Annual Danish informative inventory report to UNECE. Emission ...

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over several years so there will be an offset in the use and production,
import and export balance over time.
In some industries the solvents are consumed in the process, e.g. in the
graphics and plastic industry, whereas in the production of paints and
lacquers the solvents are still present in the final product. These products
can either be exported or are used domestically. In order not to
double count consumption amounts of NMVOCs it is important to keep
track of total solvent use, solvents not used in products and use of solvent
containing products. Furthermore some chemicals may be represented
as individual chemicals and also in chemical groups, e.g. “oxylene”,
“mixture of xylenes” and “xylene”. Some chemicals are better
inventoried as a group of NMVOCs rather than individual NMVOCs,
due to missing information on use or emission for the individual
NMVOCs. The Danish inventory considers single NMVOCs with a few
exceptions.
Activity data for chemicals are thus primarily calculated from Equation
1 with input from StatBank DK (2008). When StatBank (2008) holds no
information on production, import and export or when more reliable information
is available from industries, scientific reports or expert
judgements the data can be adjusted or even replaced.
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For each chemical the emission is calculated by multiplying the consumption
with the fraction emitted (emission factor), according to:
Emission = consumption * emission factor
The present Danish method uses emission factors that represent specific
industrial activities, such as processing of polystyrene, dry cleaning etc.
or that represent use categories, such as paints and detergents. Some
chemicals have been assigned emission factors according to their water
solubility. Higher hydrophobicity yields higher emission factors, since a
lower amount ends in waste water, e.g. ethanol (hydrophilic) and turpentine
(hydrophobic).
Emission factors are categorised in four groups in ascending order:
• Lowest emission factors in the chemical industry, e.g. lacquer and
paint manufacturing, due to emission reducing abatement techniques
and destruction of solvent containing waste.
• Other industrial processes, e.g. graphic industry, have higher emission
factors.
• Non-industrial use, e.g. auto repair and construction, have even
higher emission factors.
• Diffuse use of solvent containing products, e.g. painting, where practically
all the NMVOC present in the products will be released during
or after use.
For a given chemical the consumed amount can thus be attributed with
two or more emission factors; one emission factor representing the
emissions occurring at a production or processing plant and one emission
factor representing the emissions during use of a solvent contain-