Outline

1. Laboratory core flooding experiments using Bio-surfactant and molasses: Implications for Microbial EOR Mohammad Bahar, Keyu Liu, Abdul Rashid ,Xiaofang Wei, Tara Sutherland, Xiaoyi Wang, Manzur Ahmed, Phil Hendry, Dongmei Li, Se Gong, Herbert Volk, S. Razak, Wan Ata, A Azhan,M.Rizal CSIRO Wealth from Ocean Flagship and Petronas Research

2. Outline • Background • Objectives • Materials and methods • Results and discussion • Conclusions 30th IEA Annual Workshop and symposium on EOR -Canberra

3. Oil Recovery Mechanisms CONVENTIONAL RECOVERY PRIMARY RECOVERY Natural Flow Artificial Lift (Pump, Gas Lift, etc.) SECONDARY RECOVERY Waterflood Pressure Maintenance (Water, Gas Reinjection) EOR TERTIARY RECOVERY Other Thermal Solvent Chemical MEOR Adapted from the Oil & Gas Journal, Apr 23, 1990 30th IEA Annual Workshop and symposium on EOR -Canberra

4. EOR vs. Permeability EOR Method Permeability (md) 10 100 1,000 Not critical if uniform Hydrocarbon Miscible Not critical if uniform Nitrogen and Flue Gas High enough for good injection CO2 Miscible Surfactant Polymer Polymer Alkaline Fireflood Steam Drive MEOR Dr. Larry Lake, Oilfield Review (Jan. 1992) Good Possible Fair Difficult Not Feasible 30th IEA Annual Workshop and symposium on EOR -Canberra

5. Oil Gravity vs. EOR Methods Oil Gravity oAPI 0 10 20 30 40 50 60 N2 & Flue Gas Hydrocarbon CO2 - Miscible Immiscible Gas Alkaline/Surfactant/Polymer Polymer Flooding Gel Treatments MEOR Steam Flooding Mining (Modified from J.J. Taber, F.D. Martin & R.S. Seright, 1997) 30th IEA Annual Workshop and symposium on EOR -Canberra

6. What is MEOR and its Potential on EOR? • Microbes can be introduced into oil reservoirs, and/or indigenous microbes can be stimulated with nutrients. Potentials: • Changing fluid properties such as Density, Viscosity, composition and IFT • Changing the rock properties such as wettability , permeability and relative permeability • Changing conditions of system (pressurize, 30th IEA Annual Workshop and symposium on EOR -Canberra

7. Background: Can MEOR be a successful method for EOR? Initial With biosurfactant (above CMC) S.M. Farouq Ali- University of Calgary-2003 30th IEA Annual Workshop and symposium on EOR -Canberra

8. Microbiology Microbial physiology Microbial metabolisms Isolation and culture Organic Geochemistry Develop analytical protocol identify/quantify metabolites Overview of CSIRO’s MEOR project Modelling Analyse/verify experimental results Build predictive model for MEOR Build reservoir model for field trial before and after Microorganisms treatments Measuring fluid physical properties, such as density, viscosity and IFT Measuring rock physical properties K, Krw, Kro, Measuring EOR 30th IEA Annual Workshop and symposium on EOR -Canberra

9. Objectives • Monitor changes in oil and water physical properties after culture experiments • Detect and quantify various by-products - Gases - Bio-surfactants - Acids - Co-biosurfactants - Polymer - Oil Degradation • Select suitable nutrients to stimulate microbial growth and production of metabolites leading to MEOR • Undertake core flooding experiments 30th IEA Annual Workshop and symposium on EOR -Canberra

10. Material and methods • Reservoir fluids from Off-shore Malaysian oil-field - Depth: ~ 720 m - Temperature: 50ºC - Salinity: 2.3 % - Mature, high water cut - Reservoir Pressure: 940 Psia 30th IEA Annual Workshop and symposium on EOR -Canberra

11. Experiment : Core Flooding Setup 30th IEA Annual Workshop and symposium on EOR -Canberra

12. Experimental sequences Water Measuring volume of Water Oil Gas Oil Core Holder Water Molasses Water 30th IEA Annual Workshop and symposium on EOR -Canberra

13. Effects of biosurfactant on water densities No effects 30th IEA Annual Workshop and symposium on EOR -Canberra

14. Effects of bio-surfactant on viscosity of Bokor formation water(104LS) H2O viscosity increases with BS concentrations 30th IEA Annual Workshop and symposium on EOR -Canberra

