In 1994, a project team has submitted to the board of directors “The Guideline for the 21 st Century : the report entitled aiming at training of the engineer who bears the next generation, and higher technology”. Then, it has worked according to the recognized report. The proposal was again looked over by leading the Junior Steering Committee in 1998. As a result “The Guideline for the 21 st Century : aiming at the further development” was submitted anew. Henceforth, activity has been promoted that this proposal should be materialized. Since five years were passed after that, while the Junior Steering Committee takes the lead and summarizes activity in the meantime again, in order to strengthen the base of JATAN TAPPI, the report about a new action policy was submitted to the board of directors in June, 2004, and it was recognized.

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Operating treatment systems for the pulp and paper industry can be quite challenging considering that treatment regulations are getting more stringent and mills are changing their operations. The mill operation changes have changed wastewater characteristics and the loadings to previously successful operating plants. The result is that some existing treatment plants cannot consistently meet their effluent discharge permit.
Success or failure in activated sludge systems depends on growing a biology that has good settling characteristics that will produce a quality final effluent from the secondary clarifier. There are many problems that can occur in activated sludge systems such as poor settling and foaming. This paper discusses these problems by listing possible symptoms for each problem, the potential causes and the methods available to correct or control the problem.

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The extraordinarily large amount of the industrial water is used in the pulp and paper industry among major domestic industries. It is discharged through the process in the secondary treatment such as bio-treatment process. Therefore, the wastewater treatment at the bio-treatment processing in the pulp and paper industry is an important theme. Although bio-treatment processing is a popular method, many factories are facing problems at wastewater treatment with several factors, such as increase of load and process fluctuations. Moreover, since it is assumed that the regulation for effluent standard becomes stricter due to consideration of environment issues, the demands for the improvement on capability and stable operation for bio-treatment processing are increasing year-by-year.
In these circumstances, we have been applying products by the name of “MC Series” for Bioaugmentation. The Bioaugmentation is the practice to add bacterial preparations which have high growth capability into the current bio-treatment process. The bacterial preparations in MC Series have specific catabolic abilities which can degrade certain components in the wastewater. Bioaugmentation can enhance the performance of an indigenous biomass to respond against process fluctuation.
In this article, it introduces the feature of MC Series, the results of field tests and “MC+Chlorination processing” which is a new method of filamentous bulking treatment. These results indicate that the MC Series lineup meets the various requirements for industrial wastewater treatment at pulp and paper industry. It is considered that it can contribute to the pulp and paper industry on the reduction for environmental impact.

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BODs biosensor, BF-2000, with immobilized microorganisms was developed for measuring the biochemical oxygen demand in industrial wastewater. BF-2000 is able to use even microorganisms in active sludge other than Trichosporon sp.
Also BF-2000 is adopting antiseptic tubing to prevent blockage by microbial contamination. BF-2000 is able to equip wastewater sampling⁄dilution system and data transmission systems to improve the performance. The result that measured various kind of wastewater by using the BODs biosensor is shown.

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For oil fired boiler plant, SO₃ gas is cooled down forming very fine mists through wet type flue gas desulfurization system (wet-FGD) . Therefore, removal of SO₃mists is very poor at FGD absorber, which causes a long visible smoke from the stack. To overcome this problem, installation of wet type electro static precipitator (wet-ESP) is the most suitable, however this system is not widely used due to the space limitation or expense.
An advanced gas cleaning system has been developed, which incorporates the function of wet-ESP into wet-FGD. This paper introduces the principle of the new technology, along with the operational experience at the commercial scale plant. This system is called Mitsubishi Di-electric Droplet Scrubber (MDDS) .

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Waste water from paper mill is much quantity, but it is comparatively clean without SS. Requirement for environment management increases recently, and regulation about waste water becomes severe. On the other hand, the quality of waste water from paper mill have taken a turn for the worse due to request of paper recycle. And now paper mill become to have new waste water treatment in order to prevent water pollution. We have developed for 8 years a simple waste water processing, that have Transporting Bed I called (Ryu Ryu Bio System) . I will show the history and feature of Ryu Ryu Bio System.

