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 Making Paper
& Pulp 
The “Pulping” Process

Unless you’ve seen paper being made,
it might be hard to imagine that it starts with a soup-like slurry called
pulp. And this pulp is made-up of either finely ground wood, or fibers
such as cotton. Sometimes, depending on the kind of paper being made, the
pulp might be made from a combination of both wood and fibrous plant
materials.
Of course, before paper is manufactured, the pulp
must first be produced. And pulp is what we at Cheney manufacture.
Our pulp products are made exclusively from specialty
fibers.
Every step of the pulp making process affects the
quality, color, and texture of the pulp. Which, ultimately, affects the
look and quality of the paper made from that pulp.
Selecting the Right Raw Materials
Producing a top quality pulp starts with just the right raw
materials. We spend a lot of time selecting our sources for the cotton and
other specialty fibers we use … looking for quality and
consistency.
Most of our raw materials – primarily scrap
cotton from the textile and garment industries – are waste that would
otherwise go to the landfill. So we’re obtaining quality materials, and
benefiting our environment!
We bring the raw material into
our warehouse and carefully sort it to remove any contaminants or
inconsistent material. Then, through various dry and wet processes, we
work that material into a usable pulp for paper manufacturers.
Cooking Up the Perfect
Pulp  When the cotton scrap, or other material being used, is
sorted and ready, we finely chop it, then mix it with water and chemicals,
and finally “cook” it in large vats. These cookers are computer controlled
to insure that the right amount of chemicals are used, and the material is
cooked for the right amount of time, at the right temperature and
pressure.
This process prepares the fibers for refining… the
fibers no longer look like the fabric or plant matter that went into the
cookers.
Triple Cleaning and Refining the
Pulp We now refer to this soupy mixture as the “stock” … and we
put it through a cleaning system that is the most rigorous that we know of
anywhere.
At our Cheney mill, we’ve created a triple-stage
cleaning procedure that is unique in the industry. In fact, most pulping
processes clean the pulp only once. We run banks of cleaners, set up in a
series, for each cleaning step … plus require 3 separate cleaning steps
before we finish the pulp.
We start by sending the stock
through 2 banks of forward and reverse cleaners – the first bank removing
heavy dirt and large impurities, and the second bank removing fine dirt
and shives. The accepts (that is, the pulp that passed successfully
through the cleaners) then pass through another set of cleaners, also in a
series, called gyro-cleaners. Gyrocleaners remove even finer contaminants.
The resulting pulp is the cleanest obtainable.
Only now do we
finish the pulp, bleaching and refining it into the grade of pulp
desired.
Drying and Baling the Pulp
The stock is now put
into thick sheets … drained, suctioned, and compressed to remove excess
water … then run through heated dryers. When these sheets reach 85% air
dry (or 90+% for international shipments), we cut and stack them into
bales, ready to ship.
This baled pulp is called half stock,
because it needs to be reconstituted and beaten again before it can be
made into paper.
Making Specialty Papers
When paper
manufacturers receive our shipments of pulp, they reconstitute it by
adding water, and then run it through a beater in order to completely soak
and suspend the pulp back into a slurry.
The nature of the
pulp determines the type of paper you’ll produce. For example, a bleached
cotton-rag pulp will result in a bright white paper with a rich texture
and hefty thickness. But only mildly bleached pulp, perhaps with some dyes
added, can result in an off-white or cream colored paper. In addition,
mixing in finely chopped hay, tobacco stalks, or other material will
create a paper that has random speckles in it – which is a very popular
style for stationery. But regardless of the exact style of paper that is
being produced, the actual papermaking process is very similar. It’s the
contents of the pulp that defines the paper.
Once the stock
reaches the right consistency, the liquid pulp is sprayed onto a wide mesh
belt called the fordrinier, which moves very fast … at several
hundred feet per minute. The water drips through the mesh, then is
suctioned out, leaving the fibrous stock on the belt.
Still
barely able to hold itself together, the soggy paper is smoothly
transferred from the mesh belt onto a continuous felt cloth. It passes
through rolls that compress it – like the ringer on an old-fashioned
washing machine – which squeezes more water out. The paper then travels
through a series of heated dryers.
But it’s not finished yet.
In order to effectively hold any kind of ink or laser printing, a special
smooth coating, called sizing must be applied to the paper. Finally, at
the end of the paper machine, it’s either spun onto a huge roll of paper,
or cut into flat sheets.
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