In order to produce biodegradable plastics (poly lactic acid) from garbage, it is necessary to store garbage for some days in the system of garbage collection and transport through disposers and pipes. The effects of various factors (such as temperature, pH and aerobic / anaerobic storage) on the preservation and deodorization of garbage were investigated. The results of our investigation showed that the growth of putrefactive bacteria was inhibited, because the lactic acid fermentation during the storage led to a drop in garbage pH. It was proved that the optimum condition of storage was anaerobic storage at 5℃ with initial pH 3.43.

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In recent years, air pollution and depletion of oil resources become major issues all over the world. So environmental products and environmentally sensitive technologies are required. And fingers are pointing at importance of long-term using products for the construction of cycloid type society about resources is requested. Therefore this study proposes the concept of the product up-grading by exchanging main components. Applying this manufacturing concept, long-term use and the early intake of the new technology will be possible. In this study, we adopted the aotumobile as an example of the product up-gradig and actually converted internal-combustion engine vehicle to electric vehicle (EV). And we tested its performance. In addition, we attempted to make certain of effect by bringing in the prduct up-grading. Then we got the design guide aiming at conversion.

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In these years, increase of wastes and exhaust of resource become major issues according to raising the level of living. So management of wastes, especially material or part recycling from used products is one of the key factors solving these problems. In this point of view the disassembly-oriented design (DOD) for new products is one of important heads. In this study, we attempted to investigate DOD for TV and PC monitor by disassembling them. In addition, we investigated DOD for TV that is surpposed to release. And we compared the disassembling property of TV and that of PC monitor by applying the method of estimate products disassembling property. Then we got the guide about DOD for TV.

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In resent years, consumption of resource causes some environmental problems and it is demanded to consider a countermeasure for these problems, especially disposal and recycling of waste. Therefore, constructing the sustainable society with the inverse manufacturing process, which contains recycling and reduction of waste is needed. In recycling system, it can reduce the load for environment to carry out the process in short circuit. From this point of view, we proposed an Eco-Production System (EPS) which organized from Refurbishing, Reconditioning and Remanufacturing. This paper says about the structuring of EPS and giving an example to apply a General Durable Product to this. As a result, one new analysis methodology is established to Recycle systems. And this methodology becomes an indicator for design of products.

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The various kind of the new refuse disposal technology are developed and proposed. In this study, we estimated the life cycle energy and emissions for the new refuse disposal technology. And we investigated the power generation by waste heat and the new refuse disposal technology. For the Life Cycle Assessment (LCA) study, we studied the power generation by waste heat and various new refuse disposal technology using LCA methods (Environmental Load Point). And we compared with the power generation by waste heat of environmental load and the various combination of the power generation by waste heat and new refuse disposal technology of environmental load. The combination of the power generation by waste heat and new refuse disposal technology indicate low environmental load in this method.

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Various kinds of municipal solid waste (MSW) incinerators are developed in consideration of environmental load reduction and Kawasaki Heavy Industries, Ltd. (KHI) has many experiences of MSW incineration systems of different flue gas and ash treatment. This paper describes the relative inventory/impact comparisons and their contribution analyses of KHI's main 5 systems at the stage of operation by using the Life Cycle Assessment (LCA) method based on the detail input/output data. The environmental loads at the stage of construction of one system has also been calculated and compared with the loads at operation. The results show the effects on environmental load reduction by electric power generation and useful suggestions for further environmentally friendly system development.

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Gasification and melting processes for municipal solid waste (MSW) now attract much attention, because this type of processes can offer high efficiency in reducing polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) along with thermal efficiency. However dioxinxs formation may occur in de novo synthesis at around 300 ℃ in the post-combustion zone. Then, in this research, experiments were carrid out with a fixed bed reactor in order to elucidate the formation mechanism of dioxins from gasification-melting ashes. It was proven that the unberned carbon in gasification-melting ash was the primary source for dioxins in this system.

