|Creative Technologies of the
Thermally Sprayed Coating, "KX ROCK", for Press Roll
Toshiro Tajiri, Nobuaki Sakoda and Susumu Arakawa
KURASHIKI BORING KIKO Co., Ltd.
Recently, the requirement of high productivity in papermaking industry
demands increasing the size and the running speed of papermaking
machine, thus press-roll in the papermaking machine requires continuous
improvement of the durability and stability.
In the past years, the press-roll replaced drastically the natural
granite stone in whole roll with an artificial ceramic coating in
the surface only. This artificial ceramic coating in the surface
requires not only good mechanical and chemical properties, such as
resistance to wear and corrosion, but also surface properties, in
which the condition of releasing paper off the roll surface, i.e.
the draw property, and without contaminations attached are important.
The "KX ROCK", which is ceramic coating by thermal spray for the
press-roll, was developed as a replacement of the granite stone roll.
The "KX ROCK" coating shows a superior draw property due to optimized
surface roughness and wettability by the coating material. Especially,
surface energy of the "KX ROCK" is higher than that of original stone
roll, which leads to a good wettability, resulting in a better paper
releasing property. And in addition, the "KX ROCK" also shows a good
wear resistance and a perfect protection of base material from corrosion.
Retrofit of the Existing PS Screens by Unique Technology
- Dramatic Energy Saving and Performance Improvement
Technical Department, Aikawa Iron Works Co., Ltd.
One of the most familiar outward flow screens in Japan is a pressure
screen that is called as PS-Screen. Using the latest screening
technology developed by Aikawa, the performance of those screens
can be dramatically improved; for instance, the specific unit power
consumption can be reduced by 75% comparing with the original PS-Screen.
This retrofit technology was conferred Sasaki prize on as the best
development machinery of this year by Japan Tappi. This report
introduces this technology.
Challenge to the Development of Bulky Paper in NPI
Nippon Paper Industries Co., Ltd.
Bulky paper is getting popular in the past ten years. If the thickness
of paper is the same, the weight of bulky paper is lighter than
conventional paper. This means that bulky paper is environmentally
friendly because of the lower amount of pulps and other energy
consumption, and is human friendly as well. Nippon Paper Industries
Co., Ltd. (NPI) has been developing and producing bulky paper ranging
from non-coated paper to coated grade by new technologies. These
new bulking technologies are based on fillers and chemicals. These
materials were not used for bulking paper in the past. NPI has
challenged and succeeded to use these new technologies. Precipitated
calcium carbonate (PCC) which has scalenohedral shape and appropriately
controlled particle size is favorable for bulky paper. Those PCCs
have been producing at mill-site plants of NPI. Chemicals for bulky
paper (bulking agents) work as blocking hydrogen bonds of fibers
and so cause the decrease of strength of paper. For this reason,
paper makers have hesitated to use these chemicals. However, NPI
has had conquered problems to use the bulking agents. With well
designed filler and bulking agent and other novel technologies,
up to 30% lighter wood free book grade can be obtained.
Quantitative Estimation of Macro Stickies in Recycled Pulps for
Pulp & Paper Laboratory, Nippon Daishowa Paperboard Co., Ltd.
It was difficult to separate macro stickies efficiently from recycled
pulp for linerboard which consists mainly of old corrugated container
and measure them accurately by image analysis method, because the
pulp contains much flakes, shives and nonsticky foreign substances
We improved the image analysis method of measuring macro stickies
content, ISO 15360-2, to apply it to the pulp. By the improved
method, macro stikies content in the pulp in treatment process
was measured and the effect of removal and dispersion of macro
stickies with equipments for screening and dispersing was estimated.
Inhibition of Yellowing of ECF Bleached Hardwood Kraft Pulp
Ayano Kawae and Yosuke Uchida
Research Development Div., Pulp & Paper Research Laboratory,
Oji Paper Co., Ltd.
The aim of this work was to inhibit the heat- and moisture- induced
yellowing of ECF bleached hard wood kraft pulp (LBKP) in acidic
paper. We have already reported that one of the derivatives of
hexenuronic acid (HexA) in LBKP, 5-formyl-2-furancarboxylic acid
(FFA), causes yellowing, and that FFA might polymerize or react
with pulp components to form new chromophoric groups1).
In this study, it was shown that the carboxylic base of FFA interacts
with that of glucuronic acid or galacturonic acid, resulting in
strong yellowing. Therefore, it seems that preventing the reaction
of carboxylic bases could be effective in suppressing this yellowing.
We have discovered that polycarboxylic acids (for example, citric
acid, tartaric acid, etc.) are useful as a yellowing inhibitor.
