Prediction of Optimum Separation Conditions for Sequential Field Separation System

Abstract

A study has been done for finding the optimum separators pressures of degassing station .The optimum operation pressures are determined by employing Constrained Rosenbrock (1966) method using the maximum API, minimum GOR and minimum Bob as objective functions and separators pressures as the decision variables. The optimization of separators pressures requires equilibrium flash calculation under different conditions of pressures and temperatures to determine the conditions that will yield the most stock tank liquid. Equilibrium flash calculation is achieved by solving the equation of state. In the current study, Soave-Redlich-Kwong(1972)and Peng-Robinson (1976) have been used wit the black and volatile oils respectively.Two computer models are used to find the optimum separators pressures .The first model is OSPB which can be used with black oils while the second is OSPV that employs volatile oils. Application of these models shows improvement of the all objective functions for oils. Two checking techniques (the plotting &sensitivity analysis test) proved the validity of these optimization models.