JAPAN
TAPPI JOURNALVol. 56, No. 6
June 2002 Abstracts
The Latest Demands for Waste Paper Treatment Technologies
Improvement of Recycling Fiber Characteristics, Appearance Quality, Further Energy
Saving and Ash Removal to use Low Price Furnish
Takeshi Kanazawa
Aikawa Iron Works Co., Ltd.
According to increase of recycling rate of waste paper as a raw material of
paper and paper board production, various technical problems have been discussed.
The latest demands relating to waste paper treatment technologies are focused
in this paper, and the typical new technologies and its relating equipment for "Improvement
of Recycling Fiber Characteristics and Appearance Quality" "Further
Energy Saving" and "Ash Removal to use Low Price Furnish" are
reported.
Improved Bleaching by Means of Fractional
Washing with MCDD Washers
Tamio Fukuzawa, Kanji Hagiwara and Chiaki Kawakami
Andritz K. K.
In2001, two large fiberline projects with a capacity of2000ADMT/D were started
up in Scandinavia. These fiberline projects employed only MCDD Washers as washing
equipment from the screen room through the ECF bleach system.
DD Washers enable the fiberline to implement highly effective fractional washing
throughout the whole brownstock wash and bleach process. The DD washer can divide
the filtrate into dirtier and cleaner filtrates. The primary filtrate from the
DD washer contains more COD and transition metals. The secondary filtrate contains
less COD and less dry solids. By means of fractional washing and filtrate circulation
with primary and secondary filtrates, the organic and inorganic substance profiles
in the fiberline process can be maintained at a lower level. Unlike the high
consistency pulping process, the processes with MCDD washers operate in the medium
consistency between the washing stage and the reactors. Therefore, filtrates
are not required to recycle back for pulp dilution before the reactors, which
prevents inorganic and organic substance build-up during the process. Due to
fractional washing and MC pulping process with MCDD washers, bleaching chemicals
can be saved and the risk of scale problems can be minimized.
Optimization and Control of Hydrogen Peroxide Bleaching
Bertil Olsson
BTG Pulp & Paper Sensors ABHydrogen peroxide bleaching is nowadays used
not only for mechanical pulp but also for chemical pulp in delignifying OP- or
PO-stages (the notification depends of if oxygen or peroxide is the dominating
one).
The method discussed in this paper is primarily developed for bleaching of mechanical
pulp, but is in principal applicable also for bleaching of chemical pulp.
If the bleaching is carefully optimized with respect to total alkali, the brightness
will be dependent on the peroxide consumption.
The peroxide consumption is basically a function of pulp consistency and reaction
time during bleaching. Mathematical models developed by Dr. Moldenius for hydrogen
peroxide can be used for both one- and two-stage bleach plants.
In both cases a system with recycling of residual peroxide is used and compensating
the flow of fresh peroxide to obtain a constant feed into the bleach tower.
This requires an accurate measurement of the total amount of residual peroxide
going back to the input of the bleaching tower.For this purpose, the analyzer
RPA-5000 is used. The function of this analyzer will be presented in the beginning
of this paper.
Paper Strength Agents for Paper Board The Effect of Paper Strength Agents in
the Highly-Closed System
Yuichi Hayashida
Research & Development Division, Harima Chemicals, Inc.
Recent paper industry makes every effort to improve the productivity and toreducethe
environmental loading by using new paper machines and waste paper as raw materials
and recycling the water used for the papermaking system.
However such a situation causes the rising of the electric conductivity, which
makes it difficult to get the effective performance for paper strength agents.
In this paper, we report that the effect of various dry strength agents which
can demonstrate effectively in such a worse condition.
Keywords ; paper strength agent , paper board , highly-closed system
Embedded Control Solutions
A New Approach To Paper Machine Controls That Improves Process Performance and
Product Quality
Hideomi Uchikawa and Jiro Isobe
Voith Paper Automation Japan Ltd.