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The moving bed biofilm reactor using sponge media has characteristics such as that can be operated with high load BOD and easy maintenance. Pilot plant tests using this reactor were conducted for paper mill wastewater treatment. And so the performance of full scale moving bed biofilm reactor using sponge media was investigated, modifying an existing paper mill wastewater treatment plant.
In the pilot plant test, S-COD was removed over 65% at COD volumetric loadings below 4kg⁄ (m³•d) , and S-BOD was removed over 90% at BOD volumetric loadings below 3. 5kg⁄ (m³•d) . The moving bed biofilm reactor using sponge media showed high performance of organic removal. Furthermore this pilot plant effluent COD was removed about 80% by chemical precipitation test, conducted with the addition of 200mg⁄L as Al₂ (SO₄) ₃•18H₂O and 1mg⁄L as anion polymer at pH6. These results show that soluble and particle organics is removed effectively by combined process of moving bed biofilm reactor and chemical precipitation.
In the full scale moving bed biofilm reactor, S-COD was removed over 70% at S-COD volumetric loadings below 2kg⁄ (m³•d) , about 60% at S-COD volumetric loadings of around 3kg⁄ (m³•d) , and S-BOD was removed over 90% at S-COD volumetric loadings below 2. 5kg⁄ (m³•d) . Performance of full scale plant was higher than designed value with 60% S-COD removal at S-COD volumetric loadings below 2. 5kg⁄ (m³•d)
These results show that high organic load treatment is achieved with the moving bed biofilm reactor using sponge media for paper mill wastewater, and this reactor is effective for improvement of existing plant.

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The wastewater treatment system applied to the pulp and paper factory is required to save space and to save cost of construction and operation. In this paper 3 systems which suits the requirement are introduced.
1) Biobed® EGSB system is a high load anaerobic wastewater treatment technology using the granular biomass. This technology has merits-high organic loading capacity, low power consumption, less sludge discharge, energy recovery from bio-gas.
2) Sumi-Sludge system is a space saving wastewater treatment system. Sumi-thickener-High rate coagulation and sedimentation system-is combined to activated sludge treatment process.
3) The membrane bio reactor (MBR) system applies submerged membrane units inside of the aeration tank of activated treatment process. The permeated water quality is very clear. This system is a high space saving wastewater treatment technology.

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UNOX system has been used in various fields as its unique treatment process for years, and the number of installations reaches over 150 plants in sewage and industrial waste treatment in which more than 40 plants are for pulp and paper waste.
This process was developed in a leading chemical company in USA. In Japan, Showa Engineering, which took over Showa UNOX K. K, has been marketing since introduction of UNOX technology, and has continously advanced UNOX system with lots of experiences ; especially for cost-reduction of both construction and operation as well as for optimum design conditions.
Since UNOX system uses high purity oxygen gas as aeration gas instead of air, there are many advantages compared to a conventional treatment process. Thanks to customer's highly evaluation for UNOX system, the large size treatment plants in pulp and paper waste have been mostly UNOX system. Besides, the expansion to the existing plant are similarly UNOX system. We are convinced that UNOX system is one of established wastewater treatment process on its treatment performance as well as economical process.
We, herein, have just made an evaluation of UNOX system based on the past achievements in pulp and paper wastewater.

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With environmental problems attracting global attention, efforts are being made in industry to protect the environment by acquiring ISO 14000 series certification and adopting industry-based control and improvement. Trends are growing in implementing Pollutant Release and Transfer Register (PRTR) laws to protect the atmosphere, in enforcing ordinances for preserving the environment through penal regulation (a first in Japan being implemented in Saitama Prefecture) and in including emission regulations for volatile organic compounds (VOC) thought to cause photochemical oxidants and suspended particulate matter in The Air Pollution Control Law in the Japanese Diet. This calls for further cooperation among enterprises.
Since preserving the global environment is a top social priority, enterprises are expected to bear the cost of measures regarding substances and low-concentration exhaust gas not yet included in emission regulations but expected to be monitored in future.
VOC (primarily high-concentration exhaust gas) are recovered or burned in attempts to save on equipment and run cost. In view of emission regulations and the work environment, however, low-concentration, high-capacity exhaust gas must also be treated. Enterprises must thus be thoroughly knowledgeable about how such exhaust gas occurs to select effective, appropriate treatment.
This paper outlines the selection of VOC treatment based on gas occurrence and the purpose of treatment. It introduces principle and features of exhaust gas treatment equipment. Representative equipment manufactured by Toyobo Co., Ltd. is given below.
K-filter solvent adsorption equipment involves fixed-floor adsorption recovery using activated carbon fiber that enables recovered solvent to be reused. Honey-rotor adsorption condensation equipment uses low-pressure-loss, high-performance adsorbent obtained by fabricating hydrophobic zeolite or activated carbon in a honeycomb configuration, condensing high-capacity, low-concentration exhaust gas into low-capacity, high-concentration gas and making after-treatment equipment compact and inexpensive. The treatment principle behind K-MATROLL is to adsorb and condense exhaust gas by rotating a belt of adsorbent activated carbon fiber before catalytically oxidizing condensed gas using compact exhaust gas treatment equipment, i.e., K-MATROLL. We recommend the above equipment for effectively treating exhaust gas case by case.

