JAPAN TAPPI JOURNALVol. 56, No. 8

August 2002 Abstracts


The Latest Drive and Supervisory Control System
Shigeru Sekine
Industrial Systems Engineering Department,
Toshiba GE Automation Systems Corporation

　The latest drives system for a paper machine has high speed data link with optical fiber. The various drives data can be shown on the supervisory CRT. On the other hand, Information Technology (IT) has progressing very fast. Internet connecting facilities is getting familiar. The remote maintenance system and alarm messaging system via Internet has been realized.


Sensodec6S Runnability Monitoring System
Kiyoshi Dekula
Metso Automation K.K., Paper Automation Div.

　For a number of years on-line machinery condition and runnability monitoring systems have allowed maintenance departments and paper mill operating staff to measure machinery vibration, process pulsation and paper quality in order to detect mechanical deterioration or process stability problems at an early stage. With the analysis tools built into these systems, developing problems have been averted, thereby reducing the occurrence of unscheduled downtime and improving runnability. Preventive maintenance scheduling and papermachine fabric changes have been made more proactive and effective.
　Today, industry standards for network communications and emerging industry standards for operating systems and operator interfaces are facilitating the development of millwide networks. With the adoption of these standards, the seams between process control systems, quality control, production management and information systems are dissolving. Operations, quality control, and engineering personnel are now multiple users on the same network.
　Similarly, on-line machinery condition and runnability monitoring systems are becoming an integral part of the same network. Distributed architectures and high speed communications allow maintenance and operations personnel to analyze the same process and machinery condition information.
　While general information sharing is becoming commonplace, there is a continuing need for machinery condition and runnability monitoring systems to offer their specific users more insight into the complex, dynamic area of machinery condition, process pulsation and paper quality interactions. These task-oriented systems have recently introduced new signal processing techniques and user tools to make predictive maintenance diagnosis and operator interaction more insightful and effective.


Actual Of PaperMachine Operation by PaperMachine/CoatedMachine Operetion Saport Toor
Noboru Negishi
Shinko Kagaku Co., Ltd.
Naoteke Mituishi
Wako Accutech Co., Ltd.
Youhei Shiokoshi
Nippon Paper Unitec Co., Ltd.

　It has not put to practical use that operating control is done by measuring wet paper web moisture content of each part on a paper machine, due to technically unavailable to measure moisture of each part and to less affected to web breaks with the variation of web moisture depend on decreasing open draws. While operators have the know-how to indirectly estimate web moisture from monitoring steam consumption of dryers and web runnability.
　Now, we have developed new processing technology that indicate easily the moisture content and dewatering rate/dryness after the forming section, all press nips and drying cylinders on real-time. This technology is based on: �@processing technology that can analyze drying trend at dryer section �Aavailable measuring equipment that can measure dewatering rate of individual press efficiently �Bpersonal computer which became cheaper and higher performance, etc.
　As a result of applying this technology to real time operation monitoring and operation control over one year, it has been proved to be effective for rational papermaking.
　We have commercialized this system as "MOAS" , Machine Operation Analysis System for papermaking and coating.


Color Inspection System−Introduction of Color Age System−
MakotoEndo and Hideto Matsui
Production Management Department, Vision System Division, WIS Group,
OMRON Corporation

　I’m going to introduce the effectiveness of Web Inspection System for Colored Web that is based on the experience for several years at Lintec Corporation who has introduced 4 systems earlier than others.
　Also, I’m going to introduce the ideas of improvement based on the customer’s requests, and the direction of the future trend of Web Inspection System.


Plant Information System Advantage of the Process Data in the Pulp and Paper Industry
Shizuo Itoh
Plant System Div., System Plaza Inc.

　The PI System is a set of Server and Client based software programs designed to fully automate the collection, storage and presentation of plant information. PI is frequently used as an integration and development platform for enterprise wide applications.
　PI Systems serve plant data to end users and software applications, quickly and efficiently. PI client applications enable personnel to easily implement plant and corporate initiatives such as process improvement, TQC, and predictive maintenance by unifying plant data into a single repository where any individual in a company can view and analyze the same information.
　Applications such as production planning, maintenance management, expert systems, LIMS, supply chain management systems can be integrated with PI Systems to bridge the gap between business and real-time production environments.
　The PI system from OSI Software has become one of the most successful and widely used process information management systems in the pulp and paper industry.


