Liquid Solvent Addition to Steam for Enhancing Recovery of Heavy Oil With Cyclic Steam Stimulation

Interest in exploration of high-viscosity and extra-viscous oil grows every year, but the low mobility of oil significantly complicates of extraction process. To increase the mobility of oil, methods based on injection of steam into formation have been widely used. Thermal impact is particularly costly and not always cost-effective, especially for deep fields. A significant part of energy is spent on warming up non-target intervals and downhole equipment, as a result of which it is not possible to achieve the required values for reducing of oil viscosity. Also, thermal methods find limitations when there is a gas cap in the reservoir, underlying aquifers, with a low porosity and thermal conductivity of rocks ( Knorr, K. 2014 ).

The method of solvent dosing into steam can significantly reduce energy consumption in the production of steam. The main factor of the project’s success is choice type and concentration of solvent, depending on properties of steam and oil.

The purpose of this work is solvents selection study as additives to cyclic steam stimulations for oil deposits in the Volga-Ural region.