Unit Description
A. PURPOSE
The Vacuum Unit function
separates the reduced crude
fed from the crude units
into gas oils and vacuum
resid. This unit operates
at a vacuum and temperatures
that permit distillation
of the gas oils without
excessive cracking and cocking.
B. CAPACITY
Unit revamp 1982
Design Throughput 30,000
BPD
C. PROCESS DESCRIPTION
The
vacuum distillation process
involves heating the reduced
crude charge from the
Crude Unit to 730oF and
separating the gas oils
from the resid in the
vacuum column. The feed
temperature is obtained
by exchanging heat with
the heavy vacuum gas oil
and column bottom streams
and then passing the preheated
feed through fired heaters.
Vacuum is generated by
using two trains of three-stage
steam ejectors located
on the column overhead
vapor stream. Hydrocarbon
gases (from cracking in
the furnace and the flash
zone) and inert gases
(from leakage) are compressed
by the steam ejectors
and a compressor and are
sent to fuel.
The light vacuum gas oil
product is drawn off near
the top of the tower and
sent to the hydrocracker.
The heavy vacuum gas oil
product is withdrawn and
Sent to the FCC Feed Hydrotreater
Unit and then on to the
FCC Unit. Slop wax and
vacuum column bottoms
are sent to the Coker
Unit.
D. CHARGES AND YEILD
|
Products |
|
|
|
|
BPD |
%V. |
|
LVGO- FCC Feed |
11060 |
37.35 |
|
HVGO- FCC Feed |
11200 |
37.82 |
|
Asphal - No. 6 fuel
& asphalt
|
7350 |
24.83 |
|
Total |
29610 |
100.00 |
|
EQUIPMENT
LIST |
|
Heater |
H1R |
70 M BTU/Hr., 100 PSIG,
900 F |
|
Vacuum tower |
V1 |
20'ID x 74'-6"
T/T |
|
Sample/waste accum.
tank |
V2 |
2' ID x 8' T/T |
|
Excess water pot |
V4 |
2'-11" ID x 7'-10.5"
T/T, 150 psig |
|
KOT Pot |
V3 |
2'-5.5/8"X 9' T/T |
|
Heat Exchangers |
|
|
|
Vacuum Jets Coolers
|
E9ABC |
31' x 16', 6000 sft.
3 series |
|
LVGO/Raw Crude |
E15AB |
48" x 16', 8,090
sft, 2 series |
|
LVGO Coolers |
E11AB |
31" x 1', 3,562
sft., 2 series |
|
LVGO Cooler |
E5 |
47" x 16', 4,580
sft. |
|
HVGO/Flash Drum Crude
|
E14AB |
53" x 16', 9794
sft., 2 series |
|
Desalted Cr/North HVGO
|
E3AB |
37' x 16', 5640 sft.,
2 series +1 parallel |
|
Desalted Cr/South HVGO
|
E3CD |
37" x 16', 5640
sft., |
|
|
|
E4 33" x 16', 2240
sft., |
|
HVGO Pump Around cooler
|
E6 |
42" x 16', 3450
sft. |
|
Slop Wax Cooler |
E7 |
17" x 16', 486
sft. |
|
Aspha1t/Desalted crude
|
E1AB-R |
33" x 12', 3480
sft. |
|
Asphalt Cooler |
E8 |
10" x 16', 108
sft. |
|
Asphalt Cooler |
E13 |
29" x 16', 1660
sft. |
|
No.6 Oil Cooler |
E10 |
29" x 16', 1720
sft. |
Refineries |
All Plants
|
|
