乏燃料后处理湿法工艺铀-钚混合共沉淀转化技术初步研究

A Survey about the Coprecipitation and Conversion of Mixed U-Pu Oxalates for Aqueous-based Reprocessing of Spent Nuclear Fuels

通过调查研究所收集的材料并进行分析探讨,本文分别从COEX工艺与PUREX工艺流程的对比、锕系元素草酸沉淀技术和扩展改进后的草酸共沉淀技术研究、锕系元素共沉淀晶体构造与沉淀产物的分解方法、以及COEX流程最终氧化产物的特性对MOX燃料元件制作产生的影响等方面较为系统的阐述了乏燃料后处理湿法工艺中“铀-钚混合共沉淀转化技术(COEX)”的技术特点。通过对比PUREX工艺的流程,并结合MOX燃料的制作工艺,本文从不同角度总结概括了COEX流程的工艺优势。最后,依据这些年收集到的COEX工艺工业化经验反馈,本文列举了多项目前该技术显现的工程难题。最终本文的结论为:与理想的实验室规模研究相比,COEX工艺工业化仍面临诸多问题和挑战。考虑到要实现更为先进的乏燃料后处理技术,具备稳妥可行的工程方案也是必不可少的条件,所以目前COEX工艺仍不具备成熟的工业化条件。

This paper respectively compared with PUREX processing technology,the coprecipitation and conversion of mixed actinide oxalates technology improvement,the influence of MOX fuel production,expounding systematically the technical characteristics,advantages and challenges of mixed uranium-plutonium coprecipitation and conversion for aqueous-based reprocessing of spent nuclear fuels(COEX).The main problems of this technology from laboratory scale to industrial scale are summarized with the aim of achieving a more advanced concept of spent fuel reprocessing.