Turning the page to profitability - Paper Technology International 2023 - Paper Technology International 2023 - Flipbook - Page 106

Turning the page to profitability - Paper Technology International 2023

PAPERTECHNOLOGYINTERNATIONAL Turning the page to profitability - Paper Technology International 2023
Enzymatic fiber modification is largely based on
endoglucanases, which are cellulase enzymes. They act on paper
fibers resulting in the formation of fine fibrils that increase inter-fiber
bonding potential. This improves refinability and the strengthening
potential of the fibers, which enhances paper and board’s strength
and structure.
The result is a significant improvement in paper and board
structure and strength. Papermakers can take advantage of this in
a number of ways — saving on fiber costs; reducing the amount of
energy required for refining or drying; reducing the use of chemical
strengthening agents; and producing a higher quality end product
in a more sustainable manner. This process, which is already
established practice in tissue and towel manufacturing, is being
increasingly applied in the printing and packaging segments.
Implementing a plug-and-play solution
In a case study by Novozymes, one of the world leaders in
bio innovation, a mono-component cellulase product was tested in a
full-scale implementation in the printing and writing segment.
Industry experts performed an analysis to find the application
point in the mill that would provide the greatest potential benefits.
The trial was then implemented with minimal disruption and risk to
mill operations.
The process was very straightforward, with no adjustments
to existing mill operations and no CAPEX investment. All that was
required was the enzyme product itself and dosing pumps to add the
product to the application point.
Enzyme application experts provided guidance throughout
the process and monitored conditions to ensure optimal results.
Economic—and environmental—sustainability for paper mills
The printing and writing case study overwhelmingly
demonstrated the benefits of enzymatic fiber modification for the
pulp and paper industry. The mill saw a significant ROI in terms
of fiber savings, increased production, improved refining, and
increased bandwidth and budget for new product development.
The paper mill reported a tensile strength increase of 16
percent and a 17 percent increase in internal bond strength. As a
result, the solution delivered almost immediate short-term savings,
cutting the energy required for refining by 50 percent.
For a European paper mill that refines 200,000 tons per
year (TPY) of bleached pulp with 80 percent hardwood and 20
percent softwood, this is an energy reduction of 20 kilowatt-hour
per ton (kWh/t) and 45 kWh/t respectively, a total savings of 5,000
megawatt-hour (MWh)/year. Based on the 2021 average European
Union energy cost of 0.1445 €/kWh, this represents a value of 3.5
€/ton or 720,000 €/year. That’s the equivalent of importing about
$130,000 USD less natural gas per year2.
The mill in the case study also noted that, by shrinking their
energy footprint, mono-component enzymatic fiber modification also
significantly reduced the mills’ environmental impact. The immediate
effect is the ability to get the most out of every tree harvested
by producing more from less. Lower refining energy and steam
consumption resulted in an annual greenhouse gas reduction of
1,100 tons of carbon dioxide (CO2)3 — an effect equal to taking 470
cars off the road.
Expanding the application of enzymes to other stages of
the pulp and paper process can potentially move mills even further
toward their environmental goals by displacing or removing various
chemicals in the pulp mill, bleach plant, and stock preparation.
Additionally, enzymes used in the dewatering process can also
allow mills to use more recycled materials and less virgin fiber by
improving the dewaterability.
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Getting the most from the mill…and from every tree
As growing demand, increasing costs, and tighter
environmental regulations make even razor-thin margins nearly
impossible to maintain, papermakers need to explore alternatives
that move beyond the diminishing returns of traditional mechanical
and chemical optimization methods.
With minimal operational adjustment and no additional
CAPEX investment, paper mills can use enzymes to lower operating
costs through significant energy savings in the refining process.
They reduce materials cost by maximizing the papermaking
potential from existing wood and pulp. And they potentially reduce
or eliminate the cost of strengthening agents and other chemical
products used throughout the papermaking process.
From an environmental standpoint, better utilization of
existing fiber both reduces the pressure on forests and lowers the
amount of wood or fiber needed for each ton of product. Additionally,
adding strengthening potential to fibers with enzymes allows for
the final product to be lighter without compromising strength. That
means that, in addition to lowering the CO2 output of the mill itself,
enzymes contribute to lowering CO2 in the transport sector in a
time of rapid e-commerce growth. And, by reducing the need for
chemicals, enzymes bring mills one step closer to meeting their
sustainability goals. All without added investment in environmental
initiatives.
A huge variety of industries worldwide — from agriculture,
animal production, and biofuels to household care, textiles, baking,
brewing, fermenting and pharmaceuticals — are already taking
advantage of the added value, cost-savings and environmental
advantages of enzymes. As they strive to make their margins in a
world where demand is outstripping supply, enzymes offer a proven
means by which pulp and paper manufacturers can meet demands
in a cost-effective, sustainable way and regain a competitive edge.
Figure 3: Enzyme
Notes
1
2
3
2020 Annual retail Trade Survey (ARTS) Tables
https://www.census.gov/programs-surveys/arts/data/tables.html
Based on a natural gas price of $7.84 USD/MMBtu (09/05/2022)
Based on the 2020 EU average of 230 grams of CO2/kWh grid
mix, including the carbon footprint of the enzyme

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