[in Japanese]

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The“Gran Flow”is a pressure screen which was awarded Sasaki Prize by Japan Tappi on2000, because of its dramatic power saving and much superior sticky removal comparing with conventional screens.The major technology of the Gran Flow consists of three key components, which are two stock inlet construction. efficient hydrofoil and New Wave Screen Basket.
The Stock-Contamination-Analyzer is a newly developed facility to detect contaminants contained in stock on line, which will be used for quality control of various stocks.

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An on-line sensor system for measuring fiber orientation of paper was newly developed.The sensor has a special optical configuration to measure light reflected from the surface of paper running at high speed.The sensor is composed of unpolarized light source that illuminates paper surface perpendicularly, several photo detectors and polarizers attached to the detectors.The detectors are distributed on the circumference of a circle defined in a plane being parallel with the paper surface.
The intensity of the light reflected from paper surface is measuredsubstantially in the same instant by the detectors.Fiber orientation is determined by the angular dependence of the light intensity.
The anisotropy is a direct result of the light reflection from the lateral surfaces of the fibers.
Two sensors, which were prepared for measuring both felt and wire sides of paper, were installed between the calender roll and the reel of a paper machine in Komatsushima Mill.We succeeded in measuring fiber orientation profiles in the cross machine directionand the machine direction. These sensors had been used to control quality for curling of copy paper in Komatsushima Mill for five years.
The technology was licensed to Yokogawa Electric Corporation.Two pairs of sensors, which were incorporated into the B/M 7000 XL, have been used in Komatsushima Mill since July 1997.Three pairs of manufactured goods have been applied in two of our mills up to now.

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To cope with the globalization and diversification of the environmental issues, Hachinohe Mill has operated the environmental management system (EMS) conformable to ISO14001since April1998, and then was allowed to be the first Japanese integrated mill of pulp and paper that gained the certification of ISO 14001.
The preparation for the requirement specified in the International Standard was set up, Hachinohe Mill was inspected by Japan Management Association in October1998and certified on ISO14001in November1998.
The EMS has been running smoothly since it was started.However some parts of the EMS should be improved.Making the EMS streamlined and easy to use is the major undertaking in the near future.

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Nippon Paper Industries has been developing the next generation technology using the biotechnological technique in order to establish the competitive wood chip supply system for the 21st century. Plantation of cloned elite trees, one of the advanced plantation technology, reveals that it enables to reduce the chip costs significantly and to gain high pulp yield.However, providing mass elite clonal plantlets in the limited plantation with meeting the commercial plantation costs was not easily accomplished. Therefore.development of new technologies has been desired.In this paper, using the case of Eucalyputs globulus.we have mainly studied to date, the mass tree production technology by tissue culture, the rooting technique by photoautrophic culture, and low-temperature plant tissue storage method that is currently developed are reported.

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It is well known that moisture barrier laminated paper sheets having a layer made from polyethylene can prevent permeation of moisture. But the conventional moisture barrier laminated paper is disadvantageous in that, after use, the paper sheets cannot be satisfactorily repulped and recycled.
On the other hand, paper sheets having a layer made from wax and waterborne synthetic resin have moisture resistant and repulpability.But wax has problems to bleed out to the surface and transfer the contents or backside of sheets.
We have developed a new recyclable moisture barrier paper that consists of a styrene-butadiene rubber (SBR) latex filled with plate-like fillers. The degree of the moisture barrier is equal to that of a polyethylene laminated paper.We have studied the Theory of the water vapor permeation which is to be explained by Maxwell tortuous effect.It has turned out that the permeability is significantly affected by the interface between the latex and fillers.It has been also found that plate-like fillers depress the solubility of the latex film.

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A new regulation standard was enforced on April1, 2000 for dust emission from incinerators.The mill had to reduce its dust content in the discharge of its sludge incinerator from0.5g/m³N to 0.08g/m³N. We studied various dust removers and found that a ceramic filter would be a best choice.
A ceramic filter is expensive compared to bug filters that are commonly used in the industry. It, however, has a longer life and needs less space with the same level of removal efficiency of bug filters.

