LCA Food 2012 in Saint Malo, France! - Manifestations et colloques ...

PARALLEL SESSION 3B: PACKAGING 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
The emissions stemming from truck transportation due to the burning mainly of diesel fuel have been considered
for the transport of all the main inputs for the manufacturing of packaging materials, from their extraction,
manufacturing of intermediary products up to the obtainment of the final packaging material.
The data relative to the production of LPB were provided by Klabin, the main supplier of the paperboard
used to manufacture the TBA packages. The material is produced from pinus and eucalypyus fibres through
the kraft process at the Telêmaco Borba plant in the South of the country and its inventory collected for 2008
was employed in this study (Mourad et. al, 2012).
The data concerning the production of ethylene (catalytic cracking of naphtha) from crude oil refining were
estimated based on public Brazilian sector data and the study published by Bousted (1992). The manufacturing
of low density polyethylene (polymerisation) from ethylene was quantified from the data obtained from
the two resin suppliers of Tetra Pak and weighted by the rate of supply in 2003.
The data concerning the manufacturing of aluminum foil refer to data collected between 1998 and 2000 and
were provided by all three Brazilian manufacturers of this metal. These data are relative to average aluminium
foil life cycle inventory information surveyed by the Project “Life Cycle Assessment of Aluminium
Products” (Gatti et al., 2000). The energy required for the production of aluminium is almost entirely produced
by hydroelectric plants owned by the aluminium manufacturers.
2.2 Aseptic laminating, filling stages and final disposal
The manufacture of the multilayer laminated plastic and aluminium coated paperboard consists of the printing
of the paperboard, followed by its laminating with aluminium foil with extrusion of low density polyethylene
(LDPE) and the application of internal LDPE layers, also by extrusion. The transportation steps considered
for the manufacturing of the paperboard take into account the distance between the production sites
of raw material suppliers (paperboard, polyethylene, aluminium and ink) and the Tetra Pak manufacturing
plant located in the town of Monte Mor, SP. The consumption of electric power, vapour and water were
based on the characteristics of the Tetra Brik Aseptic – TBA filling machines available on the Brazilian industrial
equipment market. The average distribution radius for packaged milk was estimated at 200km, since
there are long life milk producers in practically all regions of the country. The final disposal considers that
post-consumer packages are recycled or landfilled. The modelling of the final degradation processes of the
packages in landfills is the same as that described previously (Mourad et al., 2008b).
2.3 Reverse logistic chain and recycling modelling
The high quality of the fibres contained in the post-consumer packages turns this waste material into excellent
raw material for the corrugated paperboard sector. The recycling of these requires hydropulpers specifically
designed for this particular purpose. The machine separates cellulose fibres from a mixed material
made up of aluminium and polyethylene and recovers around 90% of the total fibre content. The mixed material
is partially used to manufacture plates and tiles after previous milling and subsequent hot-pressing
(Zuben, 2006) and partially used to recover aluminium and produces paraffin using a plasma process
(Szente, 1997).
Using the principles of ISO 14041 and ISO/TR 14049, data from the reverse logistic chain including the
recycling processes were collected and an open-loop with closed-loop recycling procedure with expanded
system boundaries was used to model the system.
Aseptic packages are collected post-consumption and undergo the first process of recovery of cellulose fibers
made by Klabin Company in Piracicaba. This generates polyethylene and aluminum residue (PE/Al).
To model this stage, a hybrid inventory on fiber recovery was built from the data of power consumption provided
by Klabin, from data on process yield provided by Tetra Pak relating to the production process of Mercoplas
Company in Valinhos in 2011, and data on emissions published in the 2010 corporate sustainability
report of Klabin (Klabin, 2011).
Since one of the purposes of the study was to predict the main environmental and benefits accruing from
recycling post-consumer packages, the following considerations are deemed important: a) the recycled cellulose
fibres from post-consumer milk cartons were reused in the manufacture of new sleeves; b) the aluminium
obtained by the plasma process replaces primary aluminium from bauxite in the manufacturing process
of aluminium foil and c) the environmental burdens of cracking naphtha used to manufacture ethylene, later
on converted into polyethylene, were subtracted by than the paraffin obtained by the plasma process.
The credits of roof tiles co-production was done by the subtraction of the inventory of an equivalent mass of
virgin aluminium roof tiles which are replaced by the recycled one. Aluminium recovery by plasma is con-
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