基于固体聚合物膜电解槽的新型水中氚电解浓集仪研制

Development of a new SPE electrolytic enrichment instrument for tritium in water samples

目前环境中大部分水体氚(3H)活度浓度水平已低于常用的液体闪烁测量方法的探测限,为准确测量氚的活度浓度,需要对样品中的氚进行浓集。广东省环境辐射监测中心通过分析氚在电解浓集过程中的影响因素,在关键部件的设计与研究基础上,研制出一款基于固体聚合物膜(Solid Polymer Electrolyte,SPE)电解槽的新型水中氚电解浓集仪,并对其综合性能进行了一系列测试实验,700 mL的水样经过浓集后测量,氚的探测限可降至0.09 Bq?L-1,比浓集前降低了10倍以上,提高了低水平氚的测量能力。该浓集仪可用于环保、地质水文、海洋、卫生、核电等领域。

[Background] The 3H activity concentration of most water samples in environment is lower than the detection limit of commonly used liquid scintillation measurement method. In order to measure the 3H activity concentration accurately, we need to enrich tritium from water sample.[Purpose] This study aims to develop an electrolytic enrichment instrument to meet the needs of daily environmental tritium analysis work.[Methods] First of all, influence factors of tritium in electrolytic concentration process were analyzed, then a new solid polymer electrolyte (SPE) electrolytic enrichment instrument was developed on the basis of the research and design of key components at Guangdong environmental radiation monitoring center (GERC). Finally, a series of experiments have been carried out on its comprehensive performance and the patent of the instrument has been obtained by GERC.[Results] After electrolytic enrichment, the detection limit of tritium in 700 mL water sample can be reduced to 0.09 Bq·L^-1, more than 10 times lower than that before enrichment, hence greatly improves the tritium detection capability.[Conclusion] This instrument has features of stable performance, long life, good safety, high electrolytic efficiency, high enrichment multiple, accurate control and good experience, it can be used in environmental protection, geology, hydrology, ocean, health, nuclear power and other fields.