1. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS A Web-Based Platform for Solution of Generalized Gas- Lift Optimization Problems Augusto M. de Conto

2. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Summary Generalized lift-gas allocation problem Effective mixed-integer formulations State-of-the-art algorithms User-friendly web interface

3. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS New Field Reservoir Oil + Gas + Water Separator Tubing Casing

4. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Mature Field Reservoir Separator Tubing Casing Oil + Gas + Water

5. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Artificial Lift Beam Pump Electric Submersible Pump Gas Lift

6. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Gas Lift High pressure gas is inject into the production tubing Reduce the density of fluid column Stimulates natural flow

7. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Well Performance Curve (WPC) Polynomial Alarcón et al. (2002) Nakashima et al. (2005)

8. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS WPC Piecewise Linear Formulation

9. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Typical Gas Lift Objectives Production maximization Profit maximization Cost minimization subject to production quota

10. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Gas Lift Field

11. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Typical Gas Lift Constraints Limited lift-gas injection rate

12. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Typical Gas Lift Constraints Limits on oil, gas and water handling capacities

13. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Typical Gas Lift Constraints Different gas-lift performance curves for each well Lower and upper bounds on gas-lift injection Activation constraints

14. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Literature Review Kanu et al. (1981): Equal-slope method Nishikiori et al. (2002): SQP – non-linear optimization Martínez et al. (1994), Buitrago et al. (1996): heuristic methods Nakashima (2005): Dynamic Programming Camponogara (2005): Mixed-Integer Linear Programming

15. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Objective Function N: number of wells p o, p g : profit per produced barrel of oil and gas p w,p i : water treatment and gas compression cost γ o n, γ g n, γ w n : fractions of oil, gas and water produced by well n q p n : production rate of well n q i n : gas injection rate for well n

16. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Facility Constraints  Available gas injection rate Compressor capacity

17. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Facility Constraints  Total separation capacity  Oil handling limit  Water handling limit  Gas handling limit Separator capacity

18. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Precedence Constraint 1 2 45 3 6 7 89

19. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Our Contribution P 5 (G) Objective Multiple facility constraints Precedence constraint

20. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Our Contribution P 5 (G) P 5 (ø) MILP Multiple facility constraints No precedence

21. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Our Contribution P 5 (G) P 1 (G)P 5 (ø) MILP Compressor capacity constraint Precedence constraint

22. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Our Contribution P 5 (G) P 1 (G) P(ø) DP MILP P(F) DP MILP P(G) DP MILP P 5 (ø) MILP current research

23. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Web Based Interface Interface that allows user to specify information about the well field and run optimization algorithms Need of an environment to call optimization algorithms –Friendly –Transparent –Expansible

24. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Interface Structure User local interface User local interface Optimization server Optimization server localremote Web

25. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Local Well field specification Automatically converts optimization models Operational System free User local interface User local interface local

26. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Remote Run optimization algorithms Heavy algorithms requires high memory and processing capacity Usage of non freeware optimization tools Optimization server Optimization server remote

27. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Interface

28. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Interface

29. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Interface

30. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Interface

31. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Interface

32. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Comparative Results Wellsq p (B/D)q i max (MSCF/D) PLM gain SQP5537.2184,9500.000 % PLM537.21 SQP137,708.0322,4840.000 % PLM7,708.02 SQP2516,872.8954,425-0.004 % PLM16,872.21 SQP3721,212.7972,497+0.016 % PLM21,216.19 Mean11,583.0758,589+0.003 % Wells with natural flow

33. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Comparative Results Wellsq p (B/D)q i max (MSCF/D)PLM gain SQP124,125.976,00024.57 % PLM5,139.77 SQP248,198.7512,0007.87 % PLM8,844.55 SQP3615,647.8218,0003.24 % PLM16,155.50 SQP4823,135.5524,0002.03 % PLM23,605.20 SQP5625,874.1430,0002.45 % PLM26,507.70 Mean15,723.5618,0008.03 % Wells without natural flow

34. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Conclusions Interface allows users runs lift-gas allocation problem with no specific knowledge of the formulation

35. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Bibliography E. P. Kanu, et al.: “Economic Approach to Oil Production and Gas Allocation in Continous Gas Lift”, SPE Paper 9084, 1982. N. Nishikiori, et al.: “An improved method for gas lift allocation optimization”, SPE Paper 19711, 1989 E. R. Martínez, et al.: “Application of Genetic Algorithm on the Distribution of Gas Lift Injection”, SPE Paper 2481, 1994. S. Buitrago, et al.: “Global Optimization Techniques in gas Allocation for Continuous Flow Gas Lift Systems”, SPE Paper 35616, 1996. G. A. Alarcón, et al.: “Global Optimization of Gas Allocation to a Group of Wells in Artificial Lift Using Nonlinear Constrained Programming”, ASME Journal of Energy Resources Technology, 2002

36. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS Bibliography G. A. Alarcón, et al.: “Global Optimization of Gas Allocation to a Group of Wells in Artificial Lift Using Nonlinear Constrained Programming”, ASME Journal of Energy Resources Technology, 2002 P. Nakashima, et al. “Optimization of Lift-Gas Allocation Using Dynamic Programming”, Accepted to appear in IEEE Transactions on Systems, Man and Cybernetics, Part A, 2005

37. STUDENT PRESENTATION CONTEST 2005 STUDENT CHAPTER OF CAMPINAS A Web-Based Platform for Solution of Generalized Gas- Lift Optimization Problems Augusto M. de Conto Thank you!