A comparative investigation on viscosity reduction of heavy crude oil using organic solvents

Abstract

The transport of heavy crude oil from the head-well to the refinery plants is an attractive factor as its production is currently increasing around the world. Though the higher viscosity increases trouble in the piping transportation and production from the reservoir, for these reasons, this study focuses on the dilution method to reduce its viscosity using toluene, dimethyl ketone (DMK) and a mixture of (50/50 vol. %) toluene/dimethyl ketone as a dilutes solvents with different weight fraction (0, 5, 10 and 15 wt. %) at 298.15 K. The heavy oil used collected from Amara oil field, south of Iraq. The viscosity was measured by Brookfield viscometer over a range of shear rates (0-42s-1). On another way to understand the effect of temperature, the better result for weight fraction of solvents in viscosity reduction of heavy oil was investigated under different temperatures (298.15, 308.15 and 318.15 K). The obtained results showed dilution of heavy oil samples with toluene, DMK and a mixture of (50/50 vol. %) toluene and DMK is an effective method for reducing the viscosity. Moreover, the temperature has a significant effect on the degree of viscosity reduction in the presence of the diluents. However, the higher DVR was noticed about 87.17 % at 15 wt. % of the mixture (50/50 vol. %) toluene + DMK at 318.15 K and shear rate 42 s-1. Tthe relevant results attribute to an aromatic characteristic of toluene which allows interferes in the asphaltene aggregation.