Use of a Novel Surfactant To Prepare Oil-in-Water Emulsion of an Indian Heavy Crude Oil for Pipeline Transportation

Abstract

This article thoroughly evaluates the performance of a synthesized surfactant as an emulsifier for the preparation of an Indian heavy crude oil-in-water (o/w) emulsion to enhance its ability to flow through offshore pipelines. The physicochemical characteristics, wax content, wax appearance temperature, FT-IR spectrum, and high-temperature gas chromatogram of the heavy crude oil were analyzed first. High-frequency (26 kHz) ultrasonic waves were utilized to disperse heavy crude oil in water. Further evaluation included studies of the pour point, rheology, stability, droplet size distribution, and zeta potential of the prepared emulsions. The pour point and viscosity of the crude oil decreased drastically after preparation of the emulsion with water. Most of the prepared emulsions had a pour point of less than 3 °C. In order to minimize the amount of surfactant required, the effects of aqueous-phase salinity and pH on the emulsion properties were also studied. Although an increase in water salinity showed no significant positive effect on emulsion properties, an increase in water pH helped in achieving better flow ability as well as stability of the emulsions. These results suggest that a synthesized surfactant may be used to prepare stable o/w emulsions and transport them through offshore pipelines efficiently.

Viscosity Reduction of Indian Heavy Crude Oil by Emulsification to O/W Emulsion Using Polysorbate‐81

“…Thus, reduction in droplet size results in more stable as well as a viscous emulsion, due to increased number of droplets, large interfacial area, and hence increased particle to particle interactions. Similar results have been observed by various researchers (Abdurahman et al, 2012; Ahmed et al, 1999; Ashrafizadeh and Kamran, 2010; Kumar and Mahto, 2017). From Fig.…”

“…Further, the presence of polyaromatic structure is also observed with weak bending vibrations at 746.04, 813.75, and 869.49 cm −1 . The presence of such aromatic and polyaromatic structures in HCO represents the presence of asphaltenes and resins in HCO (Kumar et al, 2018; Kumar and Mahto, 2017). Weak peaks at 722.16 and 587.97 cm −1 represent rocking vibrations of carbon chain having six or more carbon atoms/more than four methyl groups in HCO.…”

“…The authors in Kumar et al, 2015 and Gudala et al, 2017 have proved that small amount of a naturally extracted surfactant Mahua can effectively reduce heavy crude oil viscosity. Various researchers achieved viscosity reduction from 88.23% to 99.9% using nonionic surfactants for various HCO of API gravity ranging from 12.3 to 19.5 (Al‐Hashmi et al, 2017; Ferreira et al, 2007; Kumar and Mahto, 2017; Kundu and Mishra, 2013; Maran et al, 2013).…”

“…Kumar and Mahto (2017) observed a slight reduction in the emulsion viscosity and significantly enhanced stability by increasing the pH of water from 7 to 11. Abdurahman et al, 2012 showed that on increasing pH from 2 to 10 emulsion stability decreased but the increasing pH from 10 to 11 resulted in increased stability.…”

Characteristics and pH-Responsiveness of SDBS–Stabilized Crude Oil/Water Nanoemulsions

“…Nanoemulsions have the potential to reduce IFT and, accordingly, the capillary pressure of the reservoir [ 1 ], improve rock wettability [ 1 ], ease the fracturing fluid flow-back [ 21 ], eliminate phase trapping [ 21 , 22 ], and increase the regained gas permeability [ 1 , 21 ]. Accordingly, some researchers have recently demonstrated the applicability of nanoemulsions in enhanced oil recovery (EOR) [ 23 , 24 , 25 ], production enhancement (e.g., well stimulation and remediation, well-bore cleaning, and formation fracturing) [ 26 , 27 , 28 ], and pumping of extra heavy crude oil [ 29 ]. For instance, it has been reported that nanoemulsions can (i) minimize/control water-cut [ 28 ], (ii) create new channels for gas flow (i.e., increase gas permeability) [ 28 ], (iii) increase proppant permeability and, accordingly, lower the initial cleanup pressure [ 30 ], (iv) reduce fingering [ 31 ], (v) enhance the flow-back rates of fracturing fluids [ 31 ], (vi) reduce/eliminate water blocking problems [ 27 ], and (vii) minimize surfactant adsorption to the reservoir rocks [ 1 ], among other beneficial effects.…”