Tower Scanning as a Quantitative Tool

Tower scanning is well established in the process industries as a qualitative tool to help
troubleshoot separation towers. In this presentation it will be shown that through careful
and innovative application of gamma scanning and neutron backscatter techniques,
quantitative information about tray performance can be extracted. This will be illustrated
by comparing data taken under very controlled conditions on a hydrocarbon tower
equipped with windows, with the data obtained from scans of the tray downcomer and
active area. Three sets of trays designed to flood under jet flood, downcomer backup or
choke flood mechanisms were tested and studied. The experimental observations, tray
model predictions, and scan data for each of these sets of trays will be compared.
Based on this information it can be concluded that tower scanning can be used to
generate quantitative information about tray performance.