Assessing the Validity of Equilibrium Contact Mixing Method in Synthesizing Original Fluid of Gas Condensate Reservoirs

Authors

1 IOR Research Institute, National Iranian Oil Company

2 Research & Technology Directorate National Iran Oil Company

Abstract

The significance of preparing representative reservoir fluids in optimizing reservoir management is clearly obvious for experts, and it has always been tried to prepare a representative fluid at the early life of reservoir by standard methods. This will lead to the reduction of inaccuracy and causes an appropriate prediction of phase and flow behavior of reservoir. Methods of preparing an original reservoir fluid are mentioned in various standards like API-RP44 in details. These methods are on the basis of stabilizing reservoir and sampling conditions. In 1994, Fevang and Whitson presented a new method titled equilibrium contact mixing (ECM). They claimed that this method was operational for gas condensate reservoirs in any conditions. Their method reversed the dominant standards of sampling and had no time limitation in preparing representative fluid from the collected samples. This paper examines ECM techniques and checks the verity of this method in various conditions. For this purpose, a synthetic model consists of lean and rich gas condensate reservoirs in saturated and under saturated conditions and surface separator facilities are constructed. After production and sampling from models, ECM and recombination techniques are simulated and used for synthesizing original fluids from the collected samples. Evaluating the methods of synthesizing original reservoir fluids states that the new and non-familiar ECM techniques are remarkably more accurate than the conventional recombination method in any conditions, particularly in a depleted situation. The accurate obtained results suggest proposing this method to petroleum companies.
 

Keywords


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