Influence of Interfacial Tension on Gas/Oil Relative Permeability in a Gas-Condensate System

Abstract

To understand better the effect of interfacial tensions (1FT's) on gas/oil relative permeabilities, with particular emphasis on those effective in condensate reservoirs, an experimental procedure was developed and used with the highly volatile methane/propane system. The objective was to measure steady-state relative permeabilities as functions of 1FT. Thus the 1FT was varied from 0.03 to 0.82 dynes/cm [0.03 to 0.82 mN/m], corresponding to pressures near the critical at a constant temperature of 70 D F [21 DC].Individual relative permeability curves obtained as a function of gas saturation approach the 45 D [0.79-rad] diagonals for both gas and oil as the 1FT is lowered. This supports the expectation that relative permeability curves for both gas and oil become straight lines as the 1FT approaches zero. At the highest 1FT for which experiments were performed (0.82 dynes/cm [0.82 mN/m]), the relative permeability curves approached those obtained for a nitrogen/kerosene flood for which the 1FT is approximately 30 dynes/cm [30 mN/m].The most important conclusions derived from this work are that (I) the curvatures of the relative permeability curves diminish as the 1FT is reduced, (2) the irreducible gas and liquid saturations approach zero as the 1FT approaches zero, and (3) relative gas/oil permeabilities for gas-condensate reservoirs are altered from the normal relative permeabilities only at pressures, temperatures, and compositions close to the critical point.

Surfactant-Polymer Coreflood Simulation and Uncertainty Analysis Derived from Laboratory Study

“…IFT reduction will alter the relative permeability and influences each phase flow behavior [10][11][12][13][14]. In a numerical study on chemical injection it was observed that the relative permeability curve can be represented by 4 curves that are obtained from measurements and show 2 extreme and 2 transition conditions ( Figure 1) [9].…”

Critical Condensate Saturation in Porous Media

“…The maximum length for flow, h max , is directly proportional to interfacial tension from Eq. [3]. But the saturation needed to make a cluster of length h max is not linear with h max .…”

Three-dimensional and two-phase numerical simulation of fractured dry gas reservoirs

“…An equation for determination fracture network permeability was developed . Effect of surface tension on gas and condensate relative permeability was investigated (Asar and Handy 1988). A gas condensate reservoir including a mixture of three hydrocarbons with compositional and fully implicit method was modeled (Jones and Raghavan 1988).…”