The BN-800 fast reactor at unit 4 of Russia’s Beloyarsk NPP has for the first time been brought to 100% power with a full load of mixed oxide (MOX) fuel.

“According to the terms of the licence, after completion of the scheduled repairs and refuelling, unit 4 had to work for 300 hours at a power level of 85%,” explained plant director Ivan Sidorov. “The reactor passed this period of operation without any remarks, all the neutron-physical characteristics of the core are within the normal range. This means that the innovative fuel is working correctly, and the power unit is ready to reliably, safely and fully generate electrical and thermal energy,” he said.

During the refuelling outage, which took place in June-September, the entire BN-800 core was completely switched to uranium-plutonium MOX fuel for the first time. The raw materials for the production of MOX fuel pellets are plutonium dioxide, obtained during the processing of used fuel from traditional VVER reactors, and depleted uranium oxide (obtained by defluorination of uranium-238 hexafluoride), the so-called secondary "tails" of uranium enrichment.

Image: The BN-800 fast reactor at unit 4 of Beloyarsk NPP is brought to 100% power with a full load of MOX fuel (courtesy of Beloyarsk NPP)