عنوان

Multi-scale Systematic Surfactant Structure-Performance Studies in Tight Carbonate Reservoirs and at High Temperature and Salinity Conditions

Number

TLpq2311653040

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Multi-scale Systematic Surfactant Structure-Performance Studies in Tight Carbonate Reservoirs and at High Temperature and Salinity Conditions

General Material Designation

[Thesis]

First Statement of Responsibility

Olawale, Opeoluwa W.

Subsequent Statement of Responsibility

Piri, Mohammad

Name of Publisher, Distributor, etc.

University of Wyoming

Date of Publication, Distribution, etc.

2019

Specific Material Designation and Extent of Item

162

Dissertation or thesis details and type of degree

M.S.

Body granting the degree

University of Wyoming

Text preceding or following the note

2019

Text of Note

In tight carbonate reservoirs, the full potential for enhanced oil recovery (EOR) offered by surfactant flooding remains underutilized. The main challenge is that it is not yet possible to determine a priori the optimal surfactant to deploy, and empirical testing of different surfactant formulations is prohibitively costly. The objective of the presented research is to tackle this challenge by developing a predictive correlation between the surfactant molecular properties and their effectiveness as the EOR agents. To attain this objective, we tested the hypothesis that oil recovery enhancement by surfactants in fractured tight carbonate reservoirs is dependent on the adsorption mechanism of the surfactant to the carbonate surface. The adsorption, in turn, depends on the surfactant molecular structure and the electrochemical interactions within the rock/brine/oil system. The results confirm that cationic surfactants with different tail lengths exhibit different levels of adsorption, despite the same head group, underscoring the importance of hydrophobic interactions. We found that in tight carbonate reservoirs, adsorption is inversely correlated with the recovery enhancement by surfactants. However, cationic surfactants yield very low oil recovery in tight oil-wet carbonate reservoirs or at high salinity despite having low adsorption compared to the other surfactant types. By contrast, nonionic surfactants with low adsorption and high emulsifying tendencies appear to be most effective for enhancing matrix access in these systems. Finally, the equilibrium adsorption levels of polyoxyethylenated nonionic surfactants were shown to be inversely correlated with the newly defined structural parameter - the ratio of the ethylene oxide count to approximate tail carbon number (EO:TCN).

Chemical engineering

Energy

Petroleum engineering

Olawale, Opeoluwa W.

Piri, Mohammad

Electronic name

p

[Thesis]

276903

a

Y