2005年7月 紙パ技協誌

[プリント用ページ]

Current Situation on Recovery and Utilization of Recovered Paper in Japan

Haruo Takayanagi
Paper Recycling Promotion Center

 The collection and the utilization of the recovered paper in Japan, has expanded rapidly for these several years owing to the supply and demand of recovered paper both industry’s effort.
 It was achieved the target in the fiscal year 2003, as to the target of the utilization rate of the recovered paper moving up 60% by the fiscal year 2005.
 Especially, the amount of the recovered paper usage has been exceeded more than amount of the recovered paper collection as of 2000, and so the amount of recovered paper export to foreign countries has been increased.
 On the other hand, we have many problems on the balance of recovered paper supply and demand in Japan, and on the instability of recovered paper prices according to expansion of recovered paper collection amount and increasing of recovered paper export. Additionally, there are problems like the recovered paper availability target after the fiscal year 2005 and the recovered paper quality control in the collection process.
 It introduced the current state about these points, and described the way of the paper recycling improvement in the future with this report.


A Report on Investigation on Recyclability of the Troublesome Paper Materials in Paper Recycling Process

Atsushi Watanabe
Research Development Div., Pulp and Research Laboratory, Oji paper Co., Ltd.
Mitsuhiro Sugino
Production Dept. Technical and Engineering Div., Nippon Paper Industries, Co., Ltd.

 The Japan Federation of Printing Industry (JFPI) has been starting the project to support the development of recyclable paper-based products since 2002. The main activity of the project is to investigate the recyclability of the paper materials which were thought to be difficult to recycle such as “gold, silver, pearl, UV ink printed paper, varnished paper, and plastic laminated.” The lab experiment was completed in 2002 and the pilot plant trial was done in 2003. Base on the results, JFPI suggested the probability for the real usage of the materials in the industry.
 This paper reported the results of the recyclability evaluation on ten paper-based materials. The samples were following; offset gold, silver, pearl ink printed, UV ink printed, gravure gold ink printed, gold-gilt paper, two types of hybrid UV ink printed, UV varnished, and PP laminated paper. Offset gold, silver, pearl printed and hybrid UV ink printed turned to be appropriate for recycling. On the other hand, rest of the paper materials was not suitable for recycling due to rough and large ink particle or fragmented film remained in the recycled pulp.
 The next step is to propagate the recyclable materials. Then following step shall be needed; 1) reflecting the results to the standards of the industry, 2) preparing signs or indications for recyclable paper materials, 3) public support for the recycling facilities, 4) public education on recycling.


ModuScreen™ A - the Modular Screening Principle

Jukka Rinne
Andritz OY
Mirka Sireni
Andritz AG,
Yosuke Takeshita
Andritz KK

 The new ModuScreen™ A presents a completely new screening family that has been developed for the pulp and paper industry. It is based on experience from more than 2000 plants supplied worldwide since 1950.
 Many new ideas were used in developing the new Andritz ModuScreen™ A pressure screen series. Special attention was given to the hydraulic requirements of the housing in combination with the rotor to achieve optimum flow conditions for highest screening efficiency and reliability.
 The ModuScreen™ A pressure screen series was designed to have exactly the right combination of screen cylinder (slot width and profile, cylinder diameter/height ratio) and rotor (foil or solid type) for each process, from DIP fine screening to kraft pulp screening. Since it is so flexible we are able to achieve cost-effective solutions combined with highest screening efficiency.


The Introduction of Latest Technologies for Contaminants Separation at Loop 1 Stage in Advanced Deinking System

Masakazu Eguchi
Application Engineering Dept.,
Voith IHI Paper Technology Co., Ltd.

 Pulping, Screening at Loop 1 stage are very important technologies for removing contaminants in Deinking system. Effective and economical stock preparation system always require to develop new system, new equipment and innovative technology in order to get high cleanliness, minimal fiber losses and investment costs.
 This presentation picks up some of the latest technologies of sticky contaminants removal for DIP processes, particularly Pulping and Screening at Loop 1 stage based on actual references in Japan, Europe and other countries.


