NDA MEASUREMENT OF THE ENRICHMENT OF URANIUM IN THE PIPE FOR A GAS CENTRIFUGE ENRICHMENT PLANT.

A NDA instrument has been developed to determine the enrichment of gas phase uranium in pipes for a gas centrifuge enrichment plant. The enrichment of gas phase uranium could be measured by combining the passive gamma rays measurement with X-ray fluorescent analysis. The passive gamma rays measurement has extensively been performed in the last works. Successively the amount of deposited uranium has been measured for a long-term plant operations. Some increase of deposited uranium was observed. Determination of total mass of uranium in a pipe was studied by X-ray fluorescent analysis on a test loop system. It was found that total mass of gaseous UF in the pipe could be determined accurately enough in implementation of safeguards.