The Leningrad NPP currently operates four units: units 3 and 4 with RBMK-1000 reactors, and units 5 and 6 with modern VVER-1200 reactors, known as Leningrad-II units 1 and 2. Units 5 and 6 replaced the decommissioned units 1 and 2, shut down in 2018 and 2020, respectively. Units 7 and 8, also VVER-1200, are planned to replace units 3 and 4. The first concrete pour for unit 7 was completed ahead of schedule.
Builders are currently reinforcing the foundation for the unit 7 cooling tower. The foundation will require approximately 1,500 tonnes of reinforcement bars, ranging from 8 to 40 millimeters in diameter, and about 5,500 cubic meters of concrete. A nearby concrete plant ensures efficient delivery of the concrete mixture to the site.
The concrete is made using Portland cement, known for its high waterproofing, frost resistance, and durability. This material is commonly used in constructing critical infrastructure such as subways, dams, and bridges.
“High-grade concrete, coupled with a rigid reinforced frame, as well as a pre-made base of 760 drilling piles, will be a reliable support for the 179-metre-high cooling tower and the equipment placed inside it,” said Evgeny Milushkin, Deputy Director for Capital Construction and Head of the Capital Construction Department of Leningrad-II NPP. “In addition to the ring foundation for the tower, this year will see construction of separate foundations for each of the 50 pillars of the reinforced concrete inclined colonnade of the cooling tower and the foundation and walls for its drainage basin.”
Construction of the cooling tower’s main structure is scheduled to begin next year. A tower crane will be installed inside the tower to facilitate concreting, and self-lifting sliding formwork will be used to streamline the process. This formwork allows continuous concrete pouring without disassembly, enhancing the tower’s monolithic structure and overall strength.
Currently, Leningrad-II operates two evaporative cooling towers: one 150 meters tall for unit 5 and another 167 meters tall for unit 6.