Introduction of "Dirtformer"- Fast and Accurate Measurement of the On-Line Dirt Count System -
Yoshiyuki Kawabata
Nomura Shoji Co., Ltd.

　DirtFormer is fully automatic system for the measurement of dirt count characteristics of recycled and chemical pulps. DirtFormer measurement is based on image analysis with a CCD-camera. Dirt is recognized using contrast: a dirts is a darker area in the sample comparing to the surrounding pulp.
　DirtFormer is based on PulpExpert Oy’s dirt detection technology, which has been widely used in PulpExpert Pulp Quality Analyzer’s DirtCount Unit, Model, which are devices for measurement of dirt count from pulp sheets.


Modern Single Drum Winders
Peter Trilling
Jagenberg Papiertechnik GmbH

　According to the demands from printing industry, paper mills are requested to ship roll products with better quality and larger size rewound rolls year by year. In order meet the demands of market, winder makers realized that they should make highly sophisticated winder with full automation. Therefore, the targets are for better quality of rewound roll and automation for saving labor cost.
　In order to achieve the target, Jagenberg developed center-winding system for obtaining better quality of rewound rolls and also completed full automation system for core feeding and taping device. Our new winder Vari-Plus is so designed that one operator can cover full operation of Vari-Plus winder.
　As to rewound roll quality, it is clear that we can obtain stress free rewound roll because of center-winding with the lowest nip pressure from main rewind drum, thus makes ideal hardness of rewound rolls.
　Besides, we can operate winder with better runnability tension regardless rewound roll hardness because we have tension isolating device between running tension and rewind tension. This makes tight tension running and soft winding at the same time, which will be applied for rewound rolls for sheeter. In addition, soft tension running and harder roll rewinding at the same time, which is applied for roll shipping. It also applied for easy break paper like thin paper winding.


Polyacrylamide-based Surface Strength Agents- Characterization of Polyacrylamide-based Surface Strength Agents -
Yumiko Nagashima
Seiko Chemical Industries Co., Ltd.

　Polyacrylamide（PAM)-based surface strength agents have been used jointly with starch or polyvinylalcohol（PVA) in the majority of cases. However，as a result of the rise in demand due to various efficiencies required for surface strength agents，PAM-based surface strength agents have been used individually. Individual use of PAM-based surface strength agents results in a couple of problems：firstly，the incompatibility with surface sizing agents；and secondly the decrease in sizing effect at high concentration coating and with large quantities of pick-up solution.
　PAM-based surface strength agents have been researched from various viewpoints，and It is confirmed that these problems are resulted from each agent inquiring into their performance and size efficacy is able to be preserved by controlling the hydrophilic ability of PAM-based surface strength agents.
　Internal bond strength is one of performances required for surface strength. Internal bond strength is required to protect the blister resistance of coat paper，and the dust from a transverse section prevention of plain paper for copy paper，and high performance paper，and what not.
　In this investigation，the penetration of PAM-based surface strength agent into base paper was examined by time-dependent attenuation of ultrasound transmission in PAM-based surface strength agent solution and researched correlation with the behavior of the internal bond strength. And the rise of the internal bond strength by surface application is effected greatly by the penetration of PAM-based surface strength agents solution into base paper. A slight difference of penetration on zero-sizing base paper has an influence on the penetration of PAM-based surface strength agents solution，and internal bond strength.


New Hofmann PAM ｢H520B｣
T. Kameoka, S. Ohyama, H. Itoh, H. Doki and T. Yodoya
Formulated Products Lab., Mitsui Chemicals, Inc.
N. Sakamoto, T. Matsubara and K. Yoshida
Specialty Resins Div.