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To reduce PCDDs/Fs in the flue gas of incinerators, a kind of catalytic oxidation process has recently been recognized as one of the most effective decomposition methods. In this study, the decomposition behavior of Co-PCBs is investigated by comparing PCDDs/Fs in flue gas and using substitutive materials under dry/humid atmosphere. The decomposition mechanism of Co-PCBs is also investigated with the substitute. It is concluded that 1) Co-PCBs can be decomposed the same as PCDDs/Fs with the catalytic oxidation process even under the humid atomosphere of flue gas, 2) bi-phenyl (BP) is more suitable for the substitutes of Co-PCBs than Chlorobenzenes among no oxygen aromatic model-compounds and 3) the main reaction in the decomposition scheme of BP can be estimated to be on irreversible complete destruction of the aromatic nucleus.

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Adsorption characteristics of activated coke and carbon adsorbents were investigated by using a flow-through type test equipment and a surrogate adsorbate of 1,2,3,4-tetrachlorobenzene (TCB) that may be a precursor of dioxins formation. Break through curves were measured in this equipment. Emphases were placed on the amounts of adsorption and the effects of temperature, moisture content of gas and the kind of adsorbents on the amounts. The adsorbed amounts in two activated coke samples were 1.7-5.8 mg-TCB/g, whereas 4.6-26 mg-TCB/g in an activated carbon. The amount in activated carbon was about 2-5 times of that of activated cokes, which might be reflecting the nature of cumulative micro-pore volume of the adsorbents. The adsorbed amount decreased with an increase in temperature, whereas it was not influenced by moisture content in flue gas.

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We are under development of collecting the fly ash under high-temperature flue gas condition. The experiment was performed mainly to check for the dust collection efficiency under high-temperature condition as well as for clogged filter under continuous operation condition. Results obtained through the experiment are as follows; 1) The pressure loss of filter was changed within the range of 1.37kPa∿1.72kPa during the operation of one week, which assured the stabilized operation. 2) The concentration of dust at the outlet of Hot Gas Filter was 0.042/m^3_N, and the dust collection efficiency was approx. 99.5%. 3) The concentration of dioxins contained in the ash collected by the Hot Gas filter was 0.0004ng-TEQ/g. The concentration of dioxins at the outlet of Hot Gas Filter was observed to be decreased down to 0.064ng-TEQ/m^3_N, whereas that at its inlet was 0.24ng-TEQ/m^3_N, which made it possible to confirm that the dioxins would be dissolved by passing them through the Hot Gas Filter.

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Mercury and dioxins are contained in the sludge of waste water from a wet scrubber in a municipal solid waste incineration plant. The study of the treatment method of the sludge is becoming an important technological subject. In this study, mercury in the sludge is found to be vaporized at around 200℃, at which temperature the vapor pressure of dioxins are very low. This means that mercury vaporizes from the sludge and the dioxins remain in the sludge at that temperature. The dioxins remained in the sludge can be decomposed at a higher temperature by feeding the sludge in a furnace. As the result of this study, a two-stage heating process which can safely treat the sludge containing both mercury and dioxins is proposed.

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This paper describes emissions and the dependence on particle size of trace elements, which are Hg, Cr, Ni, Mn, Cu, As, Se, Cd, Sb and Pb, in flue gas from MSW incineration (MSWI). We measured them at five MSWI plants which applied dry type of flue gas treatment included bag filter to reduce dioxins. And we got following results; (i) Cu, As, Se, Cd and Sb had a trend to be condensed under 1 micro meter. Mn was condensed under 1 micro meter and over 10 micro meter. Cr and Ni showed different trend in each plants. (ii) Dry type of flue gas treatment is good enough to remove trace elements and meets German regulations.

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Recently, environmental pollution caused by emission of toxic substances from waste incineration flue gas has been become a social problem. For removal of toxic substances as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, Bag filter systems are used in many cases. This system, however, needs waste gas quenching apparatus to remove toxic substances efficiently and for its protection. So far, two-fluid nozzle was used for quenching [cooling] frequently and it needs compressor to atomize water. We developed air assisted pressure nozzle as energy saving two-fluid nozzle for waste gas quenching [cooling]. This nozzle can atomize water in low power compared with two-fluid nozzle. In this paper, we report the characteristics of air assisted pressure nozzle and installation case in actual waste incinerator plant.

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A new and novel concept of exhaust energy recovery from furnaces is proposed herein, by use of a turbomachine working as an inverted Brayton cycle. The main feature is that simultaneous generation of electricity and hot water in rather simple configuration. Boilers and steam-turbines are no longer required.

