(0.83 m
2
). The percent open slot area for the tray was about 14.5% of the bubbling area. More details of
the tray provided by Sulzer Chemtech can be found in
Table 1.
Gamma Ray Scanning Equipment
The gamma ray scanning equipment was the same as that described in the Progress Report for May-June
1995
(4)
.
INSTALLATION OF EQUIPMENT
Figure 2 is the F.R.I. high pressure distillation column configuration for the MVGT tray test, locating the
trays, sampling locations, thermowells, pressure taps, bubblers, and auxiliary equipment in the column.
Eight MVGT trays were installed in the column. With the exception of the top tray, the tray spacing was
24 in (610 mm). The top tray was installed acting as a heat transfer and a liquid distributing tray. The
spacing between the top tray and tray below was 36 in (914 mm). The reflux was introduced to the top
tray using a 51 in (1295 mm ) long false downcomer. A basket of 2 inch (51 mm) Nutter Ring
TM
was
placed inside the false downcomer to uniformly distribute the reflux liquid. The deck of the first (bottom)
tray was placed 101 in (2565 mm) above the column bottom head seam. A baffle was attached to the first
tray downcomer to prevent the vapor from entering the downcomer. Three bubblers were used to
measure liquid head inside downcomers of trays 3, 5 and 7. The bubblers were made of 0.375 in (9.5
mm) copper tubing with a 45-degree slanted opening with a continuous nitrogen purge. The bubblers
were installed so that the openings were not facing the liquid flow. All three bubblers were installed in
the center of the downcomer bottom plates. Liquid samples were taken from each tray. For all the tray
liquid samplers, a 0.375 in (9.5 mm) brass bulkhead fitting was installed in the bottom plate of the
downcomer to withdraw the liquid samples from the downcomer, then a length of 0.375 in (9.5 mm)
diameter copper tubing was then used to direct the liquid samples to the column point. To measure
liquid temperatures, a thermowell was installed in the bottom plate of the downcomer close to the
sampling point. Samples and temperature measurements were also taken from the liquid streams of the
reflux, bottom and feed flows. Differential pressure drop transducers (DP cells) were used to measure
the pressure drops over Trays 1-8, the bottom section below Tray1 to above Tray 4, the top section below
Tray 5 to above Tray 8, and across Trays 7 and 8. As a standard procedure in F.R.I., all the DP cell legs
were continuously purged with a constant flow of nitrogen.
The installation and portions of the tests were observed and approved by Sulzer Chemtech
representatives.
Gamma Ray Scanning
The calibration and operation of the gamma ray scanning equipment was described in detail in the May-
June 1995
(4)
Progress Report. Two horizontal positions were scanned: Tray 4 centerline, and 20 in (508
mm) off centerline through the Tray 5 downcomer. For each horizontal position, the vertical scanning
position is listed in
Table 6. A bubbler was also installed in this downcomer to compare the backups by
both measurement methods.
Video Taping and Visual Observation
