Simultaneous application of X‐ray fluorescence and gamma spectrometer for analysis of radioactive waste material topic
26th Symposium of AER on VVER Reactor Physics and Reactor Safety (2016, Helsinki, Finland)
Intermediate storage of spent fuel decommissioning and radwaste / Spent fuel disposal and actinide transmutation
Abstract
SIMULTANEOUS APPLICATION OF X-RAY FLUORESCENCE AND GAMMA SPECTROMETER FOR ANALYSIS OF RADIOACTIVE WASTE MATERIALAnita Gerényi, Gábor Radócz, Imre SzalókiInstitute of Nuclear Techniques, Budapest University of Technology and Economics, 1111 Budapest, HungaryABSTRACTDetermination of the activity of the radioactive isotopes and concentration of inactive elementary composition in waste materials should be the basis of the identification for future management. For this purpose a new combined mobile X-ray fluorescence spectrometer (XRF) with silicon drift detector (SD) and gamma spectrometer using cadmium-zinc-telluride (CZT) detector was developed. The XRF analysis provides the chemical composition of the sample matrix. For calculation of the quantitative composition a new physical model based on the adaptation of the fundamental parameter method (FPM) was developed. For the numerical calculations new software was designed in MATLAB operation environment. This analytical method is capable of determination of the elementary composition of solid samples in range of 0.1-100% for elements in range of atomic number 12<Z<92. The XRF gamma spectrometers are mounted on vertically moving console of a commercial 3D printer. The sample is fixed on an x-y stage moving into horizontal directions. There is significant difference in the sensitive energy ranges of these two types of energy-dispersive semiconductor detectors (CZT and SDD); therefore it is possible to apply them simultaneously measuring the quantity of the major elements in the matrix and the activity of different isotopes. The XRF device has been constructed in confocal measuring arrangement, with approximately 2 mm of the focal spot diameter. Analytical capability, i.e. limit of detection, and lateral resolution of the confocal XRF spectrometer were determined. In order to evaluate and quantify the gamma spectra a new reverse Monte Carlo conception was designed and tested with application of the MCNP-6 validated code for simulation of gamma spectra recorded by a CZT detector having 1500 mm3 active volume.AcknowledgmentsThis work has been carried out in the frame of VKSZ-14-1-2015-0021 Hungarian project supported by the National Research, Development and Innovation Found.26th Symposium of AER on VVER Reactor Physics and Reactor Safety 55 10 – 14 October 2016, Helsinki, Finland