Wettability of carbonate reservoir minerals under carbon storage conditions

Transcription

1 TCCS-9 Wettability of carbonate reservoir minerals under carbon storage conditions Dr Mihaela Stevar and Prof Martin Trusler 13 June

2 Outline Background Objectives Experimental part Results Concluding remarks 2

3 Background Importance of interfacial properties in carbon storage Capture Transport Storage/Injection Saline aquifers Depleted oil fields Systems of interest Brine CO 2 Brine CO 2 Mineral Oil CO 2 Oil CO 2 Mineral Trusler, Annu. Rev. Chem. Biomol. Eng :

4 Background Importance of interfacial properties in carbon storage Overview of a conceptual storage site and different A possible relationship between different trapping mechanisms trapping mechanisms and time 4

5 Background Importance of interfacial properties in carbon storage Interfacial tension,γ and contact angle,θ determine the capillary entry pressure p c for a pore of radius r, and thus the over pressure needed to displace brine by CO 2 during an injection process. p c = p CO2 p brine = 2γ brine CO 2 cos θ Young-Laplace equation: R Interfacial properties influence the amount of CO 2 that can be injected and play a key role in determining storage capacity and security. Structural trapping the wettability controls the ability of CO 2 to enter the caprock Residual trapping mechanism tends to be suppressed for more neutrally wet systems Iglauer et al., WRR,

6 Background Interfacial tension Systems of interest H 2 O CO 2 (Georgiadis et al.) Brine CO 2 (Li et al.) H 2 O X (Chow et al.) H 2 O CO 2 + X, X = N 2, Ar, H 2 (Chow et al.) Pendant drop method γ: interfacial tension Δρ: density difference between phases R 0 : radius of curvature at drop apex β: dimensionless shape factor g: gravitational acceleration Wettability & Contact angle Spreading θ = 0 cos θ = 1 Complete wetting S > 0 Partial wetting S < 0 γ SL = γ SV θ = 90 cos θ = 0 Negligible wetting Non-wetting θ = 180 cos θ = -1 6

7 Background Wettability & Contact angle Static method Sessile drop Young equation: Ramé-Hart Instrument Co. γ SV = γ SL + γ LV cos θ Young Dupré equation: S = γ LV cos θ 1 Dynamic methods Add and remove volume & Tilting base CA Hysteresis: H = θ a θ r Ramé-Hart Instrument Co. 7

8 Background Literature data Calcite (Limestone) Iglauer et al., WRR, Water and brine CAs on calcite compiled from Bikkina, 2011; Jung and Wan; 2012; Espinoza and Santamarina, 2010; Farokhpoor et al., 2013; Wang et al., 2013a and Mills et al.,

9 Background Literature data Calcite (Limestone) Limestone p = 10 MPa T = 323 K Pore scale CA measured using X-ray microtomography. Andrew et al., AWR,

10 Objectives Wettability of carbonate minerals Reactive system: CO 2 + H 2 O + Calcite Analogue system in which the mineral dissolution reaction is inhibited: CO 2 + NaHCO 3(aq) + Calcite CaCO CaCO CaCO H H 2 Ca CO Ca * CO Ca CO 2 + H 2 O + NaHCO 3 Modelling to saturation 373 K, 6 MPa HCO HCO H 2 CO 3 * is the sum of dissolved molecular CO 2 (aq) and H 2 CO 3 in the aqueous system 3 k k k Cleaved & polished calcite NaHCO 3(aq) 1 mol/kg T = ( ) K, p 30 MPa Data provided by PhD Benaiah Anabaraonye 10

11 Experimental part Experimental setup V5 V4 F6 P1 V6 V7 Liq. 1 Liq. 2 F7 P2 V10 V1 F8 V16 V17 V18 F17 F18 F19 F14 F15 F16 V13 V14 V15 V9 Vacuum Pump F9 F22 F10 V8 F11 F12 V12 F13 F21 TT1 F20 F2 F1 View Cell F3 V11 He Gas 1 Gas 2 Vacuum V/L Separator V19 Drain V/L Separator V3 V2 F5 PT1 F4 F23 To Lab Vent 11

12 Experimental part Experimental setup Magnetic manipulator Sessile drop and tilting plate methods were used for static and dynamic CA measurements 12

13 Experimental part Validation measurements Substrate p / MPa T / K θ / θa / θr / PTFE Stainless steel These results are in good agreement with previous literature data Calcite substrates preparation Cleaved calcite substrates immobilization within resin (Stycast1090/Catalyst11) and their mounting in the support 120 o C rt. 13

14 Results Static CA, sessile drop method 14

15 Results Static CA for CO 2 + NaHCO 3(aq) + Calcite at various T p = 10 MPa 15

16 Results Dynamic CA, tilting plate method Tilt angle 0 Roll off angle 37 16

17 Dynamic CA, tilting plate method t = 0 Results t = 44 t = 89 17

18 Calcite substrates surface analysis Optical microscopy SEM/EDS p = 6 MPa T = 333 K Results a) b) c) Microscope images of: a) smooth, b) slightly rougher and c) rough sections of 3 different calcite substrates cleaved in identical manner showing the potential variation in roughness of identically cleaved crystals 18

19 Results Calcite substrates surface analysis SEM/EDS p = 10 MPa T = 333 K 19

20 Results Calcite substrates surface analysis SEM/EDS p = 20 MPa, T = 333 K 20

21 Results Static & Dynamic CA, cleaved vs polished calcite, 333 K Cleaved Calcite {104} Polished calcite, 1 μm 21

22 Concluding remarks Based on the results obtained so far it appears that calcite can be either brine-wet or intermediate/weakly CO 2 -wet depending on the p, T conditions A brine trace appears to be deposited on the substrates, most likely during the depressurization stage Additional data are required for polished calcite substrates in order to determine the influence of roughness 22

23 Acknowledgements Thank you for your attention! We gratefully acknowledge the funding of QCCSRC provided jointly by Qatar Petroleum, Shell, and the Qatar Science & Technology Park 23