Transcript PowerPoint Template - Universitas Brawijaya

14/15 Fall semester
Petroleum and Gas
Processing(TKK-2136)
Instructor: Rama Oktavian
Email: [email protected]
Office Hr.: M.13-15, Tu. 13-15, W. 13-15, Th. 13-15, F. 09-11
Outlines
1. Crude distillation unit: Desalter
2. Distillation column configuration
3. CDU material balance
4. Crude oil products uses
Crude Distillation Unit (CDU)
Crude Distillation Unit (CDU)
Crude Distillation Unit (CDU)
Crude Distillation Unit
Crude desalter unit
Salt content crude oil is usually denoted
as pounds salt (measured as NaCl) per
thousand barrels of crude oil (ptb)
Crude Distillation Unit
Crude desalter unit
Crude Distillation Unit
Crude desalter unit
The salt content should be lowered to between 5.7 and 14.3
kg/1000 m3 (2 and 5 PTB)
Poor desalting has the following effects:
1. Salts deposit inside the tubes of furnaces and on the tube
bundles of heat exchangers creating fouling, thus reducing
the heat transfer efficiency
2. Corrosion of overhead equipment
3. The salts carried with the products act as catalyst poisons
in catalytic cracking units
Crude Distillation Unit
Crude desalter unit operation variable
1. Desalting temperature – affect settling rate, typical desalting
temperature can vary between 50 and150 C (122 and 302 F)
2. Washing water ratio – affect in salt removal, Kuwait crude (31.2 API)
requires 7–8 vol% water addition relative to the crude rate
3. Water level - Raising the water level reduces the settling time for the
water droplets in the crude oil, thus improving the desalting efficiency
4. Washing water injection point
5. Demulsifier injection rate
6. Type of washing water - relatively soft to prevent scaling, slightly acidic
with a pH in the range of 6, free from hydrogen sulphide and ammonia
7. Pressure drop in the mixing valve - A pressure drop between 0.5 and
1.5 bar (7.4 and 22 psi) is used
Crude Distillation Unit
Crude electrostatic desalting unit
Crude Distillation Unit
Atmospheric distillation unit
Crude oil from the desalter is heated in a train of heat exchangers up to a
temperature of 250°C–260°C and further by a tube-still heater (also known as a
pipe-still furnace) to a temperature of 350°C–360°C
Top pressure is maintained at 1.2–1.5 atm
Vapours from the top of the column, consisting of hydrocarbon gases and
naphtha, emerge at a temperature of 120°C–130°C
A few plates below the top plate, the kerosene fraction is drawn at a draw
temperature of 190°C–200°C
A few plates below the kerosene draw plate, the diesel fraction ) is drawn at a
temperature of 280°C–300°C
The temperature of the stream at the bottom reaches around 340°C–350°C
Crude Distillation Unit
Atmospheric distillation unit
A typical atmospheric distillation column contains 41 plates
The hot feed crude oil is flashed in the fifth plate
Products:
- top distillate (IBP–140°C cut)
- straight run kerosene (140°C–270°C cut)
- straight run diesel (270°C–340°C cut)
- JBO (340°C–365°C cut)
- the bottom residue (RCO, 365°C +cut)
Crude Distillation Unit
Atmospheric distillation unit
Crude Distillation Unit
Atmospheric distillation unit
Crude Distillation Unit
Product stabilization
Crude Distillation Unit
Condition parameter
Column Pressure
Controlled by the back pressure of the overhead reflux drum
The top tray pressure is 0.4–0.7 bar gauge (6–10 psig) higher than the reflux
drum
The flash zone pressure is usually 0.34–0.54 bar (5–8 psi) higher than the top
tray
Overhead Temperature
must be controlled to be 14–17 C (25–31 F) higher than the dew point
temperature for the water to prevent water liquid condensation
Crude Distillation Unit
Condition parameter
Crude Distillation Unit
Crude material balance
Crude Assay Data
Crude Distillation Unit
Crude material balance
PROPERTIES OF TBP CUTS
Crude Assay Data
Cuts
Yield
Yield
Den
15°C
S
RSH
RON
MON
Napht.
Aro.
LIGHT
°C
wt%
vol %
kg/m3
wt%
mg/kg
clear
clear
vol%
vol%
kPa
NAPHTHA
15-65
3.52
4.52
644
0.0032
0
86.2
81.5
4.6
0.1
185.28
15-80
5.29
6.62
0.0037
1
86.1
81.2
9.9
0.3
150.93
Cuts
Yield
Yield
661
Den
15°C
S
RSH
Napht.
Aro.
