2012年2月 紙パ技協誌

Vol.66, No.2 Abstracts

Operating Experience of Nantong PM1 in China

Kotaro Kisaka
Strategic Planning Dept., Technology Div., Oji Paper Co., Ltd.

 Oji paper has been progressing a project for construction of a large scale integrated pulp and paper mill in Nantong, China. Currently, first phase construction is finished, the No. 1 paper machine and coater began commercial operation, which have produced uncoated fine paper and coated paper A2 since January 2011.
  In this paper, we report on the operating experiences through to commercial operation since commissioning.

The Ultra Thin Cartridge Dual Mechanical Seal

Hidekazu Takahashi
Engineering Div., EAGLE INDUSTRY Co., Ltd.

 In a pulp & paper plant, many numbers of varieties of pumps are utilized such as water pumps, pulp pumps and chemical pumps all through the production processes from digesting to painting. Recently, a mechanical seal has been selected as a standard sealing device for such pumps. A cartridge seals are coming into wide use for work improvement, for being easy to handle and for installing correctly. We develop novel and compact ultra thin model cartridge seal that uses 2 mechanical seals. And then these seals are contributing on the trust inclination by water saving and energy conservation, backup function in a pulp & paper plant.

Automatic Steam Control System with the Maximum Boiler Efficiency under Any Operating Condition

Masahiko Murakami and Tomohiro Okubo
Miura Co., Ltd. Ishinomaki Mill

  MIURA as a leading manufacturer of small once-through boilers has adopted “Plant infrastructure total solution” as a slogan and is promoting various eco-friendly proposal activities through water treatment devices for industrial water and compressors using in-plant process steam, and so on. This paper explains following technologies;
・Small once-through boilers with very high efficiency and multiple boiler installation system by using each boiler’s most efficient operation point

Outline, Operational Experiences and Development of the Vertical Separator Washer “Vertical Z”

Minoru Ishikawa, Takefumi Ide and Kiyoshi Yoda

  In Japan where we cannot expect much natural resources, the utilization of waste paper is quite active and various kinds of technology have been developed. On the other hand, the necessity of recycling the resources is widely urged due to the threat of global warming. Under the circumstances, the utilization of waste paper has been accelerated and now further advanced disintegrating technology to enable the usage of the waste paper which has been abandoned as waste before is keenly expected.
  We, Taizen, have been developing the technology for the treatment of waste paper such as the disintegration of waste paper pulp and softening and resolving foreign materials in applying our own kneading technology.
And, recently, we have succeeded in the development of totally new model of vertical separator washer, “Vertical Z (Zekoo)”.
  “Vertical Z (Zekoo)” has various unique functions in comparison with the conventional horizontal washing machine.
The pulp slurry to be washed theoretically moves from the lower side to the upper side, and the fiber and the impurities are separated efficiently through rotating cylindrical screen.
  Installation space required for “Vertical Z (Zekoo)” is 1/9 only compared with the conventional horizontal washing machine. In addition, the area of the required screen surface can be reduced to 1/3, the volume of consumed water can be reduced to 1/4 and electric power can be reduced to 1/4.
Brightness of the pulp can be improved after washing by “Vertical Z (Zekoo)” and, in addition, the improvement of the yield can be achieved.
  Furthermore, the screen of “Vertical Z (Zekoo)” has been used for approximately 9 years without replacement and the expenses for the maintenance can be minimized.
  We will keep developing the original and unique technology.

Continuous Pressure Gap Forming for Linerboard Production - Shoe-Blade Pilot Machine Results -

Yuki Hashimoto
Paper Machine Sales Department, Kobayashi Engineering Works, Ltd.
V. J. Wildfong, C. Holmqvist, J. A. Shands and J. A. Ronning
Johnson Foils, Inc.

Current trends of decreasing basis weights for containerboard has led to increasing machine speeds, motivating the use of gap formers. Application of Shoe-Blade gap forming technology for containerboard grades is discussed and pilot paper machine results are reported on. Formation, equal or better than current commercial gap forming, at low SCT ratios which approach fourdrinier forming were found.

Improved Yankee Protection and Product Quality through New Crepe Control Concepts

Masayuki Serizawa
Development Team, Maintech Paper Tech Co., Ltd.

  The demand of increased production and improved sheet quality tend to increase in recent years. But, simultaneously satisfy both requirements is difficult by using conventional creping control concepts. In particular, there are many cases will trade off sheet quality and productivity. For example, it is very difficult task to resolve once yankee protection and chatter prevention and sheet softness.
  Maintech has developed crepe control agents based on a new original concept, a solution that various problems about creping process.
  This report describes the concept and mechanism about YANKEEGUARDTM , DSL TM and SOFLEASE TM series, and introduces some interesting examples about chatter prevention and sheet quality improvement.

