the hot run was complete in all aspects. The additional tests suggested by AERB are also over and only formal clearance is awaited from the regulator.
“From AERB’s point of view, every parameter has to be checked to make sure everything is alright. During the commissioning of a reactor, the regulator has laid down several check points,” Sharma said.
Speaking about the maintenance activities underway at the first unit, Sharma said the power turbine is rotated manually so that it’s kept in good shape.
“The generator to power the turbine motor was disconnected for maintenance. After that, the protests affected operations. The turbine has to be rotated very slowly so that its bearing and other parts are kept in good condition and the shaft does not sag. It needs 10 people to rotate the turbine,” the NPCIL official said.
Queried on the prudence of having multiple nuclear power reactors at one location, Sharma said: “It saves cost. If the safety standards are followed, then there will not be any problem.
“The regulator will see the reactors have the revised safety standards like automatic cooling of the core at times of blackouts.”