Abstract Burnup characteristics of americium burning U-free inert matrix PuO2+ZrO2 (ROX), and PuO2+ThO2 (TOX) with reactor- and weapons-grade plutonium fueled LWR cell are analyzed in comparison with a conventional UO2 and MOX fueled LWR cells. In these fuels, 212–1062 kg/GWe of AmO2 are added to optimize an adequate amount for an effective burning of Am and Pu as well. It is found that a small amount of AmO2 act as a burnable poison in UO2 fuel to decrease the excess reactivity at BOL. Thermal neutron spectrum of ROX + AmO2 fuel is softer than the other fuels due to the lack of secondary source of fissile material, which accelerate the fission reaction rates of 242MAm, 242GAm, 243Am and capture reaction rates of 241Am, 243Am. As a result, the effective burning of Am and Pu isotopes especially 241Am and 239Pu are great in amount in ROX + AmO2 fuel even though the production of 242Cm, 244Cm, 238Pu from Am are nearly same in these fuels. In ROX + AmO2 fuel, the production of long-lived fission products (LLFPs) and 237Np are little. By analyzing the quality of spent fuels and safety characteristics, 650–750 kg/GWe of Am are proposed for ROX fuel for once through burning.

中文翻译：

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镅燃烧无 U 惰性基质燃料的中子分析

摘要 与传统的 UO2 和 MOX 燃料 LWR 电池相比，分析了使用反应堆级和武器级钚燃料 LWR 电池的镅燃烧无 U 惰性基质 PuO2+ZrO2 (ROX) 和 PuO2+ThO2 (TOX) 的燃耗特性。在这些燃料中，添加了 212–1062 kg/GWe 的 AmO2 以优化足够的量，以有效燃烧 Am 和 Pu。发现少量 AmO2 作为 UO2 燃料中的可燃毒物以降低 BOL 的过度反应性。ROX+AmO2燃料的热中子谱由于缺乏裂变材料的二次源而比其他燃料软，加快了242MAm、242GAm、243Am的裂变反应速率和241Am、243Am的俘获反应速率。因此，尽管在这些燃料中从 Am 产生 242Cm、244Cm、238Pu 的产量几乎相同，但 Am 和 Pu 同位素特别是 241Am 和 239Pu 在 ROX + AmO2 燃料中的有效燃烧量很大。在 ROX + AmO2 燃料中，长寿命裂变产物 (LLFPs) 和 237Np 的产生很少。通过分析乏燃料的质量和安全特性，建议将 650-750 kg/GWe 的 Am 用于 ROX 燃料一次燃烧。