Effect of non-ionic surfactants on the transport properties of an emulsified heavy oil

• Non-ionic surfactants are used to reduce the viscosity of heavy oils. • Viscosity reduction up to 99% is observed using 1 % W of SAE10 surfactant. • The increment in aggregate size lowers the viscosity and give the Newtonian behavior. • Non-ionic surfactants interact with asphaltenes to decrease interfacial tension. Recent studies in emulsion design are focused on developing systems that reduce the viscosity and interfacial tension of crude oils, to enhance heavy crude oil recovery. In this work, water-heavy crude oil emulsions (W/O) were evaluated at a ratio of 30/70 (w/w %); then, they were modified with three different non-ionic surfactants (viscosity reducers). The W/O/SAE10 emulsion at a 29/70/1 (w/w %) ratio was the most efficient in the heavy crude oil emulsification, improving its flow behavior, since this emulsion exhibits a Newtonian behavior with a viscosity of 150 cP at 35.0 °C. The interfacial tension analysis was carried out at atmospheric conditions. W/O/SAE10 emulsion exhibited interfacial tension values of 9.13 mN m −1 , drop sizes of 150 to 200 nm and unimodal and polydispersed distributions. The addition of a non-ionic surfactant to the W/O emulsions showed a favorable effect on the rheological behavior, stress, droplet size, distribution, and transport properties of the emulsified systems.