15. Effect of bio-surfactant (Surfactin) on IFT(104LS) at 50 °C 940psi 30th IEA Annual Workshop and symposium on EOR -Canberra

16. MEOR core flooding results Swir=14%; Primary oil recovery: 74.4% Soir=25.6%; incremental EOR: 4.1% 4.1% MEOR Sor=25.6% 30th IEA Annual Workshop and symposium on EOR -Canberra

17. Which phenomena is more reliable? Increasing production 4% Injecting Molasses ? 30th IEA Annual Workshop and symposium on EOR -Canberra

18. What types of by-products were produced? • Gases • Alcohols • Acids • Bio-surfactants • Micro-emulsion 30th IEA Annual Workshop and symposium on EOR -Canberra

19. Gases and swelling • A large reduction in oil viscosity and small increase in water viscosity The Young – Laplace Equation predicts an inverse relation of pressure drop with Swelling of Oil 30th IEA Annual Workshop and symposium on EOR -Canberra

20. Distribution of microbial gases • Stimulation by carbohydrates produced substantial amounts of CO2 and CH4 gases • C2+ gases desorbed from oil? Concentration (ppm) CO2 CH4 C2H6 C3H8 C4H10 30th IEA Annual Workshop and symposium on EOR -Canberra

21. CO2 CH4 Concentration (ppm) (Control) Duration of culture (days) Microbial gases • Very high amounts of CO2 and CH4 gases produced • CO2 generation continued to increase until after 9 days • CH4 generation continued to increase until after 11 days 30th IEA Annual Workshop and symposium on EOR -Canberra

22. ng/mL of water 2 (Control) 2 4 7 9 11 14 16 18 20 22 Duration of culture (days) Alcohols production • Variable amounts of alcohols produced • Generation continued to increase until after 16 days of culture • A second cycle of moderate generation initiated after 18 days 30th IEA Annual Workshop and symposium on EOR -Canberra

23. ng/mL of water 2 (Control) 2 4 7 9 11 14 16 18 20 22 Duration of culture (days) Acids production • Variable amounts of acids produced • Consistent with gases and alcohols, generation continued to increase until after 16 days of culture • A second cycle of intense generation initiated after 18 days 30th IEA Annual Workshop and symposium on EOR -Canberra

24. Micro-emulsion experiment using co-surfactant 30th IEA Annual Workshop and symposium on EOR -Canberra

25. Surfactants at the Solid-Liquid Interface Low Concentration - Surfactant Adsorption Clay Moderate Concentration - Hemimicelle Formation Clay High Concentration - Self-Assembled Surface Aggregates Clay Clay 30th IEA Annual Workshop and symposium on EOR -Canberra

26. surfactants Solubility of alcohol in micelles Oil rim Water droplets 30th IEA Annual Workshop and symposium on EOR -Canberra

27. Bio-surfactants w/o emulsion Micelles 30th IEA Annual Workshop and symposium on EOR -Canberra

28. Oil Water droplets 30th IEA Annual Workshop and symposium on EOR -Canberra

29. Water droplets with oil rim Oil droplets in water droplets 5 mm 30th IEA Annual Workshop and symposium on EOR -Canberra

30. Interfacial tension and capillary pressure • Surfactant Reduce interfacial tension in small pore and reduce the capillary pressure in the system R1=2 Y=2 P=(2*2)/2=2 R2=1 Y=1 P=(2*1)/1=2 30th IEA Annual Workshop and symposium on EOR -Canberra

31. Conclusions • Microorganisms can change the threshold point of residual oil in reservoirs and to enhance oil recovery: • Core flooding using 40 ppm surfactin enable 3% EOR • Core flooding using 0.875% molasses enable 4.1% EOR • MEOR uses a combination of mechanisms to recover residual oils in reservoirs including • Gas production can reduce oil viscosity • Biosurfactant production can reduce IFT • Solvents and biosurfactants can promote micro or nano emulsion • Produced biosurfactants may change the wettability of clay rocks • MEOR could become a low cost environmental friendly EOR method in the future but more research is required 30th IEA Annual Workshop and symposium on EOR -Canberra

32. Contact Us Phone: 1300 363 400 or +61 3 9545 2176 Email: enquiries@csiro.au Web: www.csiro.au Thank you Wealth from Ocean Flagship Mohammad Bahar Reservoir Engineer Phone: 08 64368954 Email: mohammad.Bahar@csiro.au Web: www.csiro.au/science/MEOR.html