JAPAN TAPPI JOURNALVol.
December 2004 Abstracts
a Bright Future in Papermaking
Metso Paper, Inc.
In many old line industries investments have slowed
down due to slow payoffs. This trend is turning much of traditional
into a technological backwater. In a world where productivity and
related investments are key, sluggish productivity improvements result
in a vicious cycle with little prospects for big returns. Only proactive
productivity development, product quality improvements or new business
approaches will lead to long-term success in the paper industry.
addition to the productivity challenge there is the anticipated threat
of electronic media. But the worldwide per capita consumption
of paper is still increasing. It is predicted that worldwide paper
consumption will continue to grow at 2%-4% annually.
consumption of paper is driven by a thirst for knowledge, and so
long as the cost of paper is competitive relative to competing
media, its versatility in terms of accessibility will secure it a
strong market position long into the future.
Profiling Systems to Existing Headboxes
-Results from the First BTF
Dilution Control System in Japan-
Mechanical Designer Paper Machinery, Kawanoe Zoki Co.,
In July 2003, a BTF Central Distributor, with automatic dilution
control, was installed on the existing Escher Wyss headbox on paper
machine No 3 at Marusumi Paper Co., Ltd. Kawanoe mill.
The goal of
this project was to improve the CD basis weight profile, to reduce
the grade change time and to improve the sheet edge quality
for producing wider sheet.
All grades produced so far are running
around 50% or better than the 2-sigmas that were previously (before
BTF installation) achievable.
The grade changes are much faster and are now done within five minutes.
The basis weight profile is no longer an issue during grade changes.
the sheet edge quality was improved so that 30mm wider sheet can
The Latest Headboxes for Board and Packaging Grades
Voith IHI Paper Technology Co., Ltd.
The one of the most important
parameter for product quality in board and packaging (B&P) grade
is still its strength basically. But new trend in B&P grade is
reduction of basis weight, and requirement in product is not only
its strength but also the fineness of the
surface quality, which influence printability. Due to these tendencies,
better quality and higher performance must be required for the headboxes
for B&P grade compared with those in the past. VOITH Paper had
developed MasterJet headboxes, based on the well-known technology
of the high-turbulence W-type headbox and ModuleJet dilution control,
to meet the higher demands from the paper industry. On the other
hand, VOITH Paper also considers economical solutions for the B&P
SUCCESS FORMER and Its Application in Overseas
Masahito Mukai and
Paper Machinery Engineering Dept., Kobayashi Engineering
The Pulp/Paper Industry is growing more intense in competition
globally. Under the Present circumstances, “Success Former” is the
very effective machine to achieve the Purpose of improving both productivity
and quality of paperboard. In this thesis, we would like to introduce
the structure and characteristic of it, also explain how it has been
developed in such a high growth market like China.
is designed based on Kobayashi’s original ideas, to realize excellent
formation and superior quality for Multi-layer
paperboard. We have many achievements for producing various kinds
of paperboard in domestic and abroad markets. The most remarkable
point is “Success Former” has obtained a high evaluation in China
of late. We have exported 2 complete units to China in recent 3 years.
Both of them had smooth start-up, which truly satisfied our customers
with the high advantage to their investment. Here, we will introduce
Theory and Practice for Formation
Metso-SHI Co., Ltd.
Michael Odell and Pekka Pakarinen
Mestp Paper, Inc., Jyvaskyla , Finland
This paper is an overview of
the theory and practice of improving formation. The aim is to provide
background information for mill
personnel to understand the basic mechanism of formation improvement
and how these mechanisms can be controlled in practice. The scope
of the paper is mostly related to paper grades and concerns all headbox
and forming section types. There is a lot of relevance in this discussion
also for board grades although the emphasis is primarily on paper.
principles of how formation is influenced by fibre concentration,
shear, turbulence, flow elongation and drainage are explained. In
the furnish and stock preparation area the influences of fibre properties,
refining, wet end chemistry and formation improving additives are
discussed. There is a section on formation measurement intended to
brief the reader on what measuring methods are appropriate for different
uses and how new measuring methods can characterize the appearance
of formation. Formation improvement cannot be considered in isolation
from other paper properties so while formation is the main theme
of this paper the consequences of formation tuning activities on
other paper properties are also described.
The emphasis on practical
tuning in this paper is on how to optimize the headbox and former
operation. There are sections in this paper
concerned with formation fault finding, systematic tuning procedures
and strategies for routine formation control. A new formation tuning
technique based on measurement and control of Z direction formation
profile is introduced in this paper.
