Paper Technology International 2024 - Journal - Page 54
PAPERTECHNOLOGYINTERNATIONAL
U
Uncovering mineral recycling:
A new trend in the pulp and
paper industry
A
Luis Ferraz, Innovation Project Manager, Omya International, AG
Johannes Kritzinger, Head of Innovation & Technical Marketing Paper & Board, Omya International, AG
INTRODUCTION:
In the exploration of mineral recycling within the pulp and paper industry, this paper delves into the intricate web of waste streams
and environmental challenges stemming from pulp and paper production. Omya, with over 50 years of expertise in supplying minerals to the
paper industry, emerges as a crucial partner in the journey towards sustainability, actively seeking effective approaches to recover and reutilize minerals from diverse waste streams. From comprehensive insights into waste composition to the utilization of 昀氀y ash for pH control,
Omya’s “thinking of tomorrow” commitment to a circular economic model aims to reduce environmental impact and propel the industry
towards a sustainable future.
The pulp and paper industry is one of the largest in the
world, with annual production exceeding 400 million tons (Figure 1).
Its processes generate a vast amount of waste streams including
wastewater treatment sludges, boiler and furnace ash, lime mud,
lime slaker grits, green liquor dregs or wood processing residuals.
The composition and quantity of waste generated is largely affected
by the raw materials used in the process, the paper grades being
produced, the production process and the available treatment
technologies. Around 11 million tons of waste are estimated to be
generated by the pulp and paper industry annually in Europe and
this number is expected to grow. This waste represents a huge
environmental burden and requires appropriate management.
Nonetheless, the paper industry is considered one of the most
sustainable industries in the world and has been a pioneer in the
sustainability transition. Already in 1991, the European pulp and
paper industry had a wastepaper recycling rate above 40 % and
currently, it reaches more than 70%.
Figure 1: Paper and Board Production by region in 2021.
Adapted from CEPI statistics 2022.
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Over the years, the pulp and paper industry has conducted
and sponsored most of the research on the identi昀椀cation and
evaluation of management options for its waste. Due to the large
quantities of waste generated, the high moisture content of the
waste and the challenging composition, some recycling methods
are simply too expensive and their environmental impact uncertain.
Land昀椀lling is the most common method worldwide for the 昀椀nal
disposal of mill waste. However, environmental concerns, together
with increasing costs regarding waste management and disposal,
aligned with strong social and legislative pressure are forcing the
pulp and paper industry to look for alternative ways to handle waste
streams. The pulp and paper industry must, therefore, continue
to make progress in the transition from a linear economic model,
where “take, make, dispose” was standard practice, to a circular
economic model, aiming to become a closed cycle with a zero-waste
generation, where the utilization of virgin raw materials is reduced,
and the use of recycled resources is favored. To successfully
implement a circular economic model, where waste streams are
converted into value-added products, a deep understanding of
waste chemical and structural composition is necessary.
Omya, with more than 50 years of experience in supplying
minerals to the paper industry, has been an active and important
partner, looking for sustainable and effective approaches to recover
and re-utilize minerals from diverse waste streams. Figure 2
represents the mineral life cycle in the paper industry.
Minerals are mined at Omya quarries (a) and then
processed at Omya plants (b) into products suitable for the paper
industry (c). Here, minerals are used to produce diverse paper
products which are then sent to printing houses or converters (d).
Final paper products will then end up at the supermarket (e) where
regular daily customers can purchase them. The 昀椀nal customer will
then decide whether the paper (and containing minerals) will be
recycled (f) or not. The mineral stream coming from recycled paper
will be partially reused for the production of new paper products.
Nonetheless, a large amount of minerals is discarded in different
waste streams generated in the paper mills. The amount of waste
produced in the paper industry may be surprising for the average
person. Nonetheless, in comparison to other waste streams, for
example, sewage sludge, paper mill waste streams are almost free
of pathogens making their handling and use safer and with lower
health risks.
