Alkali-Surfactant-Polymer (ASP) is one of the most attractive chemical EOR methods. In properly designed ASP formulations, the alkali-surfactant provides ultralow interfacial tension (IFT) between drive aqueous fluid and the displaced oil whereas polymer ensures a good mobility control. Nevertheless, the efficiency of ASP can be much less than expected under various reservoir conditions including low permeability, high temperature, high formation brine salinity, presence of divalent cations (Ca+2, Mg+2) in the formation brine. This is due to polymer degradation or precipitation, low injectivity, scaling in well and surface equipment. This paper reports an experimental study of new a chemical EOR which has the potentially to overcome above drawbacks. The chemical formulation consists of the combination of no-polymeric viscosity enhancement compound and a blend of two surfactants. The performance of this chemical formulation was evaluated by a series of core-flood tests on Bentheimer sandstone cores, under stable gravity conditions, with the aid of X-ray Computed Tomography. A significant reduction of the residual oil saturation was observed by constructing the capillary desaturation curves (CDC) suggesting that proposed formulation is potentially a rather good chemical EOR agent.

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