A novel three pseudo-component approach (ThPCA) for thermodynamic description of hydrocarbon-water systems

Mehrak Mahmudi,Mohammad Taghi Sadeghi

doi:10.1007/s13202-013-0072-z

Abstract

Thermodynamic description of the hydrocarbon processes facing considerable variation in composition such as gas-lift process require an accurate and speedy algorithm to perform the three-phase multi-component flash calculation based on an equation of state. A novel approach for thermodynamic description of the three-phase fluid is introduced in this study to overcome the complex and time-consuming multi-component flash calculation procedure. The constituents of each pseudo-component and their properties were determined employing an optimization method minimizing the difference between the results of the three pseudo-component approach (ThPCA) with those from the compositional approach. Performance results both in accuracy and computing speed for the ThPCA method showed that using the three optimum pseudo-components with flash calculations based on an equation of state, reduce the computational time by half compared to the compositional model while it only decreases the accuracy by 5 %.

Highlights

List of symbols f Fugacity G Vapor phase fractionHydrocarbon-water fluid systems consist of different components including hydrocarbons and water distributed in the three phases of water-rich liquid, hydrocarbon-rich liquid and vapor
Performance results both in accuracy and computing speed for the three pseudo-component approach (ThPCA) method showed that using the three optimum pseudo-components with flash calculations based on an equation of state, reduce the computational time by half compared to the compositional model while it only decreases the accuracy by 5 %
An illustrative example based on a mature Iranian oil field was used to evaluate the three pseudo-component approach

Summary

Introduction

List of symbols f Fugacity G Vapor phase fractionHydrocarbon-water fluid systems consist of different components including hydrocarbons and water distributed in the three phases of water-rich liquid, hydrocarbon-rich liquid and vapor. Performance results both in accuracy and computing speed for the ThPCA method showed that using the three optimum pseudo-components with flash calculations based on an equation of state, reduce the computational time by half compared to the compositional model while it only decreases the accuracy by 5 %.

Objectives

Results

Conclusion