Utilization of Water Salinity as a Continuous Miscible Tracer in Waterflooding

Abstract

ABSTRACT An experimental simulation on the miscible displacement in fractured oil reservoir is presented. The theoretical and experimental studies are based on the ideas originally developed by Coats and Smith and recently modified by Perez-Cardenas in connection with miscible and immiscible displacements in heterogenous media which contain a double-porosity system. The proposed model considers that fluid displacement takes place through the fracture system by Convection-Dispersion process, while the matrix blocks exchange matter with the fractures mainly by hydrodynamic dispersion and molecular diffusion. To test the theory and experimental model, several displacements simulations were carried out with real field data. This paper describes application of two-dimensions simulations to miscible displacement during waterflooding operations. The first section describes a method of calculating the behavior of a water salinity tracer by use of an analytical solution for the Dispersion-Convection Equation. The second section of this work extends the analytical results in Berea sand cores. Finally, the last section covers the field simulation, thus the objective is to study the tracer evolution for frontal displacement simulation. Results are presented on calculations of salinity digital images for each evolution step at several pore volume injected and levels of mechanical dispersion-convection.