In this study, Shinshiro and Horai areas were selected as a local community with forest resources unused effectively since fraction of forest area in this community exceeded to 60%. First, tree types and their amount were investigated in those areas. Amount and types of recycled and wasted woody biomass were also investigated by hearing and questionnaires to sawmill factories in Shinshiro and Horai areas. Based on those investigation results, available amount of woody biomass to energy and material resources was estimated. Additionally, several energy production technologies such as combustion, gasification and so forth were also surveyed Consequently, a small-scale fixed bed gasifier with a gasoline engine was selected as one of the candidate. To operate this gasifier, fundamental thermal properties of the biomass selected were analyzed, and the gasification and power generation experiments were also conducted.

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Demonstration operation of the commercial plant (capacity:30tons/day for MSW) of a fluidized-bed gasification and melting system had been carried out for waste plastics and incineration ash. In this paper, we report on following results of experiment;-The operating conditions of system -Reduction of fuel consumption -Transfer rate of heavy metals -Characteristics of slag and incombustible

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The possibility of thermal recycling of wasted PET-resin has been investigated in the open atmospheric operation by supplying PET-resin powder as an auxiliary fuel to a proposed twin-fuelled burner. In the preceding experiments, in order to reduce an amount of unburnt PET-particles in the open atmospheric operation, reactive flows and burning processes of PET-particles were investigated using PIV/PTV measurements. Appearances of flying PET-particles were also observed by using the pulse laser and the particle diameter was evaluated as an equivalent diameter. According to the results, some key factors for reducing the unburnt rate of PET-particles were clarified. In this paper, by taking these factors into consideration, an experimental attempt at reducing unburnt particle emission in the recycled PET-resin powder combustion is carried out by varying the PET-powder supply pipe diameter. The result specifies experimentally that the increase in the dispersion degree of PET-particles reduces the unbunt rate of PET-powder.

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Energy recycling of wasted plastic-resin is focused in this investigation. Fine grinding of plastic-resin and preparation of high temperature oxidizing atmosphere are indispensable for effective and successful burn-up of plastic resin. Polyethylene terephthalate resin powder is employed and the high temperature oxidizing atmosphere is generated downstream the annular burner. Temperature and O_2 concentration fields downstream the annular burner are first examined by varying the slit and circular nozzle jet velocities with both equivalence ratios kept constant and without PET-powder supply. PET-powder and stoichiometric propane-air mixture are then issued into the high temperature region by varying the slit jet velocity, the nozzle jet velocity and the median diameter of PET-powder. Variation of O_2 concentration fields and isothermals due to PET-powder combustion is also evaluated the PET flame. According to the results, the relationship between the high temperature oxidizing regions and unburnt rate of PET-powder is finally discussed.

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This paper reports a waste gasification system equipped with a pyrolysis rotary kiln and gas cracker. After building a pilot plant, we advanced to construction of a demonstration plant to a commercial plant. It then became possible to realize more stable processing. In addition, a great deal of plant data was acquired. In an incinerator, heat recovery is performed after burning waste. Combustion gas is purified after that. In contrast, in a gasification system, energy is used after purifying the gasified gas. Since gasification is performed in a hot reduction atmosphere, there is a strong possibility of generating high-temperature corrosion and generation of dioxins is strictly controlled. Furthermore, although the amount of calories per unit capacity of the generated clean fuel gas is low, improved efficiency of generating electricity from waste materials is expected when using this system since it can be combined with an efficient power generation system.

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Plasma Melting Technology enables effective melting of PCB-contaminated wastes together with their container drums at one time, by using plasma arc and molten slag bath in the plasma melting furnace with plasma heat source. A series of verification tests to treat PCB-contaminated wastes are carried out in the test facility. These results offered a stable operation and discharge of homogeneous slag to be recyclable. And furthermore, the concentrations of PCBs and Dioxins in the slag, fly ash and flue gas from plasma melting furnace were substantially less than the Japanese regulations. It is proved that the Plasma Melting Technology could not only treat various PCB-contaminated wastes but also minimize the PCB contamination on environment and field workers.

