放射性废树脂特种水泥固化体的辐照稳定性  

Radiation stability of a cementation matrix for spent radioactive resin

作　　者：李俊峰[1] 邱瑜[1] 王建龙[1,2] 

机构地区：[1]清华大学核能与新能源技术研究院,先进核能技术协同创新中心,北京100084 [2]清华大学放射性废物处理北京市重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2017年第4期410-414,共5页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(20701024,21171104);国家重大专项基金资助项目(2013ZX06002001);国家“八六三”高技术项目(2012AA063504);清华大学自主科研项目(20121087949)

摘　　要：为了研究辐照对放射性废树脂特种水泥固化体的影响,确保树脂水泥固化体在长期处置过程中的稳定性,该文重点比较了树脂固化体经过不同剂量的γ射线辐照前后抗压强度和冻融实验后强度以及核素浸出率的变化规律,并通过扫描电镜比较了辐照前后固化体水化产物微观结构的变化情况。研究结果表明:辐照会使固化体抗压强度降低,损失幅度随剂量的增加而增大,并会加剧冻融实验引起的固化体强度损失程度;辐照后固化体对浸出离子的吸附能力降低;微观结构中,铝胶胶团含量相对减少,辐照可能引起其水化产物中高铝凝胶的分解,从而导致对核素滞留能力的降低和浸出率的升高;在累积辐照剂量小于10~5 Gy时,辐照不会对固化体稳定性产生严重影响。The radiation stability of the cementation matrix for spent radioactive resin when exposed to high radioactive fluxes was investigated using a sulfoaluminate cementation matrix for radioactive waste.The variation of the compressive strength after irradiation,the strength losses after freezing and the leach rate were compared for variousγ-ray radiation doses.The microstructures of the hydration products in the irradiated cementation matrix were observed using an SEM.The results show that the radiation reduces the compressive strength of the cementation matrix with the losses increasing with the dose.The strength losses after freezing were also increased by the radiation.The adsorption of leaching ions was reduced. The aluminium micelles in the microstructure were reduced. The radiation may cause the decomposition of the aluminium micelles,which may led to the increased radionuclide leach rate.The results also showed that the matrix stability was not affected by the radiation when the total absorbed dose was below 10~5 Gy.

关 键 词：放射性废树脂 水泥固化 辐照稳定性 抗压强度 浸出率 

分 类 号：X591[环境科学与工程—环境工程]