Propriedades de emulsões óleo em água formuladas com emulsificantes reconfiguráveis através de alterações no PH

Abstract

Oil-in-water emulsions (o/w) are being used to minimize adversities encountered through flow and pumping of unconventional oil (extra heavy and viscous). Problems are imputed to the high viscosity hindering and/or blocking the pump potential of this type of oil. O/w emulsions are a system, in which the oil is dispersed, as small droplets, in the aqueous phase, which contain the emulsifying agent. Hence, it is possible to transport and pump the oil without direct contact with the pipeline wall, reducing the problems due to the high viscosity of the oil and improving the efficiency in the recovery and production of unconventional oil for the petroleum industry. For the present work, an experimental evaluation was carried out to analyzed properties of emulsions formulated with reconfigurable emulsifiers by changes in the pH. A blend of ethoxylated amines was used as emulsifying agent for oil-in-water emulsions with oil content up to 70% volumetric. Effects of pH and salinity of the aqueous phase on emulsions properties were evaluated, as following: droplets diameter, stability, apparent viscosity and zeta potential. The analyzed parameters were strongly influenced by the pH of the aqueous phase, enabling to manage emulsions properties. Average diameter was under 20 micrometers, resulting in stable emulsions (quantity of aqueous phase separated under 12% volumetric). Emulsions presented negatively charged particles in a wide pH range. The emulsification process produced emulsions with viscosity possible to pump the oil in commercial pipelines (viscosity inferior than 400 mPa.s), being a technical feasible option. Variation of emulsion properties, with the characteristics of the emulsifying agent used, permits the adequacy of these properties as required by the process.