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This study intends to explore the potential of a technique for producing hydrogen-rich synthesis gas from waste wood. To achieve this, a catalytic steam gasification technique is specified, where the gas product is used as fuel for molten carbonate fuel cells (MCFC). Gasification experiments were conducted in a fluidized bed using four kinds of commercially available nickel-based steam reforming catalysts. Relations between the hydrogen conversion characteristics and details of the operating parameters, including the catalyst, temperature, steam to carbon (S/C), and equivalence (ER) ratios were examined, and the catalytic performance evaluated. The synthesis characteristics of dioxins and H_2S were also examined based on environmental criteria and the MCFC tolerance. Findings included the presence of alkaline metal oxide in the Ni catalyst (G-90LDP) enhancing hydrogen conversion performance and reducing components such as tar and H_2S. Of the catalysts examined, the ability of G-90LDP containing CaO constituent to produce a synthesis gas of the maximum hydrogen concentration level (57 vol.%) and the lowest tar and H_2S concentration levels was discovered, at a temperature of 1023K. Our study thus clearly demonstrated that temperature played a dominant role in hydrogen conversion, dioxin decomposition, and tar cracking. The addition of appropriate amounts of steam and oxygen was found to have positive effects, while excessive amounts had a negative effect on hydrogen conversion.

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Mitsui Engineering & Shipbuilding Co., Ltd. recently developed the catalytic filter bag with dioxins (DXNs) decomposition catalyst (TiO2-V2O5-WO3) inserted into its center by special processing. This catalytic filter bag is specially developed for the pulse-jet type bag house. From the demonstration test results using one set of small catalytic filter bag, we confirmed that DXNs removal performance was more than 95% after 30,000 times of pulse jets and the performance deterioration was not recognized by the pulse jet. 160 sets of catalytic filter bags were fitted into the bag house of the Fluidized Bed Waste Incinerator for MSW, and the commercial operation was started. After 9 months of operation, DXNs removal performance was greater than 95%, and performance deterioration was not recognized.

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Recently, hydrocarbon refrigerant isobutane (R600a) began to be carried in household refrigerator. The proper processing technology of isobutane is required in order to prepare for recycling of the refrigerator. Isobutane below the inflammable range is oxidized to CO_2 and H_2O by using a palladium catalyst. The catalyst temperature conditions for isobutene completely oxidation were clarified. The temperature distribution of catalyst showed that 60% or more of isobutene had oxidized near the catalyst inlet.

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The aim of this work is to extend the lower limit of operating temperature of the high-temperature corrosion monitoring sensor for boiler tubes in waste incineration plants. The lower limit of operating temperature depends on the solidifying point of the electrolyte solvent of the Ag/Ag^+-type reference electrode of the sensor. The researchers obtained a modified reference electrode with a lower operating temperature by changing the electrolyte solvent from equimolar NaCl-KCl-Na_2SO_4 to 44 mol% NaCl- 56 mol% ZnCl_2. The field test in a waste incineration plant has been performed to investigate the applicability of the improved sensor. In the test, the corrosion rate of the SUS 310J1 stainless steel was measured by electrochemical impedance method at 30-minute interval, and the state of measurement was monitored by wireless communication equipment for 2,087 hours. As the result, the corrosion sensor proved to be suitable for measurement in the temperature range down to 280℃. The observed data provides the contour map of corrosion rate represented in the T_<metal>-T_<gas> coordinates, which is useful for the structural design and material selection for the boiler superheaters.

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In Japan, effective utilization of waste heat from municipal solid waste incineration plants has become very important to restrain output of CO_2. But it is difficult to use waste heat on site or very near by. Because waste heat from municipal solid waste incineration plants is too many value to use for heating and cooling applications on site. We need the method to transport waste heat to heating and cooling applications of other site. Kobe Steel Ltd. is developing latent thermal energy storage equipment for this transport system. This equipment is using Erythritol of phase change material (PCM) and direct contact heat transfer technology. Direct contact heat transfer technology is heat exchange method contacted heat medium to PCM. The advantages are high performances of heat input and heat output, light weight equipment by no heat exchanger. In order to estimate the performance of this system, two sets of thermal energy storage experiment, 15kg and 400kg of erythritol were carried out. As a result, stable operation of the two set systems and high performance were obtained.

