We have developed the combustion furnace for pulverized wooden charcoal .Wooden charcoal has similar properties of Anthracite. It has a little volatile matter and a lot of fixed carbon. It was expected that it is difficult to combust it stably. It is important for stable combustion of wooden charcoal to describe as follows. (1) Even solid fuel including a little volatile matter can be combusted stably (2)Temperature of furnace wall is always kept lower than the softening point of fly ash from wooden charcoal combustion and slagging must be controlled (3) Growth of NOx in the high temperature combustion zone msut be restrained. We have achieved the development of the combustion furnace for pulverized wooden charcoal with abilities of controlling slagging and growth of NOx by way of slow combustion and flue gas recirculation and in-furnace NOx reduction.

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This paper describes the application of innovative hydrothermal technology on local municipal solid waste (MSW) to produce low chlorine content solid co-firing fuel with coal. Raw MSW was treated at temperatures ranging from 210 to 235℃ with 30 to 90 minutes holding period. The process yielded slump products which were then naturally dried to 5% moisture content, resulted in dry products with the heating value up to 24MJ/kg (dry base). Organic chlorine compound from plastic in MSW was converted to inorganic chlorine and reduced to 0.2% level. The inorganic chlorine substances were then removable by water washing at 1:8 product-water ratio (dry base) and vacuum filtration. With these features, the innovative hydrothermal treatment would then be a good alternative for MSW treatment and conversion into coal co-firing fuel.

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This study aims at investigating the influence of hydrothermally treated municipal solid waste (MSW) on co-combustion characteristics of different rank coal. MSW blends of various proportions (on %wt), with different rank coal were tested in a Thermogravimetric analyzer (TGA). Combustion characteristics like volatile release, ignition were studied. The result shows that even though the blending of MSW with coal is favorable to initiate the early release of volatile, different ignition behavior was observed depending on the blends composition and coal rank. It is found that the effect of early volatile release by MSW on coal ignition differs and depends on quality of coal. The TGA combustion profiles showed that the combustion characteristics of some of the blends can be predicted from the weighted sum of the blend components. These experimental results help to understand and gain confidence among plant operators to promote MSW as an energy source for blending with coal.

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Ground benzene-pollution is a significant environmental concern. However, large amounts of energy are required for the cleanup of the ground since the water contained in the soil hinder the extraction processes that use hydrophobic organic solvents. The proposed technology is a new concept that aims at energy-efficient cleanup for benzene-polluted soil by the use of liquefied DME (dimethyl ether) gas, which is eco-friendly, as an extractant. The saturated pressure of DME is moderate-0.51 MPa at 20℃. Liquefied DME resolves high volume organic contaminants and water. We successfully removed almost perfectly benzene from wet soil by using liquefied DME. Moreover, we succeeded cleanup by using DME deteriorated by much benzene and water. This implies that DME saturated by water achieve full effect to extract benzene from wet soil.

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This paper was intended to study characteristics of destruction of polychlorinated biphenyls(PCBs) under the condition of dechlorinatioa. The destruction experiments of PCBs were carried out with the different condition of temperature and adding amount of metallic sodium. The optimum conditions for application to the pilot scale were extracted from this basic experiments.

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From a viewpoint of the weight reduction effect in saving energy consumption, Magnesium (Mg) alloy is one of useful Eco-materials because of its high specific strength due to a low density of about 1.7 g/cm^3. On the other hand, Mg alloy requires a little energy consumption in re-melting the scraps compared to aluminum alloys. Machined chips from magnesium products, however, are not suitable for the recycling process by re-melting because they are combustible. In this study, "Up-grade recycling system in solid-state" has been developed to produce wrought strengthened magnesium alloys with a high strength and ductility via Roll-Compaction (RCP) process. In-house wastes or scraps of AMX602 (Mg-6%AI-0.2%Mn-2%Ca) alloy chips in machining the gate bar used in Electronic Toll Collection (ETC) High-way System were employed as input materials in the present study. For example, when applying RCP technique, tensile strength and elongation of AMX602 is 372MPa and 14.8 %, respectively. They are extremely good compared to the original material with 289MPa T.S and 19.2% elongation.

