Frazer-Nash to support IMSR graphite moderator fabrication

Thursday, 28 November 2019

UK- and Australia-based systems and engineering technology company Frazer-Nash has provided consulting services to the UK government and the operators of the country's current fleet of 14 advanced gas-cooled reactors (AGRs), which use graphite moderators. Terrestrial Energy said it would draw on this "world-leading graphite knowledge and nuclear engineering experience" as it proceeds with engineering programmes for deployment of the first IMSR plant. "Graphite moderator engineering for fabrication is a key element in our IMSR development programme," Terrestrial Energy CEO Simon Irish said.

The UK has operated graphite-moderated nuclear reactors - Magnox and AGRs - for electricity generation since 1956, during which extensive studies on the performance of reactor graphite have been counducted, the companies said.

Neil McDougall, Managing Director of Frazer-Nash, said the company would be leveraging its work with the UK-government initiated and funded Nuclear Innovation Programme in its work to support the fabrication of the IMSR moderator. "We look forward to contributing to Terrestrial Energy's game-changing IMSR power plant project and to its commercial deployment," he said.

Molten salt reactors (MSRs) use fuel dissolved in a molten fluoride or chloride salt, which functions as both the fuel (producing the heat) and the coolant (transporting the heat away and ultimately to the electricity generating equipment). Terrestrial's IMSR builds on 50 years of MSR experience at the USA's Oak Ridge National Laboratory, and integrates the primary reactor components, including the graphite moderator, into a sealed and replaceable reactor core unit with an operating lifetime of seven years. Irradiation studies on the behaviour of graphite under IMSR conditions are currently under way at the Petten high-flux reactor in the Netherlands as part of a test programme being carried out by Terrestrial Energy and NRG.