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This paper describes the characteristics of modified sulfur-solidified material (MSSM, hereafter). Modified sulfur works as a binder in MSSM bonding several kinds of aggregates such as blast-furnace slag, converter slag, electric-furnace slag, liquid slag and, furthermore, various seashells. MSSM, compared with the ordinary cement concrete, is highly dense, strong, abrasion-resistant, resistant to salts and acids, and has a high affinity for animate beings such as seaweed. MSSM can be used, for example, as fish banks, algal reefs and wave-dissipating blocks, and as repairing material exposed in highly acidic environment.

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Various systems are developed, and have been put to practical use in the ash processing and the flue gas processing. Our company gets the operation results of two years in the facility with the system that processes flue gas with 2-stage (normal and catalytic) bug filter and melts the dry ash. The mass balance and the amount of a total exhaust dioxins for each ton of municipal solid waste were calculated with the report of the operation results in this research, and the superiority was verified.

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The quality of concrete has been investigated empirically, when three kinds of waste melting incinerator slag, direct-arc, fluidized bed gasification and coke bed type is used as pulverized aggregate. It has become clear that bending strength and freeze-thaw of Iterlocking Block that contains slag stay within the normal range, if the ratio of slag substituted for sand is around 10%. There is no evidence of efflux of heavy-metal ion, such as Cu, Cd, Se, Ag, etc., from slag and the Iterlocking Block.

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In recent years, the air pollution problems and the influence to human which is caused by NOx and PM from diesel engine exhaust gas become severe social problems. More effective post-processing technology is desired. Although the use of DPF is now a leading technology for PM removal, the problem exists on the soot incineration or regeneration at low temperature. In the present study, a regeneration of DPF using ozone generator, and removal of NOx after DPF using ozone generator with the Na_2SO_3 was investigated. The targets are stationary and marine diesel engines. As a result, the regeneration of DPF could be confirmed, and NOx could be removed by 75%.

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The pilot-scale NOx removal from boiler emission was performed using our proposed indirect plasma and a chemical hybrid process. The flue gas flow rate was in the range of 450〜1,470m^3_N/hr, the gas temperature of 280℃, and NOx concentration of 30ppm for gas firing and 70ppm for oil firing, respectively. The NO_2 oxidized by the indirect plasma was further reduced by a Na_2SO_3 solution chemical scrubber to N_2. The NOx removal efficiency for gas firing exceeded 90%. It was known that the quality of wastewater was proved to be disposable.

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A technique for removing the NOx contained in combustion exhaust gas has been developed by using radicals produced in the arc plasma. The gas mixture of plasma operating gas Ar or N_2 and reducing agents such as H_2, diesel fuel and NH_3 are feeding into arc plasma torch. Radicals such as NH_2, NH, HC, N, H produced in plasma jet are mixed with the simulated exhaust gas (N_2+O_2+NO) in the reactor. The NO decreases as a result of the formation of the innocuous products N_2 and O_2 when O_2 is not contained in the exhaust gas, while the NOx increases with increasing input power to plasma in an oxygen-rich gas. The effects of plasma operating gas, input voltage and power to plasma, reduction agency, mixing position of radicals with exhaust gas, and O_2% contained in exhaust gas on the NOx removal rate are investigated experimentally. Also discussed are the usability of the hydrogen and the diesel fuel as reducing agent, as well as availability for a selective reduction process of NOx by ammonia.

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Electrical discharge process using corona is effective in reducing particulate matter (PM), nitrogen oxides (NOx) and total hydrocarbon (THC) contained in diesel engine exhaust. We experimentally evaluate the application of DC corona discharge reactor to reduce the PM, NOx and THC from diesel exhaust. Particulate trapping in a corona reactor can be accomplished by electrostatic precipitation. The accumulated PM on a nichrome electrode of reactor can be regenerated by the controlled burning process. In a corona reactor, NO is oxidized to NO_2 and NO_2 reacts with H_2O contained in exhaust. NOx decreases as a result of HNO_3 formation in a reactor, and successively HNO_3 is neutralized on the filter paper contained alkali. A corona reactor consists of cylindrically-shaped outer electrode made of stainless steel and central electrode made of rolled nichrome wire. In this study, the effects of corona voltage, current and the space velocity of reactor on soot collection efficiency, NOx removal rate and THC reduction rate are investigated. Also discussed is the particle size distribution of soot collected by a reactor.

