15Outline Introduction Problem statement Literature review Objectives 4/12/2017OutlineIntroductionProblem statementLiterature reviewObjectivesOverview of the studyLaboratory ExperimentsModelingConclusionsRecommendations
164/12/2017Problem StatementLack in understanding of upscaling laboratory imbibition experiments to field dimensionsWetting behavior- Low rock permeability thatrepresent real thing- Static and dynamicprocess- Reservoir conditions
17Literature Review4/12/2017rock characteristics (Mattax and Kyte, 1962; Torsaeter, 1984; Thomas 1984; Hamon and Vidal, 1988)fluid properties (Iffly et al., 1972; Cuiec et al., 1990; Keijzer and De Vries, 1990; Ghedan and Poetmann, 1990; Schechter et al., 1991; Babadagli, 1995; Al-Lawati and Saleh, 1996)low permeability of Chalk reservoir (Torsaeter, 1984; Bourbiaux and Kalaydjian, 1990; Cuiec et al., 1990)wettability (Anderson, 1986; Hirasaki, et al, 1990; Zhou et al., 1995; Buckley, et al , 1995)aging time and temperature and initial water saturations (Zhou et al., 1993; Jadhunandan and Morrow, 1991)scaling of imbibition data (Mattax and Kyte, 1962; Lefebvre du Prey, 1978; Ma, 1995; Zhang et al, 1996)
184/12/2017ObjectivesTo investigate wettability of Spraberry Trend Area at reservoir conditions.To upscale the laboratory imbibition results to field-scale dimensions.To investigate the contribution of the capillary imbibition mechanism to waterflood recovery.To determine the critical water injection rate during dynamic imbibition.
19Fracture Capillary Number 4/12/2017Overview of the StudyDynamicimbibitionStaticimbibitionDetermine rock wettabilityCapillarypressure curveDetermine laboratory critical injection rateFracture Capillary NumberScaling equationsUpscalingUpscalingField dimension
20Outline Laboratory Experiments Static Imbibition Tests 4/12/2017OutlineIntroductionLaboratory ExperimentsStatic Imbibition TestsVerify the effect of P & T on recovery mechanismsDetermine rock wettability indexDynamic Imbibition TestsInvestigate the effect of injection rate on recovery mechanismDetermine critical injection rateModelingConclusionsRecommendations
23Schematic Diagram of the Static Imbibition Process in Laboratory 4/12/2017Schematic Diagram of the Static Imbibition Process in Laboratory138oFImbibition model with one end closed1.5” X ”CorecoreoilSyntheticbrinewaterbeaker
24Experimental Set-up for Imbibition Tests under HPHT 4/12/2017Experimental Set-up for Imbibition Tests under HPHTSide ViewAir BathNVBVBVPRBrine TankHighPressurecoreImbibitionGraduatedCylinderCellBVN2 Bottle(2000 psi)BV = Ball ValveNV = Needle ValvePR = Pressure RegulatorTop ViewInlet for creatingtangential flow
26Effect of Pressure and Temperature on Static Imbibition 4/12/2017Effect of Pressure and Temperature on Static ImbibitionRate and Recovery using Berea Sandstone
27Effect of Temperature on Static Imbibition 4/12/2017Effect of Temperature on Static ImbibitionRate and Recovery using Spraberry Reservoir Rock138oF70oF
28Experimental Procedures for determining WI using Spraberry Cores 4/12/2017Experimental Procedures for determining WI using Spraberry CoresCleaning Spraberry core plugsDean Stark ExtractionChloroform DisplacementDrying (2 days)Evacuated Spraberry brineEvacuation (24 hours)Measure brine density and viscosityWeightSaturation of core samplesIonic equilibrium (3 days)Porosity calculationOil viscosity, density andBrine permeabilityIFT measurementsRecheck the porosityOil floodingEstablish SwiiAging core samples in oilAging time (days)Aging time (days)No aging timeat reservoir temperatureat reservoir temperatureImbibition tests (21 days)Imbibition tests (21 days)Imbibition tests (2 months)at reservoir temperatureat reservoir temperatureat ambient conditionBrine displacementBrine displacementBrine displacementat reservoir temperatureat room temperatureat room temperatureResults