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This is an operational review of Kougasaki Combined Power Generation Facility with MSW Incineration that was completed in July of 1998 at Kitakyushu City. The power generating facility of this plant was designed to meet the maximum quantity and maximum calorific value of the waste to be treated, and is one of the largest of such plant in the country. Currently, however, it is restricted to run at nearly the half-load level. The report explains the method of power generation control that matches the fluctuation of the load, and also presents the economic advantages and reduction of environmental burden by the use of combined power generation system.

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Corrosion test was conducted at a municipal refuse incinerator using four kinds of super heater tube materials including the materials developed by us for high-efficieny electric generation at the temperature of 400 to 450℃ for two years. The results showed that two kinds of QSX materials developed were equal to or more corrosion resisting than the present materials for superheated steam of high temperature. The guideline of boiler design concerning exhaust gas and steam temperature was indicated using stainless steal of SUS310 class to depress the maximum thickness loss of 0.6mm/year. The QSX-alloy indicated uniform metal wastage after slight pitting while SUS310 and HR11 indicated local corrosion form of pitting and intergranular corrosion. Corrosion mechanism is considered to be the complex corrosion of gasification corrosion and melt salt corrosion which is effected by adhered ash components and exhaust gas temperature.

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We developed a predictive steam flow rate control system using generalized radial basis function, focusing on chaotic motion of steam flow rate of refuse incinerator. Predicted signal has optimized with online learning and predicted time has optimized with real time prediction of reliability of predicted value using Lyapunov exponent. This system is characterized by tuningless and good performance of reliability of predicted value. This system has been installed and tested at an incineration plant with industrial scale and showed good control performance compared with a conventional control system.

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Direct numerical simulations (DNS) of propane-air turbulent premixed flames propagating in two-dimensional homogeneous isotropic turbulence are conducted to clarify the structure of turbulent premixed flames. Detailed kinetic mechanism including 325 elementary reactions and 53 reactive species are used to simulate propane-air flames in turbulence. Local heat release rates are well correlated with curvatures of the flame front. Flames convex toward the burnt gas show large heat release rate, while those concave toward the burnt gas show relatively low heat release rate. C_3H_8 consumption rate is also well correlated with curvatures of the flame front. Flame elements with large curvature show large C_3H_8 consumption rate. Flame elements compressed by turbulence possess large NO production rate, while stretched flames possess relatively small production rate.

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Recently, the exhaust gas from motorcar causes serious air pollution. Specially, nitrogen oxides not only leads to environmental problems but also causes health problems. So it is demanded to consider a countermeasure for this problem. Therefore, in order to purification the air near the road, nitrogen oxides removal system is proposed. This paper says about the prediction of absorption mechanism and its controlling rate, using a motionless gas-liquid mixer so as to make micro bubbles of sampling gas. As a result, 1) As for nitrogen dioxide absorption into water, this reaction mechanism is controlled by chemical reaction. 2) As for nitric oxide absorption into water, this reaction mechanism changes chemical reaction control region to physical desorption control region for NO ratio.

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In order to make explanation of NOx absorption mechanism into water, we assume the numerical simulation model. This model based upon chemical reactions in aqueous solution is calculated numerically by applying the Runge-Kutta method. The calculated results agree with the experimental values on both static and dynamic characteristics. And the absorption-controlling rate can be obtained by using the characteristic time. The result of analysis is as follows; 1) NO_2 absorption is under chemical reaction control. As for NO, however, it is changed from chemical to physical desorption control as NO/NO_x increases. 2) The reaction path is changed by NO/NO_x. Especially if NO/NO_x equals 100%, oxidation of NO with dissolved oxygen becomes the rate-determining step. 3) The absorption characteristics does not depend on NO_x ion concentration. Under acid conditions the removal efficiency decreases as acidity increases.

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Absorption rate of nitrogen dioxide (NO_2) at water surface was experimentally determined. Total concentration of nitrous (HNO_2) and nitric acid (HNO_3) was directly proportional to NO_2 concentration. It also depended on the water temperature and followed Arrhenius' law. The existence of NO did not have much influence on NO_2 absorption rate. Experiments of NO_x absorption at condensing heat exchanger were carried out. In this case, the concentration of NO^-_x(NO^-_2+NO^-_3) decreased as the condensation rate increased. It was shown that the amount of NO_x dissolved in condensate on heat exchanger increased as NO_2 concentration and condensation rate increased and was well correlated with the amount of NO_2 gas passing through heat exchanger.

