Evaluating Constant-Volume Depletion Data

This paper presents methods for evaluating constant volume depletion (CVD) data obtained from experimental analyses of gas condensates and volatile oils. Theoretical and practical developments are supported by experimental data from a North Sea gas-condensate fluid. The three major contributions of the work are: presentation of material-balance equations to calculate fluid properties from measured CVD data; a simple method for calculating black-oil formation volume factors and solution GOR's using material-balance results and a separator flash program; and investigation of the Peng-Robinson (PR) equation of state (EOS) as a tool for matching measured PVT data and studying vapor/liquid phase behavior during CVD.