Page 243 - Materials Chemistry, Second Edition

11.5 A composite life cycle sustainability index 241
TABLE 11.8 Other typical indicators for social assessment of the industrial systems (Ren et al., 2016;
Xu et al., 2018b).
Indicator Description
Social It represents the degree of the acceptability of the investigated system, which is characterized as
acceptability an indicator of individual opinions
Social benefit It is a generic indicator that can be defined specifically according to a certain concern with
respect to the investigated system, for instance, the benefit of job creation
Inherent safety It measures the inherent hazard of the investigated system, which could be extended into the life
index cycle perspective
Government It refers to the government support regarding establishing and/or running a certain industrial
support system by setting corresponding policies

From the above-mentioned frameworks and indicators, the evaluation of social concerns
regarding the industrial systems relies heavily on people’s subjective judgements according
to the specific characteristics and necessities of the investigated system, failing to offer a ge-
neric social index that embraces both quantifiable and unquantifiable indicators. Therefore,
more efforts should be put into the development of life cycle-based social indicators for im-
proving the usability of the S-LCA tools.

11.5 A composite life cycle sustainability index

As stated before, dozens of criteria from the environmental, economic, and social dimen-
sions can be selected for assessing the industrial systems, resulting in difficulty aggregating
multiple criteria for representing the overall sustainability. Therefore, this subsection aims at
developing a novel composite life cycle sustainability index that can integrate multiple
criteria from the triple-bottom-line concerns for the prioritization of the industrial systems.
In this subsection, a composite index is proposed, based on the work of Xu et al. (2017,
2018b). Subsequently, a case of the prioritization of five low-carbon ammonia production sys-
tems by using the composite index is studied. Finally, sensitivity analysis is conducted for
demonstrating the feasibility of the composite life cycle sustainability index.

11.5.1 Development of a composite life cycle sustainability index

Because of the absence of general standardized indicators, the overall life cycle sustainabil-
ity of the industrial systems is always hard to measure, especially when dozens of environ-
mental, economic, and social indicators could be selected. Therefore, this subsection focuses
on the development of a composite life cycle sustainability index for the prioritization of in-
dustrial systems.
Since life cycle-based sustainability can be presented by the TBL-based three-dimension
(3D) cube, as shown in Fig. 11.6 (Moradi-Aliabadi and Huang, 2016), the overall sustainability
of an industrial system has recently been depicted by a vector function. In the 3D cube, x, y,
and z, respectively, stand for the environmental, economic, and social pillars, α, β, and γ are