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3.1.8. Kiến thức bổ sung Edmister method: ASTM-TBP

 TBP temperature difference from ASTM temperature difference for 0–10%,10–30%, 30–50%, 50–70%, 70–90%, 90–100%  From established T50(TBP) and using temperature differences, the TBP temperatures at 0, 10, 30, 50, 70, 90,100% are obtained.

Lecture / Dr. Thanh Hai Ngo / Oil Refining Technology

Page 1

3.1.8. Kiến thức bổ sung Maxwell method: TBP-Flash



TBP reference line (DRL): T10 and T70

 Determine T50 of the flash reference line (FRL): ∆T50 (DRL FRL) and DRL slope  ∆T (Flash - FRL) / ∆T (TBP DRL) at each percent volume Flash curve (1atm) is drawn.

Lecture / Dr. Thanh Hai Ngo / Oil Refining Technology

Page 2

3.1.8. Kiến thức bổ sung Probability chart (Thrift)



Estimating ASTM temperatures from any two known values of ASTM temperatures.



The product ASTM curve would be a straight line from 0% to 100% on this graph

Lecture / Dr. Thanh Hai Ngo / Oil Refining Technology

Page 3

AN INTRODUCTION TO CRUDE OIL AND ITS PROCESSING

15

ASTM Temperature Difference °F 210

0

10

20

30

40

50

60

80

70

90

100

110 120

130

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200 190

ASTM Temp Diff vs TBP Temp Diff

180 170

Reference: Edolater-Okanato, Pet, Ref. 38. Number 3, pp 117-129 (1965)

160 150

130

ur

100 n la

%

60

50 40

10 70% 0% t o

60

90 50 % % 30 to % 70 to % 50

til is fD Se

gm

en

to

80 70

70

tio

90

30

90

%

to

50

ASTM 50% Temp vs TBP 50% Temp

40

20

30

10

Reference: Edolater & Pollack, CEP, qs. pp 907 (1948)

20 10 0

∆°F (Add to ASTM 50% to Obtain TBP 50% Temperature)

110

ve 0% , Vo to lum 10 e 10 % Pe % rc to en 30 t %

120

C

TBP Temperature Difference °F

140

0 −10 −20

100

200

300

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500

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900

ASTM 50% Temperature °F

Figure 1.6. ASTM–TBP correlation—Edmister method.

are given as Figures 1.6 and 1.7. In this exercise Edmister’s method and correlation will be used. The ASTM distillation is tabulated as the temperature for IBP, 10%, 20% through to the FBP. IBP is the Initial Boiling Point (equivalent to 0% over) and the FBP is the Final Boiling Point (equivalent to 100% vol over). The multiples of 10% reflect the volume distilled and the temperature at which each increment is distilled. Using Figure 1.6 the 50% vol TBP point (in degrees Fahrenheit) is calculated from the 50% vol point of the ASTM distillation.

16

CHAPTER 1

Slope of Flash Reference Line (FRL) °F/%

8 Prediction of Flash Reference Line From Distillation Reference Lines

7 6

)

BP

5 y sa

4 Fl

de

As

Reference:

2

S. D. Maxwell, "Data on Hydrocarbons" pp 222-228, Van Hostrand Company. New York, 1950.

1 0

vs

h

as

3

u Cr

(T

0

1

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12

110

120

Slope of Crude Assay (TBP) Distillation Reference Line °F/%

∆t'50 (DRL-FRL)

60 Prediction of FRL 50% Point

40 20

t'50DRL>300°F

t'50DRL