| dc.contributor.advisor |
Pope , Gary A . |
|
| dc.contributor.committeeMember |
Mohanty , Kishore K . |
|
| dc.creator |
Abbasi Asl , Yousef |
|
| dc.date.accessioned |
2011 -01 -03T18 :42 :26Z |
|
| dc.date.accessioned |
2011 -01 -03T18 :42 :33Z |
|
| dc.date.accessioned |
2011 -08 -16T15 :50 :48Z |
|
| dc.date.available |
2011 -01 -03T18 :42 :26Z |
|
| dc.date.available |
2011 -01 -03T18 :42 :33Z |
|
| dc.date.available |
2011 -08 -16T15 :50 :48Z |
|
| dc.date.created |
2010 -08 |
|
| dc.date.issued |
2011 -01 -03 |
|
| dc.date.submitted |
August 2010 |
|
| dc.identifier.uri |
http : / /hdl .handle .net /2152 /ETD -UT -2010 -08 -1707 |
|
| dc.description.abstract |
Surfactants both change the wettability and lower the interfacial tension by various degrees depending on the type of surfactant and how it interacts with the specific oil . Ultra low IFT means almost zero capillary pressure , which in turn indicates little oil should be produced from capillary imbibition when the surfactant reduces the IFT in naturally fractured oil reservoirs that are mixed -wet or oil -wet .
What is the transport mechanism for the surfactant to get far into the matrix and how does it scale ? Molecular diffusion and capillary pressure are much too slow to explain the experimental data . Recent dynamic laboratory data suggest that the process is faster when a pressure gradient is applied compared to static tests . A mechanistic chemical compositional simulator was used to study the effect of pressure gradient on chemical oil recovery from naturally fractured oil reservoirs for several different chemical processes (polymer , surfactant , surfactant -polymer , alkali -surfactant -polymer flooding ) . The fractures were simulated explicitly by using small gridblocks with fracture properties . Both homogeneous and heterogeneous matrix blocks were simulated . Microemulsion phase behavior and related chemistry and physics were modeled in a manner similar to single porosity reservoirs .
The simulations indicate that even very small pressure gradients (transverse to the flow in the fractures ) are highly significant in terms of the chemical transport into the matrix and that increasing the injected fluid viscosity greatly improves the oil recovery . Field scale simulations show that the transverse pressure gradients promote transport of the surfactant into the matrix at a feasible rate even when there is a high contrast between the permeability of the fractures and the matrix . These simulations indicate that injecting a chemical solution that is viscous (because of polymer or foam or microemulsion ) and lowers the IFT as well as alters the wettability from mixed -wet to water -wet , produces more oil and produces it faster than static chemical processes . These findings have significant implications for enhanced oil recovery from naturally fractured oil reservoirs and how these processes should be optimized and scaled up from the laboratory to the field . |
|
| dc.format.mimetype |
application /pdf |
|
| dc.language.iso |
eng |
|
| dc.subject |
Wettability |
|
| dc.subject |
IFT |
|
| dc.subject |
Simulation |
|
| dc.subject |
Imbibition |
|
| dc.subject |
Fractured |
|
| dc.subject |
Oil -wet |
|
| dc.subject |
Mixed -wet |
|
| dc.subject |
Water -wet |
|
| dc.subject |
Interfacial tension |
|
| dc.subject |
UTCHEM |
|
| dc.subject |
Capillary |
|
| dc.subject |
Gravity |
|
| dc.subject |
Microemulsion |
|
| dc.subject |
Surfactant |
|
| dc.subject |
Alkali |
|
| dc.subject |
Polymer |
|
| dc.subject |
Recovery |
|
| dc.title |
Simulation study of surfactant transport mechanisms in naturally fractured reservoirs |
|
| dc.description.department |
Petroleum and Geosystems Engineering |
|
| dc.type.genre |
thesis |
* |
| dc.type.material |
text |
* |
| thesis.degree.name |
Master of Science in Engineering |
|
| thesis.degree.level |
Masters |
|
| thesis.degree.discipline |
Petroleum Engineering |
|
| thesis.degree.grantor |
University of Texas at Austin |
|
| thesis.degree.department |
Petroleum and Geosystems Engineering |
|
| dc.date.updated |
2011 -01 -03T18 :42 :33Z |
|