This paper examines and compares Natural and Artificial Gas Lift performance of one of the Iranian Offshore fields.Before the results of this study,gas channeling from the upper gas layer,a phenomenon which causes gas streams to pierce into some of the wellbores,was characterized as a negative effect which should be treated or repaired.On the other hand,regarding that this is a fractured under-saturated reservoir with an active aquifer mechanism,it was foreseen that applying immiscible gas and water injection in this reservoir in order to increase recovery factor are ineffective;and studies supported this idea.With respect to the growing amount of water production,need to further study Artificial Lift Methods was assumed essential.Considering operational conditions and abundance of excessive gas in this field,a gas lift system was designed and the optimum injection points with best recoveries were identified.However,reservoir simulation surprisingly demonstrated that when gas channeling from the upper gas layer is taken into account,oil production rates exhibit a significant increase.This could be interpreted as Natural Gas Lift.In this paper,we indicate how accidental gas channeling in the wells of this reservoir has prompted oil production rate to raise.Results of well modeling by PROSPER software,considering different flow scenarios,were imported into reservoir simulator and final recoveries were observed during a certain time period.Conclusively,it is suggested that controlling gas channeling in these wells by employing Natural Gas Lift Technology would maintain oil production capacity.According to the results,total field oil recovery factor would be almost 4 percent more than natural depletion during 21 years and that would be the most economical,applicable and effective way to improve recovery factor in this reservoir.
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