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DOE awards $2.7B for HALEU and LEU enrichment
Yesterday, the Department of Energy announced that three enrichment services companies have been awarded task orders worth $900 million each. Those task orders were given to American Centrifuge Operating (a Centrus Energy subsidiary) and General Matter, both of which will develop domestic HALEU enrichment capacity, along with Orano Federal Services, which will build domestic LEU enrichment capacity.
The DOE also announced that it has awarded Global Laser Enrichment an additional $28 million to continue advancing next generation enrichment technology.
Basar Sarer, Sümer Sahin, Mehtap Günay, Yurdunaz Çelik
Fusion Science and Technology | Volume 61 | Number 1 | January 2012 | Pages 302-307
Modeling and Simulations | Proceedings of the Fifteenth International Conference on Emerging Nuclear Energy Systems | doi.org/10.13182/FST12-A13437
Articles are hosted by Taylor and Francis Online.
The MCNPX code offers options based on physics packages; the Bertini, ISABEL, INCL4 intra-nuclear models, and Dresner, ABLA evaporation-fission models and CEM2k cascade-exciton model. The study analyzes the main quantities determining ADS performance, such as neutron yield, neutron leakage spectra, and neutron and proton spectrain the target andin the beam window calculated by the MCNPX-2.5.0 Monte Carlo transport code, which is a combination of LAHET and MCNP codes. The results obtained by simulating different models, cited above and implemented in MCNPX are compared with each other.The investigated system is composed of a natural lead cylindrical target and stainless steel (HT9) beam window. Target has been optimized to produce maximum number of neutrons with a radius of 20 cm and 70 cm of height. Target is bombarded with a high intensity linear accelerator by a 1 GeV, 1 mA proton beam. The protons are assumed uniformly distributed across the beam of radius 3 cm, and entering the target through a hole of 5.3 cm radius. The proton beam has an outer radius of 5.3 cm and an inner radius 5.0 cm. The maximum of the neutron flux in the target is observed on the axis ~ 10 cm below the beam window, where the maximum difference between 7 different models is ~ 15 %. The total neutron leakage out of the of the target calculated with the Bertini/ABLA is 1.83×1017 n/s, and is about 14 % higher than the value calculated by the INCL4/Dresner (1.60×1017 n/s). Bertini/ABLA calculates top, bottom and side neutron leakage fractions as 20 %, 2.3 %, 77.6 % of the total leakage, respectively, whereas, they become 18.6 %, 2.3 %, 79.4 % with INCL4/Dresner combination.