Laser based technique for monitoring heavy water leaks in nuclear reactors: performance validation with conventional techniques

Abstract

In a pressurized heavy water reactor (PHWR), monitoring leakages of heavy water from coolant and moderator systems is very important for reactor safety as well as health of operating personnel. In view of this, heavy water leak monitoring system based on off-axis integrated cavity output spectroscopy (OA-ICOS) technique is developed. The developed system estimates the amount of heavy water in the samples by measuring the HDO concentration with the detection sensitivity of ±1.2 ppm. The performance of this system is studied by measuring various samples obtained from the Dhruva research reactor at Bhabha Atomic Research Centre. The validation of the data obtained using this system is carried out using tritium activity measurements of same samples. The results are also compared with D/H ratio measurements obtained by isotope ratio mass spectrometer (IRMS) . The measured HDO concentration of various samples using the developed system shows a good correlation with the measurements using IRMS and tritium activity measurement techniques.