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A carbon/silica composite (CSC) was fabricated from rice husk (RH). RH was pulverized by using a planetary ball mill, then carbonized and molded into the precursor by means of hot-pressing without using any binders. A compression of 100 MPa was intermittently applied to the RH powder heated from room temperature to 150℃, and then to 280℃. The CSCs were produced sintering the precursor at 800, 1000, 1200 and 1400℃ without compression in nitrogen gas. The CSC sintering at 800℃ for 1 h provided the maximum bulk density of 1.52 g/cm^3 and the maximum Vickers hardness of 343. The maximum compressive strength was measured to be 55.7 MPa at the sintering temperature of 1200℃. The CSC sintered at 1000℃ showed the coefficient of static friction of 0.15 and the coefficient of dynamic friction of 0.05.

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A composite material of carbon/silica/carbon-fiber was fabricated from agricultural waste of rice husk and industrial waste of carbon fiber. Rice husk was pulverized by using a planetary ball mill. The powder of rice husk mixed with chopped carbon fiber (average length: 242μm, addition level : 10 mass%) was molded into a disk by means of hot-pressing in an inert condition without using any binders. A compression of 100 MPa was intermittently applied to the mixed which was heated from room temperature to 150℃, and then at 280℃. The molded was further heated to 300, 400, 500, or 1000℃ in an inert condition for sintering, providing a composite of carbon/silica/carbon-fiber. The composite added with 10 mass% of chopped carbon fiber and sintered at 300℃ displayed the highest compressive strength of 120 MPa and low bulk density of 1.25 g/cm^3.

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To construct the Sustainable Society, the importance of consideration to 3R (Reduce , Reuse , Recycle) in the design phase increases in various industrial products. Concerning Reuse and Recycle, the improvement of the disassembly property is important. Then we develop the quantity disassembly property assessment method Disassembly Property Index (DPI), one of the DfE (Design for Environment) supporting tool. Additionally, the quantitative environmental load assessment is also necessary to achieve the sustainable society. Though various LCA (Life Cycle Assessment) method is developed for such a demand, it is pointed out that there are a lot of problems in existing LCA. To solve such problems, Eco-Efficiency Potential Assessment (E2-PA) is developed. E2-PA is based on the concept of "Eco-Efficiency" and the "Potential Assessment". In this paper, we pay attention to Domestic Appliances (SDA) including digital cameras. Recently, digital cameras are produced and wasted in large quantities, therefore, it is hoped to be recycled. Then, we examine the consideration of 3R and environmental load assessment about them.

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As our society changes from the type of mass consumption to that of recycling, the law for the promotion of effective utilization of resources was prepared early in 2000. With this, in 2002, put into force was the Law for the Promotion of Utilization of Recyclable Construction Resources. Under this law, wooden wastes recycling plants are in operation. However, erosion has become a serious on - site problem. This paper describes erosion phenomena in wooden wastes recycling plant. As in practical recycling plants, SUS304 is very often used at parts violently affected by erosion, we make a report on the erosion characteristics of SUS 304. We make a report on erosion in recycling plants where wooden wastes can be reproduced into a particleboard, and on the influence of the impingement angle and velocity of chips upon erosion. In addition, observing the eroded surfaces with SEM, we have examined the mechanism of erosion in this recycling plant.

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This paper describes the outline of the new method for lead reduction in ash. Ash from incinerator includes various pollutants, especially lead. We can restraint leaching of heavy metals from ash through ash roasting system. Then we developed the new method for lead reduction in ash, applied chlorination volatilization technology. Plumhic oxide in ashes are reacted to chlorination lead, and volatilize to gas through roasting furnace at high temperature over 1000℃. Demonstration testing verified that (1) lead content in ash can be decreased below the standard for soil (150mg/kg), (2) the increase of HC1 and dioxins in gas can be reducted by normal gas treatment systems.

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We have worked on the fuel expenses reduction of the fuel melting furnace. We are developing two methods as the running reduction method. They are the method of mixing the combustible such as waste plastics with the being melted waste and the method of the conversion and the addition to another fuel. We report about the result of combustible mixing test at the real operation plant (Waste Treatment Center in Yokkaichi City, Mie Prefecture) and the fuel expenses decrease trial calculation result based on the test result.

