Vol.62 No.4 Abstracts

Mass Production of Eucalyptus globulus Elite Trees in Western Australia

Keiichi Shimizu
Forestry Science Research Laboratory, Nippon Paper Industries Co., Ltd.

  Nippon Paper Industries has developed the clonal propagation technology of E. globulus by tissue culture to supply a high yield, quality, survival rate and uniformity for plantation purposes. Selection of E. globulus tree, which were excellent in growth and tolerance to aridity, was performed in Western Australia. Trial mass production was done by using these elite trees and elite tree candidates.
  In tissue culture, red light by the Cold Cathode Fluorescent Lamp was used as a new light that changed into current fluorescent lamp. The rooting term and the growth term were shortened by using this.
  For the difference of growth by the quality of the soil and the planting density, trial plantations of clones were started in Western Australia.

Development of Reforest Technology Giving Environmental Stress Tolerance to Tree

Takayuki Asada
Forestry Research Institute, Oji Paper Co., Ltd.

  This theme aim at the development of the afforestation technology that reforest the region where the environmental stress is severe by the method of the environmental stress tolerance handily given to the tree according to fertilizing and/or chemical spray. Cytochrome P450 inhibitor such as Uniconazole-P gave the environmental stress tolerance to the eucalyptus. Uniconazole-P that showed the environmental stress tolerance giving action inhibited the metabolic speed of the abscisic acid which controls the environmental stress response. Uniconazole-P processed (0.025mg/plant) eucalyptus showed the stress tolerance, and the amount of initial (3.5 months) growth (dry weight) of plant under strong light environment increased to 1.5-2.3 times that of the control experiment. Uniconazole-P is a compound with high safety, which is registered as an agricultural chemical in Australia, and immediate effect for practical use would be expected.

Development of Energy-saving Flotator

Shintaro Sasada
Pulp Division, Tomakomai Mill, Oji Paper Co., Ltd.

  The rate of using waste paper exceeds 60% in 2003, and in order to raise it continually, we should expand the utilization of paper instead of board. Therefore, it is important to improve quality of deinked pulp and to save energy of deinking system. A flotator is one of the major deinking processes, which spends a lot of energy. In this presentation, the development of new flotator with reduced energy consumption is reported.
  One of the features of the conventional OK-flotator is its cell structure enabling high efficiency of deinking. On the basis of this cell structure, we focused on two important factors of deinking to reduce energy consumption; the contact of bubbles and pulp slurry, and the separation between bubbles and pulp slurry. The new flotator has structure which enables pulp slurry to contact with plenty of bubbles that are filled in a particular area, and stabilizes both upper region of slurry and froth layer. And it has three rooms to increase the contact and the separation. As a result, this new flotator realizes the 60% reduction of both the energy consumption and the volume, compared to the conventional OK-flotator.

Liner Machine Operational Experience of Octopus CP Control

Takaaki Abe
Kitakami Paper Co., Ltd.

  We introduced an Octopus System of Kobayashi Engineering Works, Ltd. as 1st. practical system in Japan for the purpose of improving the basis weight profile in cross direction and shortening the adjustment time required. All system is excellently running at present. We report the operational experience of this system since the start-up.

Combustion Improvement of Recovery Boiler

Kenji Nozaki
Ebetsu Mill, Oji Specialty Paper Co., Ltd.

  No.5 boiler of Oji Specialty Paper, Ebetsu Mill, Japan is a main recovery boiler in the mill, and was modified for Performance improvement since its construction of 1972.
For the reason of high cost of oil these years, further energy conservation becomes urgent top priority subject for us.
  We installed well proven Stacked Air System (SAS) of Anthony Ross (USA) to our No.5 Boiler in Oct. 2006 for combustion improvement and energy saving, which was the first trial in Japan.
  The result was to our full satisfaction in the various respect such as Economical merit, Increase of Through put, Reduction of Carry over Rate, Excess O2 Reduction, Improvement of Thermal Efficiency, Improvement of Steam production/Black liquor Ratio, Reduction of Air Heater Steam, Reduction of Soot Blower Steam Consumption, Improvement of Chemical Reduction Efficiency, Reduction of Burnable Gas, Less Emission/TRS and Prolonging of Run time.
  The installation work could be completed within the shut down time of 11days. We would like to introduce our experience about the combustion improvement work with SAS, including the economical effect and the outline of the modification of the system.

