Mixing During Two-Phase, Steady-State Laboratory Displacements in Sandstone Cores

Abstract

were linear functions of velocity at any given saturation.Brine dispersion coefficients were This paper examines the changes in fluid distriindistinguishable from those obtained in stable, butions and the mixing that occurs in immiscible single-phase diap?ncementa on the same cG.e. Oil phases flowing in a porous medium with changes in phase dispersion coefficients were, in general, phase saturations and flow rates. We report experi-greater than those for the brine phase, but decreased mental results for steady-state displacements with as oil saturation increased, and at low water saturations established by secondary drainage, for one saturation were the same or less than those for the outcrop and one reservoir sandstone. Displacements brine phase. Mass transfer coefficients were also were performed using immiscible liquids of matched linear functions of displacement velocity and had density and viscosity at six saturatio!:sranging from similar values for both phases. residual oil to low initial water saturation. Flow rates at a given saturation were usual:.yvaried by The differences in displacement resulta between more t' n an order of magnitude.the two core samples are interpreted in terms of pore structure and changes in fluid distribution with Trapped, dendritic and flowing fractions were changes in saturation and flow rate. Finally, we determined for each phase by fitting effluent composidiscuss the implications of the mixing results for tion data to the Coats-Smith model as modified by the performance of EOR processes. Salter and Hohanty.The oil phase and, contrary to previous investigations, the brine phase both exhibited trapped saturations.

Numerical Simulation of Pore-Scale Fluid Mobilization during Immiscible Displacement

“…The dead-end pores contribute about 34%−51% of the pore space of the reservoir rocks, which causes significant oil trapping in these pore constrictions. 41 A heterogeneous porous medium geometry is taken from Keller et al, 39 and a fracture has been created horizontally in the middle of the porous medium to understand the severity of oil trapping. The total void space present in the porous medium is 1.18 × 10 −7 m 2 .…”

Dispersion measurement as a method of quantifying geologic characterization and defining reservoir heterogeneity. Final report

“…The effect of the absolute value of viscosity is neglected. Shown in Figs.5.4.7 and 5.4.8 are effluent concentration profiles for Berea and Rock Creek sandstones, respectively, given by Bretz et al 34. On the left side of each figure is the water phase dispersion curve, and on the right side is the oil phase dispersion curve.…”

Influences of Dead‐End Pores in Porous Media on Viscous Fingering Instabilities and Cleanup of NAPLs in Miscible Displacements

“…Using this model, Bretz et al. (1986) and Bretz and Orr (1987) found that the fraction of dead‐end pores in porous media can be up to 34%, 42%, and 51% for certain Berea sandstone, Rock Creek sandstone, and San Andres carbonate rocks, respectively. Later, similar models were developed for both miscible and immiscible displacements at different scenarios (Babaei & Islam, 2020; Bai et al., 1995; Karadimitriou et al., 2016; Piquemal, 1993; Salter & Mohanty, 1982; van Genuchten & Wierenga, 1976).…”