Page 266 - Materials Chemistry, Second Edition

256 G. A. da Silva et al.

in order to produce an inventory minimally representative for cement production
at that period;
• Steel: once again, none of the international steel production LCA databases were
suitable for representing the Brazilian production in 1977, mainly due to the
large use of charcoal. In this context and analogous to the cement case another
independent LCI based again on data from manufacturers, technical reports and
sector analysis from official research agencies was developed;
• Copper: all of its consumption was estimated using international databases,
considering only imports from Chile.

Calculation procedures and data presentation

Once representative LCIs for Itaipu Power Plant were obtained, either a calcula-
tion procedure, or some adjustments were done in order to improve LCI’s clarity.
In an initial analysis, it was noticed that different terminologies were used for
similar burdens. This required nomenclature adequacy, mainly for air emissions
accountability: SO 2 emissions were expressed as SO x ; the same was done with NO
and NO 2 emissions, consolidated as NO x . Solid emissions, independently of the
particles size were consolidated as ‘‘particulate matter’’. Besides, due to the dif-
ferent solid waste flows, all of them were indicated as ‘‘solid waste’’. Energy
resources were expressed as energetic content through the High Heat Value
(HHV). At last, consumption of earth and rock were converted from volumetric to
mass units. Table 3 presents the complete consolidated LCI for Itaipu Power Plant.

Simplified Itaipu Power Plant LCI

Even though a complete LCI was the final objective of the study, an interpretative
analysis of the dataset was conducted. It starts with an evaluation of the most
significant environmental burdens of the LCI. Following the ISO standard (ISO
1998) a cutoff criteria was applied, in order to exclude material and energy con-
sumptions and emissions with cumulative contribution of less than 1.0 %. This
procedure generated a ‘‘Simplified LCI’’. It made possible to conclude that just six
elementary flows—water, rock (basalt), earth, calcite, sand, and iron ore—were, in
fact, significant. Regarding to energy, only four natural resources contributed with
more than 1.0 % of the total: crude oil, coal, hydropower, and natural gas. In terms
of atmospheric emissions CO 2 ,CH 4 , CO, Particulate Matter, SO x and NO x con-
tributed amounted together 99.9 % of the totals for this class. In order to complete
the simplified LCI, ‘‘land use’’ was included, due to the importance of this
parameter to the environmental and social impacts of hydropower. Table 4 pre-
sents the simplified LCI for Itaipu Power Plant, with environmental loads
expressed per functional unit.
This simplified LCI was carried out according to clear and adequate method-
ological procedures and was based on international experiences (OEDC 1992;
ORNL 1994; European Commission 1995; Brännstrom-Norberg et al. 1996;
Swedish Management Council Environmental 1999, 2002a, 2002b; IEA 1998,