Page 18 - Materials Chemistry, Second Edition

2 1 Introduction

Extraction of raw material
including energy carrier

Transport
Production of
intermediate product
Transport
Production of
end product
Transport

Use phase

Transport
End-of-life
(disposal and/or recycling)

Figure 1.1 Simplified life cycle of a tangible product.

of economical and social factors distinguishes LCA from product line analysis
7)
(PLA) (Produktlinienanalyse) and similar methods. This separation was made
to avoid a method overload, being well aware that a decision, for example, in
the development of sustainable products, cannot and must not neglect these
factors. 8)

1.1.2
Life Cycle of a Product

The main idea of a cradle-to-grave analysis, that is, the life cycle of a product,
is illustrated in a simplified manner in Figure 1.1. Usually, the starting point
for building a product tree is the production of the end product and the use
phase. Further diversification of the boxes in Figure 1.1 into singular processes,
the so-called unit processes, as well as the inclusion of transports, diverse energy
supply, co-products, and so on, turn this simplistic scheme, even with simple
products, into very complex ‘product trees’ (diverse raw materials and energy
supply, intermediate products, co-products, ancillary material, waste management
including diverse disposal types and recycling).
Interconnected unit processes (life cycle or product tree) form a product system.
The centre is a product, a process, a service or, in the widest sense, a human

7) Projektgruppe ¨ Okologische Wirtschaft (1987) and O’Brien, Doig and Clift (1996).
8) Kl¨ opffer (2008).