Wells in gas condensate reservoirs usually exhibit complex behaviours due to condensate deposit as the bottomhole pressure drops below the dew point. The formation of this liquid saturation can lead to a severe loss of well productivity and therefore lower gas recovery. A similar behaviour is observed in volatile oil reservoirs below the bubble point. Understanding these behaviours and extracting values of controlling parameters is necessary to evaluate well potential and design effective programmes to improve productivity.

Our work to-date, in Phases I and II of the JIP, has focused on vertical and horizontal wells in sandstone reservoirs and has led to a better understanding of near-wellbore effects in gas condensate and volatile oil reservoirs from well testing.

Although a large body of knowledge has been acquired through our research in the last seven years, significant challenges remain in the analysis of well tests in gas condensate reservoirs below the dew point pressure, and of well tests in volatile oil reservoirs below the bubble point pressure. These are addressed in the current Phase III of the JIP, which includes:

1. Completing the work initiated during Phase 2
2. Applying deconvolution to the analysis of gas condensate and volatile oil well test data
3. Developing methods for predicting and improving well productivity and evaluating the effectiveness of different remediation solutions