Dynamics, Aggregation, and Interfacial Properties of the Partially Hydrolyzed Polyacrylamide Polymer for Enhanced Oil Recovery Applications: Insights from Molecular Dynamics Simulations

Peptides and their derivatives can be applied in enhanced oil recovery (EOR) due to their ability to form an emulsion with hydrophobic molecules. However, peptide research for EOR application, either theoretical or computational studies, is still limited. The purpose of this research is to analyse the potency of the X6D model of surfactant peptide for EOR by molecular dynamics simulations in oil-water interface. Molecular dynamics simulation using GROMACS Software with Martini force field can assess a peptides ability for self-assembly and emulsification on a microscopic scale. Molecular dynamics simulations combined with coarse grained models will give information about the dynamics of peptide molecules in oil-water interface and the calculation of interfacial tension value. Four designs of X6D model: F6D, L6D, V6D, and I6D are simulated on the oil-water interface. The value of interfacial tension from simulation show the trend of F6D L6D I6D V6D. The results indicate that V6D has the greatest reduction in interfacial tension and has the stability until 90C with the salinity of at least 1M NaCl.

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Molecular dynamics simulations of interfacial properties of the CO2–water and CO2–CH4–water systems

The Journal of Chemical Physics ◽

10.1063/5.0008114 ◽

2020 ◽

Vol 153 (4) ◽

pp. 044701

Author(s):

Parisa Naeiji ◽

Tom K. Woo ◽

Saman Alavi ◽

Ryo Ohmura

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Interfacial Properties ◽

Water Systems ◽

Dynamics Simulations

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Temperature Dependence of the Shear-Thinning Behavior o Partially Hydrolyzed Polyacrylamide Solution for Enhanced Oil Recovery

Journal of Energy Resources Technology ◽

10.1115/1.4048592 ◽

2020 ◽

Vol 143 (6) ◽

Author(s):

Pan-Sang Kang ◽

Jong-Se Lim ◽

Chun Huh

Keyword(s):

Temperature Dependence ◽

Polymer Solution ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Polymer Concentration ◽

Shear Thinning ◽

Temperature Model ◽

Polyacrylamide Solution ◽

Partially Hydrolyzed Polyacrylamide ◽

Hydrolyzed Polyacrylamide

Abstract The viscosity of injection fluid is a critical parameter that should be considered for the design and evaluation of polymer flood, which is an effective and popular technique for enhanced oil recovery (EOR). It is known that the shear-thinning behavior of EOR polymer solutions is affected by temperature. In this study, temperature dependence (25–70 °C) of the viscosity of a partially hydrolyzed polyacrylamide solution, the most widely used EOR polymer for oil field applications, was measured under varying conditions of the polymer solution (polymer concentration: 500–3000 ppm, NaCl salinity: 1000–10,000 ppm). Under all conditions of the polymer solution, it was observed that the viscosity decreases with increasing temperature. The degree of temperature dependence, however, varies with the conditions of the polymer solution. Martin model and Lee correlations were used to estimate the dependence of the viscosity of the polymer solution on the polymer concentration and salinity. In this study, we proposed a new empirical model to better elucidate the temperature dependence of intrinsic viscosity. Analysis of the measured viscosities shows that the accuracy of the proposed temperature model is higher than that of the existing temperature model.

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A Molecular Dynamics Study of Soaking During Enhanced Oil Recovery in Shale Organic Pores

SPE Journal ◽

10.2118/199879-pa ◽

2020 ◽

Vol 25 (02) ◽

pp. 832-841 ◽

Cited By ~ 1

Author(s):

Felipe Perez ◽

Deepak Devegowda

Keyword(s):

Molecular Dynamics ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Volatile Oil ◽

Pore Network ◽

Fluid Mixture ◽

Soaking Time ◽

Diffusive Flow ◽

Dynamics Simulations

Summary In this work we use molecular dynamics simulations to investigate the interactions during soaking time between an organic solvent (pure ethane) initially in a microfracture and a mixture of hydrocarbons representative of a volatile oil, and other reservoir fluids such as carbon dioxide and water, originally saturating an organic pore network with a predominant pore size of 2.5 nm. We present evidence of the in-situ fractionation in liquid-rich shales and its implications in enhanced oil recovery (EOR) projects. We also discuss the behavior of the larger and heavier molecules in the fluid mixture while the solvent interacts with them. Notably, prior to solvent invasion of the pores and further mixing with the reservoir fluids, the heavier hydrocarbons in the mixture are initially adsorbed onto the pore surface and pore throats surface, partially clogging them. We show that the porous structure of kerogen and the presence of adsorbed molecules of asphaltenes and resins in the pore throats act as a molecular sieve and may be one of the reasons for the fractionation of the reservoir fluids. The differing ability of the solvent to desorb and mix with different hydrocarbon species is another reason for the fractionation occurring during soaking. Our simulations show that the production of reservoir fluids occurs due to a countercurrent diffusive flow from the organic pore network to the microfracture driven by the concentration gradient between the two regions.

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