Use of new generation chemicals and nano materials in heavy-oil recovery: Visual analysis through micro fluidics experiments

Abstract

A series of 2-D etched glass micromodel (sandstone replica with a fracture) experiments were designed to investigate the mechanics of chemical injection with and without pre-solvent injection to recover heavy-oil from heterogeneous porous media. Conventional surfactants (sulfonate series) as well as new generation chemicals (nanofluids, ionic liquids) were tested for this purpose. After testing and screening effective chemicals without pre-solvent injection, the same chemicals were used to retrieve the solvent and recovery additional oil for pre-solvent injected systems. The micromodel was saturated by dyed processed oils and a selected solvent was injected through the fracture. After the solvent was diffused into matrix completely to recover the oil in it, the model was heated mimicking a thermal method to reach the boiling point of the solvent and retrieve it. Following the heating phase, aqueous phase was injected to retrieve the remaining solvent in the liquid or vapor phase. Visual observations on chemical flooding process clarified the complex interactions among different phases considering small-scale heterogeneities. This information can help screen promising chemical and determine the efficiency of chemical injection with and without pre-solvent injection for EOR in heterogeneous sands and carbonates.