Portal de Periódicos da CAPES

Gas-Phase Viscosity of Hydrocarbon Mixtures

1964; Society of Petroleum Engineers; Volume: 4; Issue: 03 Linguagem: Inglês

10.2118/872-pa

2469-8490

A. L. LEE, B. E. Eakin,

Thermodynamic properties of mixtures

Abstract Atmospheric pressure viscosity values for light hydrocarbons were calculated by a simple mixing rule based on the Sutherland constants for pure components. This method was further extended so that the atmospheric pressure viscosity of a mixture may be calculated based on the molecular weight information only. Introduction A proven method for estimating the gas-phase viscosity of a mixture is the one by Herning and Zipperer. This mixing rule has the following form: (1) One method for calculating the pure component viscosity mu is the Sutherland equation, which has the following form: (2) The Sutherland constants B and S are determined from experimental data. A set of Sutherland constants for light hydrocarbons based on the data of several investigators is presented in Table 1. APPLICATION The Herning-Zipperer equation and the Sutherland equation were used to obtain an equation for calculating the gas-phase viscosity of light hydrocarbons. This equation has the form, (3) where, (4) and (5) Eq. 3 was used successfully in the study of methane-n-butane mixtures. Further analysis indicated that the Sutherland constants are a function of molecular weight. The gas-phase viscosity may be calculated based on molecular weight information only. The following equation was developed: (6) The atmospheric pressure viscosity of ethane, propane, n-butaneandfourmethane-propanemixtwes calculated on the basis of Eq. 6 are compared with the data of other investigators in Tables 2, 3, 4 and 5, respectively. A plot of atmospheric pressure viscosity vs molecular weight based on Eq. 6 is presented in Fig. 1. SPEJ P. 247ˆ