EVERLOY Spray Nozzles for Paper Mills

Takashi Nishiyama
Kyoritsu Gokin Co., Ltd.

  Kyoritsu Gokin Co., Ltd. which is one of the leading manufactures of spray nozzles was founded in 1938 in Japan. The company brand : Everloy is well known especially in Japan. The more paper machines are large and speed is fast, the more demands for spray nozzle is increase. With such continuous demands, spray nozzles became indispensable high precision parts nowadays. EVERLOY will introduce Straight Jet and Flat Fan pattern nozzles for paper mills.

Reduction of Paperboard Grammage Concerning Paper Strength Properties

Takushi Sakaemura
Research and Development Department, Paper Chemicals Division, Arakawa Chemical Industries, Ltd.

In packaging and papermaking industry, there is a tendency to reduce paperboard grammage from an environmental perspective. Paper strength properties generally tend to decrease as the basis weight is reduced. There is a need for reducing paperboard grammage and at the same time maintaining the strength properties. In order to solve this problem, it is essential to efficiently apply dry strength reagents such as acrylamide-based polymers and modified starches. We show the results of the experiments conducted in our laboratory;
1. Effects of basis weight of paper on the compressive and tensile strengths,
2. Efficiencies in strength improvement of dry strength reagents applied to paper by the internal and external application methods and by the combination of those methods,
3. Effectiveness of assistant reagents to retain fibers which have adsorbed the dry strength reagents.

The Design of Environment-Friendly High Performance Polymer

Kunihiko Kobayashi,Nobuhiro Matsuda and Takanori Yamashita
Performance Polymer Research Laboratories, JSR Corporation

  Recently, 3R (Reduce, Reuse, Recycle) has been promoted for resource saving. As a part of that, we have developed environment-friendly high performance polymer which can show enough strength of the coated layer with a small amount of polymer parts. In this paper, we will report about the design and the performance.
  In coated paper, functionalized styrene-butadiene polymer latex is used. It is required to form a continuous film and to bind pigment in the coated layer. However, reducing the polymer parts leads to a decrease in the number of polymer particle and polymers can’t form continuous films. As a result, we can’t get enough strength of the coated layer. So, we tried to minimize the size of the polymer particle because the number increases when minimizing the size. We investigated the influence of the size to the strength of the coated layer and the problem against producing a small size polymer particle. We confirmed that a small size polymer particle showed enough strength of the coated layer, but it was too unstable and the viscosity of its aqueous dispersion was too high to provide commercial scale. As a solution to these problems, we controlled the functional group distribution to the aqueous phase; decreased the amount of water soluble polymers and increased the bound functional group to polymer particle. In this way, we developed an environment-friendly high performance polymer which can reduce the polymer parts in the coated layer by more than 10% compared with those currently in use.

Full Automatic De-Wrapping of Paper Reels

Toshio Aoki
Maruishi Co., Ltd.

  Maruishi introduces a new technology of full automatic de-wrapping of paper reels by using special knife without damage the paper. In the beginning it was protected with timber and metal strap, today it is using the kraft liner and corrugated cardboard etc. for the wrapping style. For the converters and printers, it is necessary to reduce the load of operator and take away the wrapping in effective and safely.

The Behaviors of Inorganic Sulfur Compounds during Oxygen Bleaching

Iori Tomoda and Yosuke Uchida
Oji Paper Co., Ltd. Core Technology Laboratories
Emi Takakusagi
Oji Paper Co., Ltd. Functional Materials Laboratories

 Oxidized white liquor is commonly used as alkali in oxygen delignification. This is the reason that using the oxidized white liquor in this stage helps to maintain the sodium and sulfur balance in the pulp mill. The most regularly, sulfide in white liquor is oxidized to thiosulfate with air in an open reactor. In previous perception, thiosulfate does not change during oxygen delignification. However, some researchers found that thiosulfate was oxidized to sulfate during oxygen delignification recently.
 In the mill study, we found that thiosulfate was oxidized to sulfate during oxygen delignification. In the laboratory experiment, we confirmed that the existence of pulp was needed by oxidation of thiosulfate. Thiosulfate was oxidized by oxygen and this reaction was intermediated by lignin and pulp.
S2O32- + 2O2 + H2O → 2SO42- + 2H+

This oxidation scheme suggested that, thiosulfate oxidation consumed not only oxygen but also alkali. That is, the oxidation of thiosulfate which was derived from oxidizing white liquor consumed by the addition of 15% of oxygen and by the addition of 20% of alkali.