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dc.contributor.advisorGu, Yongan
dc.contributor.authorCao, Meng
dc.date.accessioned2013-10-30T18:46:01Z
dc.date.available2013-10-30T18:46:01Z
dc.date.issued2012-12-17
dc.identifier.urihttp://hdl.handle.net/10294/3787
dc.descriptionA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Petroleum Systems Engineering, University of Regina. xviii, 124 l.en_US
dc.description.abstractIn this thesis, the mutual interactions between a light crude oil and CO2 at the reservoir temperature were experimentally studied. The oil recovery mechanisms and asphaltene precipitation phenomenon in tight sandstone reservoir core plugs during immiscible and miscible CO2 flooding processes were examined. Meanwhile, the physicochemical properties of the produced oils and gases during CO2 flooding processes were thoroughly characterized. Furthermore, numerical simulation was performed to history match the experimental oil production data for the miscible CO2 coreflood tests. In experiment, first, a visualized saturation cell was used to determine the onset pressure of the asphaltene precipitation (Pasp). Second, the vanishing interfacial tension (VIT) technique was applied to determine the minimum miscibility pressure (MMP) and the so-called first-contact miscibility pressure (Pmax) between the original light crude oil and CO2. Meanwhile, the oil-swelling effect and initial quick light-hydrocarbons extraction were observed during the interfacial tension (IFT) measurements. The onset pressure of the initial quick light-hydrocarbons extraction (Pext) was determined. Third, the oil-swelling factor, CO2 solubility in the crude oil, and the saturation pressure of the light crude oil–CO2 system were measured by using a PVT cell. Then a total of five CO2 coreflood tests, which represented the immiscible, near-miscible, and miscible flooding processes, were performed at the reservoir temperature. In the simulation work, an equation of state (EOS) model was built and tuned by using the CMG WinProp module. A 1-D model was generated by using the CMG GEM module to simulate the CO2 coreflood tests. History matching was undertaken by using the CMG CMOST module to match the measured cumulative oil production in the miscible CO2 flooding processes. The experimental results showed that the measured four important onset pressures of the light crude oil–CO2 system at the reservoir temperature were in the order of Pasp < Pext < MMP < Pmax. The MMP was determined to be 10.6 MPa by applying the VIT technique. In addition, the four onset pressures increased as the temperature increased. Also, it was found that the temperature had a less effect on the oil-swelling factor than on the saturation pressure. The CO2 coreflood test data showed that the oil recovery factor (RF) increased monotonically as the injection pressure increased during the immiscible CO2 flooding process. Once the injection pressure exceeded the MMP, the oil RF increased slightly and then reached an almost constant maximum value. Moreover, the oil RF after CO2 breakthrough (BT) increased slightly under the immiscible conditions but substantially in the miscible case. On the other hand, the measured average asphaltene content of the produced oil and the measured oil effective permeability reduction were found to be higher in the immiscible flooding process. They both reached some lower values in the miscible case. Furthermore, at a lower injection pressure, the produced oil became heavier and heavier during CO2 injection process in terms of its density, viscosity, molecular weight, and hydrocarbons (HCs). The produced gas contained up to 84–96 mol.% HCs extracted from the light crude oil by CO2 at the beginning. At a higher injection pressure, the produced oil became much lighter and lighter with the pore volume of injected CO2 and the produced gas contained 20–75 mol.% HCs at the very beginning. Besides, the total oil RF was much higher at a higher temperature under the miscible conditions. Lastly, a good agreement was found between the simulated and measured oil production data in the miscible CO2 flooding processes.en_US
dc.language.isoenen_US
dc.publisherFaculty of Graduate Studies and Research, University of Reginaen_US
dc.subject.lcshOil field flooding
dc.subject.lcshSecondary recovery of oil
dc.subject.lcshAsphaltene
dc.subject.lcshCarbon dioxide
dc.titleOil Recovery Mechanisms and Asphaltene Precipitation Phenomenon in CO2 Flooding Processesen_US
dc.typeThesisen
dc.description.authorstatusStudenten
dc.description.peerreviewyesen
thesis.degree.nameMaster of Applied Science (MASc)en_US
thesis.degree.levelMaster'sen
thesis.degree.disciplineEngineering - Petroleum Systemsen_US
thesis.degree.grantorUniversity of Reginaen
thesis.degree.departmentFaculty of Engineering and Applied Scienceen_US
dc.contributor.committeememberTorabi, Farshid
dc.contributor.committeememberJin, Yee-Chung
dc.contributor.externalexaminerVeawab, Amornvadee
dc.identifier.tcnumberTC-SRU-3787
dc.identifier.thesisurlhttp://ourspace.uregina.ca/bitstream/handle/10294/3787/Cao_Meng_200302542_MASc_PSE_Spring2013.pdf


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