|2010 September JAPAN TAPPI JOURNAL
Vol.64, No.9 Abstracts
Improvement of Productivity and Quality by Preventing Starch Degradation at Papermaking Process
Katsuhiko Hidaka, Takumi Sugi and Hiroyuki Suzuki
Kurita Water Industries Ltd.
Amphoteric and cationic starches have several important roles for improving paper quality and productivity as wet end chemicals. Starch is also used as a surface sizing agent and a coating binder. Therefore, much starch mixes into wet end process with dry-broke. Because starch is a good nutrient, microorganisms propagate and produce amylase: starch degrading enzyme, which would degrade wet end starch, thus inhibit the functions.
We detected amylase throughout the process in some paper machines; the concentration was especially high at dry-broke with much starch. According to our lab test, it’s indicated that amylase degraded amphoteric starch and deteriorated paper quality and productivity.
As amylase spreads throughout the process with bacterial contamination, we should treat and keep cleanliness from stock system; mainly dry-broke to recovery system. “Fuzzicide®”, our inorganic biocide is the best chemicals to solve the problem because it has high bactericidal activity and durability in the process. We fed Fuzzicide® to each system, mainly coat-broke and kept cleanliness in the whole process by monitoring ORP (Oxidation Reduction Potential). In the result, amylase activity decreased considerably throughout the process.
Modification of the Existing Cooking System to COMPACT COOKINGTM Process
-Existing MCC Digester Rebuilt to COMPACT COOKINGTM in Moorim Group Donghae Pulp Co., Ltd.-
Fiber Business Line, Process Technology, Metso Paper Japan Co., Ltd.
Gook Chan Ahn and Young Mok Kim
Moorim Group Donghae Pulp Co., Ltd., Korea
In order to obtain the profit by means of improving the cooking efficiency and saving the energy consumption without increasing the production rate, No.2 continuous digester has been modified from MCC cooking to COMPACT COOKINGTM G1 in Moorim Group Donghae Pulp Co. Ltd. With this modification it was showed that increased the cooking yield about 1%, improved the viscosity of the blow pulp, and saved a certain amount of the steam consumption. In the study of No.2 digester further modified to COMPACT COOKINGTM G2 in which No.1 batch digesters are stopped and No.2 digester is increased its production rate to 1400ADt/day to keep total production rate same as before. It is showed that saving a huge amount of steam, increasing cooking yield, viscosity, brightness, and reducing reject content in the blow pulp. On the other hand, with DiConn system it is possible to run with higher blow temperature than 100oC, it results in a higher wash efficiency both in Hi-heat zone of a digester and in a PDW, produce more flash steam in the cyclone, and increase the dry solids content in black liquor to the recovery boiler. In order to optimize the energy consumption in a fiber line, it is important to confirm the heat balance from a cooking plant to a bleaching plant for using warm/hot water effectively, especially for the digester in which the flash steam don’t send to the steaming vessel.
Comprehensive Approach to Optimize Dryer Part
- From Drying Energy Saving to Sheet Stabilization -
Enerquin Air Inc.
Horikawa Engineering Works Ltd.
Dryer part of a paper machine is the area where vast amount of energy is introduced and exhaust. Paper web drying process is well known technology but it should be noted that handling this area under well managed conditions in accordance with fluctuations of production load is not easy.
Global-Analysis of dryer part under collaboration between a dryer hood supplier, Enerquin Air, and a drainage system analyzer, Thermopap, with newly developed analysis tool effectively reveals overall energy efficiency of dryer part, which offers trouble shootings, ways to energy savings and further energy management of this area. Finally, Thermopap offers on-line energy management system, TEMS.
Innovating Hybrid Cleaning System for Dryer Fabrics and Backing Rolls
m-clean papertech AB
Innovating cleaning system MultiJet®, developed by m-cealn papertech AB, Sweden is used for cleaning of paper machine fabrics and backing rolls for coating station. Since year 1995, over 200 systems have been operated worldwide. Hybrid cleaning technology with high pressure water jets, air doctors and high volume vacuum gas flow allocated upon roll, which is protected by patent worldwide, assures the perfect cleaning during production and keep the original permeability of dryer fabric through the life end.
