The 3rd and the 4th power units Leningrad NPP has commenced the activities on nuclear fuel afterburning for the 1st power block that has been discontinued and is preparing for shutdown. These activities were stipulated by the introduction of the irradiated fuel assembly afterburning technologies, which is used by the operating 3rd and 4th power units to process the fuel from the 1st and the 2nd power units that have been discontinued. Based on the results of the technical and economic analysis, those fuel assemblies that haven’t reached a half of their fuel burnout planned depth will be used for afterburning. 

The implementation of the nuclear fuel afterburning technology for the discontinued Leningrad NPP units will help to save around 1,000 fresh fuel assemblies. This will also increase the fuel usage assembly by achieving the fuel burnout planned depth and reduce the number of assemblies used for power unit operation and demanding expensive maintenance: the transportation and long-term storage at the on-site storehouse, transition to dry storage and sending to long-term storage or recycling to specialized companies.

In order to facilitate the safest and the most effective afterburning technology, a complex transportation and technology workflow for nuclear fuel, technical evaluation of safety for the sequence of operation, all the necessary design and engineering documentation, development of operational manuals, staff training and other activities have been carried out.

‘Our work fully complies with the standards and the requirements applicable to nuclear power. A set of documents confirming safety of the nuclear fuel afterburning technology and its compliance with the standards has been reviewed by the nuclear and radiation safety R&D center. Based on the review outcomes, Rostekhnadzor has issued corresponding license changes that let the operating organization work in the realm of nuclear power usage’, Igor Lozhnikov, the deputy chief engineer of the Leningrad NPP, said.

Rosenergoatom Joint-Stock Company, the operating organization, has decided to deploy the nuclear fuel afterburning technology across other RBMK-1000 NPPs in Russia.

It is important to note that the 1st power unit was discontinued in 2018 to get prepared for the shutdown. The Leningrad NPP 2nd power unit is to be fully shutdown early November 2020.