环境大气氚的测定技术研究

Research on Measurement Technique of Tritium in Atmosphere

文章分析环境大气中氚的来源,并描述环境大气氚浓度测量系统的组成与测量原理。研究了累积氚取样装置中催化炉的催化温度和气体流速对催化效率的影响、冷阱冷却温度对氚回收率的影响,刻度了氚电解浓集装置的回收率,在此基础上测定了某核设施周围环境大气氚浓度。结果表明:在催化温度为350℃、催化效率为98%、电解浓集装置平均回收率为54%的实验条件下,本测试方法可高灵敏度地测定特定范围内外环境低水平大气氚浓度变化,探测下限可达0.1 Bq/m3。

The source of tritium in atmosphere was analyzed, and the composition and the principle of the system for measuring tritium concentration were described. The dependences of temperature of catalysis furnace, gas flowing rate on the catalysis efficiency and dependences of temperature of cooling trap on the tritium recovery ratio were studied. The tritium recovery ratio of the electrolyte enrichment device was calibrated, and the tritium concentration in atmosphere around a nuclear facility was measured. The results show that the concentration variation of low-level tritium in the outer atmosphere can be highly sensitively measured within a special range and the low limit of tritium detection is 0. 1 Bq/m^3 at the catalysis temperature of 350 ℃ and the catalysis efficiency of 98% as well as the average tritium recovery ratio of 54% of the electrolyte enrichment device.