Paper360 - July/August 2013 - (Page 22)
Tissue Mill Dewaters Pulp
with Innovative Disc Filter
A PAPER360° SPECIAL REPORT
hanks to the installation of a
new disc filter, the AMS Gomà
Camps tissue mill in Portugal
is able to reduce its use of standard pulp bales. Today’s raw
material—bleached pulp suspension—is now thickened by the filter and
directly transported to the tissue machine’s
stock preparation unit. The installation saves
energy as well as money.
The AMS Gomà Camps tissue mill which
opened in Vila Velha de Ródão, Portugal, in
2009, had an immediate need for a compact,
flexible and reliable machine for dewatering the pulp, which at the same time had
to ensure a fi ltrate quality of under 50 ppm
Dewatering high freeness virgin pulps
using disc filters has always been a challenge.
The rapidly dewatering and strongly flocculating virgin pulp makes a safe pulp discharge
difficult, whereas severe thickening in the
vat might indeed threaten the integrity of
the whole machine. With the introduction of
the HiConBagless disc filter from Voith, these
problems are now in the past. Installation of
the disc filter allows AMS Gomà Camps a high
level of flexibility so that without mechanical
alterations to the disc filters, the mill can now
vary its production from at least 25 metric
tons per day to up to 150 tons per day.
The HiConBagless even handles the
switch between the pulp grades of short fiber
eucalyptus and long fiber Portuguese pine.
Future production increases are also possible
so that up to 250 tons per day can be processed. The clear filtrate produced by the disc
fi lter has a solid content of only 20-25 ppm.
This fi ltrate is recycled in order to pick up
new, fresh fibers for the tissue machine—and
the loop is closed.
In the new HiConBagless disc fi lter, the
trouble-free operation of the disc fi lter is
taken a step further by the help of a guiding
feature for the Bagless discs. Low-friction
guiding blocks located at the periphery of the
discs travel through a track in the vat. A collision between sectors and chutes at elevated
consistencies in the vat is now avoided at
To enhance the performance of the
machine at increased feed consistency, a
Figure 1. The pulp suspension thickened by the new HiConBagless disc filter is transported to the
tissue machine. The clear filtrate is fed back into the circuit to pick up new pulp for tissue production.
Figure 2. New HiConBagless disc filter,
installed on the stock tower of the AMS
Gomà Camps tissue mill in Vila Velha de
special HiCon version of the Bagless sectors
has been developed. These sectors promote
a targeted agitation of the fiber suspension.
In combination with the corrugated stainless steel surface of the Bagless, the elevated
forces exerted by the pulp do not jeopardize
the operating lifetime of discs. The HiCon
can also be installed as an upgrade-kit on
existing disc fi lters in combination with the
Bagless discs. This is a particularly attractive
way to increase capacity of the machine by up
to 30 percent higher capacity in some cases.
“Thanks to the good cooperation with the
Voith team, all the installation goals were
met on time,” said José Miranda, General
Manager of AMS Gomà Camps. “Compared
to a conventional virgin pulp bales pulping
system, the energy savings achieved in processing and pre-thickening of a pulp suspension with the HiConBagless disc fi lter is
approximately 30 percent.”
Table of Contents for the Digital Edition of Paper360 - July/August 2013
Over the Wire . . . News Summary
Ready for Print 2.0?
Eldorado Brasil Begins Operations in the Pulp Industry
Newark’s Frank Papa on Leadership and Innovation
Tissue Mill Dewaters Pulp with Innovative Disc Filter
TAPPI Journal Summaries
Next Generation Enzymes for the Paper and Pulp Industry
The Best Resources for Your Best Resources
What’s New on Paper360.org
Paper360 - July/August 2013