Evaluating Constant-Volume Depletion Data

Abstract

This paper presents methods for evaluating constantvolume 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: (1) presentation of material-balance equations to calculate fluid properties from measured CVD data, (2) a simple method for calculating black-oil formation volume factors and solution GOR's using material-balance results and a separator flash program, and (3) investigation of the Peng-Robinson (PR) equation of state (EOS) as a tool for matching measured PVT data and studying vaporlliquid phase behavior during CVD.• Now with Esso E&P Norway Inc.

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Efficient methods for calculations of compressibility, density and viscosity of natural gases

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