A series of laboratory experiments was conducted in which oil was displaced from a porous medium by a solvent slug driven by a porous medium by a solvent slug driven by a miscible fluid.
Two dimensional displacements experiments were carried out on a consolidated porous media representing one fourth of five spot. All fluids were miscible together. Among the variables investigated were slug size, viscosity ratio and sweep efficiency.
Such research with simple fluids was undertaken to provide basic information both for the laboratory study of more complex fluids in the same porous media and for the development of a numerical model capable to predict performance of miscible slug injection.
As the amount of oil to be recovered is determined by the fraction of reservoir contacted by the flood the main purpose of all secondary recovery processes now under investigation is to improve the sweep efficiency of the injected fluid.
Sweep efficiency is largely determined by the fluid mobilities so the study of this last parameter is a step towards a better recovery. parameter is a step towards a better recovery. Several processes tend to improve mobility ratio between oil in place and driving fluid, they can act: on injected fluid viscosity,-on in place fluid viscosity, or: on permeability to injected fluid. In order to have a good displacement efficiency and a good sweep efficiency, all the different secondary processes use slug injection.
For miscible processes, a slug will be injected to reduce oil viscosity and mobility ratio between oil and driving fluid will be reduced.
Others recovery processes use non newtonian fluid injection, a slug of polymer solution or of foam will decrease the permeability of the reservoir to a displacing fluid and improve mobility ratio.
In order to investigate the simple physical phenomena related to flow of fluids with very phenomena related to flow of fluids with very different mobilities ratios, we conducted a laboratory research in a two dimensional porous media.
We studied the injection of slugs using simple miscible fluids.
