A Current Viscosity of Different Egyptian Crude Oils: Measurements and Modeling Over a Certain Range of Temperature and Pressure

Abstract

Viscosity is an important characteristic of crude oil. The viscosity has significant effect for all events in the pipeline transportation of crude oil. The changing in viscosity of crude oil is depending on the temperature, pressure and chemical composition of the crude. In the determination process of crude oil viscosity operations, it is usual to use only temperature dependence of viscosity while the pressure is neglected. Therefore, the essential goal of this study is to obtain a model that can successfully calculate the viscosity in a wide range of temperatures and pressures. Moreover, at this study a mathematical model of changing the current viscosity of Egyptian crude oil with changing of temperature and pressure is determined. Different API gravities of 6 oil samples ranging from 13.4 to 40.4 are tested. The current viscosity measured at the temperature and pressure ranges from 20 to 140°C and from 14.7 to 132.3 psi. These measurements are determined by using the quartz process viscometer apparatus. The comparison between the experimental data and the calculated values is indicated that the proposed model successfully calculate the experimental data with an average absolute percentage relative error of less than 3 and correlation coefficients of 0.991. It is noted that it’s possible to predict a correlation for the dead crude oil viscosity using temperature and pressure change, because the pressure is important for the viscosity and cannot be neglected.