Page 102 - Materials Chemistry, Second Edition

98 5. Development and applicability of life cycle impact assessment methodologies

Zamagni et al. (2013) thought that, compared to E-LCA, S-LCA faces two difficulties, in data
and indicators, respectively. Furthermore, the technical framework of LCSA still needs to be
further understood and applied in three respects: environment, economy, and society.

5.2 The environmental assessment—LCA

The LCA is an analysis tool used to compute and evaluate the environmental impact and
resource utilization of a product, a process, or an activity in the whole life cycle, including raw
material mining, raw material transportation, products production, products transportation,
products use, products maintenance, recycling, and final treatment (Rebitzer et al., 2004;
Granovskii et al., 2006; de Haes et al., 1999, 2002). The research of an LCA focuses on the whole
life cycle of a product and other objects to evaluate the environment and resource aspects, so
its level is expressed from cradle to grave (Cabeza et al., 2014; Rafaschieri et al., 1999; Margaret
et al., 1996; Pehnt, 2006).

5.2.1 Technical framework

5.2.1.1 Goal and scope definition
This phase is the first step, and is perhaps the most significant link of an LCA. In this phase,
the expected product of the study, system boundaries, functional unit (FU), and assumptions
are defined (Yue et al., 2013; Guin ee, 2002). The system boundary is often expressed by the
system balance diagram, and also contains processes supporting the life cycle of the product,
process, or activity. The functional unit (FU) standardizes the inventory data and its defini-
tion depends on the affect type of environment and study itself. The FU is the basis of most
products during the study. LCA is a continuous adjustment process. The breadth and depth
of investigation depends on its target. The range of study also depends on the object of study
and the potential application fields of study result (Curran, 1996). With the increasing number
of information, the understanding of the system might be changed. The original target and the
range of the research should also be adjusted.
5.2.1.2 Inventory analysis
In this phase, the data of resource, energy consumption, and contaminant discharged into
the environment, in each stage of an LCA, have been collected and processed. Therefore, this
phase takes the most time of the whole LCA, when data collection may be more time consum-
ing (Hendrickson et al., 2010; Crawford, 2008). The time spent in this section depends on the
quality of the data collected. If a good database is available, as well as customers and suppliers
willing to offer help, the task of inventory analysis should be easier.
The inventory of an LCA is a summary of all inputs and outputs related to the system,
based on the functional input and output data sheets. It is also the basis of the third phase
impact assessment (ISO, 2006b). The correctness of the results depends directly on the quality
of the inventory. The work of inventory analysis is an iterative process, throughout each stage
of an LCA. With the process of collecting and disposal of data, the understanding of the
research system could be deepened continuously. New demands on collection scope and