含MOX燃料堆芯衰变热及裂变产物积存量的特性研究

Characteristics Study for Decay Heat and Fission Product Inventory of Reactor Core with MOX Fuel

我国尚无MOX燃料的工程经验,需开展大量的论证工作。以国内M310型堆芯为对象,对使用30%MOX燃料的堆芯燃料管理方案进行分析,比较含MOX燃料堆芯和全UO2堆芯的衰变热、乏燃料水池热负荷和堆芯裂变产物积存量的特性差异。结果表明,堆芯衰变热、乏燃料水池热负荷变化较小,都不会超过原来的15%,堆芯裂变产物积存量中少量核素偏差较大,135Xe、136Cs等超过40%,其余核素变化较小。研究表明,含MOX燃料堆芯的辐射特性存在一定差异,但变化非常有限,不会对电厂的运行和安全产生影响。

The MOX fuel has a good future for widely application. Today, the MOX fuel technology has been developed and applied in many PWRs all over the world. But there is still no experience in China and a lot of analysis works are needed. In this paper, the decay heat of the reactor core, heat load of spent fuel pool and.fission product inventories of the reactor core according to the fuel management of M310 NPP with one third of the core filled with MOX fuel asserhblies are studied. Comparing the reactor core with MOX assemblies with the reactor core with UO2 assemblies, it shows that the changes of the decay heat of the reactor core, heat load of spent fuel pool are small, and they would not be 15% greater than UO2 fuel. The change of fission product inventories is also not large except some fission product nuclides as 135Xe and 136Cs, which are over 40% more than UO2 fuel. The result of this study proves that the radiation characteristics of MOX fuel core changes small, and has negligible impact on the plant safety and operation.