A Correlation for the Viscosity of Light Normal Paraffin Hydrocarbon Systems

Abstract

This paper was prepared for the 41st Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to held in Dallas, Tex., Oct. 2–5, 1966. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines. Abstract A graphical correlation of the viscosity data for normal paraffin hydrocarbons and their mixtures based on a pseudo-molecular weight is presented. The correlation reproduces experimental viscosity data for pure component, binary, and multi-component normal paraffin hydrocarbon systems with a standard deviation of +-5 per cent. The formula used to calculate the pseudo-molecular weight is presented together with a graphical representation of the correlation and tables of the smoothed values given by it. Introduction The existing data on the viscosity of hydrocarbon mixtures at high pressures are scarce and there exists a need for methods to enable estimation of the viscosity of these mixtures under the conditions of their production and processing. This paper presents a g graphical correlation for the viscosity of single and multi-component hydrocarbon systems. Special attention has been paid to that range of molecular weight in which the naturally occurring multi-component systems fall. The correlation represents a simple method of predicting the viscosity from a knowledge of the temperature, pressure and composition of the hydrocarbon system involved. Background The viscosity of hydrocarbons at pressure near atmospheric has been extensively studied over a wide range of temperatures. Less work has been devoted to the study of the pressure effect on viscosity, particularly because of the experimental difficulties involved. The scarcity of the available data and the infinite number of possible mixtures, either naturally occurring or man-made, have prompted several authors to investigate the use of theoretically or empirically derived correlations to generalize the existing data. The basis for these efforts have been either the assumption of simple molecular models, or selective use of the available data on a limited number of systems. The kinetic theory approach advanced by Enskog has been the most widely used theoretical basis for correlations. Discussions on the subject, together with proposed equations following this approach have been given by Colburn, Drew, and Worthington, Lype, Gardner, and Woolley, Scott and Brickwedde.