Effect of Dry Gases Injection into Egyptian Gas/Condensate Reservoirs on Condensate Recovery

M. El Aily , S. M. Desouky , M. H. Khalil , A. M. Badawi , O. H. Abdelraheem

Depletion of gas/condensate reservoirs initiates a decline in reservoir pressure below the dew point pressure of the retrograde gas. This leaves valuable amount of condensate in the reservoirs which is not only lost but results in a condensate blockage near the wellbore region and decrease in the productivity. Thus, it is of very essential and economical purposes to find applicable ways to increase the recovery of this lost condensate from the reservoirs. In this study, dry gases are injected into reservoir at initial conditions to delay the dew point pressure that in return enhanced the condensate recovery. This is relying on the fact that the production from gas condensate reservoirs is accompanied by declining in the reservoir pressure. The injection schemes that have been considered are: different injection rates and different reservoir conditions. The study investigated the effect of dry gases injection on 63 samples covers wide ranges of the main parameters of Egyptian gas/condensate reservoirs. Phase behavior, dew point pressure and maximum recovery are studied after and before injection. The study revealed that the dry gas injection into gas/condensate reservoirs minimized the dew point pressure by 18.4% to 23.55% and enhanced condensate recovery by 29.2% to 34.6%.