　Mitsui Chemicals has succeeded in the development of novel type of Hofmann PAM 520B which shows 1)High paper strength, 2)High drainage, 3)High Retention, especially at relatively high pH condition like pH5.5〜pH7.5 by full use of our special polymerization technology.
　It was found that "Core-Branch structure" which can be achieved by a special branching polymerization technology gives good performance to this novel Hofmann PAM 520B. which is afforded using a unique on-line additive system "Hofmanizer System"
　By using Mitsui Chemicals’ Hofmann PAM 520B and Hofmanizer System,
a customer can
1)get better unit consumption of paper strength reagent.
2)achieve higher machine speed(〜10%) without drainage aid.
3)use cheaper pulp like OCC more.
4)save waste water treatment cost.


Optimization of Wet-end Operation by "Realizer"
Koichi Tadaki, Kenji Tsunekawa, Shuichi Arai, Masa Taniguchi
FC Department, Somar Corporation

　Neutral papermaking and high recycle fiber usage in recent years make papermaking more troublesome. Conversion of acid to neutral papermaking reduced popular use of alum. Also recycle fiber usage and worldwide concern in environmental problem brought various contaminations, anionic trash and unwanted ions in papermaking process, which would harm wet-end operation. These harmful materials could deposit on papermaking equipment, and lower machine speed, fiber retention and paper quality. As a result production rate and runnability of paper machine is affected.
　"Realizer" developed by Somar will give a solution to the problems associated with wet-end operation. The new chemical assists retention of other wet-end chemicals, thus reducing total chemical usage. It also improves drainage and fiber retention. Optimization of wet-end operation using "Realizer" can be achieved by proper selection of cationic charge, molecular weight and molecular weight distribution. It depends on stock characteristics and other chemical usage. Maximization of the effect with "Realizer" is demonstrated.


HYMO TWINS SYSTEM
Hideyuki Wakamatsu
Paper Chemical Group, Shonan Research Center, HYMO CO., LTD.

　Recently, in Japanese paper mills, the papermaking conditions have been getting worse because of higher usage of recycled paper, proceeding mill closure, alkaline paper making or an increase of wire speed.
　Under such conditions, retention aids have been required to achieve much higher performance. One of such retention aid systems is the micro-particle system using cationic PAM and inorganic substance.
　We have developed various types of dispersion polymers, which have characteristics of high molecular weight, high actives and low product viscosity.
　Furthermore we have developed a new retention system, HYMO TWINS SYSTEM, characterized by using both cationic dispersion polymer and anionic dispersion polymer.
　HYMO TWINS SYSTEM achieves higher retention and higher drainage than micro-particle systems.


Dewatering machine for paper pulp− ROTARY PRESS −
Masahiro Ide
Tomoe Engineering Co., Ltd.
Process Engineering Development Section
Machinery & Equipment Division

　"Rotary Press" which is a new rotary pressure dehydrator with an unconventional dewatering mechanism, has been developed by Fournier Industries Inc. in Canada, and is going to be imported and marketed by Tomoe Engineering Co., Ltd. in technical cooperation with the Fournier Industries. The Rotary Press, which is a well-balanced machine with high dewaterability for less operating and maintenance costs including energy consumption, has recently been finding increasingly wider applications including sewage treatment in Canada. This paper describes dewatering principles, features, and dewatering performance of the Rotary Press.


Carbonizing Process Plant for Dehydrated Pulp Sludge- CONTINUOUSE HIGH-SPEED CARBONIZING SYSTEM -
Seiki MURAOKA
Tomoe Engineering Co., Ltd.
Process Engineering Development Section
Machinery & Equipment Division

　This document is prepared to describe process theory and features for "Carbonizing Process Plant" which comprises of sludge dryer, external-heating furnace with multi-stage screw conveyors and effluent gas treatment system.
　It is emphasized that dehydrated pulp sludge should not be disposed at landfill area but reused as one of resources. As one of methodologies for resource recycle, carbonization process, which turns any sludge into carbons under low oxygen circumstance, has been applied. Dehydrated pulp sludge can be dried by the sludge dryer and then fed to the first stage of screw conveyors in the carbonization furnace. While transferring sludge through insides of the screw conveyors with firing from outside of the conveyors, "carbonization process" is proceeded under low oxygen circumstance. It is envisaged that carbons derived from any sludge would be reused.
　Tomoe Engineering Co. Ltd. has provided "Carbonization Test Plant" to study process performance including running cost, operability, controllability and maintenance