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The Regenerative Thermal Oxidizer (RTO) is one of the most efficient pollution control system available for the elimination of fumes, odors, solvents and other volatile organic compounds (VOCs) from process exhaust air of ovens, coaters, dryers, chemical systems, and similar processing equipment.
RTO is designed to burn VOCs at high temperature of 800°C to 1,000°C while minimizing operation costs. To save fuel, RTO uses the regenerative principle in which equipped ceramic media (honeycomb type) are alternately heated and cooled.
Up to 99% of the polluting VOCs are converted to harmless substance such as water and carbon dioxide by thermal oxidization, while up to 98% of the waste energy is recovered and reused for the preheating process. This RTO system has come into wide use in Europe and America since 1980’s to effective control VOCs, and recently has taken notice of the person in concern in Japan.
This paper explains briefly about the RTO technology for VOCs destruction.

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The amount of ash generating and its future prediction, and the actual condition of processing, disposal, and effective use technology on coal ash which are generated with an electric power industry are introduced. In the present condition, it is presumed that the amount of coal ashes generating increases steadily, and amounts to9million t at 2010 age. Since a limitation is in the reclamation disposal ground and an expensive waste processing expense is required when coal ashes are used for cement raw material, the valuable effective use technology should be developed immediately. Although each electric power company is developing extensive use technology in civil engineering works or a construction field energetically, an actual result in field is not gotten yet. Therefore it is necessary to develop a valuable effective use technology continuously from viewpoints, such as reliability, economical efficiency, and environmental protection.
Central Research Institute of Electric Power Industry considers “control of the amount of coal ashes generating”, “quality improvement of coal ashes”, and “the advancement of coal ashes use technology” as a technical subject which increases the valuable rate of effective use of coal ashes. The outline of research that we investigate for these subjects is introduced.

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[in Japanese]

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2004 TAPPI PAPER SUMMIT took place in Altanta, GA, USA during May 3 - 5 in 2004. Technical papers included 150 papers in the oral presentations and8papers in the poster presentations. They dealt with the topics of innovation in paper making, environment, recycling, product performance, people and infrastructure, manufacturing excellence, maintenance and reliability, and U.S. department of energy agenda 2020 R&D. In this report, innovation of filler, sizing, online sensor, and head box were reviewed.

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The optimal conditions of isothermal cooking (ITC) for the improvement of pulp yields were applied to a mill trial using mixed hardwoods, polysulfide (PS) , anthraquinone (AQ) and a continuous digester. PS cooking liquor containing 70% of total alkali and AQ (0.02%on wood) were charged into a chip-feeding circulation line, and then kraft cooking liquor containing 30% of total alkali was introduced into three circulation lines, i.e., top-cooking, bottom-cooking, and washing, where temperature reached about 130-145°C. Results from laboratory cooks of the mixed hardwoods showed that a linear correlation existed between pulp yields and ratios of xylose to glucose (X⁄G ratios) , liberated from the pulps by an acid hydrolysis. Pulp yields at a mill trial could be estimated by knowing X⁄G ratios of the mill pulps. It was indicated that the PS-AQ ITC under the optimal conditions gave pulps with 0.235X⁄G ratios at kappa number 18-19. It means that PS-AQ ITC shows about 7% higher pulp yields than laboratory kraft cooking and at least about 1.4% yield increases compared with the kraft ITC.

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