裂片产物的赋存状态及其氧化挥发行为

Occurrence State and Oxidative Volatilization Behavior of Fragment Products

辐照后,燃料的化学组成和微观结构发生明显改变。裂变产物的存在形式分为四种:裂变气体、金属合金、单独存在的氧化物和以固溶体存在于燃料晶格中的氧化物,如Zr。与湿法后处理工艺相比,干法后处理工艺的高温首端工序裂片核素进入气相的比例较高。各裂片产物的赋存状态及其氧化挥发行为的明确,有利于指导后处理工艺的调整。

After irradiation, the chemical composition and microstructure of the nuclear fuel changed significantly. There are four forms of fission products: fission gases, metal alloy, individually present oxides and oxides existing in the fuel lattice as solid solutions. Compared with the wet process, the dry process has a higher proportion of fragment nuclides entering the gas phase in the high-temperature first end process. The determination of the occurrence state and the oxidation volatilization behavior of fragment products is beneficial to the adjustment of post-treatment process.