Energy dispersive K x-ray fluorescence analysis for on-line process control of heavy metal concentrations

The analytical technique of energy dispersive x-ray flourescence analysis (XRFA) is studied in this paper. By using XRFA it is possible to measure nondestructively quantitative concentrations of heavy metals from process streams directly through industrial gauge pipes. The semiconductor detector, a high purity germanium detector (HPGe) housed in a sealed and evacuated cryostat is described. Two 5 to 10 millicurie radioactive Co-57 sources are used instead of an x-ray tube to stimulate x-ray emission. Analog electronics and analog to digital converter are also described. Some installations of XRFA at the Savannah River reprocessing plant and at the Allied General Nuclear Services plant are noted. Several reasons why the K x-ray flourescence analysis technique is innovative and practical for on-line or off-line near-real-time applications are summarized