29Amott Wettability Index 4/12/2017Static imbibitionAmott Wettability IndexDisplacementAB1lessmoreWater-wet
304/12/2017Oil Recovery Curves Obtained from Static Imbibition Experiments at Reservoir TemperatureStaticimbibitionASpraberry cores
314/12/2017StaticimbibitionTotal recovery vs aging time shows that 7 days aging time is adequate to start the experimentsDisplacementABSpraberry cores
32Wettability index vs aging time 4/12/2017Static imbibitionWettability index vs aging timefor different experimental temperaturesDisplacementABSpraberry cores
33Dynamic Imbibition Experiments 4/12/2017Dynamic Imbibition ExperimentsSchematic of displacement processExperimental apparatusResults
344/12/2017Schematic Representation of the Displacement Process in Fractured Porous MediumMATRIX BLOCKWaterOil + WaterFRACTUREMATRIX BLOCKOil saturated matrixImbibed waterCapillary imbibitionViscous flowOil produced
364/12/2017Oil Recovery from Fractured Berea Cores during Water Injection using Different Injection Rates
374/12/2017Oil Recovery from Fractured Spraberry Cores during Water Injection using Different Injection RatesUnfractured coreFractured core
38Injection rate versus oil-cut curve for Berea and Spraberry cores 4/12/2017Injection rate versus oil-cut curve for Berea and Spraberry cores
39Outline Modeling Static imbibition data Dynamic imbibition data 4/12/2017IntroductionLaboratory ExperimentsModelingStatic imbibition dataInvestigate Pc from matching of experimental data.Scale up of static imbibition data.Dynamic imbibition dataObtain Pc curves from matching of experimental data.Scale up of dynamic imbibition data.ConclusionsRecommendations
40Modeling of Static Imbibition 4/12/2017Modeling of Static ImbibitionNumerical Analysis of Static Imbibition DataScaling of static imbibition dataResults
41Numerical Analysis of Static Imbibition Data 4/12/2017Numerical Analysis of Static Imbibition DataMatching between Laboratory Experiments and Numerical SolutionCapillary Pressure Curve Obtained as a Result of Matching Experimental data
424/12/2017Scaling of Imbibition Data “Concept of Imbibition Flooding Process” ( Brownscombe, 1952 )InvadedzoneOil production by water imbibitionMatrixWaterOil productionFracturewateroilCapillary forcefracturematrixMatrix fracture fluidexchange mechanismViscous forceTo investigate the contribution of a static imbibition process to waterflood recovery
43Complete Oil Recovery Curves Obtained from Imbibition Experiments 4/12/2017Complete Oil Recovery Curves Obtained from Imbibition ExperimentsSpraberry coresImbibitionANo aging
44Oil Recovery Curves in Terms of Dimensionless Variables 4/12/2017Oil Recovery Curves in Terms of Dimensionless Variables
45Averaging of imbibition curves 4/12/2017Averaging of imbibition curves
46Equations for Scaling of Static Imbibition Data 4/12/2017Equations for Scaling of Static Imbibition Data;C = 10.66
47Rock Properties of Upper Spraberry 1U Unit 4/12/2017Rock Properties of Upper Spraberry 1U Unit
48Recovery Profile 1U Upper Spraberry 1 U Formation (Shackleford-138) 4/12/2017Recovery Profile1Uh = 10 ftLs = 3.79 ftUpper Spraberry1 U Formation(Shackleford-138)
49Effect of Matrix Permeability and Fracture Spacing on Oil Recovery 4/12/2017
50Modeling of Dynamic Imbibition Data 4/12/2017Modeling of Dynamic Imbibition DataNumerical analysis of dynamic imbibition data to obtain capillary curves.Concept of fracture capillary number.Upscaling of dynamic imbibition data to determine critical water injection rate.
