Calculate the EFV Curve of Whole Crude at Atmospheric Pressure
From the crude TBP curve, the slope of the whole curve is 11.8
F/%vol (10–70 %
vol on TBP temperatures divided by 60). From the Maxwell curves the slope of the
flash reference line is 8.5
F/%vol. (See the chapter “▶ Introduction to Crude Oil
and Petroleum Processing” in this Handbook.)
Table 2 Cut characteristics
Component
%vol on crude
SG at 60
F
Wt factor
Mol wt
Mol factor
Overheads cut from gas to 375
F TBP cut point (25 vol% on crude)
C2
0.11
0.374
0.411
30
0.014
C3
0.84
0.508
4.267
44
0.1
iC4
0.40
0.563
2.252
58
0.039
nC4
1.53
0.584
8.935
58
0.154
C5’s
3.02
0.629
18.996
72
0.264
C6
3.60
0.675
24.300
86
0.286
C7
4.50
0.721
32.445
100
0.324
Comp 1
3.50
0.743
26.005
114
0.228
2
3.77
0.765
28.841
126
0.229
3
2.41
0.776
18.702
136
0.138
4
1.32
0.788
10.402
152
0.068
Total
25.0
0.702
175.556
95.2
1.884
Kerosene cut range 375–480
F (10 %vol on crude)
2
4.0
0.765
30.6
126
0.24
3
14.0
0.776
108.64
136
0.80
4
22.0
0.788
173.36
152
1.14
5
24.0
0.799
191.76
165
1.16
6
21.0
0.810
170.10
177
0.96
7
13.0
0.825
107.25
190
0.56
8
2.0
0.839
16.78
205
0.08
Total
100.0
0.798
798.49
161.6
4.94
Light gas oil cut range 480–610
F (12 %vol on crude)
6
2.0
0.810
16.2
177
0.09
7
9.0
0.825
74.25
190
0.39
8
38.5
0.839
323.02
205
1.58
9
40.5
0.848
343.44
238
1.51
10
10.0
0.860
86.00
250
0.34
Total
100.0
0.843
842.91
215.6
3.91
Heavy gas oil cut range 610–680
F (7.0 %vol on crude)
9
6.0
0.848
50.88
228
0.22
10
33.0
0.860
283.80
250
1.14
11
61.0
0.887
540.77
287
1.88
Total
100.0
0.875
875.45
270.2
3.24
Atmospheric and Vacuum Crude Distillation Units in Petroleum Refineries
163
From the crude TBP curve, the slope of the whole curve is 11.8
F/%vol (10–70 %
vol on TBP temperatures divided by 60). From the Maxwell curves the slope of the
flash reference line is 8.5
F/%vol. (See the chapter “▶ Introduction to Crude Oil
and Petroleum Processing” in this Handbook.)
Table 2 Cut characteristics
Component
%vol on crude
SG at 60
F
Wt factor
Mol wt
Mol factor
Overheads cut from gas to 375
F TBP cut point (25 vol% on crude)
C2
0.11
0.374
0.411
30
0.014
C3
0.84
0.508
4.267
44
0.1
iC4
0.40
0.563
2.252
58
0.039
nC4
1.53
0.584
8.935
58
0.154
C5’s
3.02
0.629
18.996
72
0.264
C6
3.60
0.675
24.300
86
0.286
C7
4.50
0.721
32.445
100
0.324
Comp 1
3.50
0.743
26.005
114
0.228
2
3.77
0.765
28.841
126
0.229
3
2.41
0.776
18.702
136
0.138
4
1.32
0.788
10.402
152
0.068
Total
25.0
0.702
175.556
95.2
1.884
Kerosene cut range 375–480
F (10 %vol on crude)
2
4.0
0.765
30.6
126
0.24
3
14.0
0.776
108.64
136
0.80
4
22.0
0.788
173.36
152
1.14
5
24.0
0.799
191.76
165
1.16
6
21.0
0.810
170.10
177
0.96
7
13.0
0.825
107.25
190
0.56
8
2.0
0.839
16.78
205
0.08
Total
100.0
0.798
798.49
161.6
4.94
Light gas oil cut range 480–610
F (12 %vol on crude)
6
2.0
0.810
16.2
177
0.09
7
9.0
0.825
74.25
190
0.39
8
38.5
0.839
323.02
205
1.58
9
40.5
0.848
343.44
238
1.51
10
10.0
0.860
86.00
250
0.34
Total
100.0
0.843
842.91
215.6
3.91
Heavy gas oil cut range 610–680
F (7.0 %vol on crude)
9
6.0
0.848
50.88
228
0.22
10
33.0
0.860
283.80
250
1.14
11
61.0
0.887
540.77
287
1.88
Total
100.0
0.875
875.45
270.2
3.24
Atmospheric and Vacuum Crude Distillation Units in Petroleum Refineries
163