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Product news
Product news
ADIOX
®
ABSORBS DIOXINS
At Måbjergværket in Denmark, wet
The ADIOX
®
technology for dioxin
Adiox scrubbers - in combination with
removal was first introduced on the
two lines of electrostatic precipitators -
market in 2002. It has now been
have acted as the main dioxin filters
installed in 35 waste incineration lines in
since late 2004. According to Götaverken
various countries including Sweden,
Miljö AB, all 11 dioxin measurements
Denmark, Norway, Finland, Germany,
undertaken to date show that the
France and the Netherlands. The
concentrations in the stack are far below
majority of the deliveries have been
the EC waste incineration emission
tower packings made with Adiox
directive limit for dioxins of 0.1 ng
material and installed in wet scrubber
TEQ/m
3
(n, d.g., 11 % O
2
; ‘n, d.g.’
systems, but now dry Adiox absorbers
stands for ‘normal, dry gas’).
are also offered to the market.
A dry pilot absorber, using Adiox
The Adiox development started with
tower packings, was installed at line 1 of
the observation that plastics can absorb
the Renova municipal waste incinerator
large amounts of dioxins from gases
in Göteborg, Sweden in 2004. The pilot
which can later be desorbed. This
absorber extracts approximately
absorption-desorption equilibrium,
3000 m
3
/hour of flue gas (at actual
known as the Memory Effect, can cause
temperature and O
2
content). During
long periods of dioxin desorption from
the first year of operation, the
plastic surfaces. In order to avoid dioxin
inlet concentrations ranged from
release from the material, carbon
0.7 to 2.0 ng I-TEQ/m
3
(n, d.g., 11% O
2
),
particles are dispersed in a polymer such
and the clean gas concentrations from
as polypropylene (PP). The dioxins are
0.002 to 0.02 ng I-TEQ/m
3
(n, d.g., 11%
first absorbed into the PP in this
O
2
). There was no apparent trend of
material. Then they diffuse to the
decreasing removal efficiency with time.
surface of the carbon particles, where
The highest temperature in this test was
they are irreversibly adsorbed. The PP
90°C. Initial tests with high-temperature-
acts as a selective barrier, which protects
resistant Adiox have also been made.
the carbon from other contaminants.
When used as a main dioxin filter, the
The technology has proved to be so
required amount of Adiox material is
successful that it is now recognized not
determined on the basis of the dioxin
only as a means to minimize the
concentration in the raw gas. When used
Memory Effect but also as a competitive
in a dry absorber instead of in a wet
method for dioxin abatement.
scrubber, the removal efficiency per
installed amount is higher, which leads
to smaller equipment sizes. A simple,
cost-effective pollution control system
can be obtained by combining an
electrostatic precipitator, a multi-
functional wet Adiox scrubber and a dry
Adiox absorber.
The system is static, which makes it
robust and reliable. It is effective even
during start-up and upset operating
conditions, indicates Götaverken Miljö
AB. After some years of use, Adiox can
be incinerated, thereby destroying the
dioxins and avoiding harmful substances
being landfilled.
n
More info from
Götaverken Miljö
on
+46 31 501995 or at www.gmab.se
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