Functional Principle
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Functional Principle
- When we started the
development of AMESA we selected a modified cooled probe
method acc. EN-1948, which complies more to the US EPA method
23A. In our opinion this method is the most practical method
for long-term sampling of dioxins. The other methods (cooled
probe, filter-cooler) produces condensate which has to be
collected and analysed.
By using the dilution method there exists a higher risk of
dioxin deposits inside the probe, because of the dry process.
Contrary to the cooled probe method by the dilution method
exists no self-cleaning effect due to the condensation of the
flue gas humidity inside the probe.
According US EPA method 23A the collected condensate does not
need to be analysed, because it is well known that the amount
of dioxins in the condensate is negligible. This was
confirmed with AMESA in a lot of measurements in which the
condensate was collected and analysed separately.
The functional principle of the sampling is as follows:
• Extraction of a volume stream constantly and isokinetically
from flue gas
• The dioxins and furans (PCDD/PCDF) are collected in the
adsorption cartridge over a variable period
between 6 hours
and 4 weeks.
• Identification of non-usual operating conditions like e.g.
high O2-value in flue gas, and stop of
measurement if
necessary
• To determine the quantity of the collected dioxins and
furans the cartridge and the SRAM memory card
has to be
analysed by a laboratory which is familiar with the analysis
of PCDD/PCDF-adsorber cartridges
A Cooled (< 70 °C) titanium probe for isokinetic extraction
of a volume stream.
B Measurement stream and condensate are drawn through the
cartridge filled with adsorber resin
(quartz wool as a
prefilter).
C Measurement stream and condensate are drawn through the
measuring gas line to the control cabinet.
D Control cabinet with separation of the condensate by
cooling (< 5 °C) and infinitely variable control of the
isokinetical extraction.
E User-friendly operation of AMESA by menu dialogue in
process controller. Data input for plant specific
parameters
and operation by means of keyboard and LCD-monitor. Analysis
of the emission values by
means of SRAM memory chip and
analysis results.
F Compressed air, power supply and input signal conduits.
G Condensate drain and flue gas recycling
H Signal output (optional)
I Coolant connection (if TFluegas > 70 °C)
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