ELTRA CS-580A, Руководство по эксплуатации

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Function description
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5 Function description
5.1 Measuring principle
The measuring method is based on the principle of sample combustion and the
analysis of the combustion gases, using infrared absorption.
A wide variety of sample materials in various forms is possible, like powders,
grains, chips, solid pieces and also some materials in liquid form. Typical materials
are coal, ashes, steel, cement, soil samples, rubber, oil etc.
During combustion, the sulphur and carbon components present in the sample are
oxidized to form SO
2
and CO
2
. Typical combustion temperature is 1350°C.
Combustion is obtained by supplying oxygen which at the same time acts as
carrier gas. An electronic flow controller keeps the flow quantity at a constant level
of 180 l/h.
Dust traps and a moisture absorber ensure that a dry, dust free gas mixture is
supplied to the infrared cells.
The output signals of the infrared cells are selective and correspond to the SO
2
and
CO
2
concentrations in the gas mixture. They are electronically linearized,
integrated, divided by the sample weight and displayed as % S and % C values.
Since the sample weight is taken into account, the results don’t depend on the
sample weight. For this purpose, the sample is weighed before analysis and its
weight is transferred to the PC. If necessary, blank values can also be entered; the
PC takes them into account when calculating results.
The graphical representation of the detectors’ signals (peaks) is shown on the PC’s
screen during and after analysis. At the end of analysis the results are displayed as
well. All analyses data for every finished analysis are saved in the PC and remain
available for review, results recalculation, calibration, etc. and they can be printed
out on a printer or exported to another software, if necessary.