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In this study, experimental and numerical analyses have been adopted to clarify the key radical of the VOC decomposition process. In experimental analysis, it is clarified that the DBD system decompose the methanol and styrene completely. Those characteristics are also numerically analyzed using conservation equations of mass, chemical component, momentum and energy. In numerical analysis, it is suggested that OH is an important radical to decompose the methanol.

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Ammonia radicals were produced in a radical injector using an intermittent one cycle pulsed power source were injected into simulation gas (NO/O_2/N_2). NO was removed efficiently by ammonia radicals which were externally generated by flowing the NH_3 gas diluted with Ar gas through a dielectric barrier discharge (DBD). In order to find optimum parameters for NO reduction and energy efficiency, the reaction temperature, the applied voltage, the NO gas concentration, and the ammonia concentration and flow rate were varied. A maximum energy efficiency of 40g/kWh at a NOx reduction of over 99% is obtained under the optimum condition.

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Formation/decomposition mechanisms of PCDDs and PCDFs were investigated in combustion experiments of model wastes using a laboratory-scale fluidized-bed reactor with a high-temperature hold section at 600℃. The temperature-hold section was equipped after a furnace for the reduction of the PCDD/F emission. The amounts of PCDDs and PCDFs formed were reduced and their homologue profiles were shifted toward lower chlorinated species at downstream sampling points in the temperature-hold section. The ratios of the concentrations of PCDD congeners at the downstream sampling points to those at the inlet point in the temperature-hold section were more dispersed than those of PCDF congeners. This may indicate that PCDDs are decomposed through dechlorination reactions more than PCDFs in these experiments. In addition, the condensation reaction of precursors such as chlorophenol was observed in the PCDD congener distributions. The condensation reaction is not negligible in the various pathways of PCDD formation/decomposition in this temperature range. The PCDF congener formed through the dechlorination reaction after the formation from carbon/PAHs was observed in their congener proportions. These results show that the PCDD/F formation reactions occur in parallel with their decomposition reactions and the reactions have a different dependence on experimental conditions.

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This paper presents a nolinear model-based predictive control to the de NOx system for the ST-BT combined cycle plants. The aim is to improve the existing PID controller by reducing the amount of ammonia to be applied. Implementing the RBF-ARX model based Predictive controller on the existing PID controllers, we found that the standard deviation of controlled NOx around the set-point was considerably reduced.

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A new diesel particulate filter (DPF) using ceramic paper has been developed to clean flue gas from diesel power generation. It can drastically remove particulate matter (PM) discharged from stack even in start-up operation. Removal efficiency is more than 90%. Another feature is its low pressure drop, less than half of a conventional ceramic honeycomb DPF. Filter plugging, which is seen in a conventional DPF system, can be solved by combining this new DPF with catalyst technologies.

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Experiments have been carried out to develop the high efficiency combustion burner which is achieved the energy saving and low CO_2 emission by utilization of the infrared rays of 4 to 1000μm in wave lengthen. It is well known that the lower hydrocarbon fuels such as methane can absorb much infrared rays at the wave lengthen of around 8μm. These rays may contribute to promote more collision behavior between fuel molecular and oxidizer, and consequently the flame temperature gives rise to increase. The acquisitions of experimental data are as follows: (1) the average flame temperature during combustion brings about the temperature rise of about 50℃ by utilization of the energy seat which can emitted much infrared rays and (2) the energy saving rate obtained in the study is approximately 15% when the energy seat is attached in combustion burner.

