ELTRA CS-2000, Руководство пользователя

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Analysis
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Remark
The marker can be a piece of tape wrapped around the rod. Check the right position of the
marker by pushing another sample up to the level of the marker. The marker is at the correct
position when the sample takes 3 to 5 seconds to ignite after stop pushing. Otherwise repeat
and check again.
Once the marker is at the correct position, all samples of the same kind of material are inserted
into the furnace up to the point shown by the marker on the rod and left there for analysis. This
position corresponds to an area just before the hot zone. The sample then ignites in about 3 to
5 seconds. The signals of the IR-cell go up. They can be observed on the computer screen.
When the signals are moving down and have reached about 25% of their maximum peaks,
push the combustion boat up to the boat stop to reach the middle of the hot zone, to completely
burn any rest of the sample.
NOTICE
It is very important to run the analysis this way!
Never push such kinds of samples immediately into the hot zone.
Some fumes may leave the hot zone without being completely burned. They may contaminate
the gas flow system, including the infrared cell.
Some users push the sample “slowly” into the furnace up to the hot zone. This is wrong. The
sample must stay at the ignition point and after the peak comes down to a low level, then the
boat should be pushed into the hot zone.
5.6.2.3 Ash analysis
•
Adjust the furnace temperature to 1450 °C.
•
Take 200 mg sample weight. The weight can also be much higher, depending on the C
and S concentrations and on the sensitivity of the IR-cells.
•
After starting the analysis, push the sample up to the middle of the hot zone, resp. up to
the boat stop.
Ash content determination:
Close the adjustable flow restrictor (on the resistance furnace front panel, below the flow meter).
Turn it clockwise up to the end. Adjust the furnace temperature between 790 °C and 800 °C.
Take about 1g sample in a quartz boat. Insert the sample into the furnace, just at the beginning
of the hot zone. Leave the sample for one minute. Push the sample into the hot zone and leave
it there for 6-7 minutes.
After combustion, remove the sample. After cooling down, weigh the sample again. This is the
weight of the remaining ash.
The percentage of ash contents is calculated as follows:
100
 
before
after
W
W
C[%]
Where:
–
C: ash contents in the sample;
–
W after: sample weight after combustion;
–
W before: sample weight before combustion;
C and S determination :
For sulfur and carbon analysis, readjust the flow restrictor until the lower flow meter of the
resistance furnace shows 200 l/h. Ensure that the moisture absorber is dry, replace if
necessary, even if the signals of the infrared cells are ignored when determining ash. The gases
passing through the IR-cells have to be dry in any case.