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The present study aims at the development of a reliable and efficient operation principle of the melting furnace for the combined treatment process of asbestos wastes with incineration ashes. A simple method to measure the molten slag fluidity was proposed, which can be applied on site. Three series of the verification tests using the actual ash-melting furnace of industrial solid wastes was carried out. It was confirmed that the proposed technology was effective to control the slag composition in the melting operation for actual wastes. It can treat safely and reliably asbestos wastes without residual asbestos in waste gas, slag, fly ash and working environment during the furnace operation. Further, it was confirmed that the formed slag was possible to recycle-use as construction materials and so on.

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Refuse Derived Fuel ("RDF" as follows.) system has been promoted as an anti-dioxin measure and one of the refuse disposal system technology to contribute to the formation of the recycling society by the utilization of the biomass energy. However, with an explosion accident in the RDF silo of August, 2003, the promotion was delayed, and the recent fire of a wood pellet storing silo in Sweden, are being reported. Therefore, it is necessary to understand the heat physical properties of RDF when it is stored in large quantity for a long term, and an appropriate management of the fuel is crucial. This paper introduces the safety evaluation technique that can be applied to RDF

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Refuse Derived Fuel ("RDF" as follows.) system has been promoted as an anti-dioxin measure and one of the refuse disposal system technology to contribute to the formation of the recycling society by the utilization of the biomass energy. However, with an explosion accident in the RDF silo of August, 2003, the promotion was delayed. The Oomuta Recycle Power Station is continuing high efficiency generation by the RDF smoothly afterwards and we carried out various kinds of examinations and various scientific knowledge was accumulated about safety measures about the RDF storage. By this report, we speak the effectiveness of safety measures carrying out mainly on the inspection test result at the Oomuta Recycle Power Station.

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High-speed direct observations of the multiphase process in a micro particle of polyethylene terephthalate resin (abbreviated to PET in the following) under abrupt heating are made along with stereoscopic imaging of solid residuals. High-speed reflection images and stereoscopic images give conclusive evidence of occurrence of multiple micro-bubbling within the PET droplet, which is triggered by thermal decomposition of PET resin and flash vaporization of the decomposed products. Multiple and irregular explosions of micro bubbles follow just after the internal bubbling and cause irregular and random micro jets, resulting in randomly fluctuating micro diffusion flames downstream of the micro jets. It is concluded that the key factor to such a high expansion rate of the particle diameter as exceeds that due to thermal expansion can be attributed to the multiphase process due to the multiple and internal flash vaporization of thermally decomposed products, being particular to plastic resin combustion.

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The purpose of this study is to investigate the behavior of biomass gasification in the packed-bed, conducting gasification experiment and analysis of syn-gas in the reactor. In this study, pellets of black pine (ψ6.5mm×8.5mm) are fed intermittently with air as the gasification agent. The gasification experiments were carried out by two type gasification methods, such as updraft and downdraft setups. In the gasification tests, the temperature distribution in the gasification reactor and the gas compositions are measured and analyzed during gasification by thermo-couples inserted from a furnace wall and a micro gas chromatograph, respectively. Product gas before cooling were sampled for determine the amount of tar generation.

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Wastes are defined as a new energy and desired to utilize an energy source beneficially. The authors pay attention to better utilization of wastes, which is a method to convert wastes into energy, and present a waste incineration and power generation system constructed by an incinerator and a Stirling engine generator. The incinerator has a maximum incineration capacity of 49kg/h and is cooled by circulating water in the side walls in order to enable a long life and supply heat by a hot water or air flow. The Stirling engine generator is built up as a 2 piston type engine with driving mechanism including a PM synchronous generator, and is installed in a secondary combustion space of the incinerator and heated by combustion gas and an auxiliary kerosene burner. The system is forecast to have power generation of 5kW and heat supply capacity of 72kW. The waste incineration and power generation system is suitable for service use, because of waste management and energy cost reduction. Also it is effective in environmental preservation and saving energy.

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Blasting is a surface processing technique in which spherical or granular materials made of metals or ceramics are jetted against substrate surface using compressed air. In this process, high speed colliding of blasting materials against the substrate surface produces crush the materials into fine particle which affect the durability of blast materials. However, there are no reliable investigations that consider influence of the durability of blast materials. This study investigated blast materials durability by examining relation between blast counts with particle distribution and changes in blast materials properties. Results from this investigation are summarized as follows: Particle size rapidly decrease with increase of blast counts. As a result, the removal quantity and surface roughness of substrate rapidly decreased.

