Measuring Method And Measuring Point; Description Of The Measuring Method - Honeywell enCore Series Manual

4 Measuring method and measuring point

In the analysis mode, the gases are measured in a continuous flow every second
and the calculations of the gas composition are updated. The measured values can
be displayed on site and forwarded to a control room, for example.
The application is described and explained in detail in the sections
7 GasLab Q2 operation panel and operation
➪
8 Configuration and analysis software enSuite
➪

4.1 Description of the measuring method

The used correlative measuring principle is based on the determination of infrared
absorption and the thermal conductivity of the gas being analyzed. Instead of the
gas values such as superior calorific value, density at base conditions and CO
tent, the measuring method uses values which are physically related to the target
values and are easier to measure. GasLab Q2 therefore analyzes the following gas
properties:
Infrared (IR) absorption of the CH gas
l
Infrared (IR) absorption of the CO
l
Thermal conductivity of the full gas mixture
l
Pressure and gas temperature
l
All the partial measurements are subjected to a correlative evaluation process
which is based on the physical background, the typical composition of natural gas.
The nitrogen, as well as the superior calorific value, density at base conditions and
CO content can be calculated using an appropriate equation system.
2
The Wobbe index can be calculated using the superior calorific value and density at
base conditions. These values are enough to determine the other properties of the
natural gas. This means that all the main gas components can be identified directly
or indirectly and are available for further processing. The figure shows a schematic
overview of the measuring principle (without pressure and temperature).
GasLab Q2
gas
2
Fig. 4-1: Measuring method
User Manual (N )
(p. 104) and
(p. 171)
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