Near-critical gas/condensate relative permeability of carbonates

Calisgan, H.
Demiral, B.
Akın, Serhat
The productivity of most gas condensate wells is reduced significantly due to condensate banking when the bottom-hole pressure falls below the dew point. The liquid drop-out such gas wells leads to reduced gas relative permeability and thus to low recovery problems. An understanding of the characteristics of the high-velocity gas-condensate flow and relative permeabilities is necessary for accurate forecast of well productivity. In order to tackle this goal, a series of relative permeability measurements on a moderate permeability carbonate core, using a binary retrograde condensate fluid sample were conducted near miscible conditions. The experiments used a pseudo-steady-state technique at high pressure and high velocity, measuring relative permeability under conditions similar to the near well region of a carbonate gas-condensate reservoir. Furthermore, the flow of gas and condensate at different force ratios (capillary and bond numbers) are investigated. It was observed that relative permeability depended on fluid composition and flow rate as well as condensate and water saturations. It was observed that as the flow rate of wetting phase (condensate) increased or the interfacial tension decreased, relative permeability curves shifted to left. It was found that a simple three-parameter mathematical model that depends on a new dimensionless number called condensate number successfully models the gas-condensate relative permeability data. The developed model resulted in a good agreement with published gas-condensate relative permeability data as well as end point relative permeabilities and saturations.
Citation Formats
H. Calisgan, B. Demiral, and S. Akın, “Near-critical gas/condensate relative permeability of carbonates,” 2006, vol. 1, Accessed: 00, 2021. [Online]. Available: