2002 Jun JAPAN TAPPI JOURNAL

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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