HEAVY
°C
wt%
vol %
kg/m3
wt%
mg/kg
vol%
vol%
NAPHTHA
80-150
16.41
18.03
752
0.0081
2
32.2
11.3
80-175
22.45
24.29
764
0.0103
2
32.0
13.3
100-150
12.35
13.38
0.0090
2
32.9
14.5
Cuts
Yield
Yield
763
Den
15°C
S
RSH
Smoke
KEROSENE
GASOIL
Cetane Freez. Pt
RVP
°C
wt%
vol %
kg/m3
wt%
mg/kg
Pt mm
Acidity
mgKOH/
g
Index
°C
vol%
50°C
Point
150-230
21.72
22.08
813
0.029
2
16
0.08
35.6
-54
16.2
1.0
-
175-230
15.68
15.82
820
0.033
2
16
0.09
36.9
-50
15.1
1.2
-
150-250
27.87
28.16
0.034
2
16
0.09
37.9
-49
16.2
1.2
-
Cuts
Yield
Yield
818
Den
15°C
S
Anilin
CFPP
Pour Pt
°C
wt%
vol %
kg/m3
wt%
Point °C
Index
C
C
C
50°C
100°C
175-400
55.55
53.75
854
0.072
64
45.3
-6
-9
-12
2.5
1.2
11.7
-
230-400
39.86
37.93
869
0.088
68
48.1
-1
-1
-2
3.6
1.5
11.7
-
230-375
34.31
32.90
0.083
67
48.4
-7
-7
-8
3.1
1.4
11.7
-
UOPK
Asp C7
Cetane Cloud Pt
Aro.
Visc cSt
Flash
Visc cSt Visc cSt
UOPK
Flash
Point
Cuts
Yield
Yield
862
Den
15°C
S
Conrad.
Anilin
Ni
Va
Total N
Bas N
Pour Pt
VACUUM
°C
wt%
vol %
kg/m3
wt%
wt%
Point °C
mg/kg
mg/kg
wt%
mg/kg
C
100°C
150°C
DISTILLATE
375-550
17.84
15.73
937
0.15
0.5
80
0
0
0.027
102
41
6.1
2.5
11.6
0.1
375-565
18.53
16.31
939
0.15
0.8
80
0
0
0.031
110
41
6.6
2.7
11.6
0.1
375-580
19.09
16.77
941
0.16
1.2
80
0
0
0.041
117
42
7.0
2.8
11.6
0.2
400-580
13.54
11.74
0.18
1.7
81
0
1
0.052
152
47
10.1
3.7
11.6
0.2
Cuts
Yield
Yield
953
Den
15°C
S
Conrad.
Ni
Va
Total N
Pene
Asp C7
RESIDUE
Pour Pt
Visc cSt Visc cSt
°C
wt%
vol %
kg/m3
wt%
wt%
Acidity
mgKOH/
g
mg/kg
mg/kg
wt%
C
100°C
150°C
mm/10
wt%
> 375
20.77
18.11
948
0.17
4.2
0.3
1
2
0.179
34
9
3
587000
0.4
> 550
2.93
2.38
1020
0.32
26.5
0.4
5
15
1.100
48
869
74
199
2.0
> 565
2.24
1.80
1028
0.34
31.8
0.4
6
19
1.400
51
2470
145
124
2.4
> 580
1.68
1.34
1036
0.36
37.6
0.4
8
23
1.750
55
8420
321
91
This crude oil data sheet is for information purposes only. No guaranty is given as to its accuracy or as to any consequences arising from its use.
Visc cSt Visc cSt
wt %
TOTAL DTS / AM
2.7
Mar-14
Crude Distillation Unit
Material balance
Crude Distillation Unit
Solution
Step 1: Construct fifth order polynomial fit of TBP data versus vol%
Crude Distillation Unit
Solution
Step 2: From the end point of each cut, calculate the cumulative volume percent,
example: the cumulative volume percent for the off gas and the light straight run
naphtha is 1.33 and 8.6%, respectively
Crude Distillation Unit
Solution
Step 3: Calculating average normal boiling point. The average normal boiling
point for each cut is calculated at the mid percent of each cut.
in this case the light straight run naphtha is
1.33 + 7.27/2 or 4.965%
Average boiling point - to be 43.6 C
Crude Distillation Unit
Solution
Step 4: Calculating Molecular weight.
Crude Distillation Unit
Solution
Step 5: Calculating specific gravity.
Crude Distillation Unit
Solution
Crude Distillation Unit
Material balance
Vacuum Distillation Unit
Products
Light vacuum gas oil (LVGO)
Medium vacuum gas oil (MVGO)
Heavy vacuum gas oil (HVGO)
Vacuum residue
Vacuum Distillation Unit
Process overview