The much-awaited ‘hot run' of the first of the 2 X 1,000 MWe reactors under construction as part of the Koodankulam Nuclear Power Project (KKNPP) commenced last Friday, indicating that this nuclear reactor may attain criticality within another five months provided the Atomic Energy Regulatory Board (AERB) is satisfied with the functioning of the hi-tech equipment of this reactor and gives its clearance on time.
As the AERB's clearance reached KKNPP on Friday morning, the ‘hot run', an important activity that will take place before the reactor is loaded with the real fuel assemblies made of enriched uranium, commenced immediately.
The ‘hot run' will involve heating the primary coolant water to the reactor's operating temperature of 280 - 300 degree Celsius. The reactor systems will be operated at the temperature at which it will operate when it has enriched uranium fuel bundles.
The process of ‘hot run' will take place with the dummy fuel assemblies, which were loaded into the reactor several months ago. The dummy fuel assemblies have the same configuration as the real fuel assemblies but have no enriched uranium inside. The reactor vessel houses 163 fuel assemblies.
“The ‘hot run' will validate the quality of the components we have installed so far inside the reactor, including the reactor pressure vessel, and a team of experts comprising representatives from KKNPP, AERB and Russian engineers will closely monitor the efficacy of the systems and look out for leaks in any part of the system, metallurgy reaction etc.
Once the ‘hot run' is successfully completed within 45 days, the AERB will certify the system, if their representatives are satisfied with the performance of the entire system, enabling us to go for the next step of removal of dummy fuel inside the reactor,” said a senior official of KKNPP, who did not want to be quoted.
Once the removal of dummy fuel is completed, which will take a minimum of 25 days, the mandatory pre-service inspection for about 30 to 45 days will be conducted.
“The AERB will constantly monitor all these activities and also to give its clearance prior to actual fuel loading, it will consume another 30 days. Precisely, the first reactor will attain criticality in five months from now, if everything goes as we plan” said the official.