On-line detection of key radionuclides for fuel-rod failure in a pressurized water reactor. (August 2016)

• Record Type: Journal Article
• Authors: Qin, Guoxiu; Chen, Xilin; Guo, Xiaoqing; Ni, Ning
• Is Part Of: Applied radiation and isotopes. Volume 114(2016:Aug.)
• Page Start: 71
• Page End: 75
• Publication Date: 2016-08
• Subjects: Fuel-rod failure -- On-line detection -- LaBr3(Ce) detector -- Fission products; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2016.05.017
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: For early on-line detection of fuel rod failure, the key radionuclides useful in monitoring must leak easily from failing rods. Yield, half-life, and mass share of fission products that enter the primary coolant also need to be considered in on-line analyses. From all the nuclides that enter the primary coolant during fuel-rod failure, 135 Xe and 88 Kr were ultimately chosen as crucial for on-line monitoring of fuel-rod failure. A monitoring system for fuel-rod failure detection for pressurized water reactor (PWR) based on the LaBr3 (Ce) detector was assembled and tested. The samples of coolant from the PWR were measured using the system as well as a HPGe γ-ray spectrometer. A comparison showed the method was feasible. Finally, the γ-ray spectra of primary coolant were measured under normal operations and during fuel-rod failure. The two peaks of 135 Xe (249.8 keV) and 88 Kr (2392.1 keV) were visible, confirming that the method is capable of monitoring fuel-rod failure on-line. Highlights: In this work, we introduce a method of on-line fuel rod failure detection using LaBr3 (Ce) detector. As there were many kinds of radionuclides in the primary coolant after the fuel rod failure and the resolution of LaBr3 (Ce) detector was not as good as HPGe detector, so it need to select the radionuclides to be monitored in the measurement of fuel rod failure in order to provide reliable and accurate results. Nuclides which enter the primary coolant when fuel rod failed was analyzed, and then 135 Xe and 88 Kr were eventually chosen as the key radionuclides for on-line monitoring of fuel rod failure. The key radionuclides ( 135 Xe and 88 Kr) selected for on-line detection of fuel rod failure of PWR has the advantages of being less vulnerable to interference factors and high confidence.