TRU-SCAN and TRU-CAT Scanning of a Structured Packing Operating at DEEP Vacuum

Pioneering gamma scanning was conducted on a high capacity structured packing operating under deep vacuum during proprietary testing at FRI  The packing and multistage trough liquid distributor were tested with the para-/ortho- xylene system at 100 mbar in FRI’s 1.22 m diameter Low Pressure column.   From top to bottom, the column was baseline scanned when dry and followed by scanning at 24, 30, 67, 100 and 105 % of the packing’s Maximum Useful Capacity.  Distributor liquid levels derived from the scan data compared very well against liquid level data from FRI bubblers.  CAT-scans were performed at two different column elevations.  At each elevation, 81 data points through the bed of packing were recorded using 9 scanning source positions with 9 different detector positions for each source position around the column circumference.  Processing of the CAT-scan data using a proprietary mathematical technique provided significant insights regarding liquid holdup and liquid flow patterns in columns containing structured packings.