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Experiment has been conducted to assess the emissions of CO, CO_2 and NOx which are produced by combustion of solid waste fuels in flowing high temperature burnt gas. The food of Nishiki-Koi (Japanese color carp) is used as standard test fuels because its composition and elements are very much similar to those of RDF and town gas. The configuration of the test fuel is the cylindrical shape of 20mm in diameter and 50mm in length and the ambient temperature and gas velocity, which are produced from the flat flame burner, are about 250℃ to 350℃ and 1.0m/s, respectively. The ignition of solid waste fuel is done by small nichrom wire and stable combustion of cylindrical solid waste fuels can be maintained during combustion process. The emissions of exhaust gas are measured by NAO gas analyzer. The main results obtained in the study are as follows: (1) though the emission of CO decreases with increasing ambient temperature and the emission of CO_2 increases with increasing ambient temperature, it is very difficult to achieve the complete combustion at less than 350℃ of ambient temperature and (2) the emission of NOx produced by waste fuel combustion increases with increasing ambient temperature even at lower oxygen concentration and this may be indicated that nitrogen components containing in waste fuels may be contributed to produce the emission of NOx.

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New method of hydrogen production by mechano-chemical reaction of various metals (Al, Si, Fe, Ni, Pb, Ti, Cu, Cr and Co) with water was investigated. Capacity of hydrogen production were correlated to the standard free energy (&lrtri;G°) of metal oxides formation. It was revealed that aluminum had the highest hydrogen production capability among various metals. However, there was a long induction period in the reaction of Al with water. This induction period was decreased by the addition of high hardness materials such as SiC and Cr. It was concluded that the oxide layer on Al surface was effectively destroyed by the increase of collision frequency between Al particles and high hardness materials.

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Catalytic activities of ruthenium (Ru) supported on various carries such as carbons (C), metal oxides (MOx) and Y zeolites for hydrodechlorination of PCB-related compound (chlorobenzene; Cl-B) were investigated in order to develop safety and reasonable treatment of PCB compounds. It was found that Ru supported on acidic carriers such as acidic active carbon, SiO_2・Al_2O_3 and HY showed high activities for HDC of Cl-B. Therefore, we concluded that Ru particle on acidic carrier acts as active site for activation of hydrogen to form spillover hydrogen and acid site on carrier acts as active site for activation of Cl-B in HDC of Cl-B.

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When the membrane filtration is applied to the middle or large-scale water purification plant, the establishment of a higher recovery and a more efficient operation and on-site chemical cleaning etc. is being requied by a system now at the time of be spreading around a small-scale water purification plant. Subjects this study as following: (1) Improvement in the water-purifying recovery rate by construction of a multi-stage membrane filtration system (2) Improvement in the stability and the water-purifying performance of the total membrane filtration system and the membrane filtration of each stage (3) Development and establishment of the chemical cleaning method, and examination of the non-chemical cleaning method For the purpose of establishing the membrane filtration water-purifying system, it is an energy-saving and space-saving type at 100.000m^3/day scale, the actual proof experiment is executed. This paper reports the outline of this system and the result obtained until now.

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Membrane filtration process has been introduced to many small water purification plants to fulfill the growing demands of cryptosporidium-free water, rationalized operation and maintenance, and dealing with polluted water source. Recently, introduction of membrane filtration process is to being considered by larger purification plants. For those cases, it is required not only small footprints or high water recovery, but also capability of on-site chemical cleaning of the process. Authors performed a demonstration experiment using pilot scale plant equipped with monolith ceramic MF membrane for put this process to practical use in larger plants. As a result, it was demonstrated that the plant has been operated stably under a flux of 4m/d, with periodical chemical cleaning about once in five month, and water recovery rate was 99.9%.

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The discharge into the sea of noxious liquid substances or tank washings contains such substances should be prohibited to protect marine environment from pollution produced by ships. In order to facilitate the dealing with the wash-water, it is necessary to reduce the generation rate of tank cleaning waste-water of the noxious liquid substances tanker. And it can reduce the sea disposal of cleaning waste-water. The wash-water quantity can be reduced by decreasing nozzle caliber of the washing machine and making the minute scanning line. Model tank and from 0.5mm to 3.0mm caliber nozzles were used on the experiment. The concentration under cleaning drainage of the water for washing quantity was obtained by the experiment, and the effect of the cleaning was evaluated. By making the nozzle caliber at about 2.5mm, it is clarified that the wash water quantity could be reduced.

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Experiments were carried out using the liquid-waste treatment system which combines the ozone system using micro bubbles with a private sewerage system to treat restaurant kitchen wastewater. When the system works at its best the amount of generated scum is decreased about 75% compared with the existing system. The maintenance cost is also decreased about 15%. This system is able to increase the deodorizing capability by increasing the amount of ozone. However, optimum amount of ozone does exist, as the oxidation of fat and oil accelerates the production of formaldehydes.

