ABSTRACT: The presence of asphaltene at both fluid−fluid and
fluid−solid interfaces has a wide impact on petroleum recovery
processes, for example, by stabilizing oil−gas−water dispersions,
adsorbing on reservoir rock surfaces and thus changing their
wetting properties, and forming deposits in oil−gas production
systems. The Yen-Mullins model for asphaltene behavior in bulk
fluids provides a framework for understanding a diverse range of
phenomena related to the adsorption dynamics of asphaltene at
interfaces and how the adsorbed layers are structured. In this work,
we address the relatively less explored parameter, which is
accounting for the size and shape of the particles on the interfacial
properties and emulsion stability. We discuss our investigations of
the asphaltene adsorption and its effects, focusing on oil−water
interfaces, and propose a lattice-gas model to explain the experimental observations of the interfacial tension and rheology.
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Interfacial CO 2 -mediated nanoscale oil transport: from impediment to enhancement
CO 2 -based enhanced oil recovery is widely practiced. The current understanding of its mechanisms largely focuses on bulk phenomena such as achieving miscibility or reducing oil density and viscosity. Using molecular dynamics simulations, we show that CO 2 adsorption on calcite surfaces impedes decane transport at moderate adsorption density but enhances decane transport when CO 2 adsorption approaches surface saturation. These effects change the decane permeability through 8 nm-wide pores by up to 30% and become negligible only in pores wider than several tens of nanometers. The strongly nonlinear, non-monotonic dependence of decane permeability on CO 2 adsorption is traced to CO 2 's modulation of interfacial structure of long-chain hydrocarbons, and thus the slippage between interfacial hydrocarbon layers and between interfacial CO 2 and hydrocarbon layers. These results highlight a new and critical role of CO 2 -induced interfacial effects in influencing oil recovery from unconventional reservoirs, whose porosity is dominated by nanopores.
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- Award ID(s):
- 1705287
- NSF-PAR ID:
- 10279664
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 22
- Issue:
- 40
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 23057 to 23063
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D0CP03930F
