Interfacial Energy During the Emulsification of Water-in-Heavy Crude Oil Emulsions

Abstract

-The aim of this study was to investigate the interfacial energy involved in the production of water-in-oil (W/O) emulsions composed of water and a Brazilian heavy crude oil. For such purpose an experimental set-up was developed to measure the different energy terms involved in the emulsification process. W/O emulsions containing different water volume fractions (0.1, 0.25 and 0.4) were prepared in a batch calorimeter by using a high-shear rotating homogenizer at two distinct rotation speeds (14000 and 22000 rpm). The results showed that the energy dissipated as heat represented around 80% of the energy transferred to the emulsion, while around 20% contributed to the internal energy. Only a very small fraction of the energy (0.02 -0.06%) was stored in the water-oil interface. The results demonstrated that the high energy dissipation contributes to the kinetic stability of the W/O emulsions.

Trending approaches on demulsification of crude oil in the petroleum industry

“…During the formation of emulsion (Fig. 2), the deformation of a droplet is adversarial through the pressure gradient between the internal (concave) and external (convex) components of an interface [30]. The velocity or pressure gradient for the formation of emulsion requires essential furnish through agitation.…”

“…Moreover, there can be an addition of adequate surfactant or surface-active component to the system to minimise the required agitation energy in the production of precise droplet size. The emulsification process is facilitated by the surfactant film formation around the droplets that can achieve a minimised agitation energy using a factor of 10 or more [30].…”

Modelagem Reológica Fracionária Do Comportamento De Fluência De Dois Petróleos Brasileiros E Suas Emulsões a/O.

“…Este depende da composição química e de fases, do grau de dispersão das partículas e das interações intermoleculares. Em particular, reconhece-se que a fração de asfaltenos no petróleo é um dos principais responsáveis pelas altas viscosidades dos óleos pesados [7] e contribuem para a formação e estabilização de emulsões [8]. Além disso, o processo de produção de petróleo é geralmente acompanhado de teores variáveis de água, possibilitando assim a formação de emulsões estáveis ao longo do caminho entre o reservatório e as instalações de superfície.…”

Chemical Demulsification of Model Water-in-Oil Emulsions With Low Water Content by Means of Ionic Liquids

“…Additionally, w/o emulsions usually exhibit viscosities significantly higher than crude oil, thus increasing the pumping costs for the transport of oil in pipelines (Peña et al, 2005). The formation of emulsions is promoted by the mixing in the equipment used in both the stages of petroleum extraction and refining and they are stabilized by the presence of natural surfactants (Karcher et al, 2015). Surface active agents commonly occurring in crude oils, such as asphaltenes, resins, waxes and solid particles, form rigid films at the water-oil interface, which prevent the coalescence of water droplets (de Oliveira et al, 2010;Fortuny et al, 2007;Issaka et al, 2015;Schramm, 1992;Silva et al, 2013;Sjӧblom et al, 2003;Yang et al, 2009).…”