How is the Latest Technologies for Sticky Removal of DIP

Takeshi Kanazawa
Aikawa Iron Works Co., Ltd.

 One of the most important subjects for DIP is now how to handle the sticky problems. For optimum sticky removal, it is required to combine various “Separation Technologies” appropriately, such as Pulping, Screening, Cleaning, Dispersing, Floatation and Wet-End approaching.
 This paper introduces the latest developed equipment, especially, new screening machine and dispersing equipment, relating to sticky removal.


Deinking Agent for Used Paper Printed with UV Curable Ink

Makoto Wakatsuki
Chiba Research Laboratory, Toho Chemical Industry Co., Ltd.

 The paper manufacturing industry in Japan is trying hard to reach its goal to raise the percentage of waste paper recycling to 60% by 2005. To achieve this target, relatively low grade waste paper must be used, while at the same time, the quality of de-inked pulp must be improved. For significantly increasing the use of lower grade waste paper, maintaining regenerated pulp quality, removing foreign materials and selection of waste paper must be conducted.
 In recent years, printed materials with UV curable ink are often included in waste paper. The ink in the paper printed with UV curable ink is difficult to remove in the deinking process. As the amount of the waste paper in the printed materials increases, the quality of the DIP decreases dramatically. However, there is no feasible method to measure the exact mixing amount of the UV curable ink printed materials. Therefore, we have developed a deinking agent with a new function.  This new function has exceptional ability to remove UV curable ink.
 This is to report a de-inking agent that can produce high quality deinked pulp.


De-inking Agent and Assist Agent for Recycling Paper

Takashi Tanaka
Paper & Pulp Group, Specialty Chemical Department,
Research & Department Division, NICCA CHEMICAL Co., Ltd.

 We have been used recycling magazines with lack of wastepaper. Then less refining and developing flocculation pitch occurred from special coating component or paste resin. Until recently, high molecular form-nonionic activator was used for de-inking agent. However, a single element composition is not enough activator to penetrate and disperse. To make hybrid the action of the activator provides excellent de-inking performance that does not make above problems.
 Also, using polycyclic oligomerform form-anionic activator shows effect of prevention of re-adhesion and depression of flocculation of pitch. These composition moderates having influence to function of activator, like families, permeability, and adsorption.
 Generally, in the process of hydrogen peroxide bleaching, sodium silicate is used for peroxide stabilizer. However, it is piling which soils in the system and clogs the pipe. Using non-silicate-poly alpha hydroxycarboxylic acid alkali salt improves bleaching effect and makes recycling paper grater whiteness.


The Technology to Make a High Quality DIP

Yasushi Ikeda
Kao Corporation, Performance Chemicals Research Laboratories

 Although the waste paper has been recycled for a long time, further recycling of the waste paper is recently expected in terms of environmental preservation and resource conservation. Old newspaper (ONP) has been mainly used as a furnish for various recycled papers, but it comes to the limit on amount of side. Therefore it is desired to utilize the lower grade waste paper (LWP) for recycled papers. Since LWP is cheaper than ONP, utilizing LWP is economical. Moreover, using LWP as a furnish contributes to the resource conservation greatly. However, there are some problems which should be solved when LWP is recycled. In this paper, the approach to solve these problems is reported as an example of old magazine waste paper (OMG) which is one of LWPs.
 Needless to say, the deinking is important and additionally the sticky removal is also required for OMG’s recycling. At first, the mechanism of the sticky generation is examined and the concept of sticky removal is proposed. Sticky is classified into the macro sticky and the micro one by its behavior. In the actual operation, it was found that the sticky troubles were often originated from the macro sticky which the micro sticky became by coagulation.
 Therefore, it is very important to remove the micro sticky. The deinking process was thought to be more effective to remove sticky, compared to the papermaking process. Concretely, the flotation process which was one of the ink removal process in the deinking was selected. To attach effectively the sticky on air bubble surface was the key point of this technology. By changing the characteristics of the sticky surface based on the surface science, the sticky-sticky coagulation was promoted and the sticky-bubble affinity was increased. The possibility to remove the sticky was established.


