|
|
RVP
Control FCCU Debutanizer
This table shows actual plant survey data from
an FCCU Debutanizer, compared with design and simulation data.
Based on this data, Ascent was able to determine
equipment fouling was a major contributor to the
bottom's RVP issues:
FCCU Debutanizer
Data
| |
|
|
|
|
Plant |
|
|
|
| |
Design |
|
Survey |
Simulation |
| |
|
|
|
|
| FCCU charge, MBPSD |
25 |
|
30.5 |
30.5 |
| Debutanizer charge, MBPSD |
31.1 |
|
29.5 |
29.5 |
| Debutanizer reflux, MBPSD |
14.6 |
|
11.2 |
11.0 |
| Debutanizer OH prod, MBPSD |
9.5 |
|
7.7 |
7.7 |
| Debutanizer OH pressure, psig |
165 |
|
155 |
155 |
| |
|
|
|
|
| Overhead C5+ purity, LV% |
0.5 |
|
1.7 |
1.7 |
| Bottom C4- purity, LV% |
0.05 |
|
0.7 |
0.7 |
| Bottom RVP |
|
|
7.0 |
7.7 |
| Bottom API gravity |
|
|
58.5 |
58.3 |
| |
|
|
|
|
| Estimated flooding percentage |
77 |
|
57 |
57 |
| |
|
|
|
|
| Condenser inlet temp, ° F |
148 |
|
146 |
152 |
| Condenser outlet temp, ° F |
100 |
|
111 |
113 |
| Amount of subcooling, ° F |
19 |
|
8 |
8 |
| Cooling water supply temp, °
F |
80 |
|
65 |
65 |
| Cooling water return temp, °
F |
105 |
|
102 |
102 |
| Condenser D Q,
MMBTU/hr |
29.1 |
|
23.8 |
23.8 |
| LMTDc, ° F |
36.5 |
|
50.8 |
50.8 |
| Overall heat transfer coef., U |
124 |
(1) |
44.3 |
44.3 |
| Cooling water flow rate, gpm |
2,292 |
|
1,279 |
1,279 |
| Cooling water D P,
psi |
8 |
|
22 |
3
|
| |
| (1) The unit
was over-surfaced so that the U required was only
76.3. |
| |