Abstract
From both the theoretical and experimental standpoints, the writer studied the mixing of solvent and oil at the solvent injection into oil reservoirs or its models.
As the results, the following are chiefly indicated by this study:
1. The length and shape of mixing zone are controlled by the following factors, namely, elapsed time, distance, flow velocity, porosity, permeability, pressure gradient, water saturation, diffusion coefficients, viscosity, properties of crude oil and solvent, and temperature etc.
2. The occurrence of mixing zone between solvent and oil will be caused by the action of solvent flooding and/or solvent extraction. The former is piston-like displacement, the latter is dragging-like displacement. The dragging-like displacements would occur, to a great extent, in some cases such as in the low-viscosity solvent into high-viscosity oil.