Excellent Printing Effect of High-quality Newsprint
Nippon Paper Industries Co., Ltd.
High quality newsprint is characterized by neutralized paper manufacturing
process and high addition of calcium carbonate. We have almost
converted to the high quality newsprint from previous product in
all mills of our company. We confirmed that operation aptitude
for print like web break and dust level is as good as the previous
product according to past market evaluation. On the other hand,
print qualities of multi color printing such as show through, tone
reproduction, color reproduction are highly evaluated compared
with the previous product. It was considered that high addition
of calcium carbonate that showed high light scattering as filler
contributed to these print qualities of multi color printing.
In this paper, characteristics and printability of the high quality
newsprint are introduced, especially the analysis result of the
mechanism that derives excellent print effect in multi color printing
than the previous product is explained.
Operational Experience of New Winder Control System
Noumachi Mill, Chuetsu Pulp & Paper Co., Ltd.
Usually, only position data are sent to the drive for stopping
winder to remove spots on the paper. Stopping position of winder
is not accurate by that way, because paper length changes on the
process, web brake shortens paper length, and also the marking
position is reversed on winder.
New Winder Control System (NWCS) solved that problems, by adding
position data on the mark, which is printed on the paper edge by
ink jet printer. The data included in the mark are read by the
camera on winder, and control signal based on the data are sent
to the drive. The stopping position is very accurate, because the
position data in the controller are always refreshed by the mark.
This is really useful system, and will be quite popular system
in near future.
Operational Experience of the Biomass Boiler
Power Section Tokai Pulp & Paper Co., Ltd.
Tokai Pulp Ltd sets up a mill at Shimada city located almost middle
in Shizuoka prefecture. This Shimada Mill reaches 100th anniversary
in next year and manufactures paper and pulp mainly. Much electric
power and steam is necessary for the manufacturing process of paper & pulp.
The necessary electric power was generated at its own power plants;
a hydroelectric power plant and thermal power plants and it bought
the shortage of it from Chubu Electric Power Co., so far. The steam
was generated by its own some boilers; heavy oil fired boiler,
soda recovery boiler and waste fired boiler, so far.
We planed biomass boiler power plant in order to reduce a mount
of exhaust CO2 and a cost of energy among the social trend to stop
green house effect and to realize Society with an Environmentally-Sound
Material Cycle. We started to construct No.11 Boiler/ No.5 steam
turbine generation plant whose fuels are wood biomass and RPF at
May in 2005, completed it at January in 2006. The introduction
of this plant realized the conversion from fossil fuels to biomass
fuels and can achieve the initial purpose.
In the report, we describe the outline of biomass boiler plant
operated from February in 2006 and the operational experience.
Breeding Strategy for the Pulp Quality Improvement in Eucalyptus
Forestry Research Institute, Research & Development Division,
Oji Paper Co. Ltd.
The Eucalyptus species are widely distributed in the temperate
zone in the southern hemisphere and used as a raw material of pulp
in Asian-Oceania region. The paper manufacturing industry has particularly
high expectations to this tree because it has superior growth property
and pulp quality. Since 1991, Oji Paper has been advancing the
overseas forest plantation business for securing the forest resource
and to protect the environment.
Forestry Research Institute of Oji Paper has been studying the
improvement of the productivity of Eucalyptus plantation in Australia.
We have already isolated a lots of plus tree candidates which were
selected by growth characteristics (height, diameter, etc.) from
several plantation sites. We carried out the wood quality analysis
of the candidates. The results of the analysis showed that there
were great differences of basic density and pulp yields among the
candidates, and suggested that it is very important to improve
not only growth but also wood quality for the plantation business
and paper manufacturing. Therefore, we have been progressing the
Eucalyptus breeding project to improve the wood quality of the
candidates. Our breeding project has two approaches. One is the
conventional breeding method and the another is the molecular breeding
method using the regulatory genes of wood quality. We report our
current status of the project.
The Approach for No Manual Sorting System
Hokuetsu Kamiseisen Co., Ltd.
A sheet finishing process is still underdeveloped compared to
developed large scale and well controlled paper manufacturing process.
it needs many skilled employees who work on manual inspection and
sorting. Hokuetsu Kamiseisen Co., Ltd. operates wrapping on rolls,
sheeting and sheet finishing process in Hokuetsu Paper Mills, Ltd.
Niigata Mill and has plugged away at labor-saving through not only
automatic equipment but also awareness reform that called "quality
verification activity between processes".
This report is focused on the labor-saving history, especially
"the quality verification activity" is described. This activity
is extremely successful with the labor-saving and the re-inspection
and resort worked by many skilled sorter are basically abolished.