摘要
探讨了Purex流程中洗锝(TcS)工艺段的关键工艺参数,对其进行了优化,并用混合澄清槽台架进行了验证。结果表明:TcS工艺段最优工艺的确定,一方面要满足后续工艺段对Tc浓度的要求,同时须考虑后处理厂整体运行的经济性,以确定合理的Tc净化系数;TcS工艺段TcSW中HNO3浓度在4~4.5mol/L范围内,既能满足Tc净化系数最大,又能减少U、Pu的损失;根据确定的Tc净化系数,可确定1AP与TcSS1+TcSS2的最佳流比;在总酸量固定的条件下,TcSS1、TcSS2酸度和流比分配对Tc净化系数影响不大,较低的TcSS2酸度有利于降低TcSP的酸度,同时进入TcSW的U、Pu更少。
The primary technic parameters of technetium scrubbing(TcS)section were discussed.It can be concluded that the optimal technics of TcS section can not only meet the demand of the latter section of Purex process,such as U/Pu separation stage,but also accord the economy of the whole reprocessing plant.The optimization technics were validated through mixer-settler bench scale experiments.The results indicate that both the max decontamination coefficient of Tc and the least loss of U and Pu can be achieved when the concentration of nitric acid of TcSW in TcS section maintains 4-4.5mol/L.Based on the affirmatory decontamination coefficient of Tc,the optimal flow ratio of1 AP to TcSS1+TcSS2is determined.Changing the combination of HNO3 concentration and flow ratio can not remarkably improve the decontamination coefficient of Tc in TcS section if the overall consumption of HNO3 is fixed.The lower concentration of nitric acid of TcSS2 is benefit for the decrease of the nitric acid concentration of TcSP and thereduction of the loss of U and Pu.
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
2014年第S1期50-55,共6页
Atomic Energy Science and Technology
关键词
洗锝工艺段
工艺优化
净化系数
锝
后处理
technetium scrubbing section
technics optimization
decontamination coefficient
technetium
reprocessing
