Improved equations for the Standing-Katz tables

摘要

Z-factors for natural gas (NG) mixtures come from equations of state,tables or charts and are critical in predicting NG flowrates in pipelines.The first approach requires an accurate formulation for the pure components that constitute the mixture,compositions of at least N-1 components and accurate mixing rules.Even though this approach is the ultimate goal,for simplicity,charts for natural gas z-factors have appeared in the past.Standing and Katz published a chart for the z-fac-tor that is reliable for reservoir gas and gas condensate mixtures.