QCS (Quality Control System) and CD actuator suppliers have been focused on
providing solutions for the existing paper machine market for the last 30 years.
These systems have proved to be highly effective at reducing MD and CD variations,
resulting in significant increases in production, savings in raw material and
energy, and improvements in sheet quality. Almost all paper machines are now
equipped with QCS and CD actuator systems. A closer examination of QCS and CD
actuator systems reveals their past and present limitations.
Applications of Robot Technology to the Paper Making Industry
Koichi Kato
Marol Co., Ltd.
Marol Co., Ltd.; well known for the manufacturer of Marol Brand hydraulic steering
systems, auto-pilot and engine remote control systems for marine use, also designs
and manufactures special purpose robots for industrial use. The company introduces
three of their custom applications for the paper making industry.
@ Palletizing Robot for Handling Carbon-less Duplicating Paper Rolls
This was developed to grip the outside of the roll efficiently without any transference
and to handle rolls of different sizes and weights at random.
A Custom Designed Automatic Grinder/Cleaner for Backing Roll of Existing Coater
This was developed to clean the surface and remove scratches from Backing Roll.
The device can be operated during operation and the surface of the roll can be
kept clean as required. The device has functional flexibility so it can be operated
under various conditions.
B Custom Designed Automatic Grinder/Cleaner for Heat Roll of Existing Soft Calendar
Researching various materials led to the development of this grinder that can
withstand heat and grind the roll to remove contaminant and finish the roll to
the required surface roughness. The device can be operated during operation and
the surface of the roll can be kept clean as required. The device has functional
flexibility so it can be operated under various conditions.
New Development of QCS Integrated with Machine Monitoring System
Nakano Reijiro
Sales Development Dept. Honeywell K.K.
To remain profitable, today’s papermakers must increase their machine speed
and efficiency, while maintaining a high-quality and uniform product. Often times,
however, faster speeds result in more frequent web breaks and also in more short-term
quality variations. The Honeywell-Measurex TMMS (Total Machine Monitoring System)
Product Quality Monitoring application module uses parallel processing to continuously
and simultaneously measure the machine direction sheet quality variations from
the product scanner. And WMS (Web Monitoring System) includes a set of high-speed
video cameras positioned along the machine to continuously monitor the web.
Typically rotating components such as fan pumps, screens, Calender rolls, Press
rolls and felts causes paper quality short-term variations. Feedback from TMMS
is used to increase machine runnability and efficiency by providing information
required for decisions to adjust felts, change press loadings, and remove, repair
or grind rolls, and adjust stock approach components. With the resulting set
of high-resolution pictures of the web break from WMS, operators can focus on
the specific problems which cause web break, and then make the necessary changes
in machine operation to optimize paper machine performance and efficiency.
The Honeywell-Measurex new QCS (Da Vinci) successfully integrated with TMMS
and WMS will supply new features of total machine diagnostics as well as CD and
MD quality controls to keep maximum efficiency of the paper machine.
Development of Automatic Watermark Drawing with Computer Systems
Kimio Hiyoshi and Katsumi Takada
Fuji Industrial Research Institute of Shizuoka Prefecture
Toshiyuki Onoda
Sanokikai Co., Ltd.
Katumi Kuboshima , Hiroshi Haneda and Masamichi Toyofuku
Specialists Community in Shizuoka
We previously reported that we had drawn directly watermark on cylinder paper
machines. But the following problems were arisen .
・It is difficult to remove the drawing materials that were seeped into the inside
of cylinder paper machines.
・The watermark was removed by organic solvent.
・There is big risk if we draw watermark on cylinder paper machine.
Therefore,we investigated watermark that the method of drawing on transfer paper.
The following results were arisen.
・The new system is more simple than that of last year.
・It is possible to control the line of watermark by the velocity of drawing and
the shape of the pen.
・The watermark of transfer paper is transcribed to the cylinder paper machine
by the flatiron .
・New removal liquid of watermark was invented.
・The removal liquid is aqueous solution and doesn't harm for our health.
