United Arab Emirates University Collage of Engineering Training and Graduation Project Unit

1. United Arab Emirates UniversityCollage of EngineeringTraining and Graduation Project Unit Design a Technique for Investigating the Influence of Initial Oil Saturation on Oil Recovery Using Miscible Flooding Graduation Project II Supervised by : Dr. Shedid A. Shedid May 26th, 2005

2. Team members: 1- Hassan Ali Hussein (200001455 ) 2- Eisa Daban Hamad (980711302 ) 3- Maath Ebrahim Alshehhi (199900386) Examining Committee: Prof. Abdullrazaq Zekri (Department) Dr. Motiur Rahman (Department) Dr. Walid Al-Shorbagi (Collage)

3. Acknowledgments

4. Contents • Introduction • Background Theory • Methods and Techniques with Results & Discussions • Economical Study • Conclusions and Recommendations

5. Introduction • Definition of the problem • Enhanced Oil Recovery (EOR) subdivision • Miscible CO2 injection • Objectives

6. Background Theory • Reservoir Rock Properties: • Porosity. • Permeability. • Mobility ratio.

7. Background Theory • Recovery Methods: • Primary Recovery. • Secondary Recovery. • Tertiary Recovery Methods (EOR). • What is the intent of using EOR? • Improve sweep efficiency. • Eliminate or reduce the capillary.

8. Background Theory Sources of CO2 • Natural CO2 deposits: ammonia plants. • Oilfield gas separation facilities. • Natural gas. • The feasibility of getting CO2 depends on: • Nature of the source • Its location relative to the oilfield • Method of transportation

9. Background Theory • CO2 Miscible Flooding • When does miscibility exist? • What parameters control miscibility? • What does injected miscible CO2 do? • What is miscibility pressure?

10. Background Theory WAG Process: the process of injecting water and gas alternatively with periods of injection1.

11. Background Theory • Factors that make CO2 an EOR agent: • Reduces oil viscosity and increases water viscosity. • Swilling of crude oil and reduction in oil density. • Acid effect on carbonate and shaley rocks: • Carbonic acid dissolves the Ca and Mg carbonates. • Preventing the shales from swelling and causing blockage.

12. Background Theory What are the advantages of using CO2 flooding? • Low pressure for achieving dynamic miscibility with CO2 comparing with natural gas, flue gas, or nitrogen. • Reduction in crude oil viscosity. • Swelling of crude oil and reduction in oil density. • Availability of CO2 as a potential source.

13. Background Theory What are the disadvantages of using CO2 flooding? • CO2 is a costly fluid, project designs usually have called injection of an optimum volume or slug. • Displacement of CO2 by water is immiscible and a residual CO2 saturation is left in the reservoir.

14. Background Theory • CO2 Flood environmental, health, and safety planning

15. Methods and Techniques • The recovery was then calculated as the percentage of the oil produced at CO2 breakthrough. • Intersection of miscible and immiscible lines.

16. Methods and Techniques • Reservoir Rock Properties • Porosity • Procedures: • Dry weight • Evacuate sample • Immersed sample in saline • Saturated weight • Pore and Bulk volume

18. Methods and Techniques • Reservoir Rock Properties • Permeability • Procedures: • Water was added to the accumulator • The core was fixed into the core holder

19. Methods and Techniques • Upstream and downstream pressure • Volume of collected fluid • Time • Plot flow rate against pressure drop

20. Analysis & Results

21. Analysis & Results

22. Methods and Techniques • Reservoir Fluid Properties • Density • Procedures: • Weight of empty Pycnomeater • Weight of Pycnomeater filled with oil

23. Methods and Techniques • Reservoir Fluid Properties • Viscosity (Rolling Ball Viscometer)

24. Rolling Ball viscometer apparatus Methods and Techniques

25. Analysis & Results

26. Analysis & Results

27. Analysis & Results Gas Chromatography Distribution of crude components concentration during retention time

28. Methods and Techniques High Pressure Flooding System

29. Oil Flooding • The core samples should be prepared before starting the flooding process. • Core samples were saturated 100% with water before testing. • Oil flooding. • Determination of IOIP = Displace water.

30. Oil Flooding • Determination of Swir: Irreducible water saturation • Determination of Soi: Initial oil saturation = 1- Swir

31. Analysis & Results

32. Water Flooding

33. CO2 flooding • The system contain: - Heating system - Overburden system - Back pressure system

34. CO2 flooding • The heating system is used to keep the core in high temperature. • The overburden pressure is used to make the CO2 pass through the core. • The back pressure is used to keep the output pressure slightly below the input pressure.

36. The core was fitted in the core holder CO2 flooding • The pump was connected to the system

37. CO2 flooding • The overburden pressure and the back pressure were connected to the system.

38. CO2 flooding • The temperature controller was connected to the system. • The output line was coated with heating wire.

39. CO2 flooding • The pump pressure = 4000 psi • The back pressure = 3900 psi • The overburden pressure = 4500 psi • The temperature = 200o F • The average flow rate = 0.2 ml/min

40. CO2 flooding Sample P2

41. CO2 flooding Results

42. CO2 flooding Results

43. CO2 flooding Results

44. P2 CO2 flooding Results

45. P2 CO2 flooding Results

46. Economical Study • The estimate of CO2 cost is a key component in projecting flood profitability. Why? Because CO2 purchases are the single largest expense in a CO2 flood project. - On average, the cost for CO2 for west Texas projects was 68 % of total costs over the first 10 years of each project.

47. Lab Economic Evaluation

48. Lab Economic Evaluation

49. Field Economic Evaluation

50. Field Economic Evaluation