球床式高温气冷堆在线燃耗测量中<sup>239</sup>Pu的影响分析

球床式高温气冷堆在线燃耗测量中²³⁹Pu的影响分析

1. Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100086, China;
2. China Institute of Atomic Energy, Beijing, 102413, China

摘要: 高温气冷堆中,燃料的平均燃耗比较深。随着²³⁵U的消耗和²³⁹Pu的累积,²³⁹Pu的裂变就将成为一个不可忽略的部分。通过理论计算,讨论了²³⁹Pu的裂变对于燃耗测量的影响。计算表明,当燃料球燃耗达到80 000(MW.d)/t (U)时,²³⁹Pu的裂变所贡献的燃耗份额约26.7%,²³⁹Pu裂变产生的¹³⁷Cs和¹³⁴Cs分别占其各自总活度的27.2%和23.2%;比较而言,利用¹³⁷Cs活度来计算燃耗的方法比用活度比¹³⁴Cs/¹³⁷Cs好。
- 燃耗测量 /
- ²³⁹Pu /
- 燃料循环 /
- 高温气冷堆 /
- 裂变产物
Abstract: The portion of ²³⁹Pu in the nuclear fuel cycle of gas cooled high temperature reactor-pebble bed module（HTR-PM） is very important at the high level of burnup,which certainly influences the online burnup measurement.This problem was discussed in the paper.When the expected average burnup was 80 000（MW.d）/t（U）,the calculation result showed that the energy release from ²³⁹Pu fission contributed to the burnup of fuel pebble by 26.7% and the acitivity of ¹³⁷Cs and ¹³⁴Cs from ²³⁹Pu fission is about 27.2% and 23.2%,respectively.Further analysis also showed that it is better to determinate the burnup by the activity of ¹³⁷Cs in the pebble than by the activity ratio of ¹³⁴Cs/¹³⁷Cs.
- Burnup measurement /
- ²³⁹Pu /
- Fuel cycle /
- Hight temperature reactor /
- Fission product