One-third to one-half of the original oil-in-place may remain in a reservoir as it reaches abandonment due to its economic limit. The primary reasons are: heterogeneity of the reservoir, unfavorable fluid properties, and inefficient nature of the displacement process, oil price, and production cost considerations. The secondary reasons, however, are: inappropriate development, inefficient reservoir management practices, and escalating costs of remedial interventions/corrective measures and producing operations. The oil recovery is generally lower than expected due to some combination of the above reasons. Gaining a better understanding of the reservoir fundamentals and the important variables that influence the recovery process can enhance it. This overview course aims to provide such an understanding. It presents the subject material with a clear focus on: developing and producing the reservoir efficiently within its complexity constraints, harnessing energies available within the reservoir-aquifer-injection system, realizing technical benefits and application limitations of the various EOR methods, and selecting the optimum time window. This course covers the recovery improvement possibilities that present themselves at all stages in the reservoir life cycle. It thereby enables one to timely select the most beneficial method and set realistic expectations on production behavior changes and recovery improvement. The impacts of the selected method on personnel training, technology transfer, and facility modification are also covered. The material is presented in simple terms that would enable a participant to understand what works where, what fails when, and why. It is light on theoretical equations, but it scrutinizes these to comprehend importance of significant parameters. It utilizes case studies from projects around the world; their analyses and interpretations aid the participant in understanding of the material. Many illustrative problems, worked in the class by teams, are helpful in gaining a better grasp of the subject matter.

1. Calculate the flow gas wells in gas reservoirs

2. Calculate hydrocarbons initially in place using several methods

3. Assess reservoir performance with dynamic techniques

4. Determine the parameters that impact well/reservoir performance over time

5. Determine reservoir drive mechanisms for gas condensate reservoirs

6. Apply gas field development planning principles

7. The fundamentals of fluid flow in porous media

8. How gas condensate reservoirs are characterized by fluid type and drive mechanisms

9. Gas condensate displacement and optimizing reservoir performance

10. The basics of enhanced gas condensate recovery

11. How gas in place can be estimated and recovery predicted

12. How to apply the material balance techniques

13. How to derive the basic differential equation for radial flow in a porous medium

14.  How these properties affect fluid flow and the distribution of fluids in the reservoir

15. How to perform basic material balance calculations for gas condensate reservoirs

16. How reservoir drive mechanisms affect overall reservoir performance

17. How to use fractional flow theory to calculate displacement efficiency

18. How to measure and calculate gas properties at reservoir conditions

19. How to calculate static pressure and condensate saturations distributions in a reservoir

Reservoir Fluid Types; Gas and Gas Condensate; Representative fluid sample; Molar balance; EOS Fundamentals: Pen-Robinson and Soave-Redlich-Kwong ; K-value correlations;  Phase Envelopes; Estimation of gas condensate reserves; Volumetric Method; Eaton and Jacobi Correlations; Original Gas Condensate in Place (OGCIP); Material Balance; Pressure Declination Method; Retrograde Gas Reservoir; Gas Cycling Process; Gas Injection in a Gas Condensate Reservoir (case study)

This short course provides a basic understanding of gas condensate reservoir and fluid properties. The dry gas injection will yield a modification of the reservoir fluid composition as well as its phase envelope. Fundaments in the estimation of original gas in place using volumetric method, correlations and material balance method.