Recycle rate of automobile is 80%, and remaining 20% is disposed by landfill. Most items of remaining 20% are occupied with ASR, but since the landfill disposal place is insufficient, necessity of raising recycling rate is increasing. In order to solve this problem, field test of ASR recycle plant has been operated for two years or more. The feature of this system is combination of gasification by pyrolysis of ASR and reforming of pyrolysis gas. This system enables the conversion of ASR into fuel gas. Fuel gas that consists of hydrogen and carbon monoxide as the main inflammable components can be used as fuel for gas engine generators and heat source of pyrolysis kiln. This paper introduces gas engine operation characteristics, such as power efficiency and operation stability.

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In recent years, troubles of fire and burst at waste disposal processes have been rising. In this report, we investigated the cause of the large scale burst of Mie RDF power plant occurred in August last year. We especially focus attention to the final cooling process of RDF production line. We simulated the cooling and heat production characteristics of stored RDF. Then we obtained two conclusions. First, when RDF is piled up as a cube with side length of 3 meters in a pit silo, minimum ignition temperature is about 54 degrees. Second, it is important to keep the temperature under 40 degrees and to limit the height of piled up RDF under 5 meters at storage.

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This paper reports on the field test of the high-temperature corrosion monitoring sensor for boiler tubes in waste incinerators. The sensor, equipped with the electrode part for electrochemical measurement, were inserted in the boiler furnace in a municipal incineration plant and the parameters for the corrosion measurement were observed for 322 hours at 30-minute interval. The conditions for the measurement were as follows; material of working electrode: Alloy 625, gas temperature (T_<gas>): 560 to 650℃ (599℃ on average), metal temperature (T_<meial>): 510 to 560℃ (544℃ on average). In a set of measurement, the polarization resistance of Alloy 625 was evaluated by electrochemical impedance measurement first, and then the corrosion rate and the corrosion depth were calculated by simultaneous operation. The total corrosion depth observed with the corrosion sensor was 0.11 mm and this value was in error of only 0.06 mm against the accurate value obtained by measurement of the loss-of-size of the electrode with a micrometer. The observed data provides the contour map of the corrosion rate of Alloy 625 represented in the T_<metal>-T_<gas> coordinate system, useful for the corrosion protection and the material selection in waste incineration boilers.

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In recent years, the amount of excess sludge increases with the spread of sewage treatment equipment, and there need methods of reduction and recycling excess sludge. We developed hydrothermal pre-treatment that promotes anaerobic digestion of excess sludge. As a results of experiments .hydrothermal treatment and digestion, we make clear the best conditions to improve digestion, temperature 150-170℃, pressure 0.95MPa, and air supply of very small quantity. Furthermore, a result of trial calculation in case of applying to digestive process shows that hydrothermal pre-treatment reduce residue and produce electricity largely than usual, the reduction rate of sludge is above 40%, and the production rate of electricity is above 70%.

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Most of the sewage sludge generated in usual sewage disposal plants is burned at atmospheric pressure fluidized bed incinerators. In these plants, energy recovery by heat exchange of an exhaust gas and combustion air and defogging air is performed. From the viewpoint of global warming prevention, energy usage of exhaust gas is asked further. In this study, a new energy recovering system from sewage sludge is proposed. This system consists of a pressurized fluidized bed combustor (PFBC) and turbo machinery. The sewage sludge is incinerated in the PFBC and the pressurized high temperature exhaust gas drives a turbine directly. We compared 3 new systems combined of PFBC and turbo machinery with the existing system from a viewpoint of CO_2 emissions and power consumption.

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The purpose of this study is to establish a super power generation system where hydrogen rich synthesis gas, meeting the limit to the fuel of MCFC (Molten Carbonate Fuel Cell), can be efficiently extracted from biomass via the gasification and reforming technology. For that purpose, the experiments of architectural salvages gasification were performed with a bench scale two-step gasification system. The main influence factors on hydrogen production in the catalytic process and the non-catalytic process were investigated, and temperature was found to be the most important factor. At 950℃, without catalyst employment, the synthesis gas containing above 50% (% V/V) hydrogen was perfectly extracted from feedstock with the suitable selection for the operation parameter of S/C (Steam/Carbon Ratio) and ER (Equivalence Ratio). However, with employing commercial reforming catalyst to the reforming process, the similar result can be generated just at 750℃.

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We are now constructing woody biomass gasification power generating facility with the capacity of lOOt/d which is the first plant in Japan. And operation of this plant will start in December 2004. This system makes high-calorie pyrolysis gas from woody biomass which is difficult to recycle directly, using indirectly heated kiln type gasifier. The pyrolysis gas is used in generation of electricity and for other various purposes. And pyrolysis coke are used varied object like solid fuel and activated carbon. We continue to study to convert pyrolysis coke to gas fuel. This paper describes outline of energy recycling facility and result of basic studies for woody biomass gasification.

