Paper360 - July/August 2013 - (Page 22)

MILL WISE TISSUE Tissue Mill Dewaters Pulp with Innovative Disc Filter A PAPER360° SPECIAL REPORT T 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 solid content. 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 all times. 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. 22 Paper360º JULY/AUGUST 2013 Figure 2. New HiConBagless disc filter, installed on the stock tower of the AMS Gomà Camps tissue mill in Vila Velha de Ródão, Portugal. 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
Consolidation Watch
Association News
What’s New on

Paper360 - July/August 2013