UAE University Faculty of Engineering Graduation project II

1. UAE University Faculty of Engineering Graduation project II Waterflooding of Carbonate Reservoirs Advisor: Dr. Ibrahim Kocabas. Masoud Ahmed & Abdulla Salem Final Presentation 10/6/2004

2. Presentation Layout • Introduction, • Objectives, • Types Of Reservoir Formations, • Waterflood Design, • Laboratory Experiments , • Field Design, • Economical Decision, • Environmental & Social Impacts and • Conclusions & Recommendations. Waterflooding of Carbonate Reservoirs

3. Oil Recovery Stages: • Primary. • Secondary (Waterflooding)and • EOR (Enhance Oil Recovery). • Secondary Recovery results from the augmentation of natural energy present in the reservoir through injection of water to displace the oil toward production wells. Waterflooding of Carbonate Reservoirs

4. Secondary Recovery Method (Waterflooding) Waterflooding is the most common method of the Secondary Recovery. Waterflooding of Carbonate Reservoirs

5. Water Is widely available and inexpensive relative to other fluids, easy to inject and efficient in displacing Oil. Waterflooding of Carbonate Reservoirs

6. Why Waterflood is Needed? • Week Natural Reservoir Energy • Under-Saturated Oil Reservoirs. • Negligible Aquifer Support. Low Oil Recovery • Low Permeability Reservoirs • Less than 50 md. High Pressure Drop due to Production Delayed Support from Aquifer (Edge Water) • Large Reservoirs • Less than 50 md. • Heterogeneous Reservoirs • Tar Mates, etc. • Permeability Barriers. Lack of Communication Between Oil and Water Zones. Waterflooding of Carbonate Reservoirs

7. Objectives • Supplementing the natural reservoir energy by pressure maintenance and immiscible fluid displacement. • To design a Waterflooding for fractured Carbonate Reservoirs. • Environmentally safe and Economically feasible. Waterflooding of Carbonate Reservoirs

8. Types of Reservoir Formation • Carbonate • Sandstone • Carbonateis the most common formation in the United Arab Emirates. Waterflooding of Carbonate Reservoirs

9. Waterflood Design Relative Permeability Curve Fractional Flow Curve Lab Experiments CGM Model Field Design Pattern Area Craig-Geffen-Morse Correlation Waterflooding of Carbonate Reservoirs

10. Laboratory Experiments Porosity: Vp = w / ρw A = π (D2/4) VB = A x L Where, Ф : Porosity, fraction. Vp : Pore Volume, cm3 VB : Bulk Volume, cm3 W : Weight of sample, gram ρw : water density = 1.056 gm/cm3. A : cross sectional area, cm2. L : length of core sample, cm. D : Diameter of cores, cm. Waterflooding of Carbonate Reservoirs

11. Laboratory Experiments Permeability: Waterflooding Apparatus Q = Vw / t Where, Q : Flow Rate, cm3 / sec. K : Permeability, darcy. A : Cross-sectional Area, cm2. μ : Water Viscosity, c.p and equals to 1.15 cp. L : Length of sample, cm. dp : Pressure Drop, atm. Vw: Volume of Water collected in the Tube. t : Time, seconds. Waterflooding of Carbonate Reservoirs

12. Laboratory Experiments Core Sample REF1 (Relative Permeability Effect on Fracture) • Porosity (Ф) = 24.5% • Absolute Permeability K = 147 md REF1 (half-Shape Fractured) Waterflooding of Carbonate Reservoirs

13. Laboratory Experiments Core Sample (REF2) Core Sample (REF3) REF2 (T-Shape Fractured) REF2 (T-Shape Fractured) • Porosity (Ф) = 13.7 % • Absolute Permeability K = 24 md • Porosity (Ф) = 21 % • Absolute Permeability K = 63 md Waterflooding of Carbonate Reservoirs

14. Laboratory Experiments Relative Permeability Curve: Waterflooding of Carbonate Reservoirs

15. Laboratory Experiments Fractional Flow Curve: Waterflooding of Carbonate Reservoirs

16. Field Design • Assumptions: • Pattern Spacing = Five-Spot. • Pattern Area (alternatives) = 20-acre and 10-acre. • Thickness = 1 feet. • Pressure Drop = 500 psi. Waterflooding of Carbonate Reservoirs

17. Field Design 20-acre Pattern Spacing Waterflooding of Carbonate Reservoirs

18. Field Design 20-acre Pattern Spacing Waterflooding of Carbonate Reservoirs

19. Field Design 20-acre Pattern Spacing Waterflooding of Carbonate Reservoirs

20. Field Design 10-acre Pattern Spacing Waterflooding of Carbonate Reservoirs

21. Field Design 10-acre Pattern Spacing Waterflooding of Carbonate Reservoirs

22. Field Design 10-acre Pattern Spacing Waterflooding of Carbonate Reservoirs

23. Economical, Environmental andSocial Impacts • Economical Impact: • (Benefit of the Project): Increase the production • Primary Recovery = 15% - 25% • Secondary Recovery (Waterflooding) other 15% – 20% of production. • Total is 30% - 45 % Oil Production. Waterflooding of Carbonate Reservoirs

24. Economical Decision Area = 10 Acres Time of Project = 1.1 years Area = 20 Acres Time of Project =2.3 years • Cost : • * Pipelines and other auxiliaries = 0.25 MM$/well • * Well Cost = 1 MM$ X 4 wells = MM$ 4 • Cost = MM$ 4 + (0.25 MM$/well X 4 wells) = MM$ 5 • Cost : • * Pipelines and other auxiliaries = 0.25 MM$/well • * Well Cost = MM$ 1 X 4 wells = MM$ 4 • Cost = MM$ 4 + (MM$ 0.25 X 4 wells ) = MM$ 5 • Revenue=Np(Mbbl) X Oil Price($/bbl) • Revenue=Np(Mbbl) X Oil Price($/bbl) Np (Oil Produced) = 0.912 MMbbl Oil Price = 25 $/bbl Np (Oil Produced) = 0.457 MMbbl Oil Price = 25 $/bbl • Revenue = 0.457 MMbbl X 25 ($/bbl) • = MM$ 11.4 • Revenue = 0.912 MMbbl X 25 ($/bbl) • = MM$ 22.8 • Profit = Revenue - Cost • = 22.8 – 5 = MM$ 17.8 • Profit = Revenue - Cost • = 11.4 – 5 = MM$ 6.4

25. Economical, Environmental andSocial Impacts • Environmental Impact: • Disposal Water. • Social Impact: • Additional revenues. Waterflooding of Carbonate Reservoirs

26. Conclusions • Waterflooding is a proven oil recovery process. It is not always successful and economically profitable, but there is a sound basis for engineering waterflood projects. • Waterflooding is the most common method of the Secondary Recovery. Recommendations • Back Pressure application displacing missing. • Constant Rate Pumping is missing and • Amott tube equipment is missing. We Would be able to explore imbibition's process much better. Waterflooding of Carbonate Reservoirs

27. 30 minutes Thank you for your Attention Any Questions?