Substances of the Environment-conscious Sheet-fed Ink and Standard for Offset Printing Services

Tadashi Nakano
Toyo Ink MFG. Co., Ltd., Printing & Information Business HQ, R&D Division

 Over the last decade, environmental issues in Japanese printing industries have been changed strictly. Many companies are interested in “environment-conscious products” for their own printed matters. Three standards of offset printing are popular as follows,
1: The Japan Federation of Printing Industries” “Green Standard for Offset Printing Services”
2: Japan environment Association “The Eco Mark Program”
3: Green Purchasing Network “Purchasing Guides line for Offset Printing Services”
These Standards show main five rules,
A: not use substances harmful to human body
B: not use chloride resin
C: considers substances specified by PRTR law
D: controls VOC emissions
E: considers reducing factors that prevent recycling used papers
Ink manufacturers have been developing new environment-conscious products on condition that choosing substances according to these rules.


The Experiences of Dirt Removal from Deinked Pulp

Hiroshi Yamashita
Hachinohe Mill, Mitsubishi Paper Mills Limited

 While the utilization rate of waste paper has been increasing in Japan, the amount of the product arranged the deinked pulp has also been increasing recently at Hachinohe Mill. This makes the deinked pulp more important to us. On the other hand, the techniques of dirt removal, especially sticky particle removal, from the pulp have become very important because increasing the amount of product of the deinked pulp sometimes not only caused the quality problem but also prevented making the deinked pulp.
 It is very important to prevent stickies from being subdivided when we remove them from the pricess . We modified the conditions of the defibrating process in order to slow down or prevent stickies from being subdivided. After several trials, finally, stickies were effectively removed in the screen stage. Despite the improvement of sticky particle removal, some very tiny particles of sticky still remained in the end product of the deinked pulp.
 We re-arranged the operating conditions of the disperser in order to make sticky particles even smaller so that they could be removed during the washing process. We finally arrived at the better technique of sticky particle removal from the pulping process and we were able to create a more stable quality of the deinked pulp.

Keywords: deinked pulp, dirt, sticky, removal, modify, subdivide, disperser


Dirt Control in DIP Process
−Recent Trend of Dirt and On-line Dirt Measurements−

Yukitsugu Kado
Ishinomaki Mill, Nippon Paper Industries

 In DIP process, the troubles of dirt such as stickies and residual inks are currently increasing at rapidly pace because of downgrading of recycled paper and improvement of printing technique. Technical advance of screen and dispersion system is able to achieve more selective removal of dirt; however, it is hard to solve the issue of dirt completely. We need knowledge of dirt and instrument to control it so that we are annoyed with dirt troubles.
 On-line dirt counter enables constant surveillance of dirt and prompt attention without lag lime by measuring it directly in the pulp slurry on the process. We are taking full advantage of dirt management since we had phased in it to three DIP processes.
 In this paper we present recent trends of dirt and examples of dirt measurements by using on-line dirt counter.

Keywords: DIP, dirt, dirt counter, inks, stickies


The Improvement of Efficiency in the Screening in DIP Lines

Hideyuki Nomura
Kanto Mill, Hokuetsu Paper Mills, Ltd.

