1、Chemical EOR Progress in China Chemical EOR Progress in China Advances and ChallengesAdvances and ChallengesHarry L.ChangHarrylchangchemortechchemortechchemortechOutline of PresentationOutline of Presentation Overview Recent advancements Chemical EOR in China Polymer flooding ASP flooding Facilities
2、 Some controversial issues and challenges SummaryChemical EOR Global StatusChemical EOR Global Status China has most field experiences US has focused on improvements in chemicals,lab studies,and simulators Increased chemical EOR mechanistic understandings and field activities in US and world-wide in
3、 recent years Harry L.ChangHarry L.ChangGeneral UnderstandingGeneral Understanding Polymer flooding(PF):A mature EOR process Polymer gels:Used successfully in water shut-off and profile modification in selected reservoirs Surfactant-polymer(SP):Effective but expensive ASP:Effective,less expensive,bu
4、t requires extensive treatment of injection/produced fluidsHarry L.ChangHarry L.ChangRecent AdvancementsRecent Advancements Chemicals Laboratory Studies Simulation and Simulators Project Design and Implementation Facilities,Monitoring,and Evaluation More Field ExperiencesHarry L.ChangHarry L.ChangEO
5、R ChemicalsEOR Chemicals Polymers and related chemicals Surfactants Co-surfactants Co-solventsHarry L.ChangHarry L.ChangImprovements on PolymersImprovements on Polymers(UT David Levitt Dissertation)(UT David Levitt Dissertation)Harry L.ChangHarry L.ChangImproved Laboratory TechniquesImproved Laborat
6、ory Techniques Phase behavior/solubalization ratio High temperature and live oil Core flood techniquesHarry L.ChangHarry L.ChangPhase Behavior ExperimentsPhase Behavior Experiments Phase behavior experimentsInexpensive technique for surfactant formulationMeasure solubalization parameters/IFTsMeasure
7、 coalescence/equilibration timeDetermine microemulsion viscosities Specific surfactant(s)can be tailored for specific oilsHarry L.ChangHarry L.ChangAn Excellent ME Phase Behavior An Excellent ME Phase Behavior 0.01.02.00.51.52.53.03.54.0Salinity,%:0.751.251.752.252.75Increasing Electrolyte Concentra
8、tionInterface Fluidity Interface Fluidity High oil recovery90%Sorw,or Sorc 500 ppm.pv now Production of polymer and emulsions may be expected Large scale injection/production facilities are necessary for successful operationsHarry L.ChangHarry L.ChangPolymer Flooding also ShowedPolymer Flooding also
9、 Showed Simplified field operations have been practiced in field-wide operations On-site polymer production would improve the economics KYPAM polymers appears to be more effective in high perm and high salinity reservoirs Visco-elastic behavior can reduce Sor(SPE127453)CDG will enhance PF performanc
10、eHarry L.ChangHarry L.ChangOil Production by Polymer FloodingDaqing Oilfield,China01002003004005006007008009001000199319951997199920012003200520072009YearOil Rate by Polymer Flooding,mmbblsPF Ann.Rate,mmbblsCum.Prod.,mmbblsA Typical PF Field PerformanceA Typical PF Field PerformanceTypical Pressure
11、and Polymer ProductionTypical Pressure and Polymer ProductionOil Production by Polymer FloodingShengli Oilfield,China0204060801001201401601802001997199920012003200520072009YearOil Rate by Polymer Flooding,mmbblsPF Ann.Rate,mmbblsCum.Prod.,mmbblsKYPAM PolymersKYPAM Polymers Comb like with short branc
12、hed chain to maintain effectiveness in high salinity brines Wide MW range for reservoirs with different permeabilities Successfully applied in some reservoirs in China Harry L.ChangHarry L.ChangViscosity Data of KYPAM PolymerViscosity Data of KYPAM PolymerConcentratioConcentration nviscosityviscosit
13、yPerformance of KYPAM PolymersPerformance of KYPAM PolymersPerformance of KYPAM PolymersPerformance of KYPAM PolymersASP Floods in ChinaASP Floods in China Pilot testing:Daqing,Shengli,Karamay Large scale field projects in Daqing Large scale injection/production facilities have been developed in Daq
14、ing Emulsion and scale productions were observedHarry L.ChangHarry L.ChangField ExamplesField Examples Daqing Karamay ASP pilot simulationHarry L.ChangHarry L.ChangASP Pilot Tests Conducted in ASP Pilot Tests Conducted in Daqing OilfieldDaqing OilfieldHarry L.ChangHarry L.ChangASP Results in DaqingA
15、SP Results in Daqing High incremental recovery Severe emulsion production Severe scale production SP with A instead of ASP?One of the most difficult oil for SP floodingHarry L.ChangHarry L.ChangKaramay ASP Pilot Test Design and Karamay ASP Pilot Test Design and Field PerformanceField Performance(SPE
16、 64726)(SPE 64726)Process design/management:Harry Chang Project implementation:Karamay Oilfield A single surfactant system using petroleum sulfonates produced in a local refinery Applied the salinity gradient with STPP for sequestration ASP Pilot Test Well Pattern,ASP Pilot Test Well Pattern,2Z-B9-3
17、 Well Group2Z-B9-3 Well GroupKaramay Oil Field(SPE 64726)Karamay Oil Field(SPE 64726)ASP Slug Design and Injection SequenceASP Slug Design and Injection Sequence(SPE 64726)(SPE 64726)PAMPAMPAMPAMModelling Core Flood-Karamay ASP ProjectModelling Core Flood-Karamay ASP Project Modelling Coreflood Mode
18、lling Coreflood(UTCHEM)(UTCHEM)-Karamay ASP -Karamay ASP Project Project Modelling of Pilot Area Performance(SPE 39610 and 64726)Some Comments on ASPSome Comments on ASP ASP requires special crude oils to improve performances ASP slug cost less but other costs would be substantial(treating injection
19、 brine and produced fluids)Low surfactant concentration(90oC Modeling polymer visco-elastic effects Low MW polymers for low perm.reservoirs Surfactants with low adsorption and other additives Low cost and effective emulsion breakers New scale prevention technologiesHarry L.ChangHarry L.ChangSummaryS
20、ummary A large number and variety of high performance surfactants and polymers are now available for EOR Chemical flooding is now being used for highly viscous crudes,under higher salinity and higher temperature conditions Low cost and more effective lab methods have been developed for chemical form
21、ulations High recovery efficiency(90%OOIP)has been obtained in low permeability sandstone and dolomite reservoir cores The amount of surfactant needed to recovery the oil has been reduced by a factor of 2-5 compared to technology used in 70s and 80s Summary(Contd)Summary(Contd)Polymer flooding has been applied in commercial scales ASP and SP have only been applied successfully in pilot scales Many challenges are still remained in the future in chemical flooding Large resources are available for chemical floodingHarry L.ChangHarry L.ChangTHANK YOU!THANK YOU!
