含氚气体中氚分压BIX在线测量方法研究  

On-line Measurement of Tritium Partial Pressure in Gas Containing Tritium by β-ray Induced X-ray

作　　者：郭一帆[1] 刘志珍[1] 吉晓梅[1] 郭星辰[1] 占勤[1] 赵崴巍[1] 杨洪广[1] 

机构地区：[1]中国原子能科学研究院反应堆工程研究设计所,北京102413

出　　处：《原子能科学技术》2016年第2期363-368,共6页Atomic Energy Science and Technology

基　　金：国家磁约束聚变能专项资助(2015GB109002)

摘　　要：建立了一种聚变堆氘氚燃料循环系统燃料气及工艺气等含氚混合气体中氚分压在线快速测量方法,该方法通过测量氚衰变产生的β射线与材料相互作用发射的轫致X射线(BIX),利用轫致X射线的计数率与含氚气体氚分压的标定关系曲线,实现含氚气体中氚分压(活度浓度)的实时测量。该方法中的轫致X射线是通过β射线与表面喷金的铍窗材料作用而产生的,X射线的测量采用NaI(Tl)探测器。研究过程中建立了轫致X射线计数率与氚分压的标定关系曲线,对于纯氚气体,氚压测量范围为1Pa^10kPa(氚活度浓度为10^(12)~10^(15) Bq/m^3)时,计数率(C)与氚压(p)的标定曲线为C=5.01×10~4(1-e^(-4.55×10^(-5)p)),其指数拟合相关系数为1.000 00。对于氚体积分数为1%的氚-氦混合气体,氚分压测量范围为1~100Pa(氚活度浓度为10^(11)~10^(14) Bq/m^3)时,计数率与氚分压的标定曲线为C=5.24×10~2(1-e^(-4.69×10^(-3)p)),其指数拟合相关系数为0.998 60。对于氚体积分数为1%的氚-氢混合气体,氚分压测量范围为1~100Pa(10^(11)~10^(14) Bq/m^3)时,计数率与氚分压的标定曲线为C=5.18×10~2(1-e^(-4.61×10^(-3)p)),其指数拟合相关系数为0.999 53。利用以上标定曲线,对任意氚分压的含氚混合气体进行验证测量,结果表明,该方法测量精度较高、响应速度快、测量稳定性好,在氚测量技术中是一种很有前景的方法。A promising method of on-line and real-time measurement for gas containing tritium in fuel processing systems of DT fusion facility was introduced. The principle of this method is observing the hremsstrahlung X-ray induced by the interaction between particles and material （BIX）. A correlation between the counting rate of bremsstrahlung X-ray and the tritium partial pressure can be presented, and it realizes the on-line and real-time monitoring of tritium partial pressure. The material used for generating bremsstrahlung X-rays is a beryllium window with evaporated golden film on it. The bremsstrahlung X-ray is monitored by a NaI（T1） scintillation counter. For the pure tritium, when the tritium partial pressure range is 1 Pa-10 kPa （1012-1015 Bq/m3）, the calibration curve of C-p is C= 5.01 × 104 （1-- e-4sa×10^-5P）. For the 1% atoms tritium mixture diluted with helium/hydrogen, when the tritium partial pressure range is 1 Pa- l00 Pa （1011-1014 Bq/m3）, calibration curves of C-p are C=5.24X 102 （1-e-4.69×1-3p） and C= 5.18× 102（1--e 4.61×10- 3p） respectively. The correlation coefficients of the three kinds of gases are 1. 000 00, 0. 998 60 and 0. 999 53 respectively. Based on the above calibration curves, the expressions in random tritium partial pressure were tested. The results show that this method is good at measuring accuracy, responding rate and stability. It is a promising method in tritium measuring technique.

关 键 词：氚测量 在线测量 氚分压 β射线诱发X射线 

分 类 号：TL271.7[核科学技术—核燃料循环与材料]