Correlations for Hydrocarbon-Gas Viscosity and Gas Density—Validation and Correlation of Behavior Using a Large-Scale Database

Abstract

Summary The focus of this work is on the behavior of hydrocarbon-gas viscosity and gas density. The viscosity of hydrocarbon gases is a function of pressure, temperature, density, and molecular weight, while the gas density is a function of pressure, temperature, and molecular weight. This work presents new approaches for the prediction of gas viscosity and gas density for hydrocarbon gases over practical ranges of pressure, temperature, and composition. These correlations can be used for any hydrocarbon-gas production or transportation operations. In this work, we created a large database of measured gas viscosity and gas density. This database was used to evaluate existing models for gas viscosity and gas density. We also provide new models for gas density and gas viscosity, as well as optimization of existing models, using our new database. The objectives of this research are as follows: To create a large-scale database of measured gas-viscosity and gas-density data. This database will contain all the information necessary to establish the applicability of various models for gas density and gas viscosity over a wide range of pressures and temperatures. To evaluate a number of existing models for gas viscosity and gas density. To develop new models for gas viscosity and gas density using our research database; these models are proposed and validated. For this study, we created a large database from existing sources available in the literature. The properties in our database include composition, viscosity, density, temperature, pressure, pseudoreduced properties, and the gas compressibility factor. We use this database to evaluate the applicability of existing models used to determine hydrocarbon-gas viscosity and hydrocarbon-gas density (or, more specifically, the gas z-factor). Finally, we developed new models and calculation approaches to estimate the hydrocarbon-gas viscosity, and we also provide an optimization of the existing equations of state (EOS) typically used for for the calculation of the gas z-factor.