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About the present Japan-wide municipal waste treatment system including the containers and packaging recycling, the flow of the waste, the construction and maintaining cost and the CO_2 emissions were evaluated by combining the official announcement data of the public organization in the Ministry of the Environment and so on. Furthermore, as for the waste plastic thermal recovery system as well, in which the incineration residue was melted using waste plastic as fuel, similar evaluation was made, and the comparison with the present system was done about the cost, the CO_2 emissions and the amount of final disposal.

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We established the system to evaluate 1) Flow diagram of waste treatment, 2) Cost of waste treatment and 3) Volume of CO_2 emission comprehensively based on the published data and documents on the municipal waste treatment and the containers and packaging recycle in each prefecture and municipality available from various official bodies. By using this system, we studied the two cases of 1) Existing system and 2) Conversion of waste plastics into fuel + Melting treatment system. We concluded that the conversion of waste plastics into fuel for melting treatment enables us to realize a rational waste treatment system which minimizes landfill disposal and doesn't change the waste treatment cost and the CO_2 emission volume so mush.

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Recent years, global environmental problems have become aggravated, and a change of a personal lifestyle is demanded. We suggest LSA (Life Style Assessment) as technique to evaluate environmental load quantitatively of a lifestyle by applying LCA (Life Cycle Assessment) method, and aimed at performing examination to contribute to advancement and the spread of the methods. In this study, we have invented LSA software to calculate environmental load of the whole lifestyle easily and developed it to make fit for practical use. We also applied LSA methods to an environment symbiotic apartment, to grasp their lifestyles and to propose how to improve them.

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As industrial techniques were upgraded and the quality of garbage began to change, disposal facilities had to become increasingly more complex systems. It became more difficult to maintain good design and operation. The number of accidents and other types of hazards were happening more frequently. The purpose of this study was to construct systems that will make disposal facilities safer by development method and system. We constructed ATHDB-all (Accident & trouble, HIYARIHATTO database) that have 3,262 cases and development the information collection tool by ICT (information communication technology). The purpose of my study is to construct ATHDB in waste disposal facilities by using ATHDB-all and the information collection tool. We introduce this tool to facility that manages office automation equipments etc. and collect 634 cases. Moreover, we analyze accident and trouble, HIYARIHATTO cases. In this facility, some accidents such as lumbago in convincing heavy object, broken bone by come in contact with forklifts, injured in taking pieces. It addition, improvements were also suggested for these accidents.

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A number of accidents are happening in waste disposal facilities. Diversity of waste and advancement of recycling system are considered one of the reasons. The purpose of our study is to develop effective safety educational tools for operators. To demonstrate in waste disposal system are the purpose, too. We developed APT (Accident Prevention Training tooD by 3D-VR (Virtual Reality) technology that supports safety education for operators effectively and efficiently. This paper has shown the advance of APT-SL. To introduce APT to individual facility, we added function. For example, APT-SL has the function to experience the accident or trouble and recovery them, to operate machines. Moreover, we examined the effectiveness of APT by examination. We produce the bulky garbage disposal facility that have 40t/Day disintegrator, and make the safety education program. The program was selected by analyzing the accident examples. And to try unitization of apparatus and equipments aimed at the simplification of 3D contents creation. The APT that introduce was appreciated in the facility.

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In this paper, we introduced "Environmental Contribution Points System", which was aimed at being able to grow Eco Users and reduce CO2 emissions. We made a CO2 database about the effect of reducing environmental load, taking advantage of Automobile Recycled Parts or proper maintenance. The load estimates CO2 quantification and it is used as "Eco Points" for users, who will purchase recycled parts or send their cars for maintenance. For example, in order to promote Environmental Contribution Points, we collaborated with Green Point Club, which had 12 organizations. It installed our database to show the amount of CO2 reduction and Eco Points each recycled auto parts.

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In this research, we have developed the BAS software as an effective evaluation tool for the municipal waste processing that the municipality and entrepreneurs used easily. First to think about what transportation of recyclable resources should be, we calculated costs and environmental impact of changing the route for the transport of waste in the island. Then based on the results, we calculated the effect when the method of processing and transportation are changed.

