JAPAN TAPPI JOURNAL Vol.61
No.8
August 2007 Abstracts
Press Section Rebuild and Energy Saving Press Roll
Akimine Izawa and Koshi Tanimoto
Mitsubishi Heavy Industries, Ltd.
Recently, the attempt to avoid global warming and a sudden
rise of the crude oil price push the paper industry to have the ecological
effort, such as energy saving, resource saving and high efficiency.
Thinking about such a background, MHI has developed compact type
of shoe press "Mini shoe press", of which shoe length is 30`40% of
STD shoe press and also has developed energy saving press roll, which
reduce stirring energy of internal oil.
This paper presents the feature of Mini shoe press and performance
of the first installation in Japan. And also, it presents about the
concept and effect of the energy saving press roll.
Voith Paper New Research & Development Center
- Life Cycle Partnership -
Osamu Yasui
Paper Machine Engineering Dept.CVoith IHI Paper Technology Co.,
Ltd.
During these few years several new paper machines with high speed
and large width started up around the world, and set one speed
record after another. Enough pilot machine trials during planning
such machines are very important for successful excellent paper
quality after start up. Voith Paper new research & development
center started in operation accordingly. That pilot paper machine
is consist of MasterJet II G type headbox, DuoFormer TQv, Tandem
NipcoFlex Press and Top DuoRun, and maximum operating speed is
3000 m/min.
Here we introduce this sophisticated new research & development
center, and we hope this introduction helps for customer to get
perfect solution.
Wet End Optimization
- An Ongoing Process with Extensive Benefits -
Roland Berger and Daniel Watzig
BTG M tek
Kenichi Ishihara
Spectris Co., Ltd. BTG Division
Gaining greater productivity and paper quality is a systematic
and continuous process. This statement is especially true for the
Wet End of the paper machine. Many strategic additives are introduced
to influence machine runnability and paper quality. At the same
time there are only few areas of the paper machine with less automatic
control. This paper will present two case studies of waste paper-based
newsprint machines at the Papierfabrik Palm, Eltmann mill that
led to better control in the Wet End.
The Organic Polymer Coagulant for the Elimination
of Pitch Trouble
-Stabilization of Paper Making Process by Inactivating
Micro-Pitch Particles-
Kenji Sakai, Takahiro Fujimoto, Hiroyuki Koshio and Motosuke Ono
Shonan Research Center, HYMO Corporation
In order to eliminate pitch-trouble in paper-making process, use
of coagulants is effective to reduce free pitch particles in the
process water by fixing "micro-pitch" onto pulp fibers before growing
into a large-size pitch.
In our previous report, we introduced new analysis methods, "micro-pitch
image analyzer system" and "film adhesion method", as the tools
for analysis of micro-pitches and evaluation of coagulants. The
methods showed that a coagulant having specific property reacted
with a particular type of pitches selectively, and thus a particular
coagulant should be chosen for the different types of furnish,
GP, TMP or DIP etc.
In this report, we indicate several Organic Polymer Coagulants
synthesized by controlling the charge density, the molecular weight
and the balance of hydrophilic and hydrophobic segments show different
characteristics in adsorption onto sticky-pitch, coagulation of
micro-pitches and ion-neutralization of anion trash as a pitch
control agent.
We believe that our Organic Polymer Coagulants contribute to stabilize
the paper-making process by selecting appropriate coagulant according
to the property of the furnish, a type of pitch-trouble or other
purposes.
Brightness Reversion of Eucalyptus Pulps after ECF Bleaching with
Various Sequences
Christian Blom, Jiri Basta, Magnus Bjorklund, Thomas Greschik and
Muneo Sakamoto
Eka Chemicals AB
The aim of this study was to compare different bleaching alternatives
for oxygen delignified eucalyptus aimed at a low brightness reversion.
Three eucalyptus pulps with different characteristics were included
in the study. D (OP) Dn D, D*(OP) Dn D, A*D (OP) Dn D and Z (OP)
Dn D bleaching sequences were compared, and the corresponding sequences
with a final P stage instead of a final final D stage were also
included. Brightness reversion in both dry and humid conditions
before and after beating was evaluated. Other important parameters
such as bleaching chemical demand, pulp viscosity and fiber strength
potential were also considered.
When bleaching to 90.5% ISO brightness and compared to the standard
D pre-bleaching, D* gave 5-17% savings in OXE, A*D gave 16-24%
savings, Z at a high ozone charge (about 5.0 kg/t) gave a small
saving (4%) for the traditional E. globulus pulp but increased
the OXE consumption with 13-31% for the two other pulps. A considerable
increase in chemical demand was recorded at a low ozone charge
where also the brightness target was difficult to meet. The standard
D sequence gave the highest and the Z sequence the lowest viscosity.
The standard D sequence also showed the highest fiber strength
potential measured as rewetted zero span strength at 3000 PFI revolutions,
and again the Z sequence gave the lowest value.
The different pre-bleaching alternatives gave only small differences
in dry brightness reversion and the results after beating were
different from those prior to beating. A final P stage always gave
better dry brightness reversion than a final D stage. The standard
D sequence gave higher humid brightness reversion values than the
other sequences, but modifications to the D sequence showed promising
results. Evaluation of brightness reversion in humid and dry atmospheres
gave different results and there was no general correlation between
the two evaluation methods.
Keywords: oxygen delignified, eucalyptus pulp, bleaching, ECF,
chlorine dioxide, hydrogen peroxide,
ozone, hot D stage, hot acid
stage, brightness reversion, beating, fiber strength,
viscosity,
chemical consumption, modified D stages, effluent characteristics
The Anthony-Ross Automatic Spout Cleaner
Ken Pingel and Dan Higgins
Anthony-Ross Company
Trevor Ip
Recovery Process, Northwood Pulp and Paper
Twelve years ago Anthony-Ross Company applied for and
received the patent on our first Automatic Spout Cleaner. Unlike
the original however, the Anthony-Ross Spout Cleaner in its current
form is a result of over 12-years of design evolution.
