Process Displays
AGA8DL & AGA8GS
Revision 9
900 Control Station User Guide
91
May 2014
AGA8DL & AGA8GS
The Detail method (AGA8DL) uses the gas analysis of up to 21 components. From the gas analysis, the
super-compressibility factor, gas density at flowing and standard conditions, and gas relative density at
standard conditions are calculated for input into the AGA calculation for the meter type chosen. Used when
accurate gas analysis is available either via an on-line gas analyzer or from laboratory measurements. The
Detail method can handle up to 21 gas components typically found in natural gas. If this information is
available, the Detail method is preferable, as accurate results are obtainable over a wider range of
conditions than the Gross method.
The Gross method (AGA8GS) is used to approximate natural gas by treating it as a mixture of three
components, equivalent hydrocarbon component, Nitrogen and Carbon Dioxide. It is typically used for dry,
sweet (no H
2
S) natural gas. There are two methods used: Gross Method 1 calculates the super-
compressibility and gas density from knowledge of the relative density, heating value and carbon dioxide,
hydrogen and carbon monoxide components. Gross Method 2 calculates the super-compressibility and gas
density from knowledge of the relative density, Nitrogen, carbon dioxide, hydrogen and carbon monoxide
components.