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TABLE 8.23
Time Average Concentration in On-Site Environmental Media

Compartment Unit Mercury
t
Air mg/m 3 3.13 × 10 –10
Total leaf mg/kg(total) 1.92 × 10 –12
Ground-surface soil mg/kg(total) 2.96 × 10 –9
Root-zone soil mg/kg(total) 2.13 × 10 –9
Vadose-zone soil mg/kg(total) 1.23 × 10 –9
Ground water mg/L(water) 6.99 × 10 –14
Surface water mg/L 2.39 × 10 –12
Sediment mg/kg 2.09 × 10 –9

8.4.5 INTERPRETATION OF THE ENVIRONMENTAL IMPACT ANALYSIS
FOR THE INDUSTRIAL SEPARATION PROCESS
The LCI indicates the relevance of fugitive emissions (VOC) in the case of an
industrial separation process of isopentane from naphtha. The LCIA in relation to
the LCI allows the conclusion that the energy generation sub-process is the most
relevant process of those considered. Therefore, this process is selected for further
analysis if the potential environmental impacts correspond to actual impacts, i.e.,
damages.
The IPA shows that main damages are produced by the particles, NO and the
x
secondary pollutants nitrates and sulfates. This is in line with the results obtained
for the MSWI case study (see Chapter 5). The ERA for mercury points out that
there is a very low risk for human health impacts in the neighborhood due to mercury
exposure based on the fictitious data used for the industrial separation process
-6
example. However, this risk is higher than 10 and therefore not really acceptable
according to guidelines mentioned in Chapter 4. A further reduction of the mercury
emissions in electricity generation process is thus recommended.
Altogether, this comprehensive environmental impact analysis gives a much
more complete picture of the environmental implications of the industrial separation
process than each tool applied independently. Moreover, since the databases are
common and a lot of work is needed for their collection, the subsequent application
of the different analytical tools seems to be a way to get ahead in the future.

8.5 CONCLUSIONS FROM THE APPLICATIONS

Three examples have been presented in this chapter to evaluate the principle appli-
cability of the strategy outlined in Chapter 6 to integrate LCA and ERA where
possible in industrial processes other than the municipal solid waste incineration:

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