Parametric SCAL modeling

Transcription

1 Parametric SCAL modeling Frode Lomeland Leading Advisor Reservoir Flow Parameters Statoil Stavanger 14 November 2013 Classification: Internal

2 Outline Introduction Workflow Trend functions and analysis Local trend curves and saturation regions (bins) Extension of SCAL model to include Hamon s theory Quality control and deliveries Short summary of benefits of parametric SCAL modeling 2

3 SCAL contributions to IOR / EOR 1 Special core analysis (SCAL) is a study of multi-phase fluid flow in rock Traditionally SCAL studies involves laboratory experiments, and deliver a model for reservoir flow parameters (RFP or SCAL model) that is used in the reservoir simulator Most IOR / EOR methods try to produce remaining oil left behind injection front by the original drainage plan produce oil that is not swept by the original drainage plan A high quality SCAL model is therefore recommended 3

4 SCAL contributions to IOR / EOR 2 A high quality SCAL model means more correct reference when evaluating other injection fluids as EOR more correct reservoir flow parameter model which means more correct reservoir simulation model which means better prediction of remaining oil production for existing drainage plan better understanding and prediction of remaining targets for in-fill drilling One way of preparing high quality SCAL models is to use parametric SCAL modeling 4

5 Short on parametric SCAL modeling : Parameterize SCAL properties, relative permeability and capillary pressure, based on formulas that can be used for all scales - from the small pore scale or core plug scale and up to the large scale of grid cells in full field models. : Relative permeability and capillary pressure are represented parametrically by the LET family of formulas (LET is a reference to the three authors in the first paper on these formulas). Interpreted laboratory results are stored in a parametric SCAL database. Trend analysis of SCAL parameters are significantly improved, and consistent SCAL models with uncertainty are generated. Both up-scaling of SCAL data and history matching of multiphase flow are improved and facilitated by using the parametric LET representation (not discussed in this presentation). SCA Lomeland, Ebeltoft and Thomas

6 Work flow for SCAL modeling Eclipse Laboratory data e-core Sendra (Kr, Sr, Pc) Numeric interpretation of exp Servilia (Pc) Pc curves, scalars, exp data Cleopatra (Kr, Sr) Kr curves, scalars, exp data Caesar parameters & scalars Hadrian scalar & curve generator Eclipse & Stars

7 Work flow for SCAL modeling Eclipse Laboratory data e-core Sendra (Kr, Sr, Pc) Numeric interpretation of exp Servilia (Pc) Pc curves, scalars, exp data Cleopatra (Kr, Sr) Kr curves, scalars, exp data Caesar parameters & scalars Hadrian scalar & curve generator Eclipse & Stars

8 Work flow for SCAL modeling Eclipse Laboratory data e-core Sendra (Kr, Sr, Pc) Numeric interpretation of exp Servilia (Pc) Pc curves, scalars, exp data Cleopatra (Kr, Sr) Kr curves, scalars, exp data Caesar parameters & scalars Hadrian scalar & curve generator Eclipse & Stars

9 Work flow for SCAL modelling Eclipse Laboratory data e-core Sendra (Kr, Sr, Pc) Numeric interpretation of exp Servilia (Pc) Pc curves, scalars, exp data Cleopatra (Kr, Sr) Kr curves, scalars, exp data Caesar parameters & scalars Hadrian scalar & curve generator Eclipse & Stars

10 Work flow for SCAL modeling Eclipse Laboratory data e-core Sendra (Kr, Sr, Pc) Numeric interpretation of exp Servilia (Pc) Pc curves, scalars, exp data Cleopatra (Kr, Sr) Kr curves, scalars, exp data Caesar parameters & scalars Hadrian scalar & curve generator Eclipse & Stars

11 PAI selection Filter to field / litho-stratigraphic formation or group Kabs vs Swir Porosity vs Swir PAI - Porosity, Absolute permeability, Irreducible water saturation

12 Trend analysis promotes more saturation regions Increasing S wir in saturation end-point scaling gives an increased curvature of K row This is opposite of what flow parameters from SCAL experiments show Increasing S wir in trend analysis shows a smaller L-parameter for K row I.e. a more water wet system with less curvature Flow parameters vs. S wir Curve shape parameters, end-point saturations and end-point relative permeability values are flow parameters Residual saturation vs. S wir

