Small modular reactors have garnered considerable attention in the recent years. Plate fuel elements exhibit a good application prospect in small modular pressurized water reactors for marine applications. Further, improved economic benefits can be achieved by extending the core lifetime of small modular reactors. However, it is necessary to realize a large initial residual reactivity for achieving a relatively long burnup depth finally. Thus, the selection of a suitable burnable poison (BP) is a crucial factor that should be considered in the design of small modular reactors. In this study, some candidate BPs are selected to realize the effective control of reactivity. The results show that ²³¹Pa₂O₃, ²⁴⁰Pu₂O₃, ¹⁶⁷Er₂O₃, PACS-J, and PACS-L are ideal candidates of BP, and since the characteristics of BP can increase the final burnup depth of assembly, the economic benefits are gained. Additionally, an optimal combination scheme of BPs is established. Specifically, it is proved that through a reasonable combination of BPs, a low reactivity fluctuation during the lifetime can be achieved, leading to a large final burnup depth.

近年来，小型模块化反应堆引起了相当大的关注。板式燃料元件在船用小型模块化压水堆中展现出良好的应用前景。此外，可以通过延长小型模块化反应堆的堆芯寿命来提高经济效益。然而，需要实现较大的初始剩余反应性才能最终实现相对较长的燃耗深度。因此，选择合适的可燃毒物 (BP) 是小型模块化反应堆设计中应考虑的关键因素。在本研究中，选择了一些候选BP，以实现对反应性的有效控制。结果表明，²³¹ Pa ₂ O ₃、²⁴⁰ Pu ₂O ₃、¹⁶⁷ Er ₂ O ₃、PACS-J和PACS-L是BP的理想候选者，由于BP的特性可以增加装配的最终燃耗深度，因此获得了经济效益。此外，还建立了BP的最优组合方案。具体而言，证明了通过合理的BPs组合，可以实现寿命期间的低反应性波动，从而导致较大的最终燃耗深度。