Set for sampling
fumes to determine contents of heavy
metals and dioxins
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Product
destination
The set of
units offered is destined for isokinetic sampling
of dust and gas in order to determine contents of
polychlorinated dibenzodioxins/dibenzofurans (PCDDs/PCDFs)
and heavy metals such as: mercury, arsenic,
thallium and cadmium - in gases emitted from
stationary sources of emission.
Sampling
procedure, design and principle of operation for
units in the set
The sampling
procedure is consistent with requirements of the
European Standard, EN 1948-1:19961 having status
of the Polish Standard (PrPN-EN 1948-12 being
developed).
The gas/fumes
being tested are taken isokinetically in the
emission duct. PCDDs/PCDFs and heavy metals, both
adsorbed on solid particles and the ones
appearing in gas phase, are collected in the
sampling set. The first method out of the three
mentioned in the standard (EN-1948) is used as
the way of taking the sample i.e. filtration and
condensation method.
The set contains
the following elements :
- aspiration
speed probe
- dust filter
- condensation
& filtration module
- dust meter
- suck-in unit
Sampling
route in the aspiration speed probe (Information
sheet: "Aspiration speed
probe SP-sst, SP-sstg, SP-sstgr type "), including an aspiration
end, is made of titanium. Optionally, the probe
can be made in a heated variant with temperature
adjustment up to 200 °C.
After the
probe, in further part of the aspiration route,
there is a heated filter (105 ÷ 115 °C)
catching solid particles (Information sheet: "Heated
dust separator FS-100g"). In addition, filter
heating can be adjusted electronically up to 200 °C
(Information sheet: "Temperature
regulator RT-200"). This filter, in elements
exposed to the sampled agent, is made of PTFE.
The filter,
through titanium tubes, is connected with the
condensation & aspiration module (Information
sheet: "Condensation and
filtration module for gas sampling for
determination of heavy metal and dioxin contents"). The module includes a
water cooler, condensation container and a flow
container filled with an appropriate sorbent e.g.
XAD type or polyurethane foam insert. Standard
substances PCDD/F identified with carbon isotope 13C
are added to sorbents before sampling - according
to EN-1948 standard - in order to determine
degree of recovery in the sampling process and to
prepare samples for analyses.
After the
module, there is a unit for measuring physical
and chemical parameters of the main stream (in
the duct being tested) and parameters of partial
stream (in the sampling route), and the suck-in
unit with negative pressure control. In the
presented set this job is carried out by a
gravimetric dust meter control unit, EMIOTESTR
series (Information sheet: "Gravimetric
dust meter EMIOTESTR
2598"). Source of forced flow is the suck-in
unit, AZ-15 (Information sheet: "Suck-in
unit AZ-15").
Fumes
samples are sucked in by the measuring probe on
the outlet of which there is an aspiration end
with inlet diameter appropriate to the gas/fumes
flow rate in the duct being tested. Intensity of
fumes flow stream is adjusted automatically by
EMIOTESTR 2598 control unit,
maintaining the criteria of isokinetic aspiration.
Memory of
EMIOTESTR dust meter control unit
registers periodically such parameters of the
main and partial stream as: temperature, absolute
pressure, percentage of vapours and volume stream.
After completion of the measurement it is
possible to send data from EMIOTESTR
dust meter control unit to the computer or to
print reports from the measurement process as
well as final results indicating intensity and
stream of the dust mass.
Results of
heavy metals and dioxins determination are
received in the analytical laboratory after
completion of relevant chemical analyses using
atomic spectroscopy techniques (metals) and mass
spectrometry (dioxins).
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