Estudo paramétrico do processo de extração com solvente (VAPEX) como método de recuperação de óleo pesado

Abstract

There is still a large amount of natural resources in heavy oil reservoirs which can be explored using new methods. The world estimate of resources as heavy oil and bitumen may be 6 trillion barrels of oil in place. However, this enormous amount of hydrocarbon resources which are in these reservoirs may be explored with new concepts. The VAPEX process is a promising recovery method since its invention in 1991 by Dr. Roger Butler. The process consists in two horizontal wells, parallel between themselves, producer and injector, where vaporized solvent is injected with the objective of reducing the oil or bitumen viscosity. The purpose of this study is to examine how some important operational and of reservoir parameters influence the VAPEX process, in the produced oil rates, in the cumulative produced oil and in the recovery factor. Parameters such as the spacing between wells, the injection pressure, and type of solvent, viscosity oil, residual water saturation and horizontal permeability are addressed in this study. The choice of solvent to be used in the process was the factor that most significantly influenced the process, allowing a greatest recovery factor of oil. The largest cumulative oil recovered was obtained for other parameters of significant influence as the longest distance between wells, increased horizontal permeability and lower injection pressure.