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Methanol gathers much attention as a fuel of fuel cell and a esterification material of bio-diesel oil. In order to obtain methanol sustainably it is very important to get methanol from wood-based biomass and the like, which can be synthesized from H_2 and CO generated by gasification of wood-based biomass. The better performance for the methanol synthesis requires optimum quantity ratio of H_2 and CO. Hence, the objective of this study is to investigate systematically behavior of synthesis gas composition influenced by physical conditions such as heating temperature and humidity of the test samples. The typical testing results related to this matter are reported here together with examination on H_2 generation from charcoal, namely, by-product of the gasification.

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A conceptual design of an energy recovering system from sewage sludge incineration is proposed. This system consists of a pressurized fluidized bed combustor, a turbo charger, and a heat exchanger for preheating of combustion air. Electricity consumption can be reduced by producing high pressure air which can be used as the aeration air in the sewage treatment process. In order to know the combustion characteristics of the sewage sludge under the elevated pressure condition, combustion tests of actual wet sewage sludge were carried out by using laboratory scale pressurized fluidized bed combustor. Combustibility of the sewage sludge was good enough and almost complete combustion was achieved in the combustion of the actual wet sludge. CO emission and NOx emission were marvelously low especially during the combustion of wet sewage sludge regardless of high volatile and nitrogen content of the sewage sludge. However, nitrous oxide (N_2O) emission was very high. Hence, almost all nitrogen oxides were emitted as the form of N_2O. From these combustion tests, we judged combustion of the sewage sludge with the pressurized fluidized bed combustor is suitable, and the conceptual design of the energy recovering system is available.

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A high-performance sewage sludge incinerator has been developed using a circulating fluidized bed. Demonstration testing clarified that (1) dried sludge and sediment added to sewage sludge are incinerated cleanly, and that (2) increases in primary air and fluidized materials result in an increase in desulphurization efficiency due to enhancing the movement of desulphurization material, especially, in lower part of the furnace.

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This paper investigates engine performance and emission characteristics with water-emulsified fuel including vegetable oil. The experiments used equal proportions of used frying oil and gas oil, biodiesel fuel from used frying oil, and equal proportions of rapeseed oil and gas oil as the base fuel. Performance tests of two types of single cylinder DI diesel engines showed that the NOx concentration and smoke density both reduced without worsening BSEC (brake specific energy consumption) with water to fuel volume ratios of 15 to 30% at a rated output. The paper also investigates evaporation and combustion characteristics of the water emulsions with basic experiments of suspended droplet combustion. Compared with water free fuels, the ignition lag of emulsified fuel droplets was longer while the combustion duration shortened with micro-explosion or puffing occurrence.

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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 circular jet equivalence ratio with the air flow rate kept constant and without PET-powder supply. PET-powder having a mass-median diameter of either 89.7 um or 145 μm and stoichiometric propane-air mixture are then issued into the high temperature region by varying the PET-powder mass flow rate. Appearances of the PET flame are observed using a high-speed video camera and PET particles are traced during their passages in the high temperature region. Variation of O_2 concentration fields due to PET-powder combustion is also measured in the PET flame. According to the results, overall limit conditions for effective burn-up of PET-powder are finally discussed.

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It usually takes a few weeks to analyze dioxins concentration in flue gas from MSW incinerators by official method. In order to reduce the required time for analysis, we have developed an on-line measuring equipment for pentachloro-dibenzofuran(P_5CDF)and a real-time measuring equipment for trichlorobenzene(T_3CB). The following results were obtained from field tests carried out using these equipments. (1) The concentration of DXNs emitted can be estimated and monitored by measuring the concentration of P_5CDF contained in flue gas using a ultraviolet ionization mass spectrometer(VUV analyzer)(2)optimum operating conditions to reduce dioxins emission can be obtained by the T_3CB measuring equipment which relates to dioxins' behavior inside furnaces real-timely, and (3) these equipments can be applied in adjusting operating conditions during trial operation of an incineration plant by monitoring them and for basic research and development.

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Recently, hydrocarbon system 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 can be suppressed below to a heat-resistant temperature by setting isobutane concentration to 8800ppm or less. Temperature to which all isobutane is oxidized becomes high under increasing of premixture concentration and space velocity.

