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is associated with a higher global warming potential (GWP) and nutrification poten-
tial (NP) than Scenario 1, i.e., the former operation, because it has a higher CO 2
and NO emission per produced TJ due to additional energy consumption for the
x
advanced gas treatment system. Scenario 2 also has a higher ozone depletion poten-
tial (ODP) and photochemical ozone creation potential (POCP) caused by the higher
contribution of the transport.
Scenario 2 is more favorable than Situation 1 in cases of acidification potential
(AP) and winter smog (SO equivalent) due to the reduction of HCl, SO and dust.
2
2
This scenario is also favorable for heavy metals (Pb equivalent) and carcinogenic
substances (PAH equivalent) because they are removed by the advanced gas treat-
ment system.
The global environmental evaluation according the Eco-Indicator 95 is positive
for the installation of the advanced gas treatment system. The method assigns
especially high weightings to impacts reduced by the advanced gas treatment system
(mainly acidification and heavy metals). Therefore, it can be concluded that the
installation of an advanced gas treatment decreases stack emissions and the related
inventory and impact assessment data, but increases the majority of the other envi-
ronmental loads considered because of higher raw material and energy consumption
per produced TJ as well as more transport activity. Nevertheless, the overall envi-
ronmental efficiency measured according Eco-Indicator 95 clearly improves.
Furthermore, the results obtained with Eco-Indicator 95 methods are comparable
with results obtained from other LCIA methods: MIPS (Schmidt-Bleek, 1994), EPS
(Steen and Ryding, 1992) and the method of the Tellus Institute (1992). Figure 3.12
shows overall results for the difference between Scenario 1 without and Scenario 2
with an advanced gas system.
It can be observed that selected methods corresponding to different weighting
approaches do not deliver results with the same tendency. Two methods show an

80%
60%
40%
20%

0%
Eco-indicator 95 MIPS EPS (1992)* M todo Tellus**
-20%
-40%
-60%
-80%
* Only emissions, values taken from Lindfors et al., 1995
** Without CO 2 , values taken from Lindfors et al., 1995

FIGURE 3.12 Comparison of different single-index LCIA methods.

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