Safety and Security for CO 2 Geological Storage while CO 2 /H 2 O/Rock Reaction

1. Safety and Security for CO2 Geological Storage while CO2/H2O/Rock Reaction Bo Peng Enhanced Oil Recovery Research Center, China University of Petroleum, Beijing, China Sep.23, 2009 Canberra,Australia

2. Content • 1. Background • 2. CO2 and Salt Solution Reaction • 3. CO2 and Rocks Reaction • 4. Wettability of the Rock • 5. Permeability of the Rock • 6. Safety and Security for CO2 Storage • 7. Conclusion

3. 2-3℃ ② ① 1.Background 1.Reduction of Green House Gas Emission---A topic which concerned around the world nowadays. Carbon Capture and Storage(CCS) is one of the most important technology.

4. 1.Background 2. Chinese Government Concerns Greatly about Reduction of CO2 Emission and Utilization of It as Resources • Chairman Hu Jintao • Primer Wen Jiabao • “973”, “863” Reseach Projects…. • Petrochina,HuanengPilot Test….

5. 1.Background 3. CO2 Storage and EOR in China • Oil&Gas Reservoir, Subsurface Salaquifer, coal bed,ideal Place for CO2 Storage • 923 billion tons of CO2 can be storaged in reservoir, which is45%of global cumulative emission in 2050.

6. 1. Background 4. Safety and Security for CCS have attracted more and more attention.

7. 1. Background

8. 2. CO2 and Salt Solution Reaction NaCl Na2SO4 MgCl2 Salt Solution (Aqueous Solution) Daqing Formation Water CaCl2 CaCO3 Ca(HCO3)2 Pressure The Effect Factors Tempreture

9. 2 3 4 7 C 1 5 8 6 2. CO2 and Salt Solution Reaction pH Measurement System in Higher Pressure 1. CO2 ；5.Higher Pressure Vessel；8. pHS－3C Meter

10. 2. CO2 and Salt Solution Reaction pH≈3.0 CO2:H2CO3in Water, NaCl Solution Na2SO4 Solution Effect on pH by Pressure on Aqueous Systems (25℃)

11. 2. CO2 and Salt Solution Reaction pH≈3.0 CO2:H2CO3in Water, MgCl2 Solution CaCl2 Solution ≈ Effect on pH by Pressure on Aqueous Systems (25℃)

12. 2. CO2 and Salt Solution Reaction pH≥3.0 CO2:HCO3－in Water, Na2CO3 Solution NaHCO3 Solution Effect on pH by Pressure on Aqueous Systems (25℃)

13. 2. CO2 and Salt Solution Reaction pH≥3.5 CO2:HCO3－in Water, Daqing Formation Water（mg/L）

14. 2. CO2 and Salt Solution Reaction pH decrease while T goes up. H2CO3 give more H+ 10% MgCl2 10% CaCl2 Effect on pH by Temperture on Aqueous Systems

15. 3. CO2 and Rocks Reaction Rock Surface Topographic Image H2O + CO2 Calcite Pieces Formation of the Solution Formation of the Solution H2O + CO2 Calcite Powders Permeability of Sand Pipe Rock Surface Topographic Image SEM Ions Spectrum Formation of the Solution Permeability Measurement Unit Permeability of Sand Pipe

16. P1 P2 取样 1 2 • 3 4 3. CO2 and Rocks Reaction 1.CO2；3.Reaction Vessel ；4.Heating System； Reaction Unit in High Pressure

17. 3. CO2 and Rocks Reaction Calcite:97.8%；Dolomite:2.2% Rock Characteristic

18. 3. CO2 and Rocks Reaction After Reaction Before Reaction Pressure：2 MPa；Temperature：25 ℃；Reaction Time：20days Rock Surface Topographic Image

19. 3. CO2 and Rocks Reaction After Reaction Before Reaction Pressure：2 MPa；Temperature：25 ℃；Reaction Time：20days Rock Surface Topographic Image

20. 3. CO2 and Rocks Reaction Ion in the solution before/after CO2 and Rock Reaction（ mg/L） Pressure：2 MPa；Temperature：25 ℃；Reaction Time：20days Rock Surface Topographic Image

21. 3. CO2 and Rocks Reaction Ca2+,HCO3-↑. 8 days Stably Pressure：2 MPa；Temperature：25 ℃； Ions in Formation Water

22. 3. CO2 and Rocks Reaction Pressure：2 MPa；Temperature：60℃； Ions in Formation Water

23. 3. CO2 and Rocks Reaction CO2↑ Pressure：2 MPa；Temperature：90℃； Ions in Formation Water

24. 4. Wettability of the Rock Non-ion water CO2 Contact Angle Daqing Formation Water CO2 Contact Angle Rock Pieces + Dilute Daqing Formation Water NaCl CO2 Contact Angle CaCl2 CO2 Sand Core + Daqing Formation Water Permeability of Sand Core

25. 4. Wettability of the Rock Silica Sand:97.7%；Potash feldspar:0.6%； Calcite:0.1%Dolomite:0.6%others:1%；

26. 4. Wettability of the Rock Non-ions Contact Angle: Rock Pieces + Non-ions+ CO2 Pressure：1MPa Tempreture：25 ℃ θa0 –No-CO2；θa – CO2 ；θa1 – Water Treatment

27. 4. Wettability of the Rock Contact angle ↓。 Daqing Formation Water Contact Angle: Rock Pieces + Non-ions+ CO2 Pressure：1MPa Tempreture：25 ℃ NO CO2, NO Contact Angle Change. θa0 –No-CO2；θa – CO2 ；θa1 – Water Treatment

28. 4. Wettability of the Rock More Daqing Water, More change on contact angle Pressure：1 MPa Tempture：25 ℃ Effect of Ions on Contact Angle

29. 4. Wettability of the Rock NaCl CaCl2 Pressure：1 MPa Tempture：25 ℃ Effect of Ions on Contact Angle

30. 5. Permeability of the Rock 1.N2 2.CO2 3. 5.Sand Filling Model 6. Pumper

31. 5. Permeability of the Rock Silica Sand:98.1.7%；Potash feldspar:0.3%； Calcite:0.3% Dolomite:1.2%others:0.1%；

32. 5. Permeability of the Rock L ：50. 24 mm ；D: 25 .00 mm；S：25.57%；T：30℃ CO2 Increase the permeability。 L：51.60mm；D：25 mm；S：31.23%；T：30℃ Effect of CO2 on permeability of Sand Core

33. 5. Permeability of the Rock P:2MPa；Reaction T: 65℃；Test T：25 ℃ Silica sand: Calcit=1：1 Effect of CO2 on Permeability of Sand Filling Model

34. 6.Safety and Security for CO2 Storage

35. 6.Safety and Security for CO2 Storage

36. 6.Conclusion 1. After carbon dioxide injection, pH of single brine, Daqing modeled water dropped and then gradually decreased to a steady value. Magnesium chloride and calcium chloride solution (wt%=10%) pH decreased with temperature increase. 2. The SEM study shows that dissolution occurs on calcite surface. The Ca2+ and HCO3- concentration increased with reaction time to steady values. The time reach to steady is shorter with temperature increase. 3. The permeability of sand pipe filled with calcite and quartz increased with reaction time. • When inject into CO2, contact angle of cores slice in Daqing modeled water decreased and the proportion of Daqing modeled water is bigger, the change of contact angle is bigger. • The Safety and Security for CO2 Storage is correlated to the CO2/H2O/Rocks Reactions

37. Thanks for your attention!