|2010 October JAPAN TAPPI JOURNAL
Vol.64, No.10 Abstracts
High Performance Energy Saving Screen for Waste Paper Treatment
-MaxFlow-0, 1, 2, MaxSaver and GHC-Rotor-
Technical Department, AIKAWA IRON WORKS CO., LTD.
Technical Sales Department, AIKAWA IRON WORKS CO., LTD.
Aikawa has developed screens for years as a leader of Screen manufacturing. Maxflow Screen series is the latest outward flow screen with the technologies based on our long experience. High capacity, efficient contaminant removal, low power consumption is the concept of this Screen. This simple design is the answer from our experience to pursue optimized functionality. The combination of NW Super-2 Basket with high contaminant removal efficiency and GHC rotor which has superior vacuum efficiency in low rotating speed, enables a efficient contaminant removal and power saving. The Maxflow series could suit in any specifications and process. This paper introduces the features and report the case studies of Maxflow Screen series.
Energy Saving Report by Introduction of “Intensa Pulper”
Stock Preparation Engineering Dept., VOITH IHI Paper Technology Co., Ltd.
Pulper is one of the highest power consumption equipment among various components of secondary fiber system. Therefore increasing efficiency of a pulper which stands at the first stage of the system leads to reduction of power consumption in the whole system. VPIT’s low consistency pulper “Intensa Pulper” which received Sasaki Award last year can be directly connected to slot screen bypassing primary coase screen, thanks to its high quality comparable to outlet of coase screen with lower power consumption compared to conventional pulper. With Intensa Pulper, it is also possible to reduce power consumption significantly in secondary fiber system including auxiliaries, by simplifying the system in combination with LP Screen which can cut power consumption down to approx. 1/4 of conventional slot screen.
Here we would like to introduce the case of Nippon Daishowa Paperboard Co., Ltd., Akita Mill, who actually adopted this system and achieved huge energy saving.
Continuous Nip Profiling with Embedded Sensor Technology
William S. Butterfield
Xerium Technologies, Inc.
Press section efficiency is largely dependent upon contact uniformity in the press nip. Yet, improper cover crowns, biased loading, uneven roll cover wear and uneven fabric wear can all cause non-uniformity-leading to costly sheet breaks, reduced paper quality, increased costs and decreased roll cover or fabric life. Traditional tools used to measure nip performance require machine downtime and data extrapolation to obtain a snapshot used to forecast operating conditions. Until now, there has never been a way to reliably monitor the uniformity of the nip profile to changing machine conditions.
SMART® Technology employs a proprietary embedded sensor system to extract data from the roll cover during machine operation. For the first time, machine operators get real-time knowledge of true operating conditions. Real-time knowledge provides the ability to make on-the-run adjustments and the power to optimize production, reduce energy consumption and control costs.
High Dew Point Type of Totally Enclosed Hood System for Large & High-speed Paper Machines
Engineering Dept., Shiratori Engineering Co., Ltd.
The Paper & Pulp industry is considered as a typically huge energy consuming one and each Paper Manufacturing company has been repeating sincere efforts aiming not only improvement of their production efficiency but also higher yield of wooden fiber, recycling of used paper, better energy efficiency for their various kinds of equipment and so on.
Particularly these days, upsizing of machines is much promoted and the tendency for higher speeding with bigger width of paper is getting notable. Under such tendency, it is further requested to save the energy cost. At the same time, it became an important subject how to improve the indoor environment.
In order to respond to such new demands from the industry, we, Shiratori Engineering, has been making best effort to develop new technologies basing on both accumulated capabilities for research & development and the know-how achieved from lots of supply records.
Here, we would like to introduce you the essence of our “High Dew Point type of Totally Enclosed Hood System”.
Industrial Inkjet Printing
-Market Trends and Solutions from a Coating Pigment Supplier Perspective-
Vesa Kukkamo and Philipp Hunziker
Research & Technology Services, Omya
The business environment in digital printing is currently under rapid change. The highest growth rates are expected to be in what are traditionally offset quality markets (OQM) where the new technology industrial inkjet presses can provide offset quality printing at significantly increased outputs. In the OQM, transactional and direct mail segment is currently showing the highest potential for digital color printing. The challenge in paper selection for OQM is to find the right balance between image quality, paper handling characteristics, and costs. The state of the art coated inkjet paper cannot meet the cost requirements and hence new paper grades have to be developed. Future design of coated inkjet paper is based on CaCO3 pigment, dual-pore structure of the coating layer and absorbing base paper. The coating can be run at high solids content, which means more flexibility for the application. The binder amount is decreased to a minimum and hence the cost structure is optimized. The future coated inkjet paper has shown in industrial scale tests that it can fulfill the needs of the new business environment and therefore complements the growth of digital printing.
Factors Affecting Life of Progressing Cavity Pumps
Progressing cavity pumps in abbreviate form: PC pump (HEISHIN Ltd.'s brand name is HEISHIN NEMO pump), which belong to rotating positive displacement type, can handle various types of liquid. PC pump suck a liquid strongly and discharge it smoothly. This smooth dynamics enables PC pump to be used for liquid transferring in several industries including papermaking, food, motor and water treatment. For example, in a paper factory, PC pump is used for transferring coating color, pulp, chemical fluid and dyestuff (see the picture 1 and 2).