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Sewage water scooped up from the primary sedimentation tank has been purified in the reactor tank containing nitrifier and the titanium dioxide porous photocatalyst. The time course of POC, DOC, ammonium ion, nitrite ion, and nitrate ion concentrations in sewage during the batch processing and the consecutive processing has been examined for a week. The rapid decrease of POC in the sewage water during the first 15 hours is shown to be dominantly due to the absorption by porous material. POC is decreased from 30〜45 ppm to 〜5ppm and DOC from 40〜60 ppm to 10ppm in 7 days because of the effect of absorption and processing by the porous photocatalyst. Ammonium ion is nitrified to nitrate ion in the reactor tank, showing that nitrifier coexists with photocatalyst and that porous photocatalyst promotes ammonium nitrification. Ammonium ion was nitrified to nitrite ion, and nitrate ion in the reactor. The nitrified sewage water has been kept for 4 days in the aerating reactor tank with the porous material containing denitrifier to examine the time course of nitrite ion, and nitrate ion concentrations. It is shown that denitrification is achieved even in the aerobic state and that the efficiency of denitrification depends on the size of porous material.

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We examined the influence that the temperature change in the city exerted on the O_x concentration. Investigation result of recent observation, it was shown that the temperature and the quantity of solar radiation were positive relations against of O_x concentration observation. In addition, the impact that the temperature rise of 1℃ gave to the O_x concentration was investigated by using a numeric model. As a result, it was shown that it was roughly the same quantitatively tendency compared with the observation result. Moreover, it was shown that the influence that biogenic VOCs increase and decrease exerted on the change in the O_x concentration was strong.

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Life cycle inventories (LCIs), those are the backbone of life cycle assessment (LCA), have been developed principally from the point of view of global warming issue, such as the allocation of the emission of carbon dioxide, until now. On the other hand, as PRTR (Pollutant Release and Transfer Register) was executed in 1999, widely corrected data on emissions of various minor pollutants have become available for a variety of environmental impact assessments. Then, the introduction of PRTR reports into conventional LCIs can be effective to diversify environmental impact assessments in LCA. In the present study, several procedures to introduce PRTR reports into LCI are investigated for petroleum refinery process.

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We experimentally evaluate a performance and exhaust emissions of a single-cylinder, four stroke direct injection diesel engine operating on Rice oil methyl ester (Rice oil BDF), Mixed waste food oil methyl ester (Recycle BDF), Recycle BDF adding 500wt ppm Ferrocene (Re-BDF+Fe) and adding 500wt ppm Cerium Mixed (Re-BDF+Ce). The combustion characteristics, emissions such as NOx, CO, HC, O_2, CO_2, smoke, particle size distribution and first stage durability test are compared with the case of JIS # 2 gas oil. We found that (1) the NOx emissions of Rice and Recycle BDF are slightly higher than gas oil in the almost load range. Though NOx emissions of BDF+Fe is as same as base fuel gas oil in the whole range. (2) CO and Smoke emissions of BDF fuels are lower than gas oil especially in the high load range. (3) PM emissions of Recycle BDF is 1/2 times its gas oil. In case of Re-BDF+Ce and Fe are higher than Recycle BDF.

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A mild mixing technology is suitable for the stir of microorganism, which is weak to the shearing. Taylor vortex flow (TVF) is one of the important candidates for mild stir mixture, and in this study, the cultivation in the TVF is examined with a small aspect ratio. As the result of cultivating the microorganism in TVF, it was found that the multiplication characteristics and oxygen production ability were related to the Reynolds number and the sedimentation rate with coagulation. An effect appeared with the proliferation in TVF though the coagulating sedimentation of the cell would be originally unsuitable to proliferation.

