Russia’s Mayak Production Association in Ozersk has finished processing the first batch of used nuclear fuel from Rostov NPP. Mayak began reprocessing nuclear fuel from VVER-1000 reactors as a pilot project. Now the plant will start to receive used fuel from other reactors of this type.
A VVER-1000 produces about 20t of used fuel every year. Containers with the used fuel from Rostov were delivered to Mayak by rail in a special train last December. Mayak recently completed extensive work to modernise and upgrade the equipment at the RT-1 reprocessing plant. This included adding a third technological line which made possible processing of the larger and longer fuel assemblies from VVER-1000s, as well as many other types of used fuel. Previously Mayak handled only fuel from the smaller VVER-440 reactors, the BN-600 fast reactor, some research reactors and some submarine fuel. In November for the first time it processed, on an industrial scale, uranium-beryllium used fuel from decommissioned submarines.
One of the main conditions set by regulators before Mayak could begin processing VVER-used fuel was to stop the discharges of liquid radioactive waste into storage reservoirs. The waste management system at RT-1 has therefore been upgraded with the commissioning in December 2016 of the electric-EP 500/5 oven which enables liquid radioactive waste vitrification. In 2016 the specialists at Mayak also developed design documentation for a new small-sized smelter for conditioning liquid high-level waste (HLW) in borosilicate glass as part of the planned new complex vitrification. The transition from the aluminophosphate to borosilicate glass will reduce by three times the volume of vitrified HLW from reprocessing used fuel, according to Mayak Deputy Director for Strategic Development Dmitry Kolupaev.