We were able to use the cylinder cover of the watermark repeatedly.
The Maintenance Management System "eHOZEN"
Masami Tabuse
Yokogawa Electric Corpolation
The package software eHOZEN had been developed to support the plant maintenance
work for production plants and equipments. The plant maintenance management system
manages various informations such as the equipment database that defines equipment
specifications and also the historical database that includes maintenance and
fault information. The plant maintenance management system requires to support
reliable maintenance management information and to improve maintenance performance
and maintenance technologies. Yokogawa Electric Corporation and System Plaza
Inc. developed the new product "eHOZEN" that was redesigned the functionalities
from the old version of Client/Server configured plant maintenance management
system and added the Web capabilities. This paper shows the features and functions
of new "eHOZEN" and includes examples of performance improvement process
of maintenance management work by applying the plant maintenance information
management system.
New Technology for Slimecontrol
Takumi Sugi and Taro Iizumi
Kurita Water Industries Ltd.
The trend in paper making to use more recycled fiber in the furnish, maintain
the pH of papermachine at neutral, reduce fresh water consumption. These changes
accelerate the slime problems in the paper making propcess. Under these circumstances,
new technologies for slime control were developed.
New inorganic slime control agent is more effective than the organic agent like
DBNPA. New monitorng tool and the identification method of microorganisms used
DNA are developed to optimize the slime cntrol program in paper mill.
These techniques ensure that the greatest slime control effect is achieved at
minimum cost.
FMT-IJ: Marketable Composite of Calcium Carbonate and Silica Directed for the
Inkjet Industry.
Uchiyama Hirotaka
Fimatec, Ltd.
Inkjet printers are widely used in the world today because of the ease of printing
in full color. With the increasing ability of everyone to access the Internet,
use digital cameras, etc… The demand for inkjet printers is on the rise.
To achieve good color print quality, fine quality inkjet paper is a necessity.
Presently, inkjet paper is commonly coated with silica. Silica’s characteristics
include: high brightness, good ink absorption, and good color appearance. On
the other hand, the disadvantages include 1) difficulty to produce the coating
with a high solid content percent slurry and 2) the difficulty in handling of
the raw material. Accordingly, the disadvantages of using silica result in increased
costs.
To solve these problems, FIMATEC has developed an improved wet ground calcium
carbonate (WGCC). This improved WGCC has a higher brightness, lower viscosity,
higher solid concentration and good cost performance.
FIMATEC has optimized the improved WGCC’s particle size distribution and modified
its surface with specific cationic polymers to achieve better inkjet printability.
FIMATEC has incorporated both the improved WGCC and silica to produce FMT-IJ.
FMT-IJ has the beneficial characteristics of both GCC and silica, therefore leading
to higher brightness, higher solid concentration, lower viscosity and good color
appearance. Additionally, FMT-IJ is also advantageous in that it requires less
binder than the counterpart silica slurry.
Present Status and Prospect of Pulp and Paper Industries in Thailand Structural
Framework and Activities of Pulp and Paper Companies in Thailand (Part 1)
Yoshinari Kobayashi
Dr. Kobayashi Engineering Consultant Office
In the past two decades since my first stay in Thailand in the 70s, the structure
and raw materials of pulp and paper industries in this country have drastically
changed. In the 70-80s the Thai industries were based on non-woods, i.e., sugarcane
bagasse, bamboo, kenaf and rice straw. After the high economic growth period
in the late 80s, the industries were converted into eucalyptus-based modernized
ones. The overall paper production capacity was annually 3.65million tons and
the consumption amount was around 2 million tons, which indicated that the country
intended paper export orientation. Once the industries were mainly occupied by
subsidiary companies of Siam Cement Conglomerate, but new comers, such as Phoenix
Pulp and Paper Co., Indian-technologically-assisted company, and Advance Agro
Co. belonging to Soon Hua Seng Conglomerate have entered in these industries
in the late 80s and early 90s. Japanese paper companies which established mills
in Thailand were also described.