Operating Experience of Biomass Power Plant

Norikazu Baba
Kanto Mill (Katsuta), Hokuetsu Paper Mills, Ltd.

  Our Kanto Mill Katsuta division is located in the north in Ibaraki prefecture.
Number 1 power plant of the fuel oil use which is being operated since factory establishment up to now was doing energy supply by only one system. Introduction of new equipment was also urgent business as a production cost measure in addition to shake from production activities of CO2 reduction and fossil fuel dependence.
  Necessity in the energy plant where more correspondence to working old replacement of facility and the use energy with the factory production amount rise increase is tight and new than the factory establishment time has occurred.
  The form of "thermal recycling" for which a demolition wood is utilized as fuel as well as the "material recycling" which uses a recycled paper for a cardboard raw material from the past are complete by this biomass power plant, and the value as the resource circulation type factory is going to rise more.
  It's introduced about experience from introduction to commercial operation.

Energy Saving Case of Waste Water Treatment Facility

Eiichi Aisa
Fuji Mill, Oji Paperboard Co., Ltd.

  Nowadays, environmental destruction, especially the global warming caused by the increase of CO2 emissions, has been one of the biggest problems in the world, and to make proactive energy-saving efforts is the important issue for paper industry as a heavy energy-consumer.
  While active and effective measures has been taken for production line and power generating unit where large amount of energy is required, adequate measures has not been taken for effluent treatment facility.
  There were aeration route blowers for bio-treatment installed in the effluent treatment facility, however, route blowers had problems of high electric power consumption, noise, and vibration, and countermeasures to improve such circumstance were required urgently.
  I would like to introduce how we achieved to save electric power and to reduce environmental load by replacing the route blowers with K-TURBO's HIGH-EFFICIENT TURBO BLOWER.

Development of New Generation Newspaper, "PlusNews"

Hiroshi Shimase
Tomakomai Mill, Oji Paper Co., Ltd.

  New media such as Internet have significant impact upon Japanese newspaper industry these days. Newspaper publishing companies are trying to increase color pages in their newspaper to secure more customers who expect the greater effect in their advertisement. Oji paper has moved forward to R & D with a rapid improvement on color printing quality compared with standard newspaper.
  A couple of novel technologies, such as "Super White Carbon" and "Fine Plus Coat" have successfully developed. White Carbon (Hydrous Silicic Acid) is an effective filler which prevents print through. "Super White carbon", manufactured in controlled conditions, has superior performance to the conventional one with less addition ratio. "Fine Plus Coat" remains ink on the surface of the paper and is able to obtain greater printing quality compared with standard newspaper.
  New generation newspaper "PlusNews" consists of these two key technologies to achieve extreme printing quality and was brought to market officially last fall. Half of the production of Oji's newspaper has already been replaced from conventional newspaper to "PlusNews" as of June 2007, and replacement would be completed by the end of this year.

Development of Lightweight Coated Paper for On-demand Printing

Hisahiro Omote
Nippon Paper Industries Co., Ltd.

  The market of on-demand printing in printing industry is expanding these several years. In recent years, with high speed on-demand printing machine of electrophotography that utilizes flat sheet, the opportunity to print on coated paper is increasing. Furthermore, the requirement for lighter coated paper is getting stronger.
  However, coated paper, especially light coated paper with low stiffness, led problem of poor runnability because coated paper was easy to stick to toner transferring part and toner fixing part within printing machine compared with wood-free paper.
  In order to solve this problem, light weight coated paper for on-demand printing was developed by mixing a new stiffness improving reagent (Polyacrylamide) with good coating aptitude to coating color. This light weight paper for on-demand printing combines the good on-demand printability (printing quality, runnability) with the excellent offset printability, and is also designed to provide the easy-of-use by operator.

Development of Hydrothermal Reaction Solidification of Paper Sludge Ash

Hirotoshi Takeya, Toshiyuki Nago and Masahiro Sasaki
Kushiro Mill, Nippon Paper Industries Co., Ltd.

  Paper sludge is mainly the waste of de-ink pulping plant and is burned in sludge boiler to recover energy and to reduce its volume. Sludge boiler ash is utilized as the raw material to produce cement, but the amount of sludge boiler ash increases due to the increase in the capacity of de-ink pulping plant. Therefore it becomes more and more important to develop other processes using sludge boiler ash as raw material.
  Recently, we have developed a harmless product by hydrothermal reaction solidification of boiler ash and have been making an effort to enlarge the usage of this new product.

