Rosatom starts utilizing radiotoxic waste in Beloyarsk NPP reactor

YEKATERINBURG. July 10 (Interfax) - Mixed oxide fuel assemblies containing americium and neptunium have for the first time been loaded into a fast-neutron BN-800 reactor at the Beolyarsk Nuclear Power Plant in Russia's Sverdlovsk region, the BNPP press office said.

"The Beloyarsk NPP Unit 4's BN-800 fast neutron reactor has for the first time been loaded with uranium-plutonium MOX fuel assemblies also containing so-called minor actinides, the most radiotoxic and long-lived components from irradiated nuclear fuel," the statement said.

The loading of fuel into the reactor core was approved by Russia's authorized regulator Rostechnadzor, the Federal Service for Environmental, Technological and Nuclear Supervision, which had confirmed the safety of innovative fuel assemblies. The power unit has resumed operation following planned maintenance.

The three lead-test MOX bundles containing americium-241 and neptunium-237 will undergo pilot operation at the BN-800 core during three micro-campaigns (approximately a year and a half).

"The next BN-800 reactor micro-campaign should experimentally confirm that it is possible to utilize minor actinides on an industrial scale. An advantage of fast neutron reactors is their ability to eliminate minor actinides and reduce the volume of radioactive waste from the entire infrastructure of the nuclear fuel cycle of NPP operation," said Ivan Sidorov, Director of the Beloyarsk NPP.

Scientists estimates the afterburning of minor actinides in closed nuclear fuel cycle would enable the radiation equivalence of uranium feedstock and nuclear waste to be isolated in only 300 years, i.e. 2,300 times faster than the 700,000 years it takes in open nuclear fuel cycle.

The technology for MOX fuel fabrication, including bundles with minor actinides, was developed by Rosatom's Fuel Division managed by TVEL JSC. Rosatom engineers had verified and validated 38 techniques for analytical control of the nuclear fuel properties for the project to manufacture MOX bundles with minor actinides deploying Mining and Chemical Combine in-house technology and industrial-scale equipment.

The bundles of MOX fuel with minor actinides, manufactured for a commercial large-scale fast reactor, are absolutely unique, which "demonstrates the fundamental technological possibility to accomplish the most important component of generation-IV nuclear power systems," said Alexander Ugryumov, Senior Vice President for Research and Development at TVEL JSC.

"The service for minor actinides afterburning in nuclear fuel for fast reactors is a completely new product for the global nuclear industry. In itself, uranium-plutonium fuel makes it possible to expand the feed-stock base of the nuclear power industry, to recycle spent nuclear fuel instead of storing it and to reduce the volume of nuclear waste. Utilization of minor actinides is also an opportunity to significantly reduce radioactivity of the waste, which would make it possible in the future to abandon its complicated and expensive deep burial," he said.

The press service said Russia was currently the only country developing a complete Generation IV power system based on the closed nuclear fuel cycle technologies. In Seversk, West Siberia, Rosatom is building the Pilot Demonstration Energy Complex, including the power unit with the BREST-OD-300 fast reactor, the unit for nuclear fuel fabrication/refabrication, and the unit for irradiated fuel recycling.

Fast neutron reactors can be fueled not only by enriched uranium, but also secondary products of the nuclear fuel cycle, such as depleted uranium and plutonium extracted from spent nuclear fuel. The so-called afterburning of minor actinides in a fast reactor is the next step of the Russian nuclear industry in closing the nuclear fuel cycle. Under the influence of fast neutrons, they will be divided into elements that pose a much lower potential danger.

The Beloyarsk NPP went into service in April 1964. It generates around 16% of the Sverdlovsk region's electricity. The plant's first two units, light water graphite AMB-100 and AMB-200 reactors, have been permanently shut down. The third and fourth units are fast neutron BN-600 and BN-800 reactors, which were connected to the grid in 1980 and 2015, respectively.