MINISTRY OF SCIENCE AND TECHNOLOGY
DEPARTMENT OF
TECHNICAL AND VOCATIONAL EDUCATION
Sample Questions & Worked Out Examples
For
PE-05045
FUNDAMENTAL OF ENHANCED OIL RECOVERY
B.E
Petroleum Engineering
1
Ministry of Science and Technology
Department of Technical and Vocational Education
Petroleum Engineering
Sample Questions for
PE-05045 Fundamentals of Enhanced Oil Recovery
1. Write a short note on the principal method of secondary recovery.
(m)
2. Define the following.
(a) Aral sweep efficiency
(b) Mobility ratio
(s)
3. Explain the purpose of testy recovery.
(c)
4. Define the following.
(m)
(a) Contact factor
(b) Displacement efficiency
(s)
5. How many processes are contained in Enhanced oil recovery.
(c)
6. Explain the steam stimulation.
(m)
7. How to calculate cumulative well bore heat losses.
(s)
8. How to calculate average down hole steam quality.
(c)
9. How to calculate average heated radius.
(m)
10. A steam stimulation project is to carried out on a well by injecting 750 bbl/ day of
80% quality steam at 440 F and 390 psig through casing. The data applicable are
as follows:
Well depth
= 1000 ft
Formation thickness
= 10 ft
Geothermal gradient
= 0.1 F/ ft
Thermal conductivity of earth
= 24.3 Btu/ day-ft
Latent heat of steam at 440 F and 390 psig = 780
Specific enthalpy of water at 440 F
= 420 Btu/ lb
Specific enthalpy of water at 85 F
= 90 Btu/lb
Calculate the cumulative well bore heat loss, average down hole steam
quality. and average heated radius of the entire steam injection period of 10 days. (s)
11. Repeat Prob 10 for the steam injection period of 100 days.
(c)
12. Repeat prob 10 injection through the tubing of ID 3 in.
(m)
13. Explain steam flooding.
(s)
14. Describe the performance of steam flooding.
(c)
15. Describe the properties of steam.
(m)
16. Explain heat losses in heat flied injection.
(s)
17. Describe loss of heat in surface facilities.
(c)
18. Describe loss of heat in the well bore.
(m)
19. Calculate the heat water injection rate. The following data are giving:
Injection rate
= 500 bbl/ day
Casing length
= 5000 ft
Geothermal gradient
= 1 F/100 ft of depth
2
Injection for a period of 30 day ft F
Thermal conductivity of formation
= 1.79 Btu/ hr-ft F
specific heat of formation
= 0.619 Btu/ lb F
Density of formation
= 143.5 lb m/hr ft
Water temperature at the surface
= 200 F
Casing size
= 7 in (6.366 in. ID)
Surface temperature
= 70 F
Overall heat transfer coefficient
= 5.6 Btu/ hr
(s)
20. Suppose that 5000 lb/ hr of saturated steam are to be continuously injected in a
single well at 500 psig onto a reservoir under the following conditions.
Pattern area of 5 spot
= 5 acres.
Formation thickness
= 20 ft
Initial water saturation
= 0.20
Residual oil saturation
= 0.10
Steam energy cost
= $ 2.0 mm Btu
Specific heat of rock
= 0.21 Btu/ lb F
water density
= 62.4 lb/ in – ft
Thermal conductivity of base and cap rock = 1.50 Btu/ hr ft
Thermal diffusivity of base and cap rock
= 0.482 sq ft/ hr
Estimate
(a) area swept out in the first 1000 hours,
(b) oil displacement rate at 1000 hours,
(c) economical areal limit for sustained heat application.
(c)
21. For problem 20
(a) time required to reach economical areal limit;
(b) areal sweep efficiency after the project; and
(c) the heat loss as a function of total heat injected.
(m)
22. Explain the application of the heat filled injection.
(s)
23. Describe the advantages of the hot filed injection.
(c)
24. Describe disadvantages of the hot flied injection.
(m)
25. Discuss economic consideration of the hot filed injection.
(s)
26. Calculate the water temperature at 4000 ft after 7 days given the following data;
Hot water injection rate
= 500 bbl/ day,
Injection through 2-in ID tubing, annulus filled with insulating materials.