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Experiments were carried out using the cavitation type liquid-waste treatment system with ozone to treat food-industry wastewater. The highly efficient gas solution system employing a friction panel at the tip of a nozzle improves the dissolution efficiency by decreasing the diameter of bubbles to 1/100 of that of the existing air blow system. When organic soil pollutions were treated, the values of first-order rate constant that are Dichloromethane, Trichloroethylene, and Tetrachloroethylene were 0.9287, 2.5136, and 2.452380 respectively within thirty minutes. This system has also been proved to be more effective than the aerator for water containing VOC and Thiuram. When the system treats 1000 ton of water which is polluted 100 times more than the environmental standard values, the estimated cost 20 million yen and the processing time would be about a month.

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In recent years, global warming becomes a big problem and the reduction of carbon dioxide (CO_2), which is typical of greenhouse gases, is required. Therefore two reduction methods are proposed. Namely, Type 1: Liquid CO_2 is covered with CO_2 hydrate, and is stored at the bottom of the deep sea. Type 2: CO_2 is dissolved in seawater and is diffused in the sea. However, a simulator that can predict the behavior of CO_2 in the current accurately does not exist. This paper proposes an agent-oriented simulator for estimating the behavior of CO_2 in the current and the detail of the system is described. CO_2, pipe, sea that are the essentials of this simulation are defined as the agent, respectively. This simulator has been developed by Java language and common agent classes are provided by us, and the operation has been confirmed through test cases. The result obtained from the test cases shows that the proposed simulator is suitable for estimating behavior of CO_2.

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Chemical tankers in Japan transport various kinds and large amount of chemical substance. Some of them have adverse effects to the human health condition. However they are VOC (Volatile Organic Compound) and vapor gas in cargo tanks emits into the atmospheric environment during loading operation and tank cleaning operation that is conducted to avoid contamination with next cargo. In this paper, the emission amount of transported cargoes from chemical tanker in Japan is estimated with calculation models. Furthermore, to evaluate the pollution level of benzene, recognized as carcinogen, caused from chemical tanker activities in the Tokyo bay, the yearly averaged concentration distribution was calculated with atmospheric dispersion analysis. It was found form the analysis that the contribution ratio of chemical tanker to atmospheric concentration of benzene around Tokyo Bay area is 10% approximately.

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Numerical simulations of blast wave generation and its propagation over a real terrain have been carried out. Based on the numerical results, more specifically the maximum overpressure distribution on the ground surface, a hazard map of blast wave damages was created for a fictitious eruption of Mt. Fuji. It demonstrates the usefulness of numerical simulations for establishing safety measures against volcanic hazards. Numerical simulations for investigating the generation of pyroclastic surge are also carried out.

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Forest in Siberia plays important role for absorbing carbon dioxide. However, resent increase in forest fires, due to both human negligence and global warming, appears to cause significant damage on the forest. The present research tries to establish simulation model, which enables to predict forest fire effect over thousand years, and to evaluate the effects of forest fire on long term balance of CO_2 in Siberia. The result of the analysis shows that the major factor affecting on long-term forest area is the probability of fire extension and the number of fires in a year would not make apparent difference in the forest area due to feedback mechanism of fire sizes. The prediction was confirmed by the analysis of the remote sensing data. The paper shows the substantial danger of global warming effect on long-term forest area, whereas human negligence effect may be small.

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In this paper, an improved method was produced by incorporating a new control behavior model which was developed with the results of survey on the usage of air conditioner and radiation calculation model which considered surrounding buildings shade. By applying the improved method, air conditioning method and energy consumption were evaluated with 3 cases (Case 1: no surrounding buildings, Case 2: check layout, Case 3: brick layout). Consequently, in comparison with Case 1, the total cooling energy consumption in the living room reduced by 11% in Case 2 and by 15% in Case 3, while the cross ventilation duration in the living room increased by 5% in Case 2 and by 6% in Case 3. It is suggested that in Case 2 and Case 3, the solar radiation absorbed by inner and outer walls was reduced by surrounding buildings shade, thus resulting in decrease of total cooling energy cosumption.

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The countermeasures of heat island phenomena; groundwater use, tree planting, albedo value and location of heat emission; were investigated by 3-dimensional simulation model. It was found that groundwater use was sensitive to the comfortable index such as mean radiative temperature, ET and WBGT, that tree planting on the south part, which intercepts the sunlight, was effective and that heat emission from the roof was adequate in case of the deep canopy height.