Present Status and Prospect of Pulp and Paper Industries in Thailand (Part2)
-Supply System of Pulp Woods and Research Organizations of Pulp and Paper-
Yoshinari Kobayashi
Dr. Kobayashi Engineering Consultant Office

　The shift of the policy of pulp and paper industries from non-woody raw materials such as kenaf and bagasse to wood chips accelerated plantation of eucalyptus, especially Eucalyptus camldulensis in North-East in Thailand. Phoenix Pulp and Paper Co., Ltd. switched from kenaf to eucalyptus and bamboo after several years’ operation in 1987. Advance Agro Co. belonging to Soon Hua Seng Conglomerate has entered in these industries in the late 80s and early 90s with plantation of eucalyptus in their own farmers’ network fields. In spite of strong farmers’ resistance movement against the plantation, eucalyptus plantation is gradually and steadily prevailing in North-East Area in Thailand. FAO organized a symposium to confirm scientifically the evaluation of eucalyptus plantation. The conclusive argument pro and con eucalyptus plantation provided by FAO was introduced. Finally research organizations concerning pulp and paper as well as afforestation were also mentioned.


Dioxins Levels in Chlorine Dioxide Bleaching of Hardwood Oxygen-bleached Kraft Pulp (I)
Hiroshi Ohi
Institute of Agricultural and Forest Engineering, University of Tsukuba
Shuji Hosoya and Kengo Magara
Forestry and Forest Products Research Institute

　Kraft pulp and sulfite pulp bleaching mills using chlorine, chlorine dioxide (D) and other chlorinated compounds are under surveillance of the dioxins regulation in Japan from 15 January 2000. The bleaching mills are regarded as "notified establishments" which may pollute water quality. According to it, the dioxins are composed of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar-polychlorinated biphenyl (Co-PCBs). The limit for the dioxins emissions to environmental water from the mills is 10pg-TEQWHO1998/L. The limit should be considered ten times as that of the environmental water quality level (1pg-TEQ/L). One of questions is whether water qualities of process sewers in chlorine dioxide bleaching (ECF) mills are less than the environmental water quality (1pg-TEQ/L) or not. Objectives of this study are to clarify the dioxins level of ECF mill sewers and to know more about mechanism of the dioxins formation during ECF bleaching of hardwood oxygen-bleached kraft pulp (LOKP) on a basis of the analysis level for the environmental water quality. Laboratory bleaching was carried out using a mill LOKP (kappa number 9.8), chlorine dioxide from a mill R8 generator and drink water in a laboratory high-share mixer. Active chlorine factors were in the range of 0.14-1.14. The total TEQs of pulps are less than 15ppq for both the D-treated pulps and D and alkali-extracted (E) pulps. Those of spent liquors are less than 0.0057pg-TEQ/L for both the D and E spent liquors. In all cases, 2,3,7,8-TeCDD and TeCDF were not detected.

Keywords: Dioxins, Pulp bleaching, Chlorine dioxide, Hardwood, Kraft pulp


Development of Super Water-absorbent from Cellulosic Materials (4)-Porous Structure of Water Absorbent-
Yuehua Xiao and Gyosuke Meshitsuka

　Laboratory of Wood Chemistry, Department of Biomaterial Sciences,Graduate School of Agricultural and Life Sciences, The University of Tokyo
　In this paper, porous structures of the swollen hydrogels of the cross-linked CM-LBKP were examined by solute exclusion technique. Water absorbents prepared by cross-linking of CM-LBKP with different types of polyethylene glycol diglycidyl ethers (PEGDGEs) had very porous structures. The total pore volume of cross-linked CM-LBKP up to 560 Å in width was about 100 times of that of untreated pulps. Increased amount of cross-linking agent bound to CM-LBKP not only decreased the total pore volume, but also decreased the pore size with increased contribution of small pores up to 560Å in width. Re-cross-linking of the water soluble fraction from the first cross-linking of CM-LBKP seemed to proceed more homogeneously and eventually to give more homogeneous distribution of cross-linkage. Thereby re-cross-linking products had higher water absorbency and lower water solubility.

Key words: cellulose, carboxymethyl cellulose, super water-absorbent, cross-linking, water retention value, pore size, dextran