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Melting treatment of fly ash from fluidized bed incinerators(450t/D) was successfully conducted by DC-joule heating system over 90days of continuous operation. The operation was broken down the specific characteristics of fly ash melting such as lots of volatile material of chlorides and contents of alkaline material by the detailed control of temperature to melting furnace and flow line of discharge out of furnace. Slag is available for reusing to be satisfied with the environmental standard of soil. Melting of joule-heating has long retention time of molten material with steady and calm operation enough to distribute the elements among products.

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Illegally dumped waste in Teshima includes a wide variety of substances such as ASR(Automobile Shredder Refuse), incineration ash, sludge, and soil deriving from granite, which permit some inclusions in the melted slag. Some treatments are shown to minimize the inclusions in the slag for the use of aggregate authorized by TR(Technical Report). They are, removal of slag containing soluble silicate followed by crushing and separation of aluminum and copper from crushed slag. The removed slag in appropriate for the aggregate is crushed and melted again to make them available, so that all the melting product may be recycled.

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Plasma type ash melting process is increasing attention as the method of volume reduction, detoxification and recycling of incineration ash from municipal refuse. This paper describes 90 days continuous operation result and utilization of the molten slag for Fuji-Yoshida City Environmental Clean Center that was completed in March 2003. To confirm that the slag can be utilized as civil construction material, we conducted investigations which are (1) distribution of slag particle size, (2) leaching of heavy metal for the slag, (3) physical properties of the milled slag, and (4) environmental assessment of the slag utilization and follow-up survey on quality of asphalt pavement surface.

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Ash melting technology is increasing attention as the method of volume reduction, detoxification and recycling of incineration ash from municipal refuse. To promoting the utilization of slag, we have been studying, including Magnetic-separating and Crushing process of granulated slag quality improvements as civil or construction material by means of Hot-water-treatment (treatment to make the slag's surface improve by high-pH hot water). This paper describes operation result and characters of molten slag (processed slag) for fuel melting furnace that was completed in May-2003.

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We developed the new technology for ash treatment, ash roasting. This method is more economical and easier of maintenance than ash melting. This paper describes the outline of reuse technic of roasted ash for the construction materials, for example, aggregate. We find that roasted ash have a good points in support strength and handling. Using this material, we can make a strong paved street. The recycle material from roasted ash, we call Koka 21, is already applied for a lot of road constructions in Mie prefecture.

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Bench and pilot plants with moving-bed reactors were constructed and examined to demonstrate the effective features of the new reactor. Polystyrene was readily decomposed to liquid products under the controlled temperature and residence time. The bench-scale experiments showed that the oil yields were varied, especially by the residence time rather than the reactor temperature under the pyrolysis and catalytic conditions. The product composition in catalysis, however, were varied with the residence time. Catalytic decomposition of polystyrene at the higher temperature and the longer residence time resulted in the increase of ethylbenzene, which is a stable component as fuel oil and organic solvent. Based on the performance of the pilot plant operation, the treatment cost was estimated at 50-60 yen/kg for 2000 t/y-commercial scale.

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Sapporo Plastic Recycle Corporation a commercial waste plastic liquefaction plant developed by Toshiba Corporation has been operating with high conversion rate of oil from waste plastic, over four years since April 2000, when the packaging recycling law on plastic packages was introduced in Japan. We have been to promote feedstock recycling by the product oil of this process to oil refinery, after the research and development with Japan Energy Corporation. First of all, it started to apply the remained distilled light oil in petroleum refinery from April 2004. All of the products and by-products obtained by the pyrolysis are feed stock recycled or energy recovered, except hydrochloric acid obtained from PVC. We estimated next plant by simplify from experience of SPR plant, it is possible to establish next plant much chipper, with low environmental risk, sticking together local society.

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We have developed the new chemical recycle system for waste polyolefin plastics using H-garosilicates.The catalytic degradation of polyolefin using H-gallosilicates was examined in present study using a bench scale reactor (1.0kg/hr) with continuous feeding. Yields of liquid compounds from high-density polyethylene pe11et(HDPE), which were aromatics in most cases, ranged from 40wt% to 60wt% in various temperatures(460〜680℃).The most suitable temperature of catalyst in the reactor was 510〜560℃.

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In recycling of glass wool waste, phenolic resin included in glass wool deteriorates glass quality and does the operation of a smelting furnace uncertainly. Therefore a large quantity of glass wool waste is disposed of as industrial waste. Then we have developed the glass wool waste recycling equipment using oxygen-fuel combustion. On this equipment, the glass wool is blowed into the high temperature flame, the phenolic resin is burnt rapidly. The glass part of the glass wool is hardened in the water tank, and is collected. We confirmed that the glass wool is disposed stably in this equipment. We achieved the glass collection rate 97% and Ig-loss less than 0.2%.

