Galvanic Applied Sciences AccuChrome MA2963, Operation Manual

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Revision 4 121 12/15/2018
Response Factor: The correction factor used to convert peak area into
concentration.
Retention Time: The time that elapses between the start of an analysis and the
maximum height of a peak. Peak retention time is used to
identify individual components in an analysis.
Saturated BTU: The heating value of a standard cubic foot of gas saturated
with water vapour.
Specific Gravity: The ratio of the density of a substance to the density of air at
the same temperature.
Standard Cubic Foot: The quantity or volume of gas occupying a cubic foot of space
at 60
°
F and 14.696 PSIA.
Wobbe Index: The Wobbe Index is defined as the Gross Heating Value
divided by the square root of the Specific Gravity of the gas.
It is an indicator of the interchangeability between different
natural gas compositions.
13.2 Calibration Formulas and Analyzer Calculations
A factory calibration is used to establish the response factors for each component and to
determine the retention time for each compound. The results of this calibration are available
in the Configuration Report. Since the thermal conductivity of the various components is
different, a calibration gas containing all of the components expected in the sample is
required.
Formulas for calculating the response factor, as well as other parameters measured by the
ACCUCHROME, are as follows:
Response Factor
In calibration mode, the analyzer will measure the peak height (area) of several separations
of a calibration standard. An average response factor will be calculated as shown in Section
13.1.
The
Response Factor
is used to calculate the concentration of the components in a run using
equation 13-1.
Concn = RFn × Arean
13-1
Where: Conc
n
= concentration of components n
RF
n
= response factor of components n
Area
n
= area of peak produced by components n