Latest Technology of Forming
- Bel Baie Former Upgrade with VentaShoe Technology -
Mitsubishi Heavy Industries, Ltd. Paper & Printing Machinery
Mitsubishi Heavy Industries, LTD. has developed a new technology
that combines the best aspects of roll-blade and pure blade forming.
This new technology consists of replacing the initial forming zone
with a grooved smaller radius blade design. Rework to a former and
headbox is minimal.
As in roll forming, the VentaShoeTM traps the
jet more symmetrically with a positive angle to the wires that reduces
the jet impingement
sensitivity. Reduction in jet impingement sensitivity provides easy
operation without any defects such as spotting. The blade drainage
section provides the superior formation of a traditional blade former.
are currently eleven papermachines utilizing this new technology
in the field. The first started up in North America in 2001. All
have been demonstrating many benefits in terms of paper qualities
and papermachine operation.
Shoe Press Technology for the Dewatering
of All Paper Grades
Voith IHI Paper Technology Co., Ltd.
The important technological and
economic advantages have expanded the use of shoe press technology
to dewatering of all paper products
from pulp and tissue. Whereas the development of NipcoFlex technology
began in packaging paper machines 20 years ago, this technology can
today be found in virtually all applications for the mechanical dewatering
of the paper web in new and modernized production systems. The portfolio
offers an economic solution for increasing productivity and efficiency
for any requirement, whether a rebuild or a new machine. The advantages
of shoe press technology are now also utilized in calendaring in
the paper industry.
Remodeling Shoe Press of PM10
Kasugai Mill, Oji Paper Co., Ltd.
The PM10 at Kasugai Mill, Oji Paper,
was started up in February 1991, and it has been produced wood-free
paper and coated paper.
Chiefly, remodeling shoe press installed in the third nip was achieved
continuous stability operation with design speed 1,300m/min in January
2002. In the past, there were problems of drier dryness ability shortage
and production rate restriction due to insufficient pressed. The
shoe press has brought a 4% to 8% increase in dryness compared to
roll press. After remodeling, shoe press has been evaluated at high
contribution degree to improve both paper quality and productivity
and have been considered to be indispensable equipment for quality
improvement and increased machine speed, and the production increase
plan was achieved.
In this report, it reports around the outline
of remodeling, the operation experience, and the effect of the introduction.
Improvement by Remodeling the Headbox and the On-top Former in PM7
Niigata Mill, Hokuetsu Paper Co., Ltd.
Niigata mill PM7, which started
up in 1990, produces A2/A3 coated paper with on-line coating. PM7
had quality subjects that had to
get over and the reached conclusion was that the improvement of
the base paper profile and formation were indispensable. Therefore,
remodeling of the headbox and the on-top former were carried out
in 2001. The “SymFlo-D” was adopted for the headbox that controls
the BD profile by dilution. The wire section renewed to “Duo-D
former” that achieves the remarkable formation improvement effect
by the counter blades. This report shows the overview of the equipment,
the operation and the quality improvement by the remodeling.
of Hardwood Pulp Yield in Continuous Kraft
Cooking and Estimation
of Pulp Yields (Part III)
-Pulp Yields of Isothermal Cooking with
Kraft and Polysulfide Liquors as well as Anthraquinone-
and Hiroshi Ohi
Graduate School of Life and Environment Sciences,
University of Tsukuba
The pulp yield was improved by about 4.5-5%
when polysulfide(PS) and anthraquinone (AQ) were added to the kraft
cooking liquor (white
liquor). The exchange of the black liquor with fresh white liquor
further increased the yield. The highest pulp yield was obtained
when the PS cooking liquor containing 70% of total active alkali
(AA) and 100% of AQ was used from the beginning of the reaction and
the black liquor was exchanged with fresh white liquor containing
the residual 30% of AA just after temperature reached 135℃.
was a good correlation between kraft pulp yields of a hardwood species
and the ratios of the amount of xylose to glucose (X/G ratio),
liberated by an acid hydrolysis of the pulps. However, the correlation
was dependent on raw material wood species. Therefore, it is required
in advance to establish a correlation between the yields and X/G
ratios for raw material wood species of a target pulp in order to
estimate pulp yield using X/G ratio. The X/G ratios of relatively
high yield pulps showed higher values than those expected from the
In a mill trial, the superiority of the PS-AQ ITC process
over the kraft ITC process was confirmed by examining X/G ratio of
The pulp yield in the PS-AQ ITC process was estimated at about 57.0%.
This yield is very high, which indicates that reaction conditions
of the PS-AQ ITC process are optimal.
Keywords: kraft isothermal cooking,
polysulfide, anthraquinone, carbohydrate, pulp yield, mill trial