 Since 1975, the Kanto Mill (Katsuta) has produced white board using largely DIP. DIP lines also have been operated since the beginning of the mill, and they were remodeled the facilities several times in order to improve the quality of products, enhance the treatment of various stocks and increase the output.
 Now, two DIP lines are operated, changing sorts of recovered paper and treated volume, depending on the type of the products. These days, because of the deterioration of quality of recovered paper and customers’ demands for low dirt, the main issue is to improve the efficiency of cleaning in the process, which we attempted to achieve in the regular operation. However, the capacity of screening for old magazine was so limited that the DIP lines were renewed the coarse screens in 2003 and replaced the pre-dewaterers and fine screens in 2004. As a result, we could achieve reduction in dirt in the products.
 This report shows an overview of the facilities, the operation and quality improvement by remodeling.


Mill Experience of the Improvement of DIP Quality

Kenji Nagata
Chuetsu Pulp and Paper Co., Ltd., Futatsuka Mill

 The use of recycled paper has been promoted in Japan, as the campaign of recycling rises and the measures of cost reduction is implemented in the background of prevention from Global Warming and conservation of the Natural Resources. Recently, the inclination to such motion has been affecting the supply-demand balance of waste paper, and then the contamination level has changed for the worse.
 In Futatsuka Mill we also have raised the combination rate of DIP every year. But under the above-mentioned situation, the sticky trouble has caused the deterioration of the paper machine operating rate, and although this is a rarely case, pin-hole due to adhesive object was found at the rotary newspaper press of customer. In order to solve these problems, while reexamining the revaluation level of dirt spec, we have been tackling the measures of reduction of DIP dirt spec with strengthening coarse screen, fine screen and cleaning of light contaminations on the DIP manufacturing process.


Flotation for Printing and Writing Paper

Yasuto Tanaka
Technology Division, Oji Paper Co., Ltd.

 The utilization rate of waste paper reached 60.2% in 2003. The expansion of utilization for paper instead of board will be necessary to promote above figure (60.2%). This will require an improvement of DIP quality close to virgin pulp without extra cost possible.
 In this article, OK Flotator is introduced for high quality as an example of efficient rotary mixing system. This Flotator can be operated over a wide range of G/L and atomizer rotation speed to have stable de-inking effect on every ink sizes depending on material and operation.

Keywords:ONP, de-inking, flotation, Flotator


Analyses of Mucilaginous Compounds Used in Making Traditional Handmade Paper

Yoon-Hee Han, Masahiro Yanagisawa, Toshiharu Enomae and Akira Isogai
Graduate School of Agricultural and Life Science, The University of Tokyo
Tadashi Ishii
Forestry and Forest Products Research Institute

 In the case of making Japanese and Korean traditional handmade paper, mucilaginous compounds extracted from roots of Abelmoschus manihot (Tororo-aoi), Hydrangae paniculata (Noriutsugi) and others with water are added to bast fiber suspensions to improve dispersity of the fibers. Although many studies in terms of chemical structures of mucilaginous compounds and their properties in aqueous solutions have been reported, there are still many unclear research subjects.
 In this study, three mucilaginous compounds extracted from roots of Japanese and Korean Abelmoschus manihot (JAM and KAM, respectively) and Japanese Hydrangae paniculata (JHP) are subjected to several chemical analyses to distinguish these compounds. Neutral sugar and uronic acid composition analysis clearly gave different results among the three mucilage samples. The major metal elements were sodium and calcium for the JAM and JHP samples, while that was potassium for the KAM sample. The three mucilage samples were distinguishable by their pyrolysis-GC patterns obtained by the on-line methylation method. Size exclusion chromatographic analysis attached with a multi-angle laser light scattering detector (SEC-MALS) of the mucilage solutions in 0.1M NaCl revealed some differences in molecular mass values and conformations in the solutions among the polysaccharide components in the three mucilage samples. The JAM and KAM samples had similar weight average molecular mass values around 2300000-2500000, and the JAM and JHP samples had similar random-coil molecular conformations. However, it is unknown at this moment whether or not the obtained differences are applicable to all Japanese and Korean mucilaginous compounds extracted from plant roots of the same species.

Keywords: mucilage, tororo-aoi, SEC-MALS, FT-IR, sugar composition, pyrolysis-GC