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This report described completion of anthropogenic waste heat database around Kinki region and effect of the anthropogenic waste heat upon urban thermal environment. (i) At seaside area where industrial zone is situated, waste heat from industrial sector contributes most to total waste heat. In Osaka and Hyogo area, most of the waste heat comes from residential and commercial sector and transportation sector. On the other hand, amount of waste heat released in Kyoto, Shiga and Nara area are comparatively low. (ii) During night, the increase in temperature is about three time larger than that during daytime, though the amount of anthropogenic waste heat is less than that during daytime. (iii) The waste heat from residential and commercial sector and transportation sector contributes to the temperature rise more greatly than that from industrial sector. (iv) In evaluating urban thermal environment, the anthropogenic waste heat database is indispensable.

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We make indoor model experiments of hydrological cycling type snow melting system by the use geothermal energy with drilling hole. We report the results of some measurements on the temperature of free convection circulating water and snow melt rate. The following results are inferred: 1) In inner pipe, two water current directions of ascending or descending ones are observed under free convection circulation. 2) The muximum convection circulation speed of 11.8cm/min is inferred. 3) The minimum workable temperature is 5℃ for the system. 4) The penetration of an aquifer for warming pipe is useful to run the system.

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Three types of solar system for hot water supply of middle temperature over 80℃ are developed. The collection performance between a collector with non-reflective pair-glass of high temperature and the other two collectors with normal single-glass was compared each other. Collector A of normal-glass, collector B of non-reflective pair-glass and collector C of vacuumed pair-glass were prepared for the test. A solar system, which consisted of the collector B, was simulated under the Sapporo weather conditions due to METPV-2 data. As the result, a heat transfer coefficient of the collector A was 3.27W/m^2K, and those of the collectors B was 2.51W/m^2K and C was 1.71W/m^2K respectively. The rate of the heat transfer coefficient for the collector B to the collector A was 77%, and however, that of the collector C to the collector A was decreased to 52%.

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To utilize solar energy, an estimation method of daily insolation irradiance on the tilt surface was derived from daily global insolation. In order to satisfy this requirement, comparison with calculated tilt insolation by a lot of meteorological data with calculated tilt insolation by METPV-2 data at twelve locations. By using this method, the daily tilt insolations were estimated accurately. Locations for the calculation are as follows: Sapporo, Nemuro, Akita, Miyako, Matsumoto, Wajima, Shionomisaki, Yonago, Shimizu, Fukuoka, Kagoshima and Naha. Consequently, using daily global insolation data, an estimation equation for the daily tilt insolation can be obtained.

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A heating and / or hot-water supply system for residential houses composed of a decompressed-boiling solar panel, heat pump, and hot water storage is proposed as a strong measure for reducing domestic energy consumption and CO_2 emissions from our group. To aiming at development of the actually effective system, we constructed a decompressed-boiling solar panel to be used as an evaporator of heat pump. We tested the performance of decompressed-boiling solar panel on the roof of library in Keio university and confirmed the high solar-thermal-energy collection ability, 47-102%, from 13 day experiments. We concluded on the basis of the data obtained in this study that the energy saving effect in the case of the decompressed-boiling solar panel used as an evaporator of heat pump would work.

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A room heating method that uses an air conditioner together with a unique floor heating system is proposed. The floor heating system is composed of 32 polyethylene tanks with total water of 6726 and vinyl tube of 200m in length under the floor (10m^2). The water heated by solar collectors flowed though the tube. When two collectors with the total collector area of 4m^2 were used, the temperature of the floor surface became 2 or 3℃ higher than the room temperature at 22℃. When the operation of the air conditioner was off in the midnight, the floor temperature dropped, but it remained at 14℃ in the early morning when the ambient air temperature was 2℃.

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Optical multilayer coatings are able to control the solar energy by means of the multiple interference of light. In this paper, the optimum structure of the multilayer coatings is designed to achieve the target spectrum characteristic for using window pane both as summer season and winter season. Three cases of the structure of the window pane with a certain number of thin film layers - in case of the films are coated on the front side, the both sides or the back side are examined. The plural incident angles of sunlight is considered. The results of optimum design results and comparing the three cases in some patterns are shown.

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