Page 79 - Materials Chemistry, Second Edition

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3
Life Cycle Inventory Analysis

3.1
Basics

3.1.1
Scientific Principles

1)
The revised ISO standard 14040:2006 defines ‘life cycle inventory LCI’ analy-
sis – as a
phase of life cycle assessment involving the compilation and quantification of
inputs and outputs for a product throughout its entire life cycle.

LCI is a material and an energy analysis based on a simplified (linear) systems
analysis, whereby loops can only be solved approximately by iteration. Calculation
procedures based on matrix inversion can also assess loops. However, calculation
2)
procedures most frequently used so far are based on spread-sheet analysis to be
found in software programmes of the type ‘Microsoft Excel’.
A figurative presentation of the product system is the ‘product tree’ consisting
of process units. The product tree should have been developed, at least roughly,
in the first phase of life cycle assessment (LCA), the ‘Goal and scope Definition’
(Chapter 2), and has now to be refined. Software packages for conducting LCAs
3)
help to elaborate the system flow charts.
LCI in its scientific part – by and large – is based on the following laws of nature:
1. Conservation of mass.
2. Conservation of energy (first principle of thermodynamics)
The following applies for the conversion of thermal energy into other
forms of energy – part of almost all LCAs – as well as to chemical
thermodynamics.

1) ISO (2006a Section 3.3).
2) Heijungs and Suh (2002, 2006).
3) For example, Gabi (PE-International), www.gabi-software.com; SimaPro (Pr´ e Consultants)
www.pre.nl/software.htm; TEAM (Ecobilan), www.ecobalance.com/fr˙team.php; Umberto (ifu),
www.umberto.de. Pionier-Software programs see Vigon (1996), Rice, Clift and Burns (1997) and
Siegenthaler, Linder and Pagliari (1997).

Life Cycle Assessment (LCA): A Guide to Best Practice, First Edition.
Walter Kl¨ opffer and Birgit Grahl.
c 2014 Wiley-VCH Verlag GmbH & Co. KGaA. Published 2014 by Wiley-VCH Verlag GmbH & Co. KGaA.