ELTRA CS-2000, Руководство пользователя

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Function description
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7 Function description
7.1 System overview
The CS-2000 automatic analyzer incorporates the latest in combustion technology. It is
designed for the rapid simultaneous determination of carbon and sulfur in steel, cast iron,
copper, alloys, ores, cement, ceramics, carbides, minerals, coal, coke, oil, ashes, catalysts,
lime, gypsum, soils, rubber, leaves, soot, tobacco, waste, sand, glass and other solid and fluid
materials. The CS-2000 can be supplied with up to three independent Infrared cells, giving the
following options:
1.
Two IR-cells for carbon and one for sulfur.
2. Two IR-cells for sulfur and one for carbon.
These configurations offer optimum precision for the analysis of high and low levels of the
chosen element. The change over from the low to the high range is done automatically during
the analysis and doesn’t require any pre-setting by the operator.
7.2 Measuring principle
The measuring procedure is based on sample combustion and measurement of the combustion
gases by means of infrared absorption.
A wide variety of sample materials in various forms is possible; powder, chips, grains, solid
pieces and also some materials in liquid form. Typical materials are coal, ashes, steel, cement,
soil samples, rubber etc.
During combustion, the sulphur and carbon components present in the sample are oxidised
forming SO2 and CO2. The usual combustion temperature is 1350°C in the resistance furnace.
The sample temperature in the induction furnace depends on the kind of sample and
accelerators as well as on their quantity. Usual temperatures are between 1800°C and 2000 °C.
Combustion is obtained by supplying oxygen, which at the same time acts as carrier gas. An
electronic flow regulator keeps the flow quantity at a constant level of 180 l/h (unless the
analyser is a special model).
Dust traps and a moisture absorber ensure that a dry, dust free gas mixture is supplied to the
infrared cells.
The signals emitted from the infrared cells are selective and correspond to the SO2 and CO2
concentrations in the gas mixture. They are electronically linearized and integrated, divided by
the sample weight and digitally displayed as % S and % C.
Since the sample weight is taken into account, the results do not depend on the sample weight.
For this purpose, the sample is weight is taken before being analysed and entered into the PC.
If necessary, blank values can also be entered; the software takes them into account when
determining results.
The analyser is PC controlled, using the software “UNI”. For information about software, please
refer to the Help-function of the software.
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 analysis
data for every finished analysis are saved in the PC and remain available for review, results
recalculation, calibration, etc. and can be printed on a printer or exported to another software, if
necessary.