A Report on 2007 TAPPI Engineering, Pulping & Environmental Conference (2007 EPE Conference)

Iori Tomoda*1, Shinichi Onogi*2 and Hiroshi Araki*3
*1Oji Paper Co., Ltd.
*2Nippon Paper Industries Co., Ltd.
*3Japan Pulp and Paper Research Institute, Inc.

  The 2007 Tappi EPE Conference was held on October 21-24, 2007 in Jacksonville, FL, USA. The 435 people from 17 countries including Japan, Sweden, Finland, Brazil, China, Canada and USA, participated in the conference. The 101 papers including two Japanese papers were presented in 51 sessions. The topics of engineering, puling and environmental divisions of the conference were reviewed in this report.

Effects of Cooking Conditions on the Bleachability of Bamboo Kraft Pulp

M. Sarwar Jahan, D. A. Nasima Chowdhury and M. Khalidul Islam
Pulp and Paper Research Division, BCSIR Laboratories

  The bleachability of kraft pulp from wood has been the subject of several reports, but little effort has been made to assess the bleachability of nonwood pulp. This study evaluated the cooking conditions, such as active alkali charge, cooking time and sulphidity on the bleachability of bamboo kraft pulp. We cooked bamboo chips to kappa number around 20 by alternating cooking variables. We then quantified pulp yield, and evaluated pulp quality through measuring unbleached brightness, viscosity, pentosan, -cellulose and phenolic hydroxyl group (PhOH) content in the residual lignin of pulp. Pulp produced at higher active alkali charge and sulphidity had higher pulp yield, higher -cellulose, viscosity and lower pentosan in pulp and higher PhOH content in the residual lignin. After oxygen delignifying the pulp, bleaching was done by DED or QPP sequence. Degree of oxygen delignification had no relationship with the cooking conditions. The bleachability of pulps was determined by measuring consumption of chlorine dioxide to attain 80 % brightness level. The bleachability of pulp was improved when pulping was done in higher active alkali charge and sulphidity. The bleachability of bamboo kraft pulp showed a direct relationship with PhOH content in the residual lignin.

Keywords: Bamboo pulp, active alkali, Suphidity, Bleachability, Brightness, Phenolic hydroxyl group

Development of Manufacturing Process for High Quality Calcium Carbonate by Causticizing Process in a Kraft Pulp Mill (Part4)
- Investigation of Continuous Reaction for Rice-like Particles -

Yasunori Nanri, Haruo Konno and Hideyuki Goto
Pulp and Paper Research Laboratory, Nippon Paper Industries Co., Ltd.
Yasuhiro Okamoto
Ishinomaki Mill, Nippon Paper Industries Co., Ltd.
Kazuto Takahashi
Gotsu Mill, Nippon Paper Chemicals Co., Ltd.

  Precipitated calcium carbonate is produced as a by-product in the causticizing process of the kraft pulping process. There are many advantages to use this by-product, causticizing calcium carbonate (CCC), as filler and coating pigment in paper. By using this CCC for paper materials, lime-kiln operation would be reduced or eliminated, resulting in the reduction of fuel oil for calcination of calcium carbonate. Furthermore, accumulated impurities in the lime cycle can be removed constantly. In our previous reports, we showed that CCC particles with a various kind of morphology were obtained by separating and precisely controlling the two reactions of slaking and causticizing in the causticizing process. Among these morphologies, rice-like particles can be produced with the least process modification. Thus, the production trial of rice-like particles at mill scale was done and then the industrial production of the rice-like CCC was succeeded. However, this production process was based on the batch reaction. Continuous reaction is preferable compared to batch reaction in industrial process. Therefore, in this report the production trial of rice-like particle by continuous reaction at laboratory and mill scale plant are carried out. We found that rice-like particle with low wire abrasion ratio can be produced at mill scale plant by controlling the residence time of slaked lime slurry and green liquor at first causticizing tank. Moreover, filtration properties of CCC are also improved by the additional feeding of slaked lime slurry and green liquor to #3 tank.

Keywords: Causticizing reaction, calcium carbonate, continuous reaction, mill trial