51Matching Between Experimental Data and Numerical Solution 4/12/2017Berea CoreMatching Between Experimental Data and Numerical SolutionCumulative water production vs. timeCumulative oil production vs. timeCumulative water production vs. timeSpraberry CoreCumulative oil production vs. time
52Pc Curves Obtained as Result of Matching Experiment Data 4/12/2017Pc Curves Obtained as Result of Matching Experiment DataPc from Numerical Model and Laboratory ExperimentBerea coreSpraberry core
53Fracture Capillary Number 4/12/2017Fracture Capillary NumberLab Units :Viscous force(v w Af )Capillary force( cos Am)whdzAmField Units :Af
54Injection Rate versus Oil-cut 4/12/2017Injection Rate versus Oil-cut
55Dimensionless fracture capillary number versus oil-cut 4/12/2017Dimensionless fracture capillary number versus oil-cut
56Upscaling of Critical Injection Rate 4/12/2017Upscaling of Critical Injection Rate
57O’Daniel Pilot Layout Fracture orientation 4/12/2017 5U (N32E) 10003000200040005000 FEET3161-41561A15149131047282321C36372521291BPROPOSED CO2 INJECTION WELLPROPOSED LOGGING OBSERVATIONWATER INJECTION WELLPLUGGED AND ABANDONEDACTIVE PRODUCERSHUT IN WELL46454741424440393843485U (N32E)5U (N80E)1U (N42E)Fracture orientation
584/12/2017Estimate Critical Water Injection Rates for Wells in O’Daniel Pilot Area
60Conclusions Wettability Determination 4/12/2017ConclusionsWettability DeterminationPerforming the imbibition tests at reservoir temperature and displacement tests at room temperature indicate that WI is 0.3 to 0.4.Performing both imbibition and displacement tests at the same temperature (i.e., reservoir temperature or at room temperature) lowers the WI in the range of 0.20 to 0.25; thus, the temperatures during the experimental sequence affect wettability index determination.Comprehensive experimental data clearly demonstrates that Spraberry reservoir rock is a very weakly water-wet system.
61Conclusions (cont’d) Static Imbibition 4/12/2017Conclusions (cont’d)Static ImbibitionEffect of pressure is much less important than the effect of temperature on imbibition rate and recovery.Performing the imbibition tests at higher temperature results in faster imbibition rate and higher recovery due to change in mobility of fluids, expansion of oil, and change in IFT.The final recovery due to imbibition using Spraberry cores varies from 10% to 15% of IOIP, depending on aging time.
62Conclusions (cont’d) Scaling of static imbibition data 4/12/2017Conclusions (cont’d)Scaling of static imbibition dataThe contribution of the imbibition mechanism to oil recovery is up to 13% IOIP, depending on rock properties and wettability.Degree of heterogeneity in the matrix and natural fracture system controls the efficiency of Spraberry waterflood performance.
63Conclusions (cont’d) Dynamic Imbibition 4/12/2017Conclusions (cont’d)Dynamic ImbibitionAs the flow rate increases, contact time between matrix and fluid in fracture decreases causing less effective capillary imbibition.The capillary pressure curve obtained from dynamic imbibition experiments is higher that of the static imbibition experiments due to viscous forces during the dynamic process.
644/12/2017Conclusions (cont’d)The limiting value of fracture capillary number for an efficient displacement process in this study was found to be and for Berea and Spraberry cores, respectively. Beyond this range, the displacement process is inefficient due to high water-cut.
664/12/2017RecommendationsNecessary to correlate the static and dynamic tests in order to achieve proper upscaling.The capillary pressure curve obtained from dynamic imbibition experiments using artificially fractured core can be used as input data in naturally fractured reservoir simulations instead of using mercury injection capillary pressure curves.
67AcknowledgementI would like to express my sincere appreciation and gratitude to my advisor Dr. David S. Schechter and My committee members Dr. Robert L. Lee, Dr. H.Y. Chen and Dr. Donald Weinkauf for their advice and time spent on this thesis.To PRRC for the financial support through research assistantship grant.To my fellow students and the entire staff of the PRRC for their kindness and assistance.