MultiJet & Brush® is a development of the MultiJet® for on-line backing roll cleaning of coating station, integrating Ø150mm rotating brush in cleaning head. It assures the perfect cleaning without leaving any moisture streak or in any other way negatively affecting the paper quality.
Novel Concepts for Monitoring and Control of Deposits in Pulp and Paper Mills
Pulp and Paper Service Department, Katayama Nalco, Inc.
Deposit control programs in pulp and paper mills are critical for machine runnability and paper quality. Although these programs are used in most systems, the management of their performance has historically been quite poor and complicated, entailing intensive analytical work and representing, in general, a reactive approach to the problem. This paper introduces the use of online and offline monitoring tools to enable a proactive approach to deposit control. Monitoring techniques are used for program dose optimization, trial evaluation and for studying the effect of process conditions on the deposit propensity of the media. Nalco’s innovation integrates online monitoring technologies with deposit control programs to monitor and control microbiological slime, pitch and stickies, and inorganic scale. With demonstrated success in the laboratory and at the mill sites, this approach enables papermakers to optimize chemical usage, ensure deposit control program performance, improve operating efficiency and ultimately reduce total cost of operation.
Reel Optimization System (ROS)
KGK Engineering Corp.
In the paper manufacturing, the reel process is understood to be very important as it is related directly to the paper loss control at the end process in the paper machine. Recently, the Reel Optimization System (ROS) developed by Vishay Systems is evaluated in the paper industry to be the system which can not only monitor the nip load directly and control it equally in both TS and DS during the full reel process but also synchronize the primary & the secondary arms movement by the hydraulic cylinders equipped with the position controllers during the spool transportation process, then can realize to decrease the paper loss dramatically by eliminating wrinkles and air bubbles. ROS is also contributing to produce the optimum density rolls which decrease the losses, like slipping in the next re-winding process caused by not uniformed roll. We would like to introduce the proven effects of the Reel Optimization System (ROS) which has been already confirmed by European and USA paper mills.
Yield Management and SmartView Web Inspection System
Surface Inspection Systems Division, COGNEX K.K.
“SmartView” Web Inspection System (WIS) and its related technologies can help users to maximize productivity. In paper machine, “SmartView” can be used not only as a conventional WIS but also as a system monitoring paper conditions for optimizing its process. In coater and supercalender, “Line Synchronization” technology enables upstream defect information to be fed forward to value added processes. “AWA (Advanced Winder Advisor)” enables re-reeler and winder to stop automatically at accurate defect position for man-power saving and maximizing throughput. SmartView is open architecture and can provide defect and process information via OPC/ODBC to other measurement systems. For example, WIS and Web Monitoring System integration allows users to track source of defects and help them to prevent sheet break.
New Automatic Cutter for Broke Roll and Core Recycling System
Maruishi Co., Ltd.
Papermakers and converters strive to improve the quality, reliability, logistic, ergonomics, environmental sustainability and cost effectiveness. The new paper machines and converting lines gets wider and faster for each new installation with maximum automation level. To stay competitive on a global market is constant improvements and investment in new technology a must. Examples of new innovate products within core and broke roll handling equipment are; Roll cutter, CLICS inner core systems, Core groover and Core recycling systems.
The 2010 Pan Pacific Conference
-April 18-21, 2010 in Melbourne, Australia-
Yuji Matsumoto and Akira Isogaii
The University of Tokyo
Oji Paper Co., Ltd.
Nipponn Paper Industries Co., Ltd.
Hokuetsu Kishu Paper Co., Ltd.
2010 Pan Pacific Conference incorporated in 64th Appita Annual Conference (18-21 April) was held under the Appita’s auspices in Melbourne, Australia. From Japan, 17 people attended the conference from a university and company including Mr. Hasegawa, president of JAPAN TAPPI.
On behalf of JAPAN TAPPI, Mr. Toyofuku, executive director of JAPAN TAPPI and Dr. Matsumoto, Professor of The University of Tokyo attended the conference. Pan Pacific Conference is held every two years in the rotation of 8 countries of Pacific Rim. The conference was held in Korea in 2006 and in Canada in 2008.
