Gas Condensate Well Deliverability Model, a Field Case Study of a Niger Delta Gas Condensate Reservoir

Abstract

Gas condensate banking accumulated near the wellbore occurs when the bottomhole pressure becomes less than the dew point pressure, allowing the liquid fraction to condense out of the gas phase. Once the accumulation near the wellbore is higher than critical condensate saturation, the liquid phase becomes mobile with the gas phase, affecting well deliverability and making it difficult to estimate gas and condensate flow rate from the reservoir due to two phase flow of fluid. This paper presents an analytical model that evaluates the well deliverability from the reservoir. The concept of two phases Pseudo-pressure is used in the interpretation and evaluation of well deliverability from the gas condensate reservoir. The model considers non-Darcy flow effects and capillary effects. The model is applied to a live field case study of a Niger Delta gas condensate reservoir to determine well deliverability. Gas and liquid production profile from the model showed 95% accuracy when compared with compositional simulation model. This model is encoded into a spreadsheet program using python to calculate well deliverability parameters.