PAPER TECHNOLOGY INTERNATIONAL - Talc-Free specialty chemistry concepts for deposit, pitch and stickies control in modern pulp, paper and tissue systems. BIM Kemi - Paper Technology International 2026 - Book - Page 66

PAPER TECHNOLOGY INTERNATIONAL - Talc-Free specialty chemistry concepts for deposit, pitch and stickies control in modern pulp, paper and tissue systems. BIM Kemi

PAPERTECHNOLOGYINTERNATIONAL
This can lead to agglomeration, secondary deposition, and
downstream cleanliness problems even when early-stage control
appears satisfactory. At the same time, sustainability expectations
and regulatory developments are accelerating the search for talcfree solutions. In July 2025, the Risk Assessment Committee of the
European Chemicals Agency (ECHA) proposed to classify talc as a
potential carcinogen and as a substance causing long-term adverse
effects on the lungs. As a result, many mills are now actively
exploring alternatives that provide more robust, system-wide control
of extractives while supporting cleaner, safer and more sustainable
production.
BIM Kemi’s talc-free concept addresses these challenges
by shifting the focus to early, process-wide control of extractives,
enabling talc to be eliminated while simultaneously improving pulp
quality and extending positive effects to paper, board, and tissue
machines.
A tailored solution for each mill
Pitch is not a single substance but a complex mixture
of chemicals and lipophilic extractives whose composition and
behaviour vary widely between mills, raw materials, and process
conditions. There is no “typical pitch”, and therefore no universal
treatment strategy. Effective deposit control requires a 昀氀exible,
tailor-made approach based on a thorough understanding of both
the composition of the pitch and how these components behave to
address pitch problems in a professional way in different kinds of
mills.
BIM Kemi’s talc-free solutions are based on organic,
water-soluble, and surface-active substances developed in the
company’s own laboratory. Because process conditions and
extractive behaviour vary from mill to mill, every solution is
individually tailored. The work always begins with a thorough
assessment of the process and an analysis of where extractives
accumulate, how they behave and what types of problems they
cause. Based on this, the optimal combination of chemicals and
application points is selected. For an effective talc-free solution, this
assessment must be followed by close, continuous collaboration
between the mill and the chemical supplier, ensuring that pitch is
managed proactively and the solution is adapted to the speci昀椀c
conditions of each process.
Why go talc-free?
Operational bene昀椀ts
•
Reduced pitch and stickies deposits
•
Improved runnability and fewer web breaks
•
Cleaner fabrics and longer clothing life
Process ef昀椀ciency
•
Lower inorganic loading in the system
•
Reduced need for corrective wet-end chemistry
•
Improved process stability
Sustainability and safety
•
Reduced reliance on mined minerals
•
Improved workplace safety by eliminating talc dust
•
Better alignment with future regulatory requirements
From 昀椀bre line to 昀椀nished sheet – controlling
extractives along the entire process
A core principle for an affective deposit control is that deposit
problems must be addressed along the entire process chain. If
extractives are not properly controlled in the pulp stage, the paper or
tissue process will inevitably inherit the problem.
Changes in pH, temperature or ionic strength can cause
previously stable particles to agglomerate, forming sticky deposits
that later appear as dirt, holes, weak spots or runnability issues.
When deposit control fails, the end-product often tells the story:
visible dark specks, holes, weak spots, linting, and runnability
problems for customers. Even when paper strength and softness
targets are met, the “aesthetics of cleanliness” matter—especially in
tissue, where consumers directly handle and view the sheet.
BIM Kemi’s talc-free concepts are therefore designed to
manage extractives from the very beginning of the process and
maintain stability all the way to the 昀椀nished product. A key principle
behind BIM Kemi’s talc-free concept is that pitch and deposit
problems must be addressed as early as possible in the process.
Talc has traditionally been used as a downstream safeguard to
immobilise hydrophobic extractives once they have already entered
the system. BIM’s approach is fundamentally different: rather than
managing symptoms late in the process, the objective is to prevent
extractives from becoming problematic in the 昀椀rst place.
Early control in the pulp process – removing and stabilising
extractives
The foundation of a successful talc-free operation is laid in
the pulping and 昀椀bre line stages, where the extractive load can be
signi昀椀cantly reduced before it reaches paper or tissue production. To
enable effective control of extractives, they must be controlled at the
different stages of the pulp process.
In the digester, an additive enhances the separation of
extractives from the wood chips. During pulp washing, the chemistry
promotes ef昀椀cient removal of extractives into the water circuits and
onward to recovery.
In the oxygen stage, extractives are further detached from
the pulp 昀椀bres, reducing the overall extractive load early in the
process.
In bleaching, chemical solutions can be applied using
different mechanisms depending on the speci昀椀c risks and
conditions:
- Dispersion: extractive particles are kept separated,
preventing agglomeration and adhesion to 昀椀bres. (Image 2)
Figure 1: Dispersion.
66

Paperturn flipbook viewer