Russia’s BN-800 reactor at unit 4 of the Beloyarsk NPP, a sodium-cooled fast neutron reactor, completed 15-day integrated trials operating at 100% on 2 September. The trials confirmed ability of the power unit “to bear load steadily at the nominal power level as per design parameters without departures”, a plant statement said. It was the last stage of testing for the BN-800 equipment. Before it can be formally commissioned for commercial operation, regulator Rostechnadzor must carry out a final inspection to ensure compliance with design and issue a statement to that effect. Russian state nuclear corporation Rosatom will then publish a resolution permitting commercial operation. All these procedure are planned to take place during September. The 789MWe Beloyarsk 4 was first connected to the grid on 10 December 2015 and brought to the rated power for the first time in late May.

Progress was also reported on plans for another fast reactor, the lead-cooled BREST-OD-300, which is to be built at the Siberian Chemical Combine (SCC)

TsNIITMASH (part of the holding Atomenergomash) has won the tender for technological support of development and manufacture of components for the advanced reactor installation, Atomenergomash said on 1 September.

TsNIITMASH is the chief material science organization in the BREST-OD-3 project, which will be part of the Pilot Demonstration Power Complex (PDPC) at SCC.

The new contract is a continuation of R&D TsNIITMASH carried out earlier, on manufacture of semi-products, development of the welding technology and justification of design characteristics to assess strength and lifetime performance of the reactor. Under the new contract TsNIITMASH will “deliver the required information for computing engineers and designers. “BREST-OD-300 differs from previous generations of reactors, including its pre-set pressure and critical temperature parameters; therefore, it is necessary to produce a regulatory document and process procedures, which will regulate requirements for parts and design features of the new facility,” the statement explains. The welding, inspection and qualification provisions, as well as process procedures for some welds, will updated at the stage of the contract fulfillment.

Meanwhile, SCC has completed acceptance tests of dense mixed nitride uranium-plutonium fuel rods for advanced fast neutron reactors, the company said on 5 September. This set of fuel rods was fabricated as part of an integrated programme of calculation and experimental justification of the dense fuel. The rods will be used to make fuel assemblies with experimental fuel for the planned BN-1200 reactor (a larger version of the BN-800) and BREST.

The assemblies will be fabricated by SCC’s chemical metallurgical plant and will be accepted in September.

Following the necessary acceptance tests, the experimental assemblies will be installed for studies in the reactor core of the BN-600 at unit 3 of the Beloyarsk NPP. “The studies should verify their operating characteristics and justify performance of mixed nitride fuel in the BN-1200 and BREST-OD-300 reactors,” the statement said.