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In order to reduce the concentration the diesel soot particles PM and NO_x in the diesel exhaust, exhaust gas is excited by passed though a corona discharge collector for diesel soot particles (CCDS) and a corona discharge reactor for NO_x (CRNR) in the high electric voltage field. In a CCDS, diesel soot particles is accumulated on the central electrode, after that, soot particles is removed by the incineration technique. In a CRNR, NO_x decreases as is oxidized to HNO_3. In this study, we coupled these corona reactors for removing the soot and NO_x, and we tried driving test on road using a diesel-engine truck equipped with the presented apparatus. We found that 1) the soot removal rate of 60% obtained at a corona input power of over 40W, 2) the NO_x removal rate of 97% obtained at a corona input power of over 100W, and 3) Soot removal rate was influenced by water contained in the exhaust gas.

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Nitrous oxide (N_2O) in the atmosphere contributes to the greenhouse effect more significantly than CO_2 gas. In addition, the ozone layer is possibly destroyed by NO produced from N_2O as well as chlorofuloro carbons (CFCs). In spite of world-widely understanding of the increase ratio to concentration of N_2,the origin emission sources are not clarified, which caused recent drastically increase in atmospheric concentration. One of the N_2O emission source is widely used as anesthetic in the operating rooms of hospitals. Since even minute concentrations of N_2O may cause health problems for operating-theater staff who are chronically exposed, the exhaled air from the patient as well as any excess N_2O should be exhausted from the area without their exposure. In this study, the degree of conversion of N_2O to N_2 and O_2 was investigated experimentally with Rh/Al_2O_3 and Pd/Al_2O_3 catalysts, and the optimum conditions of operation were determined.

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Ab initio molecular orbital calculations were performed to derive rate expressions for the reactions of N_2O with O(3^P) and CO. Major products of O(3^P) + N_2O reactions are predicted to be NO + NO rather than N_2 + O_2. Comparisons of calculated and experimental rate constants indicate good agreement exists with the most recent experimental values.

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In order to prevent the depletion of the ozone layer due to CFCs, we have experimentally evaluate applying the DC corona discharge reactors to a gas contained CFC12. Mixing gas of Air (0.4l/min) and CFC12 (20000ppm, 0.043g/min) is excited by passing though a corona reactor in a high electric voltage field. Maximum input power of this experiment is about 190W. Exhaust gas from corona reactor was introduced to the treatment vessel in which H_2O and Ca(OH)_2 have fulfilled in order to control of by-products. And temperature of inner surface of reactor increased about 110℃ for 60 minutes. Therefor, reactor was cooled by water. In this experiment, corona discharge condition was observed by the infrared thermograph, and CFC12 decomposition rate was measured using gas chromatograph (GC). We found that 1) CFC12 decomposition rate of 99% obtained at an input power of about 190W. However, decomposition rate decreased from 99 to 30% after 40 minutes, 2) CFC12 decomposition rate of about 10% increased by the reactor cooling. 3) by-products in the exhaust gas weren't detected by the GC and detection tube, while the C1 and F ions were detected 75ppm and 50ppm, respectively.

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"World Econo Move" is the event competing for the driving distance with the battery in an equal condition. We designed and manufactured new Econo Move car with the aim of the low air resistance. And we tested performance of new model. From the data, drag coefficient and coefficient of rolling resistance were calculated. Comparing new model with 1998 model, it was clear that watt consumption of new model is 9 percent less than that of 1998.

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The paper reports on the development of a condensing water heater with a thermal efficiency of 95 percent (based on the net calorific value at maximum rated output) and thermal output of 35 kilowatts. The thermal efficiency of conventional instantaneous water heaters is around 80%. Fitting a highly durable latent heat exchanger to recover even the latent heat in the steam in the exhaust gas gives the unit a thermal efficiency of 95%, a world best for an instantaneous water heater. The unit is equipped with a full primary combustion ceramic burner, reducing emissions of NO_x (crucial to global environmental protection) to 30ppm, half the level of emissions of current low NO_x water heaters. The heater was injected into the market in October 1999.

