Speaker
Dr
Galina Lujaniene
(Institute of Physics)
Description
Radioanalytical method for the determination of radionuclides so called “difficult to determine” has been developed to characterize liquid and solid operational low and intermediate level radioactive waste. The main steps of the method involve digestion of sample of various matrixes, primary separation of radionuclides from matrix with the aim to reduce high γ activities and final purification of radionuclides using extraction chromatography. The commercially available Eichrom resins (UTEVA, TEVA, TRU, Sr Resin and Ni Resin) have been applied. The method enables the simultaneous determination of 238Pu, 239,240Pu, 241Pu, 241Am, 242Cm, 243,244Cm, 90Sr, 55Fe and 63Ni from a single sample. Radionuclides were measured by means of α spectrometry and liquid scintillation. After measurements of 238Pu and 239,240Pu, plutonium isotopes were removed from the stain steel disc and following additional purification 241Pu was measured using liquid scintillation. The method was applied for determination of radionuclides in samples of different matrixes derived from Ignalina NPP e.g. reactor water, spent fuel pool water, evaporated concentrate, spent resins, dust, graphite etc. Accuracy and precision of Pu, Am and Cm analysis were tested in intercomparison runs organized by the Risø National Laboratory, Denmark and in proficiency test organized by National Physical Laboratory, UK.
The authors would like to acknowledge the financial support of European Commission (European Atomic Energy Community [EURATOM]) for funding project 211333 in the Seventh Framework programme.
The work has also been supported by Agency for International Science and Technology Development Programmes in Lithuania (contract No. 31V-180).
Primary author
Dr
Galina Lujaniene
(Institute of Physics)
Co-author
Dr
Grigorijus Duškesas
(Institute of Physics)
