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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
Elsa Merle-Lucotte, Ludovic Mathieu, Daniel Heuer, Véronique Ghetta, Roger Brissot, Christian Le Brun, Eric Liatard
Nuclear Technology | Volume 163 | Number 3 | September 2008 | Pages 358-365
Technical Paper | Molten Salt Chemistry and Technology | doi.org/10.13182/NT08-A3994
Articles are hosted by Taylor and Francis Online.
Molten salt reactors (MSRs) are one of the six systems retained by Generation IV as a candidate for the next generation of nuclear reactors. The MSR is a very attractive concept especially for the thorium fuel cycle, which allows nuclear energy production with a very low production of radiotoxic minor actinides, so it has been selected by the Generation-IV International Forum. Its main characteristic is a strong coupling between neutronics and salt processing. Such nuclear reactors use a liquid fuel that is also the coolant. Elements produced during the reactor's operation, like fission products or transuranic elements, modify the neutronic balance of the reactor by capturing neutrons. As the fuel is liquid, partial processing of a limited amount taken from circulating salt is possible, in order to remove the poisoning elements, without stopping reactor operation. In this paper, we present a configuration that we consider to be a reference one for a thorium molten salt reactor (TMSR), and we study the influence of efficacy of different types of processing on the neutronic behavior of this reactor. By considering both the possibilities in chemistry and the neutronic effects, our aim is to work out an efficient, reliable, and realistic processing scheme.The processing includes in fact two components: an in-line bubbling system within the reactor that extracts the gaseous and metallic fission products quickly and a slower external processing unit that extracts the other fission products. A salt volume equal to the core volume is thus cleaned in several months. We have studied the influence of different processing rates on the reactor's behavior. This mainly affects the breeding ratio.Properties of the salt are also crucial. We choose in our simulations of the TMSR a 78 mol% LiF-22 mol% [heavy nuclei (HN)] F4 salt for the fuel, but lower HN proportions in the fuel salt are also examined in order to minimize the 233U inventory in the reactor. The neutron spectrum is largely modified by the HN proportion and has a deep impact on the reactor behavior. Our simulations evaluate the degradation of the breeding ratio from >1 for the reference configuration down to 0.86 due to a decrease of the HN proportion in the fuel salt.We conclude that the simplification of the salt processing that is addressed in this work improves the feasibility of the TMSR system.
