ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Viscosity reduction of heavy crude oils and synthetic oils with various types of rheological behavior by nano-silica fluids

Hossein Ameri, Meysam Motahari, Komeil Ghahramani, and Jamshid Moghadasi

Department of Petroleum Engineering, Ahwaz Faculty of Petroleum, Petroleum University of Technology (PUT), Ahvaz, Iran

E-mail: hossein.ameri@afp.put.ac.ir

Received: 1 February 2022  Accepted: 12 June 2022

Abstract:

Nanotechnology has significant applications in the petroleum industry, and it is vastly used for various purposes in this industry, such as heavy oil production. This paper investigates the effect of hydrophilic and lipophilic nano-silica particles on the viscosity of two different heavy crude oils (GS and MN) and an asphaltene-synthetic oil. The GS and MN oils indicate pseudoplastic and dilatant rheology behavior, respectively. The viscosity alteration of heavy oils was examined at five various weight fractions of nanofluids containing 1–5%. The nanofluids were procured by dispersing nano-silica particles in multiple base fluids (Ethylene Glycol, Toluene, n-Heptane, and Ethanol) with five concentrations of 0.1–0.5%. To begin with, the findings illustrate that the hydrophilic nano-silica increased the viscosity of both synthetic and crude oils, whereas lipophilic nano-silica demonstrated different influences. The lipophilic nano-silica decreases the viscosity of the synthetic oil with any asphaltenes. Whereas, in heavy crude oils, at the optimum point (0.2% nano-silica concentration and 4% nanofluid weight fraction), the viscosities were reduced by more than 50% and 30% for GS (21.49API) and MN (30.2API), respectively. Also, the lipophilic nano-silica influences the viscosity reduction of heavier hydrocarbons more remarkably than the lighter ones. Furthermore, despite alleviating the viscosity more rigorously than others, Toluene-based nanofluids would be inappropriate to select due to possessing a harmful impact on health. Thus, to reach the highest crude oil viscosity reduction with acceptable safety, this study recommends Ethylene Glycol to be the base fluid for dispersing nano-silica particles within the optimum point.

Keywords: Nano-silica fluids; Heavy crude oil; Synthetic oil; Viscosity reduction

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-022-02331-9

Chemical Papers 76 (10) 6499–6515 (2022)