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Antares achieves zero-power criticality at INL
Leveraging more than $140 million in private capital fundraising, over 322,000 square feet of operational manufacturing space, and multifaceted partnerships with the Departments of Energy and Defense, reactor start-up Antares has become the first company involved in the Reactor Pilot Program to achieve zero-power fueled criticality—a full month ahead of the July 4 deadline set by President Trump’s Executive Order 14301.
This milestone, announced yesterday, was achieved with the company’s Mark-0: a sodium heat-pipe-cooled, TRISO-fueled microreactor. The Mark-0 is a forerunner to the company’s flagship design, which it calls the R1. For Antares, this development represents a key validation of its reactor physics, control systems, and supply chain.
J. E. Klein
Fusion Science and Technology | Volume 67 | Number 2 | March 2015 | Pages 416-419
Proceedings of TRITIUM 2013 | doi.org/10.13182/FST14-T42
Articles are hosted by Taylor and Francis Online.
The reduction in hydride absorption rate due to ”blanketing” can be explained in terms of a reduced hydrogen partial pressure in the bed due to the accumulation of inerts (i.e. non-hydrogen isotopes) in the bed void volume. Literature results show reduced absorption rates when protium for bed absorption contains helium with low-end inert compositions in the 0.6 to 1% range. A hydride bed containing 9.66 kg of LaNi4.25Al0.75 (LANA0.75) metal hydride - a nominal capacity of 1400 STP-L, was cycled repeatedly to decrepitate the hydride material into smaller particles for bed strain measurement. The hydride cycles added and removed nominally 1000 to 1100 STP-L of protium per hydride cycle. Consistent and repeatable absorptions results were observed for different absorption cycles. During one of the absorption tests, slower absorption results were obtained due to the use of typical grade (500 ppm inerts), instead of research grade, protium which blanketed the bed. The impact of 0.05% inerts in protium on bed absorption rate is shown and explained in terms of an increase in inert partial pressure as the bed was loaded.