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Honsha Mill Fuji of Daishowa Paper Manufacturing Co.Ltd.is trying for the establishment of recycle mill making good use of geographical conditions located near the Tokyo etropolitan area. Corresponding to the demand increase for recycled paper, we planned to operate new DIP plant this year and keeping up with the increase of paper sludge (PS) and energy consumption in the facility. we planned a new incineration and power generating plant using waste as auxiliary fuel and completed the plant in April.
As the auxiliary fuel we selected Cut Tires with high calorific value and stable quality.
The boiler generates max.65 t/h steam and the extraction and condensing turbine generator generates 14, 500 kW power.The PS dewatering equipments are replaced by screw presses entirely.
This report describes the outline and operating experiences of a new incinerator and power generating plant.

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Hokuetsu Niigata Mill started up the new coated paper machine (PM8) and the new pulping plant in1998.
Before operating those plants, new waste water treatment with high-purity oxygen activated sludge system started.This system needed smaller set up area than conventional, its an advantage of this system.We expect a efficiency biological deodorization of kraft waste water.
Now we report the operating experiences and some troubles of this system for three years.

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We installed the high performance anaerobic waste-water treatment system instead of our conventional plant.The Internal Circulating Upflow Anaerobic Sludge Blanket (IC-UASB) was chosen for its good performance of cost-saving, easy operation and the small amount of a surplus sludge.
The anaerobic system convert the organic acid coming from foul condensate, white-water and the fermented residue into the biogas.In the future, we believe that the aerobic and the anaerobic waste water treatment system be combined.They be more effective for pulp and paper mill for its good performance.

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Fuzzy Control System was introduced at Kishu mill for the purpose of improvements or fulfillments such as, getting stable operation, uniformity of the operation bet-ween each shifts, stabilization of the product quality, energy saving as well as level up of the operating technology and reduction of work load for the operators.
Fuzzy Control System was installed and commissioned in October, 1999 and tuning and optimization for it had been done until June, 2000.The performance test was carried out from the end of May to the beginning of June, 2000.due to a rather limited period for such the test, as to the stabilization of the product quality as well as energy saving, significant improvements could not be observed so far, however operator's work load could be observed to have reduced significantly, since operators had almost nothing to do than just to supervise and monitor the operation controlled by it during a period from the beginning of June to the end of July until a start of annual shut down, while the plant had been operated with full control by Fuzzy.
Fuzzy Control System was delivered by FLS Automation A/S in Denmark through Kvaerner Pulping KK and the main characteristic of this system is summarized that the intelligent control system that behaves in the way an experienced operator would do, the graphical operator's interface, and the change or addition of software being easily done by user themselves.
After further fine-tuning with this system, we firmly believe that Fuzzy Control System will be regarded to be indispensable for the operation of Recausticizing and Lime Kiln in our mill.

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A new process has been developed to produce high quality calcium carbonate as a paper filler using causticization step in kraft pulping process.This causticization calcium carbonate (CCC) is by-produced during the step for converting green liquor to white liquor.If CCC could be extracted from the step as a paper making material, the lime-kiln operation can be shortened or could even be stopped depending on the amount of CCC extracted, thus saving the cost of fuel oil and reducing the discharge of carbon dioxide gas.However, the conventional CCC was massive and included non-uniform particles with large diameters, demonstrating severe plastic wire abrasion and poor paper opacity.
Then, we challenged to control the shape of the CCC.Green liquor is mixed with a quick lime to produce CCC by two-step reactions: slaking of quick lime with water and causticizing of the slaked lime with sodium carbonate.These reactions were fundamentally separated and carefully controlled, and then it was found that various shapes of CCC in the form of rice-, spindle-and needle-like particles can be obtained.demonstrating good opacity and wire abrasion resistance as a paper filler.Especially, the needle-like CCC of aragonite crystal demonstrated comparably higher opacity than commercial aragonite CC. Findings from the laboratory reactor were used to successfully scale up to mill scale plant. A new mill plant for manufacturing the needle-like CCC has been ready for operation in Iwakuni mill of Nippon Paper.

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[in Japanese]

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Xylanase treatment with on-site enzyme production was introduced into the hardwood kraft pulp bleaching process (C-E/O-dnD) at Yonago mill in October, 1998.A thermostable xylanase from a microorganism, Bacillus sp.S-2113, that we isolated through screening was selected for use in this process.The xylanase-containing culture was applied to the bleaching process without removing the bacterial cells from the culture medium.Two years have passed since the xylanase treatment operation, with onsite enzyme production, was begun, and so far, this operation has been working well.
The ECF bleaching sequence will start operation within the year 2000in Yonago mill.The effects of enzyme bleaching in the ECF bleaching process are expected to be even greater then.

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