Simulation of Surface Light Hydrocarbon Recovery Process in the Compositional Simulation

Abstract

SPE Member Abstract This paper describes phase behavior simulation of complex process station in the light and volatile oil reservoir simulation, using equation of state method. The technology process of the station includes two-stage separation, crude oil stabilization, three-phase separation, shallow cooling, deethanization and debutanization. In the new compositional model, the simulation of surface complex process station is considered with combination of reservoir simulation based on uniform parameters of equation of state. The differential flash method and nested successive substitute iteration method have be used for solving dynamic phase equilibrium problem for deethanizer and debutanizer in the simulator. The simulator also considered process and product quality controls. The simulator provides calculation results for production of stabilized oil sale dry gas, light oil, naphtha and LPG. It is very useful for light oil and volatile oil reservoir simulation. Introduction The compositional model is commonly used for light oil, volatile oil and gas condensate reservoir simulations, but conventional compositional simulators simulate surface facilities limited within multiple stage separation. In the development of light oil and volatile oil reservoirs in China, the complex process stations are used to be built for oil-gas separation and light hydrocarbon recovery process. Therefore it is necessary to develop a new kind of compositional model involving complex process station simulation. There are two approaches for solving that kind of problem. One way is simultaneous simulation of surface facility and reservoir flow behavior in the same simulator. Another way is developing all independent surface facility simulator and using interface file to connect surface facility simulation with reservoir simulation. Easy way is last one, and we have accepted it. Although surface facility simulator is written as independent one, the programming inside configuration of the program and all called routines are conformed with main compositional reservoir simulator. We can look the new compositional model as a model consisted of three parts: initialization program, main model and surface facility simulator, which connected each other with interface files. P. 209