Almost without exception, each of the evolutionary steps from our
first spout cleaner to the present was a direct result of observations
and suggestions from boiler operators and maintenance staff.
Twelve years ago the criteria to a functional spout cleaner was
unknown, even to boiler operators, but with each new test, test
installation and improvement the design was refined and criterion
developed until we understood how to produce spout cleaning equipment
that would be a true asset to boiler operators without burdening
the maintenance staff.
The following is a description of the Smelt Spout Cleaner in its
current form and our patent pending solutions to reliable automatic
spout cleaning.
Synergy Effects of PCC and Pigments with High Aspect Ratio
Tatsuya Asano
IMERYS MINERALS JAPAN K.K.
Benny Hallam and Chris Nutbeem
IMERYS Pigments for Paper Europe
Conventional thinking regarding the optical characteristics
for coated paper is the design characteristics of the coating pigments
are critical. Key design characteristics are the average particle
size, the particle size distribution and the particle shape. If
these factors can be combined more effectively in the coated layer
they can give improved characteristics, namely, the diffusion of
light whereby improving opacity and improving gloss of the coating.
Optical synergy effects start to become evident through the combination
of calcium carbonate and kaolin in which the unique pigment design
of each component is different and the result is a complementary
effect on coated paper properties.
Through this research we can understand some of the synergy effects
in coated paper when blending coating PCC and high aspect ratio
kaolin. The combination of shape engineered pigments leads to synergies
that are not evident when simply using size engineered pigments.
Intelligent Sensor Management System
-Capable of Self Diagnostic-
Yasuo Watanabe
Mettler Toledo K.K.
The periodical maintenance work, for instance cleaning,
calibration and so on, is needed to get the accurate and reliable
value of the inline pH measurement. In the case of Pulp and Paper
industry, many pH loops are working in the factory and a lot of
labor power is necessary for implementation of these kinds of maintenance
works. And also sometime these maintenance works make the downtime
of process. As a result productivity is down. New generation pH
electrode which provides not only the saving labor cost, but also
reliable pH value was launched by Mettler Toledo. In this report,
the features and benefits of the new generation pH electrode are
introduced.
Prevention Control of Pest
Yoshihiro Kuroda
Research and Development, Earth Environmental Service Co.
There are 3 important activities for effective pest
control (prevention of insect contamination) in pulp and paper
factories as follows;
1) Analysis of claim from customers caused by contamination of
insects as well as detection of contamination in the factory. It
is important that they get real-time information of insect (=contaminants)
and they should identify the kinds of contaminants, and contaminated
location of processing line. Results should also be recorded, collected
and kept.
2) Collecting environmental parameters to use of real time monitoring
system indicating direction and velocity of air flow, sheet shutter
and doors opened frequency, temperature, humidity for all monitoring
points as well as the number of contaminants captured.
3) Investigation of successive data of each kind of contaminants
captured by traps and other environmental parameter in the factory.
It is important that they should find out the root of the problem
due to correlation analysis.
Trend in Mechanical Seal Technology in Pulp and Paper Plant and
Erosion Countermeasure Examples of Mechanical Seal
Hidekazu Takahashi
EAGLE INDUSTRY Co., Ltd., Seal Engineering Dept.
In a pulp and paper plant, a large number of water
pumps and various different pumps for pulp or chemicals are utilized
in the production processes from economical point of view (energy
saving, resource saving and maintenance saving) and environment
preservation point of view. Mechanical Seals are also utilized
for other rotating equipment including agitators, screens and refineries.
The Mechanical Seals for pulping is especially important. These
sometimes leak by the damages of the Seal Rings and the Mechanical
Seal Covers by the sand erosion. This text describes failure and
countermeasure examples of Mechanical Seal for pulping process.
Effect of Surface Structure on Gloss of Coated Paper
Hideyuki Mikado, Keiro Takigawa, Yukiko Suzuki and Tetsuya Hirabayashi
Pulp & Paper Research Lab., Oji Paper Co., Ltd.
Gloss of coated paper is affected by the surface shape and scattering
intensity of pigment layer. The surface shape consists of various micro-plane
slopes. Each degree of micro-plane slope is estimated by the differential value
of curved surface. Scattering intensity of pigment layer is estimated by the
pigment diameter. In this paper, we investigated surface structure of coated
papers which had various degrees of surface smoothness in order to clarify the
dominant factor of gloss of coated paper.
We found that there was a good correlation between degrees of print gloss and
differential values of printed surface. This means that print gloss is dominated
by the variety of micro-plane slopes forming the printed surface shape. We also
found that there was a good correlation between degrees of differential values
of printed surface and degrees of differential values of@unprinted surface.@This
means that the printed surface shape mainly depends on the surface shape before
printing.
Ink layer gives various affections to the surface shape of printed paper. In
regard to gloss paper including LWC, the ink layer reduces the differential value
of curved surface. The matte paper has no effect on that of curved surface. The
cast-coated paper is affected increasing the differential value of curved surface.
Therefore, as the paper surface becomes much smoother before printing, such as
cast-coated paper, the printed surface shape has much stronger influence of ink
layer.
We also found that sheet gloss was decided by differential values of the surface
shape and the diameter of pigment constituting coated layer. Therefore, we assume
that sheet gloss is dominated by the variety of micro-plane slopes on the paper
surface and scattering intensity of pigment in the coated layer.
Keywords: coated paper, print gloss, sheet gloss, micro-plane slope, differential
value, scattering,
pigment diameter, coated layer, ink layer |
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