European Database for Cartonboard and Carton Production 2023

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Material outputs
The main output from the paper mills is of course cartonboard. This includes about 2 kg
of cores and plugs per tonne paper, which are considered and weighed as part of the net
saleable product. The carton converting plants produce cartons. The average moisture
content of the saleable product is estimated at 8% for both virgin cartonboard and
recycled cartonboard. The main saleable by-products from the production of virgin
cartonboard production are tall oil, tall soap and turpentine. In addition, some process
residues are utilised as raw materials in other industrial processes. To aid LCA
practitioners in deciding what burdens should be considered for residues, the end-of-life
management destinations for each residue stream are indicated in the inventories.
Residues
All residues are reported as wet weight, separated according to their basic nature.
Residues are only reported where they leave the system boundaries (i.e., where they are
removed from and managed away from the site). As the mill is considered as a blackbox,
energy and emissions associated with managing residues internally (onsite) are included
within the gate-to-gate inventory data. The treatment option for residues was not
reported by all mills, so extrapolation has been necessary from those mills which did
report this information.
For the residue stream Rejects from paper for recycling, which is mainly rejects from
pulp preparation from recovered paper, it is estimated that about a third is due to
rejected materials that were associated with the previous use of the paper (for example,
staples, paper clips, tags, adhesive labels, unrecovered fibres, etc). The remaining two
thirds is material that is not in any way associated with the previous use of the paper (for
example, foreign items such as textiles, plastic packaging, glass, sand and grit, etc).
Primary fibre sludge and biological treatment sludge from wastewater treatment in mills
are mostly recycled in the process and do not leave the site. Where they are exported
from the site for treatment, they are mostly recycled (e.g. as an input into the production
of construction materials, as an input into corrugated or tissue production, or as animal
bedding), but may also be applied to land as a soil improver (landspreading), composted
or incinerated with energy recovery. No mills reported sending organic sludges to
landfill.
Ashes, green liquor sludge and lime mud are commonly reported residues from the
production of primary fibre-based paper. Ashes are predominantly recycled (as an input
into construction materials) but may also be applied to land as a soil improver
(landspreading). Green liquor dregs may also be recycled (as an input into construction
materials), although a proportion of this residue stream is currently disposed of to
ordinary landfill sites. Lime mud is predominantly applied to land as a soil improver
(landspreading).
For carton production the main waste stream is paper for recycling, which is recycled
and thus should not be called waste but recyclable material.
© RISE Research Institutes of Sweden