Sectioning Techniques of Paper for Observation and Analysis by Using OM, SEM
and EPMA
(2)Sectioning Techniques for Scanning Electron Microscopy and Electron Probe
Microanalysis
Tadahira Hamada
In previous paper, sectioning techniques for optical microscopy were described
.In this paper, sectioning techniques for SEM and EPMA were described and a new
preparation technique for paper cross section using a focused ion beam(FIB) was
also demonstrated. Several embedding methods using epoxy resin, methacrylate
resin and so on are very effective to obtain very thin sections and to prevent
creation of artifacts in optical microscopy. But the resin embedded sections
reduce the contrast of the image and then distinct micrographs can not be obtained
in scanning electron microscopy.
Further more, for observation and analysis by SEM and EPMA, it is not necessary
to make a thin section, but to make a bulky section without damage of fine structure.
Instead of embedding the specimen before sectioning by microtome, a procedure
in which the specimen is held between two plastics films such as polyvinyl chloride
was applied and satisfactory results were obtained at comparative low magnifications
(△10,000×) for various papers except thin and porous specimen such as tissue
paper.
Recently, a focused ion beam (FBI) technique which has been used for fine processing
of semiconductor or metal was applied as an improved method for sectioning papers.
By this technique smooth and damageless cross sections of various papers could
successfully be prepared.
Changes in Crystallinity and Re-swelling Capability of Pulp Fibers by Recycling
Treatment
Khantayanuwong Somwang*, Toshiharu Enomae, Akira Isogai, and Fumihiko Onabe
Paper Science Laboratory, Department of Biomaterial Sciences,Graduate School
of Agricultural and Life Sciences, The University of Tokyo, Japan
*Present address: Faculty of Forestry, Kasetsart University, Bangkok, Thailand
An integrated technique was purposed for clarifying changes in amounts of amorphous
and crystalline regions of fibers as well as for estimating possibility of their
irreversible conversion due to recycling treatment. The crystallinity of fibers
in handsheets was moderately changed by the recycling treatment as observed by
X-ray diffractometry. Because major part of fibers consisting of the stable crystalline
region which was hardly affected by the recycling treatment, the change in crystallinity
possibly stemmed from a slight increase in crystallinity of amorphous region
of fibers during recycling. The decrease in the amount of the amorphous region
by the recycling treatment, which affects the water adsorbability of fibers,
was indirectly detected by differential scanning calorimetry. Because of the
lack of re-opening of recycled fiber lumens in a wet state, the amount of bound
water adsorbed to fiber wall substantially influenced the re-swelling capability
of recycled fibers. The loss in re-swelling capability of wet recycled fibers
was consistent with sub-morphological changes of fiber wall possibly due to the
decrease in the amount of the amorphous region. In this study, FT-Raman spectroscopy
could not detect the effect of recycling treatment on changes in amounts of amorphous
and crystalline regions of fibers.
Keywords: Amorphous region, Crystallinity, Recycling treatment, Re-swelling capability
Retention Aid Chemicals for High Speed Paper Machines
Yasuyuki Kamijo and Takanori Miyanishi
Pulp & Paper Research Laboratory, Nippon Paper Industries Co., Ltd.
Reflocculation and drainage abilities of dual component retention systems, which
consisted of coagulant and flocculant, were studied with the Photometric Dispersion
Analyzer (PDA) and the Dynamic Drainage Analyzer (DDA). The dual component retention
system was found to be superior to single polymer systems in both abilities.
It was postulated that the coagulant blocked the adsorption site of the flocculant
on the fiber surface and prevented the reconformation of the flocculant chains
onto the fiber surface under the high shear turbulence. The shorter the addition
interval between coagulant and flocculant, the higher the effectiveness of the
dual component retention system. In addition the dual component retention system
improved the paper properties. The sheet permeability increased with a decrease
of drainage time.
Keywords:Dual component retention system, Coagulant, Flocculant, Reflocculation, "Site-blocking" effect
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