13 Trend analysis promotes more saturation regions Increasing S wir in saturation end-point scaling gives an increased curvature of K row This is opposite of what flow parameters from SCAL experiments show Increasing S wir in trend analysis shows a smaller L-parameter for K row I.e. a more water wet system with less curvature Curve shape parameters, end-point saturations and end-point relative permeability values are flow parameters

14 Trend analysis promotes more saturation regions Increasing S wir in saturation end-point scaling gives an increased curvature of K row This is opposite of what flow parameters from SCAL experiments show Increasing S wir in trend analysis shows a smaller L-parameter for K row I.e. a more water wet system with less curvature Flow parameters vs. S wir Curve shape parameters, end-point saturations and end-point relative permeability values are flow parameters Residual saturation vs. S wir

15 Basic definitions WOGn WOGn - notation: Bookkeeping system for the flooding processes. It consists of a triplet W-O-G - and a cycle number - n. The positions in the triplet are fixed and reserved for Water, Oil Gas Each position state the phase-saturation change - D, I or C meaning Decreasing, Increasing or Constant The nomenclature is prepared for higher cycles to complete multi-cycle hysteresis boundary curves

16 Local trend curves: IDC2 Krwr SS+USS Calibration point moved to an abnormal position for visualization purposes Flooding CFG+PP 16 Classification: Internal

17 Local trend curves: IDC2 Sendra hist. match 17 Classification: Internal

18 Saturation regions and flow parameter values ATZ ATZ Above (capillary) Transition Zone 18 Classification: Internal

19 Initialization of Sw and Flow Parameters Chart from Ghedan 2012 Corey exponents vs depth ATZ = Above Transition Zone CTZ = Capillary Transition Zone ATZ CTZ 19 Hamon SPE MS Chart from Ghedan 2012

20 Saturation regions and RFP values in CTZ 20 Hamon SPE MS

21 Kr are distributed vs Swinit via SATNUM Wettability changes vs height above WOC and permeability Above capillary transition zone In capillary transition zone 21 Hamon SPE MS

22 QC using global trend functions 22 Classification: Internal

23 Relative permeability with uncertainty 23 Classification: Internal

24 Benefits of parametric SCAL modeling : Special core analysis (SCAL) is a cornerstone in modeling multiphase flow of injection strategies for both basic and improved oil recovery processes. Improved SCAL models imply more reliable reservoir simulation results. Proper SCAL models may improve the simulation of reservoir performance and the quantification of SCAL related uncertainties, possibly worth billions of dollars. The distinct advantages of using a parametric description of SCAL properties, far outweigh the disadvantages of minor loss of quality of the selected formulas (or correlations) when doing trend analysis in a large database. : Implemented as an evaluation tool in Statoil s portfolio Statoil is probably industry leader within parametric SCAL evaluation and modeling

25 Basic elements of parametric SCAL modeling Classification: Internal

26 Presentation title Presenters name Presenters title Tel: Classification: Internal

27 Work flow for SCAL modeling Eclipse Laboratory data e-core Sendra (Kr, Sr, Pc) Numeric interpretation of exp Servilia (Pc) Pc curves, scalars, exp data Cleopatra (Kr, Sr) Kr curves, scalars, exp data Caesar parameters & scalars Hadrian scalar & curve generator Eclipse & Stars

28 Key Publications Lomeland F., Ebeltoft E. and Thomas W.H.: A New Versatile Relative Permeability Correlation. Paper SCA , International Symposium of the Society of Core Analysts held in Toronto, Canada, August, Lomeland F. and Ebeltoft E.: A New Versatile Capillary Pressure Correlation. Paper SCA , International Symposium of the Society of Core Analysts, Abu Dhabi, UAE, 29 October 2 November, Lomeland F., Hasanov B., Ebeltoft E. and Berge M A Versatile Representation of Up-scaled Relative Permeability for Field Applications. Paper SPE MS presented at the EAGE Annual Conference & Exhibition incorporating SPE Europec held in Copenhagen, Denmark, 4-7 June Lomeland F. and Ebeltoft E.: Versatile Three-phase Correlations for Relative Permeability and Capillary Pressure. Paper SCA , International Symposium of the Society of Core Analysts, Napa Valley, California, USA, September, Classification: Internal