In corporation with Appita Annual Conference in this time, 29 papers were presented as Pan Pac session and 48 papers were presented as Appita Annual session in all fields of the pulp and paper.
From Japan 8 papers presented (3 from university and 5 from company). A summary of the both conferences, Japanese presentations and other interested ones are described.
The representative from TAPPI (USA), JAPAN TAPPI, Korea TAPPI, APPITA (Australia), Taiwan TAPPI, TAPPIP (Philippines) were in the attendance at the conference, but, PAPTAC (Canada) and CTIP (Chile) were absent.
A Report on 96th PAPTAC Annual Meeting and EXFOR 2010
The 96th PAPTAC Annual Meeting and EXFOR 2010 was held in Montreal, Canada on February 2-4, 2010. The meeting had 400-500 participants and 36 exhibitors. There were 3 special business session and 86 general presentations on 13 sessions.
I participated after an interval of five years since 2005. The meeting symbolized dullness of the Canada paper industry of these days, both participants and exhibitors decreased sharply in comparison with five years ago. As I visited FPInovations (former PAPRICAN) of the Montreal suburbs after the meeting, I report it together.
Reduction of Regulated Elements Leaching from Fly Ash
Makoto Iwasaki and Kazuya Ikeshima
Pulp and Paper Research Laboratory, Oji Paper Co., Ltd.
Oji Cornstarch Co., Ltd.
Materials and Structures Laboratory, Tokyo Institute of Technology
In this study, we investigated two methodｓ to reduce the leaching amount of regulated elements (Fluorine, Boron, Chromium, Lead, Selenium, Arsenic etc) from fly ash. First method is to mix Paper sludge and Coal or Paper sludge ash as well as Coal ash. In order to control the component of fuel charging into incinerator. Second one is to control the heating temperature in the incinerator. Both methods were effective for reduction of regulated elements leaching from fly ash, which resulted in decreasing the quantity of fly ash discharged from mill as a wasted material. We assumed that CAS composed by CaO, Al2O3 and SiO2 produced during burning fuels would react or capture some of regulated elements and this phenomena could bring into decreasing the leaching amount of regulated elements from fly ash.
Keywords: fly ash, leaching, regulated element paper sludge, coal, incinerator
The Adsorption Behavior of the Dispersant Polymer on Pigment in Coating Color
Atsushi Nakamura, Kengo Yamane, Yui Kikuchi and Hiroo Kaji
Tsukuba R&D Laboratory Corporate Research Center, Mitsubishi Paper Mills Limited
Ground calcium carbonate (GCC) which is used as one of the main pigments for paper coating color, is manufactured by the following steps; “mechanical grinding of naturally occurring calcium carbonate rocks”, “dispersion in water” and “wet grinding to obtain the target size particles”. In the manufacturing process, the high consistency dispersion can increase production efficiency and improve paper quality because of reducing dryer energy consumption and inhibiting binder migration during drying process.
Poly carboxylic acid type dispersant is found to be beneficial to prepare higher consistency dispersion, however optimum condition of it has been less well understood. Since the Zeta potential of pigment particle and the determination of the dispersant adsorption amount are useful factors to investigate the dispersion condition of pigment, we measured the Zeta potentials of pigment particles in higher consistency by using colloid vibration current method zeta electrometer and the dispersant adsorption amounts by total organic carbon analyzer (TOC). In our experiment, the Zeta potentials of pigment particles were the almost same level between 10% and 50% slurry and the smaller size particles showed lower Zeta potentials because the dispersant was absorbed selectively onto smaller size particle. Not only these experimental results, but also we decided that the Zeta potential changed through the following two steps. In the first step, the Zeta potential changes dramatically by a little amount of dispersant adsorption. In the next step, the Zeta potential as the dispersant adsorption density on the pigment increases.
We also investigate the effects of solute ion species on the behavior of the dispersant. Although the adsorption amount of dispersant increased in the presence of dicationic ion species, the dispersibility of pigment decreased. The Zeta potential measurement result shows dication ion species reduce the electrostatic repulsion between dispersants on the particles and make them even harder to disperse pigments.
Keywords: calcium carbonate, dispersant, Zeta potential, total organic carbon, dicationicion