In 2022, the BN-800 fast reactor at unit 4 of Russia’s Beloyarsk nuclear power plant will completely switch to uranium-plutonium mixed oxide (mox) fuel.
This will be an important step towards closing the nuclear fuel cycle, Beloyarsk NPP said in a statement.
The transition is scheduled to start in the first half of 2021 when mox fuel assemblies are installed in one-third of the reactor core.
When BN-800 began commercial operation in 2016, it had a hybrid core comprising both uranium fuel produced by Mashinostroitelny Zavod in Elektrostal and mox assemblies manufactured at the Research Institute of Atomic Reactors (NIIAR) in Dimitrovgrad.
“The BN-800 reactor is to be transferred from a hybrid core to a core with a full load of fuel assemblies with mox pellet fuel,” said Vladimir Shaloumov, head of the department of nuclear safety and reliability at the Beloyarsk NPP. "The BN-800 reactor is targeted to use mox fuel as one stage on the path towards developing a closed nuclear fuel cycle for domestic nuclear energy.”
Mox fuel for Beloyarsk 4 is fabricated at Russia's Mining and Chemical Combine in the Krasnoyarsk Territory, Shaloumov said. The first batch of fuel was produced by MCC in 2018.
The goal is to obtain a full mox core in the first half of 2022.
On 10 June, the Beloyarsk plant announced a milestone in import substitution when German mechanical seals were replaced with domestic graflex products manufactured by UNIHIMTEC in one of the main feed pumps of the BN-800.
“The mechanical seals of pumps are consumables, which must be periodically replaced,” said Ilya Filin, deputy chief engineer for operation at Beloyarsk 4.
“We received a change in the terms of the licence from Rostekhnadzor for the operation of unit 4, allowing the pilot operation [with] the mechanical seal [from] the Russian manufacturer on one of the main feed pumps," he added.
The new seals will be tested for 8000 hours, after which a decision will be made on replacing the seals on the other seven pumps in Beloyarsk 4.
The seal replacement project was carried out as part of a policy of import substitution announced by President Vladimir Putin.
Photo: The first batch of mox fuel for the BN-800 was produced in 2018 (Photo credit: TVEL)