The factors affecting life of PC pump based on choosing a pump is described below.
Development of Highly Precise Coater Blades Formed with Chromium Plating
-New Coater Blades that Can be Make High Quality Coated Paper-
Blade Group, Nomura Plating Co., Ltd.
Newly developed coater blade having long life with good profile is presented in this paper.
Nomura Plating Co. has developed “Long life plated coater blade with special chromium surface” in 1990. Developed blades were having at least 3 times longer life compared to the blade of SK material. Since then this blades have been accepted and widely used by the customer.
In addition to the long life, our coater blade has such merit as improving surface quality of the paper and deceasing streaks due to metallic characteristics of chromium on the blade. Hence, plated blade has been well-received and widely used in many customers in the paper industry even today. However, customers requirement to reduce production cost and improve paper quality are becoming harsh year by year.
And so, we pursue a forward improvement of blade having longer life and fewer streaks and then we have successfully developed “Chromium coater blade with precisely maintained blade shape”. Longer life of this new blade has been established by increasing thickness of plating with suitable kind of chromium. And stable good profile is obtained by precisely grinding blade edge also.
Field evaluation is also presented in this paper.
HC900 Hybrid Controller
-Honeywell’s Latest Controller for Quality Control System (QCS)-
HPS Marketing & Business Development, Honeywell Japan Inc.
The Honeywell HC900 Hybrid Controller is an advanced loop and logic controller offering a modular design sized to satisfy the control and data management needs of a wide range of process equipment.
The HC900 Controller provides superior PID loop control and more robust analog processing than most logic controllers without compromising logic performance. A separate, fast scan cycle executes a rich assortment of logic and calculation function blocks. Logic blocks may also execute in the same scan with analog function blocks for time critical events. These function blocks may be fully integrated into a combined analog and logic control strategy for uncompromising control performance.
Powerful combination together with Honeywell’s performance proven control technology provides users an ideal solution for process control. Open Ethernet connectivity with Modbus TCP Protocol also allows network access using a variety of HMI/SCADA software.
New Optical Caliper
-The Innovative Measurement Solution-
P&W Solutions Dept., Yokogawa Electric Corporation
Research and Development Department, ABB Ltd.
Caliper measurement and control is a vital part of papermaking. But this measurement can be a challenge. Over the years, various mechanical and optical sensors have been invented to achieve the best combination of accuracy, no sheet damage and reliable operation.
Some caliper sensors utilize laser triangulation. There are several inherent accuracy problems in this method, one particular problem known as light penetration. Grade-dependent and process-dependent calibrations or other compensations may be required when utilizing a laser caliper sensor.
In this paper, we present a new, optical on-line measurement that measures caliper without laser triangulation, thus vastly reducing errors and provide a more reliable measurement. This new method can also detect very small scale variability of the sheet. Findings on a production paper machine will also be discussed.
A Report on the Third 2010 Japan-China Pulp and Paper Technology Exchange Symposium
The third Japan-China technical exchange, “2010 Japan-China Pulp and Paper Technical Exchange Symposium”, sponsored and arranged by Japan TAPPI and China TAPI, was held on May 17-18, 2010 at Yayoi lecture hall in department of agriculture, The University of Tokyo. It was the first holding in Japan, and, as for about 110 Chinese side participants, the Japanese side participant was about 130. For each 9, in total 18 lectures were performed in the symposium. After a symposium, the Chinese side participant visited research laboratories in Tokyo and paper mills in the Fuji district.
Relationship between Hexenuronic Acid and Brightness Reversion of ECF-bleached Hardwood Kraft Pulp (Part II)
-Mechanism of Brightness Reversion and Depressing of the Yellowing by Size-pressed Treatment-
Ayano Kawae and Yosuke Uchida*2
Advanced Technology Laboratory, Oji Paper Co., Ltd.
Yellowing of ECF (Elementally Chlorine Free) or TCF (Totally Chlorine Free) bleached pulp has became a significant problem since 1990s. It has been shown that hexenuronic acid (HexA) is a main cause, but the mechanism of the yellowing is not clear. In order to suppress the yellowing, the removal of HexA from pulp has been conducted by acid treatment, hot chlorine dioxide bleaching, ozone bleaching and others. However, they need a large amount of energy, and decrease pulp yield and strength.
In this report, mechanism of the yellowing was investigated. The results suggest that the yellowing consists of two-stage reactions. The first reaction is the hydrolysis of HexA, and the second one is the reaction of 5-formyl-2-furancarboxylic acid (FFA), which is one of hydrolytic products of HexA. Therefore, it is suggested that the yellowing can be depressed by inhibition of the reaction of FFA.
We found that low molecular weight carboxylic acids (for example, citric acid, tartaric acid and others) and polycarboxylic acid (for example, polyacrylic acid) are useful as a yellowing inhibitor. Size press coating test was carried out as one of the practical ways of adding the inhibitor to the paper. This method was effective to depress the yellowing, while maintaining physical paper properties.
Keywords: Hexenuronic acid, Brightness reversion, Yellowing, Kraft pulp, Hardwood, ECF bleaching, 5-formyl-2-furancarboxylic acid, Polycarboxylic acid, Inhibitor