Temperature Dependences of the Rheological Properties of “Viscous Paraffin Oil–Aqueous Phase–Surfactant” Systems

Abstract

By means of vibrational and rotational viscometry, the possibility has been explored to control the rheological properties of heterogeneous systems “viscous paraffin oil–aqueous phase–surfactant” using compositions based on surfactants and alkaline buffer solutions capable of preserving for a long time in a reservoir a set of colloidal-chemical properties optimal for oil displacement. The depressant ability of nonionic surfactants—oxyethylated alkylphenols with various degrees of oxyethylation from 12 to 90 oxyethyl groups in a molecule—with respect to paraffin waxes has been studied, which makes it possible to increase the mobility and lower the pour point of crude oil. The pour-point depressant ability of nonionic and anionic surfactant formulations that are compatible with mineralized reservoir water of oil fields and stable over a wide range of reservoir temperatures has also been studied.