Rosatom has installed eight hydraulic tanks - part of the second stage of the reactor passive core flood protection system - at unit 2 of the Kursk-II NPP. Earlier, in June, four hydraulic tanks of the first stage of the emergency core cooling system (ECCS) were installed. “The tanks, which will subsequently be filled with a solution of boric acid, are designed to cool the reactor core in any emergency situations, Andrey Osharin, First Deputy Director for Construction of New Units of the Kursk NPP, explained. “The joint sequential operation of the three stages of hydro-accumulators ensures the cooling of the reactor core and guarantees the transition of the reactor plant to a safe state in any combination of initiating events.”
Each hydraulic capacity of the passive core flooding system is a vessel over 10 metres high, weighing 77 tons and having a volume of 120 cubic metres. Their installation is particularly complex. The installation was carried out by the specialised installation organisation JSC Energospetsmontazh, which is part of JSC ASE, the Engineering Division of Rosatom. The tanks are installed at a height of 26.3 metres - the ceiling of the central hall.
“For the first time, the installation of the tanks of the passive core flooding system was carried out in parallel with the sectoral concreting. This reduces the time needed for the installation of the inner containment dome. This was a team effort of our subsidiaries: Trest RosSEM LLC and Energospetsmontazh JSC", said Oleg Shperle, Vice President, Project Director for the construction of the Kursk NPP of JSC ASE.
Installation of the dome at unit 2 paves the way for the adjustment and commissioning of the circular crane (polar), as well as for beginning installation of the main technological systems and preparations for the installation of the reactor pressure vessel.
Kursk-II 1&2 are being built according to the VVER-TOI project (standard optimised informatised pressurised water power reactor), which is a development of the VVER-1200 reactor design with increased capacity and improved technical and economic indicators. Kursk II is intended as a replacement station for the currently operating Kursk NPP, which comprises four RBMK reactors. Unit 1 was closed in 2021 and unit 2 is to close in 2024. Originally the commissioning of Kursk-II units 1&2 was meant to coincide with the closure of Kursk 1&2.
Image: Installation of hydraulic tanks at Kursk-II (courtesy of Rosatom)