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Waste disposal and recycling facilities are criticized by nearby residents and many in various stages. The comments were composed images such as environmental damage to local environment due to operate facilities. The purpose of our study was to upgrade HPMAX aimed at introducing to domestic waste disposal facilities. That is the WEB site consisted by clear disclosure of the contents of general waste disposal facilities and investigation to nearby residents. Furthermore, as the sophistication of HPMAX development, improve the ease of finding information and the ease of updating.

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The bench-scale test of toluene removal is carried out using the surface discharge and an adsorbent with gas circulation. The liquid toluene is vaporized in the circulation line, and the toluene gas is adsorbed by the adsorbent. The hydrophobic zeolite pellet is used as an adsorbent. After the toluene adsorption, ozone caused by surface discharge is supplied to the adsorbent and adsorbed toluene is decomposed. Because the gas is circulated during toluene decomposition, ozone is used to decompose toluene effectively without waste. As a result, most of toluene is converted to COx successfully. The amount of CO_2 generation is larger than that of CO.

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The pilot-scale NO_x removal from boiler emission of city gas and heavy oil fuels was performed using indirect plasma and a chemical hybrid process. The flue gas flow rate was in the range of 455〜1,440 Nm^3/h, and NO_x concentration of 40 ppm in city gas firing and 96 ppm in heavy oil firing. The relation between NO_x removal efficiency and packing material height was investigated in order to reduce Na_2SO_3 consumption rate, varying the height from 2.1 m to 0 m. The packing height was 0.75 m enough to achieve 70% of NO_x removal efficiency for city gas, and 60% of NO_x removal efficiency for heavy oil.

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Recently, the authors realized a new prototype of plasma-assisted environmental protection aftertreatment system using atmospheric-pressure nonthermal plasma combine processes for super clean diesel engines. This systems do not use any rare or precious metal catalysts and harmful ammonia or urea solution, and now at the stage of pilot-scale plants tests supported as a national supported program. In this report, recent status of the achievement is reviewed. The developed system demonstrates excellent energy efficiencies to meet the most recent Japanese national regulation of diesel engine exhaust gas.

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An ammonia radical injection DeNOx system using an intermittent dielectric barrier discharge (DBD) with a one-cycle sinusoidal-wave power source has been developed to reduce NOx from incinerators. When DBD plasma-generated radicals (NH_2, NH, N and H) are injected into a flue gas containing NOx, NOx is removed efficiently by chain reaction in gas phase. Energy efficiency of DeNOx in this system is 120 g-NO/kWh, which is the higher efficiency than other DeNOx systems using different plasma techniques. However, we have not been explained detailed reaction mechanism yet. In this study, emission spectrum of NH radical was investigated by emission spectroscope. Maximum emission spectrum of NH radical was obtained at an applied voltage of 12 kV for a NOx reduction agent flow rale of 15 L/min and a NH_3 concentration of 500 ppm.

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Research on operationg conditions of fabric filters to minimize an emission of unintentionally produced POPs from aluminum alloy smelting plants was conducted. A small experimental fabric filter installed in a tentative flue gas line from a recycled aluminum smelting furnace was used instead of the actual operating filter. The results shows that more than 90 % removal efficiency of dioxins by using the fabric filter requires as low as 75C of the temperature of filter surface for the aluminum smelting plants. It means dioxin formation in the fabric filter could not be ignored below 100 C although it is known to be negligible less than 200 C in the case of waste incinerators flue gas. Injection of NaOH solution in an upper stream of the filter is quite effective for dioxin reduction and not so far for PCBs and HCBz. However, injection of activated carbon is effective enough in reduction of PCBs and HCB and not so far of dioxins. The reason of same operation exerts different effects on reduction of PCBs and HCB by fabric filters from dioxins, is attributed to the difference of their formation mechanisms.

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There is problem for health and the environment by chronic exposure of volatile organic compounds (VOCs). Non-thermal plasma technology offers a reformative approach to the problem of removing various VOCs. In this study, VOC decomposition using honeycomb type discharge reactor has been experimentally investigated. Discharge plasma was occurred at end face of zeolite honeycomb. Humidity of the feed gas was considered discharge parameter on zeolite honeycomb. Discharge emission was observed, adsorption and desorption of VOC on zeolite honeycomb were investigated. A toluene, which is one of the most commonly used VOCs, was used and the decomposition characteristics by discharge plasma were investigated.

