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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
Frank Wols, Jan Leen Kloosterman, Danny Lathouwers, Tim Van Der Hagen
Nuclear Technology | Volume 186 | Number 1 | April 2014 | Pages 1-16
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-14
Articles are hosted by Taylor and Francis Online.
An inherently safe thorium-breeder pebble bed reactor has great potential to improve the safety and sustainability of nuclear energy. The aim of this work is to determine the conditions under which breeding is possible in a thorium-breeder pebble bed reactor (PBR) and to present possible core designs for such a reactor. A method is developed to calculate the equilibrium core configuration of a thorium-breeder PBR, consisting of a driver channel and a breed channel. The SCALE system is used for cross-section generation and fuel depletion, and a two-dimensional (r,z)-flux profile is obtained using the DALTON neutron diffusion code. With the code scheme, the influence of several geometrical, operational, and fuel management parameters on breeding capability can be studied. Four fuel reprocessing schemes are investigated. The first scheme recycles breeder pebbles into the driver channel after some delay for additional 233Pa decay. The second scheme reprocesses the discharged breeder pebbles to make driver pebbles with higher 233U content. The third scheme also reprocesses the uranium isotopes from the discharged driver pebbles. Criticality, and thus breeding, can only be achieved in practice for this case. The fourth scheme, which adjusts the driver pebble residence time to find a critical core, is used to design a thorium-breeder PBR under practical operating conditions. A breeder reactor can even be achieved for a 150-cm core diameter, the same as for the uranium-fueled HTR-PM, but the design presented operates at a significantly lower reactor power, 71 MW(thermal) compared with 250 MW(thermal).
