ABSTRACT
Crude oils are often contaminated with water during their recovery. The literature reported on an asphaltenic crude oil, having an API gravity of 41 and a kinematic viscosity of 223 cSt at 608F, containing 7.18 wt% of asphaltenes, 3.1 wt% of wax, and 0.5 wt% of water (Al-Sabagh et al., 2002). The formation of water-in-oil emulsions, their stabilization by solids, rheology, and conductivity was reviewed (Becher, 1987). Different petroleum products are also contaminated with water during their processing, storage, or their use. The early literature reported that fuels can become contaminated with entrained aqueous droplets by the condensation of atmospheric moisture in fuel storage tanks (Hughes, 1969). The literature also reported that, without any agitation, the suspended droplets of water in oil can coalesce. According to Stoke’s equation, for the chosen oil, the density and the viscosity are constant, so the rate of coalescence will depend on the size of the water droplet. For the same viscosity oils, a decrease in oil=water interfacial tension (IFT) will decrease the water droplet size and their rate of coalescence (Hughes, 1969).