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The removal of hydrogen in off-gas from fuel cells is desired to be safely processed. In the present research, simulated molecular hydrogen gas mixed with oxygen and nitrogen gases was directly removed in an intermitt ent dielectric barrier discharge (DBD). Hydrogen was oxidized even in a temperature lower than 100℃. A hydrogen conversion rate of approximately 100% (98.8%) was obtained at a consumes power of 1.2kW for a gas temperature of 80℃. When oxygen concentration was increased, NO was obtained as a by-products. But NO was reduction by increase of equivalence ratio. Their reaction mechanism was investigated at simulation with elementary reactions of H/O systems.

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Fundamental characteristics of N_2O decomposition by atmospheric non-equilibrium plasma were investigated to reduce greenhouse effects under an atmospheric temperature without catalysts. A pulsed dielectric barrier discharge (DBD) with a one-cycle sinusoidal-wave power source was employed. Plasma conditions (applied voltages and its repetition rates), gas composition, and gas flow rate were varied. In N_2O-O_2-Ar system, an N_2O concentration of 30 ppm was completely decomposed by DBD at O_2 = 0%, but the rate of N_2O decomposition was decreased with increasing O_2 concentration. The energy efficiency was 0.5 g-N_2O/kWh. Unfortunately, in N_2O-O_2-N_2 system : N_2O in actual flue gas was not decomposed by DBD under excess O_2. Formation and decomposition mechanisms of N_2O were experimentally discussed. N_2O formation, N_2 + O → N_2O, is a dominant reaction below O_2 = 5% in nitrogen rich gas.

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A steam plasma flow generated by a dielectric barrier discharge (DBD) at atmospheric pressure was developed to understand the generation mechanism of OH radical and its sterilization efficacy. It was clarified that the OH radical is the important factor for sterilization since the steam plasma had a sterilization effect at the discharge region, although H_2O_2 in condensed water did not have sterilization effect. The OH radical was generated from the wire electrode toward the ground electrode and the concentration of H_2O_2 increased after streamer propagation.

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An effective decomposition method for perfluorocarbon-14 (PFC14 ; CF_4) which is known as a global warming substance, has been developed. Successfully, this method decomposed PFC14 under dry conditions using a solid alkali and γ-alumina, and any liquid waste treatment was not required for outlet gas treatment as an expecting feature. We found that fluorocarbon-14 was decomposed quite enough, and the experimental result could be satisfied with the national criterion. The decomposition temperature was lower than that with the typical combustion system applied for almost all perfluorocarbons except for PFC14.

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Gasoline vapor emissions in gas stations are regulated by the revised air pollution control law. Tatsuno Corporation and Mitsubishi Electric Corporation have developed a gasoline recovery technology and unit which intakes and liquefies the gasoline vapor leaked from the car fuel tanks while refueling. It has been confirmed that our targeted values: exhaust concentration below 2 vol% and gasoline vapor recovery rate exceeding 90 %, are achieved by compression, cooling and adsorption processes. The field test machine stably worked for one year with an average recover rate of 0.1 % or more. The sales of gasoline vapor recovery unit for the petrol dispensing pump are scheduled to begin in fiscal year 2009.

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Rice husk activated carbon (RHAC) and coconut shell activated carbon (CSAC) were tested to remove sulfur compounds of benzothiophene (BT) types and dibenzothiophene (DBT) types from commercial kerosene. The adsorption isotherms of RHAC and CSAC for those sulfur compounds were obtained in batch-mode. Fixed-bed flowing tests were also conducted, providing their breakthrough curves of BT types and DBT types. It was shown that RHAC was effective to remove BT types, while CSAC was good at removing DBT types. The porosity and surface chemistry of RHAC and CSAC were studied in relation to their adsorptive removal performances of BT types and DBT types.

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The paper shows a several kinds of present aspects on global warming and the possibility of its prevention by the improvement of fossil fuel combustion. Although the application of electro-magnetic combustion technique makes it possible to attain at the most three percents of energy saving rate, it is possible to realize the Kyoto protocol by taking the electro-magnetic combustion technique together with the development of high efficiency heat transfer mechanism using the electro-magnetic technique depending on CO_2spectrum.