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The diffuser of a membrane module for use in water purification was studied and the design specifications of a diffusing trough that has diffusion slits on the sides were obtained. A test-fabricated multi-element large-capacity membrane module that incorporates a diffusing trough was run continuously in a pilot plant. The treated water satisfied the water quality standards, the interval for chemical cleaning was two months or more, and the recovery rate was 95% or more, confirming the processing performance. A large-capacity membrane unit that is capable of application in medium-scale purification plants that treat several thousands of cubic meters of water per day was test fabricated with multiple large-capacity membrane modules. Studies of stability in operation under a high-turbidity load of 60-80 degree turbidity confirmed stable operation over a 25 day period with a treated water turbidity of 0.01 or less and a trans membrane pressure differential of 40kPa.

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On advanced drinking water treatment, including unit processes of ozonation, ozone resistant membrane filtration and granular activated carbon (GAC) tower treatment, pollutant removal performances of unit processes and relationships between some operational conditions and membrane filtration flux were examined. From the experimental results, it became obvious that it was necessary to maintain residual ozone concentration of 0.2 to 1.0mg/L in the filtrate from the membrane module in order to maintain higher membrane filtration flux. With ozone dosage of 3mg/L by an ejector and with operation mode of dead-end filtration, membrane filtration flux of more than 5m^3/M^2/day could be maintained. Quality of the effluent from GAC tower constantly satisfied Japanese standard for drinking water.

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It has been known that ultrasonically induced cavitation is effective for sterilization of liquids contaminated by microorganisms. We have devised a system to induce cavitation utilizing the squeeze film effects and fabricated a prototype sterilizer with the system. In the sterilizer, sterilization is performed in an area formed by a cylindrical shell and two short columns vibrating at the fundamental coupling vibrational mode in the axial and radial directions. We evaluated the sterillizer by using water contaminated with E. coli in a flow system and obtained very promising results. We found that sterilization could be achieved more efficiently and steadily than a conventional ultrasonic sterilizer which uses a standing wave field. The steadiness is a very important factor in ultrasonic sterilization.

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They are called the age of environmental problem and bioscience in the twenty-first century. In this study, aquatic environment utilizing various bacteria for mass generation of Genji firefly is realized, and the research on lifetime breeding of the firefly over the 11 generation is carried out by the present. This lifetime breeding is a very difficult problem, when the appropriate aquatic environment is not achieved, and here, various trials will be given for the achievement of the aquatic environment. The environments, which are optimum for the firefly, also seem to be necessary for the human life.

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This report is related to the septic tank which a Bacillus bacteria and a iron bacteria were used for. The iron bacteria is made to propagate by conducting the thermal insulation to home scale septic tank and putting iron scraps into the anaerobic region, further water purification is carried out. COD[ppm] is used for the index of the water quality processing effect, and the desired value is made to be 10[ppm] or less. The conclusion were as follows : 1) The COD value of the first septic tank in putting the garbage is 2000∿5000[ppm]. In addition, COD of the second tank exit was kept to 20[ppm] or less in the case. 2) It is based that COD decreases with the temperature rise on the work of fungus which makes the walnut charcoal to be house and iron bacteria.

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This report concerns thermal management in the high grade septic tank. The insulation of the home scale combination septic tank is done. Iron scraps is put, and water purification is carried out using iron bacteria. The temperature in the septic tank must be kept at about 20℃∿30℃ in order to activate the activity of iron bacteria this time. The heater is installed in the purifying chamber in the reason. Heat exchange of entrance and exit is carried out by the heat exchanger in order to raise the efficiency. It tried to make energy balance figure of the whole system.

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Membrane separation activated slug using flat plate membrane has become popular waste water treatment process. The most serious problem of the process is cloging of membrane. Air scrubing is employed to prevent it. Mechanism of air scrubing is shear stress on the surface of membrane created by rising of air bubbles. By observing behavior of air bubbles and by measurement of the shear stress. the mechanism of sustaining operations was analysed.

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Recently, wasted water treatment technology by using freeze concentration is noted by its low running cost. In this study, 10 vol% ethylene-glycol aqueous solution was utilized as a testing solution to investigate the parameters that effect the concentration and the dilution. It was found that diluted solution with lower concentration is obtained by keeping the temperature difference between brine and freezing point small. It was also found that the stirring prevents ice from adhering to the cooling wall and the form of container for separation improves the efficiency of separation.

