Optimal Design of Two- and Three- Phase Separators: A Mathematical Programming Formulation

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractOilfield primary separator units are subject to nonlinear fluid dynamic and mechanical constraints. Their design represents a challenging and important problem. In this paper we present separator design problems for which the lowest cost, optimal, solution is found using sequential quadratic programming techniques. The optimization models utilize existing separator design theories and relationships. They consist of a declarative set of equations and inequalities that is independent of the solution method and hence it is easy to make modifications and the assumptions are clear. The models are outlined and discussed in the context of horizontal separators. The efficiency and effectiveness of the suggested systematic design method are exemplified by two illustrative design cases. Process Unit Design and Mathematical ProgrammingAlgorithmic mathematical optimization techniques have been used extensively in systematic methods for chemical process design. Mathematical programming formulations are used for SPE 56645

Mathematical Modeling of the Destabilization of Crude Oil Emulsions Using Population Balance Equation

“…1,4 On the other hand, theoretical studies based on the joint use of mass balance and Stokes law have been proposed in the literature to simulate the destabilization of petroleum emulsions or to design separation vessels. 4,6 In fact, the main phenomenon taken into account in these models is the droplet settling, which can be easily probed by experimental measurements of average droplet sizes and concerning the demulsification process can be obtained by either "bottle tests" or mass balance combined with Stokes law, much work remains to be done in terms of generating robust mathematical descriptions of the water-in-crude oil destabilization process.…”

“…For instance, “bottle tests” provide a means for estimating ranges of treating temperature and retention time for design purposes. However, these tests are static in nature and do not model closely the dynamic effects of dispersed water droplets and the coalescence that occur during actual flow of crude oil emulsions. , On the other hand, theoretical studies based on the joint use of mass balance and Stokes law have been proposed in the literature to simulate the destabilization of petroleum emulsions or to design separation vessels. , In fact, the main phenomenon taken into account in these models is the droplet settling, which can be easily probed by experimental measurements of average droplet sizes and retention times. Despite interesting pieces of information concerning the demulsification process can be obtained by either “bottle tests” or mass balance combined with Stokes law, much work remains to be done in terms of generating robust mathematical descriptions of the water-in-crude oil destabilization process.…”

Computational and Experimental Investigation of using an Extractor in the Vertical Gravitational Flash Tank Separator

“…For example, the liquid separation efficiency becomes higher than 45% when the flow pattern at the inlet is annular, while the liquid separation efficiency becomes higher than 80% for slug flow at 6708 low liquid superficial velocity, but the liquid separation efficiency becomes essentially 100 % for stratified flow [8]. Refrigerant R134A has been used widely to investigate the separation efficiency in a vertical separator by several researchers including Hanfei and Hrnjak [3] and Zheng, Zhao [9], while others, notably Wang [7] and Grodal and Realff [10] used different configurations of the vertical separator. Critical droplet size technique can also be considered as a way to assess the separation efficiency, which is based on the terminal velocity.…”