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In this paper, an experimental study of the baroclinic torque and buoyancy effect in a boundary region between the ambient air and burnt gas of a two-dimensional premixed laminar flame is made by shadowgraph method, laser tomography and PIV (Particle Image Velocimetry). It is found that vorticity is generated only on a boundary region in a dual-density non-reaction flow field.

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In this paper, a numerical study of the baroclinic torque and buoyancy effect in a boundary region between the ambient air and burnt gas of a two-dimensional premixed laminar flame is made by numerical analysis using the discrete vortex method. In this numerical analysis, a boundary region in a dual-density is replaced by a vortices, and the baroclinic torque and buoyancy is generated in a boundary region. In this report, flow configurations of the burnt gas is simulated by the numerical analysis method.

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A diffusive sampling device (DSD) has been developed for collection of μgm^<-3> levels of hydrogen sulf ide in ambient air. It consists of porous particles coated with zinc acetate as a absorbent, a porous sintered polyethylene tube which act as a diffusive membrane, and a small polypropylene syringe which is used for the elution of the analytes from the absorbent. The reaction of hydrogen sulfide with zinc acetate forms zinc sulfide, which can be converted to methylene blue through the reaction with N, N' -dimethyl-p-phenylenediamine. The concentration of methylene blue is measured by the use of an absorption spectrophotometer. Because of high sensitivity, the DSD has great potential in the evaluation of atmospheric environment.

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A membrane fouling using computational fluid mechanics was developed for the prediction of trans-membrane pressure increase during the operation and for the simulation of the influence of design and operational parameters, such as configuration of reactors, the position of membrane modules, permeate flux and air flow rate for aeration, on the performance of reactors. CFD was employed for the calculation of shear stress and the comparison of the calculated values with measured ones suggested the validity of CFD for the development of fouling model of MBRs.

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Ultra-high pressure underwater shock wave was applied to sterilize microbe. The imploding detonation of a propane-oxygen mixture was used to generate underwater shock wave in a steel pipe. We investigated imploding detonation waves in an approximately cone-shaped combustion chamber having a maximum inner diameter of 60 mm. As an object of the sterilization experiments, daphnias were used. The experimental results show that maximum pressure at the implosion center was 250 to 400 times higher than the initial pressure, and maximum pressure in the sterilization pipe was 48 to 60 % of the maximum pressure at the implosion center. We found that we could completely sterilize the daphnias by four times treatments of the underwater shock wave that maximum pressure was about 100 MPa.

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A series of numerical simulation was executed to investigate the photochemical Ox pollution in Osaka area. When the surface albedo of the urban area is increased to mitigate the mid-summer thermal environment, temperature decrease weaken the sea breeze, and it may cause the increase of the Ox concentration level. Sensitivity test about NOx and NMVOC reduction on the daily maximum Ox concentration shows that the most of the city area is NMVOC-limited. In some areas, reduction of solely NMVOC is more effective than both reduction of NOx and NMVOC.

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This paper focuses on starting-delay when vehicle starts accelerating when signal phase turns to green at a signalized intersection. How the reduction of starting-delay affects traffic throughout and emission was discussed. The authors proposed three different approaches to reduce the starting-delay such as (a) increasing sensitivity factor "a" of car-following model, (b) decreasing reaction time "T" and (c) both increasing "a" and decreasing "T". Traffic simulation was done for each starting-delay measure with different heavy vehicle penetration ; 0, 10 and 20%. Here, in this paper, traffic throughout was defined as the clearance time duration when the total traffic demand completely left the intersection. Also, emission is represented by CO_2 only. Numerical analysis significantly showed that reduction of reaction time effectively decreased CO_2 clearance time.

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The performance of large-eddy simulation (LES) for gas dispersion in an urban district is investigated. The present simulation is based on a finite volume method with an unstructured grid system to resolve flow structure in a complex geometry. To evaluate the performance of the LES, the results from the LES are compared with those obtained by the wind tunnel experiments, which were conducted for gas dispersion from a point source at the roof of a tall building in a complex urban district. The result shows that the LES can accurately represent the flow and concentration field provided that suitable numerical schemes are used.

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