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The decomosition of sludge brings not only the decrease in the sedimentation and the recovery of solid material at gravity thickener, but also the decrease in the efficiency throughout the process of further treatment. With our recognition of the significance in the prevention system of decomosition, we have found that vacuous process of sludge prevents its decomposition, and we have confirmed its practicability in the actual device, in addition, the device can be successfully simplified. The efficiency of this device, especially in the primary sludge and exess sludge, and appropriate example at a small scale sewage treatment plant have been reported in this article.

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In this paper, an evaluation scheme "ESS (Eco-Load Standardization Scheme)" that uses common standard unit to evaluate any global environmental issues and to define the relation between human action and global environmental issues is proposed. In this scheme, global and regional environmental issues are evaluated numerically and totally with NETS (Numerical Environmental Total Standard), especially a waste processing and recycle stages are introduced in this paper. A LCA software includes ESS is built up and the industrial products are evaluated with the software. The transition of a eco-load with the change of the generation of a industrial products is estimated as a case study. So, the LCA scheme ESS and the ESS software are found to be useful for Eco-product design.

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Life Cycle Assessment (LCA) has been greatly paid attention of its effectiveness in evaluating environmental impacts through the lifecycle of any industrial products. In this paper we are focusing the evaluation of metal processing such as cutting, welding, painting etc. during manufacturing process. The ESS-LCA method is used to analyze the environmental load of the process. As a result, the inventory data system of the metal processing has developed and, a list of estimations using NETS values as points of reference for further development and refinement to much more environmental friendly manufacturing.

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The Life Cycle Assessment (LCA) is the method which quantitatively evaluates the environmental impacts along life cycle of products or services. Various kinds of methodologies and procedures for LCA have proposed by the research groups in Europe and the USA. However, they are not only tentative, but also unacceptable worldwide. Using the panel method, we have gathered information about category weighting factors and proposed Environmental Load Point (ELP) as a single indicator. In this report, firstly we evaluate the environmental impacts of air-conditioner including HCFC, R-410a, and refrigerator including HFC, HCFC with ELP. Secondly, we evaluate the environmental impacts of air-conditioner and refrigerator at Demonstration Plant for Recycling Post-use Electric Home Appliance. The results show; 1) Metal Recycling is effective to reduce the environmental load of Electric Home Appliance. 2) Reduction rate of environmental load of air-conditioner is highest at Recycling Plant.

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In order to develop a 9.8MPa/500℃ highly efficient waste-to-energy plant with 30% electric efficiency, application of highly corrosion resistant materials for superheater and corrosion resistant coatings for waterwall are indispensable. The corrosion lives of six conventional and five newly developed superheater tube materials and three coatings were demonstrated for two years in the NEDO waste-to-energy pilot plant. As the results of the demonstration test, an excellent durability of more than 10 years for Ni-Cr-Mo alloys of 3rd superheater and for Ni-Cr-Fe alloys of 2nd superheater were clarified. Also, corrosion resistant coatings of alloy 625 weld overlay and NiCrSiB alloy HVOF spraying applied on waterwall showd a good durability. From the results mentioned above, technical reliability of a 9.8MPa/500℃ waste-to-energy boiler having long durability were demonstrated.

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Power plants inventory database has developed to support a deterministic quantitative model to compare the technical-economical and environmental features of various electric power plants. A customized computer code is developed to evaluate the overall function of alternative energy systems. The ESS-LCA method is used to analyze the environmental load of each power generation system in the lifecycle. The final result will be a rank of alternative sources of energy based on the composite distance of each alternative to the designated ideal source of energy.

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This paper shows the environmental load evaluation of a co-generation system with the aid of "ESS (Eco-load Standardization Scheme)" proposed by the authors. This scheme is applied to co-generation systems with different types of conditions. Further more, this evaluation includes some environmental issues, they are not only fossil fuels depletion and global warming due to CO2 emission but also rain acidification, natural resource depletion and so on. In thins evaluation, three kinds of fossil fuels are considered as a fuel in the evaluation of a co-generation system, comparing and analyzing about three fuels. We propose here the software "ESS (Eco-Load Standardization Scheme)" with cost analysis. A computer algorithm and software optimizing the environmental load and cost performance are accomplished by using a combined simplex and branch-bound technique. So, we can evaluate the environmental loads rapidly and easily with this software. As the results, an optimum eco-operation way for cogeneration system can be found.

