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| Titel |
Characterization of Aerosol Particles around an Open Pit Coal Mine in Germany |
| VerfasserIn |
Doerthe Mueller-Ebert, Martin Ebert, Stephan Weinbruch |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250038977
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| Zusammenfassung |
| PM10 around open pit coal mines in Germany frequently exceeds the 24 hours limit value of
50 μg/m3. To comply with current EU regulations appropriate mitigation strategies have to be
developed. For this goal accurate source apportionment is an indispensable prerequisite. In
this study characterization of the dust immission was performed by electronmicroscopic
individual particle analysis.
Particles were collected close to the open pit mine from January 2007 until February 2008
with a two stage cascade impactor (aerodynamic particle diameter: 0.4 – 1 μm and 1 – 10
μm). The size, shape, and chemical composition of more than 30,000 particles were
determined by automated scanning electron microscopy (SEM) and energy-dispersive X-ray
microanalysis (EDX).
The most abundant particle groups encountered are secondary aerosol particles, soot,
silicates, silicate/coal mixtures, coal, sulfates, carbonates, Fe-rich particles and (aged) sea
salt.
The relative abundance of the different particle groups is highly variable as function of the
specific meteorological conditions. It can be distinguished between at least three
different scenarios, which were found to cause exceeding of the daily PM10 limit
value.
a) high concentrations of silicates and silicate/coal mixtures which can be assigned to
mining activities,
b) high concentrations of secondary aerosol particles and soot (urban background),
occurring during inversion periods with stagnant air masses, and
c) high concentrations of (aged) sea salt indicating direct transport of air masses from the
North Sea.
PM2.5 and PM1 are always dominated by urban background aerosol (secondary aerosol
particles and soot). Following these results, significant reduction potentials for
PM10 only exist for the contribution of the open pit mine (silicates, silicate/coal
mixed particles) and for urban background aerosols (secondary aerosol particles and
soot).
As the contribution of the open pit mine is mainly apparent in the PM10-2.5 fraction, but
adverse health effects are more likely associated to the PM1 fraction (respectively particle
number concentrations or surface area) a possible conflict of goals in the reduction strategies
may arise depending if the focus is set at permissible value of PM10 or the relevance for
adverse health effects. |
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