The test was video recorded through the view window above the tray 2 deck. The video presentation
titled "Sulzer Chemtech MVGT Tray Test" includes this recording as well as the installation footage. A
copy of this videotape is available to the membership on request.
EXPERIMENTAL PROCEDURE
A process flow diagram of the F.R.I. high pressure distillation unit as configured for these tests is
presented in
Figure 3. The tests were performed with the iC4/nC4 system at 100 and 165 psia (6.9 and
11.4 bar).
The standard F.R.I. operating procedure is to establish the flood point, decrease operating loads to about
20 per cent of flood to unload the trays, and then run a total reflux efficiency series. A procedure similar
to this was followed for most of the data taken. In addition to total reflux runs, five flood runs, two for
100 psia (6.9 bar) and three for 165 psia (11.4 bar), at L/V>1 (simulation of a stripping section) were
conducted. Flood runs at L/V < 1 (simulation of a rectifying section) could not be performed due to the
F.R.I. equipment limitation. A description of the data acquisition and data logging procedure is given in
the Progress Report for March-April 1997
(5)
.
RESULTS
Summary of Test Runs
Test results of the MVGT tray are presented in
Tables 2 to 4. The liquid composition data are listed in
Table 5. The typical process density and liquid volume fraction measured by gamma ray scanning are
given in
Table 6. A summary of the run conditions is listed as follows:
Pressure
Run No.
System
psia (bar)
Run Type
Table
20799-20819
iC4/nC4
100 (6.9 bar)
TR
2
20822, 20825
iC4/nC4
100 (6.9 bar)
LV
4
20823, 20824
iC4/nC4
165 (11.4 bar)
TR
3
20826-20845
iC4/nC4
165 (11.4 bar)
TR
3
20846-20848
iC4/nC4
165 (11.4 bar)
LV
4
The performance of the MVGT tray was compared with the F.R.I. type 2 valve tray and sieve tray tested
in 1987. The sieve tray had 0.5 in (12.6 mm) holes, a hole area of 10.6 percent of the bubbling area with
a downcomer area of 18.9% at top and 8.8% at the bottom, both based on the column cross sectional area.
Since the bubbling areas are not the same for all three devices, the comparison was also made based on
the superficial area capacity factor, C
s
, in addition to the bubbling area capacity factor, C
b,
when
applicable. A summary of the tray geometries is as follows:
Bubbling Area
DC Top
DC Bottom
Tray Type
ft
2
(m
2
)
ft
2
(m
2
)
ft
2
(m
2
)
MVGT
8.93 (0.83)
2.17 (0.20)
1.25 (0.12)
Type 2
9.25 (0.86)
1.59 (0.15)
1.59 (0.15)
Sieve
8.85 (0.82)
2.38 (0.22)
1.11 (0.10)
