Experimental investigation of the effects of various parameters on viscosity reduction of heavy crude by oil–water emulsion

Abstract

The effects of water content, shear rate, temperature, and solid particle concentration on viscosity reduction (VR) caused by forming stable emulsions were investigated using Omani heavy crude oil. The viscosity of the crude oil was initially measured with respect to shear rates at different temperatures from 20 to 70°C. The crude oil exhibited a shear thinning behavior at all the temperatures. The strongest shear thinning was observed at 20°C. A non-ionic water soluble surfactant (Triton X-100) was used to form and stabilize crude oil emulsions. The emulsification process has significantly reduced the crude oil viscosity. The degree of VR was found to increase with an increase in water content and reach its maximum value at 50 % water content. The phase inversion from oil-in-water emulsion to water-inoil emulsion occurred at 30 % water content. The results indicated that the VR was inversely proportional to temperature and concentration of silica nanoparticles. For water-in-oil emulsions, VR increased with shear rate and eventually reached a plateau at a shear rate of around 350 s -1 . This was attributed to the thinning behavior of the continuous phase. The VR of oil-in-water emulsions remained almost constant as the shear rate increased due to the Newtonian behavior of water, the continuous phase.

The effect of fuel injection equipment on the dispersed phase of water-in-diesel emulsions

“…We can then note that the size distribution further reduced inside the common-rail, but then increased again after the injector return. This suggests that the emulsion is affected by the elevated temperatures in the common-rail, most likely due to viscosity and surface tension being inversely proportional to temperature [61] thus producing small droplets [62], but coalescence then occurs between the rail and the injector line as the fuel cools down [63,64]. Finally, the spray sampled after the injector nozzle contained very fine droplets compared to the other samples, and a visibly reduced concentration.…”

New Amphiphilic Macromolecule as Viscosity Reducer with Both Asphaltene Dispersion and Emulsifying Capacity for Offshore Heavy Oil

“…The underlying rationale might be that when the water content is less than 20%, water-in-oil (W/O) emulsion is formed and viscosity increases with water content. As the water content becomes more than 20%, phase inversion occurs, i.e., oil-in-water (O/W) emulsion forms in the system, and the emulsion viscosity starts declining. , Furthermore, it is worth mentioning that due to the high hydrophile–lipophile balance (HLB) of HOA, O/W is formed at a relatively low water content (i.e., 20%).…”

“…As the water content becomes more than 20%, phase inversion occurs, i.e., oil-in-water (O/W) emulsion forms in the system, and the emulsion viscosity starts declining. 56,57 Furthermore, it is worth mentioning that due to the high hydrophile−lipophile balance (HLB) of HOA, O/W is formed at a relatively low water content (i.e., 20%).…”

Effect of NaCl concentration on stability of a polymer–Ag nanocomposite based Pickering emulsion: validation via rheological analysis with varying temperature

“…31,[52][53][54] Factors such as effect of salts, concentration of aqueous phase, and temperature can lead to signicant change in the viscosity of an emulsion. 4,28,35,55 This section presents shear rheological properties of emulsions stabilized by low (15 wt%) and high (25 wt%) compositions of PAHz-Ag NC, and the impact of various ionic strength (1.0-5.0 wt%) on these properties is discussed. Fig.…”