Analysis of Transport Mechanisms in Gas Condensate Reservoirs

The study of depletion performance of gas condensate reservoirs has gained wide interest in petroleum industry during the last few decades and poses a challenge for the reservoir modeler. Upon depletion, reservoir pressure may fall below the dew-point of hydrocarbon mixture which results in liquid condensation at reservoir conditions. The condensation presence will hinder the flow of hydrocarbons and severely obstruct their recovery. This becomes highly noticeable for the case of tight reservoirs (less than 10 md). Hence, it is critical to answer this question whether this trapped gas has been irreversibly lost or not. It is believed that the interplay of Darcian-type flow and Fickian type flow (multimechanistic flow) is the key to answering this question. In this work, we show the dominant flow processes and recovery mechanisms taking place in gas-condensate reservoirs and describe the depletion performance of these systems, which provides guidance for the development and analysis of this class of reservoirs.

Keywords:

Diffusion , Fickian flow , Darcian flow , condensate