TAD quality 30-35% cheaper
In October 2005, CMPC started up a new 2.75 m trim Voith machinefor
30,000 tpy of tissue in its Talagante mill in Santiago. Under
aspecial agreement with Voith , the machine was equipped with
theinnovative ATMOS development and the first run using ATMOS
was made one year after the start up of the machine. “The
purpose of theagreement is to verify the technology in a full
size commercial machine and optimize it to a commercial status,” according
to sources in CMPC.
“Up to now CMPC is looking as this
project as a technical challengeand there are no specific commercial
plans so far; any future decisions will depend on the results
that are measured after the trials (energy and chemical consumptions,
machine product stability and performance, etc),” the
sources added.
“As Latin America in general is a market
where premium productsare a small percentage, any future definition
needs to take in account thecost and performance of the end
product and there is not enough data yetin that respect. Also
the fact that energy prices have doubled in Chile in the last
two years needs to be taken into account.
”The objective
is clearly to make premium grades of tissue, since thatis what
ATMOS is designed for, as well as save fibers. According toVoith,
parameters achieved to date on towel grades made with 80% DIP,
20% softwood pulp, include a basis weight reduction from 21
g/m2 to 18g/m2, a 15% fiber saving, together with 130% higher
bulk and 90% higher absorption for the base sheet. For finished
product, there is a 23% fibersaving, with 40% higher bulk and
absorption.
At
a press conference at Tissue World in Nice, Voith ‘launched’ the
new technology which, according to the company, makes TAD qualityavailable
for 35% less in capital investment and 30% less in consumablecosts,
notably energy. “Whoever buys TAD today is making a mistake,” according
to Voith Paper’s executive chairman Hans-Peter Sollinger.
If the company’s claims for the new technology are founded,
there seems little doubt he is right.
Whereas TAD can make
tissue with double the bulk and almostdouble the absorption
capacity of traditional dry crepe, it comes with ahefty price
premium. Capital investment and running costs are at leastdouble
that of dry crepe, according to Thomas Scherb, senior managerin
Voith’s Research and Process Technology Center in Brazil.
Scherb,
who is responsible for the ATMOS project, notes that, whilein
dry crepe paper the whole sheet is pressed, in ATMOS, as in
TAD,only 25% is subject to pressing. This permits production
of the structuredtissue found in premium brands. For a comparison
of the three processes, see the diagrams on this page.
One of
the great advantages of ATMOS, according to Scherb, is that
it can produce premium tissue, with high bulk and absorption,
even usingrecycled fiber. Using 100% recycled fiber, absorption
capacity of towelgrades measured in grams of water per gram
of fiber was up to 12.5 (at 0.07 geometrical mean wet tensile/BW).
The absorption capacity range at 11-13 cm3/g, while dry crepe
is in the 6-8 range.
Speed is of course below that achieved
in dry crepe but at the samelevel or even higher than the TAD
machines. On an 18-ft Yankee witha 500ºC hood, towel grade
(21 g/m2 two-ply) ran at 1200-1400 m/min(this lower speeds
with recycled). For toilet tissue speeds of up to 1500m/min
are possible.
Production costs are one of the big plusses for
ATMOS, coming in lower than either dry crepe or premium. According
to Scherb, the costper case of TAD towel or toilet tissue is
lower than for either competitiveproduct. Any excess cost in
capital or utilities compared to dry crepe isrecouped through
lower fiber input.
BUCKMAN PARTNERSHIP
Voith has worked closely
with Buckman to develop the ATMOS concept and has named the
US company as exclusive supplier for the Yankee coating chemicals
used. The Buckman coating chemical package provides “perfect
sheet transfer and uniform adhesion to the Yankee cylinder
surface, fine-tuned creping control, thus optimum ATMOSmachine
runnability,” according
to Voith. The products will be sold under the Magnos brand
name.
TW
