European database for cartonboard and carton production, 2023

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The individual cartons are then stacked up and passed through to the next stage of
production, folding and gluing.
When the cartons have been cut and creased, they are moved through to the gluing line
where the cartons are folded and glued. This is done on high-speed machines that, in one
operation, fold the creases and glue the seams where necessary.
The cartons are then packed for shipment to the carton user who puts them onto their
packing line for filling.
In addition to the typical processes outlined here, additional processes may also be
required for specific design features, such as lamination, insertion of window patches,
etc.
Methodology questions
Boundaries and declared unit – cartonboard
Gate-to-gate life cycle inventories for virgin cartonboard grades and recycled
cartonboard grades are presented in the Table 2 according to the following declared unit:
one air dry tonne (1000 kg) of net saleable paper at the parent reel,
before conversion to finished products
The system boundaries of the life cycle inventories for cartonboard include all activities
within the papermill boundaries, including any integrated pulp production. Thus,
included in the inventory are all the inputs and outputs (from/to the technosphere and
from/to nature) associated with:
• Integrated pulp production from pulp wood/wood chips
• Integrated pulp production from paper for recycling
• Stock preparation, refining, and operation of the paper machine
• Drying
• Reeling and reel winding
• Supporting activities used in paper production, e.g., water and solid waste treatment,
onsite electricity and heat/steam generation.
Figure 3 summarises the system boundaries. These system boundaries are representative
of the core processes.
In cases where the mill produces and sells excess energy (e.g., electricity or steam), this
is treated as a multifunctional situation. The system provides two functions (i.e.,
cartonboard plus energy). In this case, subdivision has been applied – i.e., only the inputs
and outputs that are allocated to the paper production are reported in the life cycle
inventory.
No allocation was made to by-products such as tall oil, turpentine and wood/bark chips,
so the reported inputs and outputs include the production of these by-products.
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