Overall heat transfer coefficient
= 2.4 Btu/ say-sq-ft F
Geothermal gradient
= 0.02 F/ ft
Surface temperature
= 70 F
Surface injection temperature
= 400 F
Thermal diffusivity of earth
= 0.96 sq-ft/ day
Thermal conductivity of earth
= 33.6 Btu/ lb- F
Specific heat of water
= 1 Btu/ lb- F
(c)
27. Report prob No(26) supposing the injection took place through a 7-in casing. (m)
28. Calculate the wellbore heat loss in Btu/ day which would result when injection
500bbl/ day of high quality steam at 514.7 psig down 2-in nominal diameter
tubing inside 7-in nominal diameter casing, after 10 days if injection. The data
application to the well are as follows:
3
Depth
= 950 ft
Surface temperature
= 70 ºF
Thermal conductivity of formation
= 2.3 Btu/ lb F
Overall thermal conductivity
= 70º F
Rock density
= 167 lb/in ft
Specific heat of rock
= 0.226 Btu/lb ºF
Geothermal gradient
= 0.01 /ft
(s)
29. Repeat problem 0.3 for (a) after 100 days, and (b) after 1 year.
(c)
30. Calculate the total heat loss in the wellbore when high quality system id injected
down tubing set on a packer, and when the annulus is vented, after injection times
of 1,10 and 100 days, for the following conditions;
Depth
= 950 ft
Inside radius of tubing
= 0.833 ft
Steam temperature
= 497 F
Overall thermal conductivity
= 70 Btu/day sq ft F
Thermal conductivity of formation
= 33.6 Btu/day sq ft F
Surface temperature
= 60 F
Rock density
= 125 lb/ in ft
Injection pressure
= 666 psia
Inside radius of casing
= 0.29 ft
Specific heat of formation
= 0.20 Btu/lb F
Geothermal gradient
= 0.0105 F/ft
(m)
31. Repeat the calculation of problem (30) for the case where steam is injected down
the casing.
(s)
32. Calculate the bottom heat temperature for hot water injection times of 1,10, and
100 days for the following conditions;
Depth
= 950 ft
Surface water temperature
= 400 F
Specific heat of formation
= 0.20 Btu/ lb F
Overall thermal conductivity
= 70 Btu/say sq ft F
Surface temperature
= 60 F
Geothermal gradient
= 0.01 F/ft
Thermal conductivity of formation
= 33.6 Btu/day sq ft F
Rock density
= 125 lb/in ft
Inside radius of tubing
= 0.0833 ft
Inside radius of casing
= 0.02 ft
(c)
33. 600 lb/hr of 80% quality steam is injected at 150 psig into a well. The avilable
data follows;
Porosity
= 25%
Initial gas saturation
= 6%
Formation temperature
= 85 F
Specific heat of rock
= 0.20 Btu/lb F
Rock grain density
= 165 lb/in ft
Overburden thermal conductivity
= 1.38 Btu/hr ft F
Overburden thermal diffusivity
= 0.048 sq ft/hr
4
If the cost to generated steam is $0.52 per MM Btu, and the net value of the
oil to the working interest is $ 1.9 per STB after royalty and overhand expenses,
calculate;
(a) The swept area after an injection period of 30 days.
(b) The oil displacement rate at the end of 30 days.
(c) The time when the economic limit is reached.
(d) Area swept out after the economic limit is reached.
(e) Estimate the areal sweep efficiency is the pattern area is 10 acres.
(f) The oil displacement rate at the limited time.
(g) Percent heat loss of total heat injected.
(m)
34. Discuss the Insitu combustion.
(s)
35. Explain the forward combustion.
(c)
36. Explain the reverse combustion.
(m)
37. Describe the reservoir properties necessary for Inst combustion.
(s)
38. Describe the advantage of Inst combustion.
(c)
39. Describe the disadvantage of Inst combustion.
(m)
40. Describe field handling system.
(s)
41. Explain the water treating system.
(c)
42. Explain the surfactant slug blending system.
(m)
43. Explain the fluid injection system.
(s)
44. Describe the advantages of surfactants flooding.
(c)
45. Describe the disadvantage of surfactants flooding.
(m)
46. Define the Mobility Ratio of surfactants flooding.
(s)
47. Describe the advantages of the surfactants flooding.
(c)
48. Describe the disadvantage of the surfactants flooding.
(m)
49. Discuss Caustic flooding.
(s)
50. Explain the advantage and disadvantage of the Miscible hydrocarbon
displacement.
(c)
Ministry of Science and Technology
Department of Technical and Vocational Education
Petroleum Engineering
Worked Out Examples for
PE-05045 Fundamentals of Enhanced Oil Recovery
1.
Explain the Steam stimulation. (Page 6,7,8,9) (I)
2.
Describe the Advantages and disadvantages of steam flooding. (Page 23) (I)
3.
Describe the advantages and disadvantages of insitu-combustion. (Page 39) (I)
4.
Example 3.2 (Page 21,22) (I)
5.
Discuss the field handling systems. (Page 8,9,10) of the surfactant flooding. (II)
6.
Explain the advantages and disadvantages of surfactant flooding. (Page 11) (II)
7.
Describe the advantages and disadvantages of the polymer flooding.
(Page 19,20) (II)
8.
Describe the Caustic flooding. (Page 21,22,23,24) (II)
9.
Explain the advantages and disadvantages of Miscible hydrocarbon
displacement. (Page 27,28) (II)
10.
Explain the advantages and disadvantages of the carbon dioxide miscible
Process. (Page 37,38) (II)