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6 Environmental Damage

Estimations for Industrial

Process Chains*

6.1 INTRODUCTION TO AN INTEGRATED APPROACH
Looking at the picture of life-cycle and risk assessment methods that has been
presented, it seems necessary to come to a spatial differentiation of life-cycles in
order to facilitate a more integrated way of calculating environmental damage esti-
mations in a chain perspective. In this way the poor accordance between impact
potentials and actual impacts can be overcome in life-cycle impact assessment
(LCIA) and the results can become more consistent with the risk assessment
approach. Thus, another approach is needed that differentiates life-cycles according
to the number of processes considered. This means using different levels of sophis-
tication for different applications that are defined by their chain length.
It seems to be unfeasible to estimate environmental damages for each process
of a full life-cycle assessment (LCA), i.e., of a complex product system with a huge
number of industrial processes (e.g., computers), because all the local or regional
information is not accessible and each process is contributing only marginally to
the total environmental impact. Such a life-cycle is illustrated in Figure 6.1.
However, if the LCA methodology is applied to industrial process chains, i.e.,
chains with a small number of industrial processes (e.g., <100 processes) — waste
treatment process chains, for example — the localization of the processes is often
known. Moreover, in general only a small number of processes is responsible for
the main part of the environmental impact, as can be seen in the example of Figure
6.2. Therefore, for such applications of LCA the main individual processes can be
assessed in their corresponding surroundings.
This differentiation of the life-cycle type according to chain length is crucial for
estimating environmental damages in the most accurate way possible. This work
will focus on the methodology development for damage estimations in industrial
process chains, defined here as life-cycles with a relatively small number of processes
involved, in contrast to product systems, i.e., process chains with a high number of
different sites to consider. This chapter presents a comprehensive methodology for
such life-cycle types. It is evident in these cases that different levels of detail in the
impact assessment can be used.

* Extracts of this chapter referring to the mathematical foundation and the Case Study are reprinted from
J. Hazardous Mater., 77, Sonnemann, G.W. et al., pp. 91–106. ©2000 with permission from Elsevier.

© 2004 CRC Press LLC