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Japan has promised the reduction Green House Gases emissionex in COP3. The objectives of this research are as follows. 1. To exsamine the change of energy consumption and CO2 emission from iron and steel industry 2. To estimate the introduction possibility of the new technologies. 3. To forecast the future emission

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In this paper, a one-air-point model (macro model) was applied to long term simulations to investigate the thermal performances of PCM wallboard asuuming a winter season in a cold climate area in Japan. The convective heat transfer coefficient in the macro model was given using results of short term calculations with a CFD code (micro model). Macro model was able to predict the thermal environments in quantitatively acceptable accuracy compared with micro model and was also able to reduce CPU time drastically. Results with long term simulations showed that PCM wallboard is effective in the energy saving, in the cost saving, and particularly in the peak power reduction.

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Energy use and CO2 emission for heating and cooling system in a National Institute in Tsukuba, Ibaragi were analyzed. Comparisons of energy use, CO2 emission and operational cost for annual bases were also made for the present intensive heating and cooling system and an alternative system of personal air conditioning. The following results were obtained by the present analysis : 1) energy use of personal system was superior to the intensive system, 2) CO2 emission from the personal system was lower than that of the present intensive system using kerosene as the fuel, but, is nearly equal to the present system if the fuel is changed to natural gas, 3) the intensive system using kerosene and even using natural gas, the operational costs were estimated to be lower than that of the personal system.

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A model with which to estimate long-term average atmospheric concentrations of chemicals was developed. The model validation was conducted for trichloroethylene and tetrachloroethylene concentrations in atmosphere by comparing calculated values and observed values from a monitoring survey conducted over several weeks in summer and winter in the Kanto region. A good agreement with the measured values was obtained for the monthly average concentration of trichloroethylene, excluding two sites in the winter measurements where the monitored values were extremely high. For tetrachloroethylene, the calculated values greatly overestimated the monitored values at urban sites. The use of emission data with better accuracy will be able to improve the model performance, because the extremely high calculated value was mainly influenced by the methodology used to estimate the gridded source inventory. The model is capable of estimating the long-term (such as monthly) average concentration distribution of chemicals in a wide flat area such as the Kanto plain.

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We developed the numerical model to predict the micro climate change in a few km2 scale. The multinesting technique was used to take in the synoptic influence. We applied this model to the residence development area in Mino Osaka. The calculated temperature and wind in the present state were agreed with the observed data reasonably. So the accuracy of this model was verified by these results. Next, we examined the influence on temperature by changing the ratio of green coverage and building coverage, and albedo value of road in the residence development area. We could get the reasonable results qualitatively. In the future, it is necessary to verify quantitatively by compared with observed data.

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Heat island is produced by exhaust gas and decrease of green belt. But some other factor is possible like stored energy of solar. Solar energy heat the surface of construction materials. Surface temperature may be changed by it's roughness and color. This paper describes measured result of test piece by spectrometer. Then compared the difference of surface temperature.

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Desalination of seawater plays an important role in short water supply which is one of the global environmental problems. Solar desalination system is more desirable for global environment than that using fossil fuels. A conventional roof type solar still using newly transparent film instead of usual glass cover was studied by computer simulations using a numerical one-dimensional model in outdoor and indoor experiments. The experimental results showed that an increase in the wind speed on the roof brought an increase in difference of temperature between water and the film cover, resulting, an increase in the still yield.

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Urban environment in mega-cities like Tokyo is still getting worse and worse. For example, concentration of carbon dioxide (CO_2) and NO_2 is still increasing. Another serious environmental issue is "urban warming", which is caused by concentrated consumption of energy in the urban area. The cause of aggravation of the urban environment can be mainly attributed to increase of automobiles in this area. In the present study, we will report the energy flow and the waste heat of the future vehicles including electric, hybrid, and fuel cell vehicles. In addition, the new air conditioning system is designed to reduce the effect of the waste heat emission.

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