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Chemical tankers in Japan transport various kinds and large amount of chemical substances. Some of them have adverse effects to the human health condition. However emissions of cargoes to environment occur during tank cleaning operation that is conducted to avoid contamination with next cargo. The emission amount during tank cleaning operation corresponds to the residue amount in cargo tanks after unloading operation. Thus, to evaluate the pollution level caused from chemical tanker activities, it is necessary to estimate the residue amount after unloading. We built up a calculation model to estimate the gas residue amount in cargo tank after unloading operation. Combining with results by a calculation model estimating liquid residue amount, emission amount of benzene, recognized as human carcinogen, is estimated under various temperature conditions.

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The new and reliable dilution system has been developed. This dilution system has the following characteristics. One is that flow meters installed in this system, small sonic nozzles, are traceable to the national standard. And another important characteristic is that the whole system including piping is coated using Chromium Rich Passivation surface treatment, which. shows superior characteristics for adsorption and desorption against NO, SO_2 and VOCs. The periods needed to saturate to SPAN and to ZERO were within 5 minutes for NO and SO_2 and 10-20 min for VOCs. The differences between the concentrations calculated from the flow rate ratio of the dilution system and those measured by the analyzer were 1-2 % in NO and SO_2, which is almost the same as the standard uncertainty of the concentration estimated by the dilution system, 1.3-1.8%.

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Ash content in coal and/or waste products sometimes includes considerable heavy metals such as Pb, Cd, As, Se and Hg. In their combustion processes, these heavy metals are vaporized to flue gas due to their high volatilities, and a part of them concentrates in sub-micron particulates, those are difficult to be removed by conventional dust collecting equipments. Therefore, for the control of the emission of toxic heavy metals from various combustion plants to the air, it is important to grasp not only the total emissions of heavy metals, but also heavy metal enrichments especially in small particulates in flue gas. In this study, a simple and rapid analytical method to estimate heavy metal enrichments in particulates depending on their sizes was proposed, in which LIBS is applied to the direct analysis of dust classified by particle sizes using Electrical Low Pressure Impactor.

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Electron beam is one of the nonthermal plasma technologies, which can oxidize toxic chemicals through reactions with active species such as OH, O_3, and thermal electrons. These active species are produced by the electron-beam irradiation of wet air. This paper reports the application of electron-beam technology for the treatment of polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) from an actual municipal solid waste incinerator. Laboratory-scaled studies are also presented for the treatment of aromatic and aliphatic VOCs. Electron-beam technology is a promising method for the treatment of air pollutants at concentrations lower than approximately 100 ppm.

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Combustion experiments of model wastes using hydrogen chloride (HCl) gas in a laboratory-scale fluidized-bed reactor were performed to elucidate the role of each section of the incinerator in the formation of PCDDs and PCDFs. At first, homologue profiles of PCDDs and PCDFs are compared between the experiments of the model waste containing poly(vinyl chloride) (PVC) and that containing no PVC with HCl injected to the reactor. The similarity of the homologue profiles shows no difference between PVC in the waste and HCl injected in the role as a chlorine source in their formation. Then, combustion experiments of the waste containing no PVC were conducted supplying HCl at the different positions of the incinerator to investigate the PCDD/F formation in each section of the incinerator separately. The amounts of PCDDs and PCDFs formed largely decreased when HCl was not supplied to the main combustion section even though HCl was injected after it. The presence of HCl in the main combustion section is essential for their formation in the downstream sections. This indicates that the compounds that lead to PCDD/Fs in the downstream sections are formed in the main combustion section in the presence of HCl.

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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 on PM, such as carbon soots. 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 was investigated using the low temperature atmospheric pressure nonequilibrium plasma. As the result this time, the regeneration of DPF could be confirmed, and the regeneration temperature could be reduced from 600℃ to 300℃.

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High Temperature Air Combustion Technology (HiCOT) is a promising technology for the reduction of pollutant gas and improvement of combustion efficiency. This technology has been developed for industrial furnaces using gaseous fuel, and plenty of industrial furnaces in Japan have employed HiCOT in order to save fuel consumption and to reduce NOx emission. In this paper, HiCOT has been adopted to pulverized coal combustion which has been widely used in coal fired boilers. The effect of air temperature on ignition and NOx formation behavior is investigated using 30kg/h pulverized coal furnace. From the experiment, it is revealed that ignition delay is decreased by high temperature air and a stable flame can be formed even for high fuel ratio coal. This is due to the enhancement of volatile release from the coal. Also, fuel-NOx is reduced by increasing the air temperature. From the measurement of volatile and nitrogen release along the furnace, it is revealed that fuel-N is released in a strong reduction zone near the burner, and the rate of NOx formation reaction is decreased. Low-NOx behavior is also confirmed using 150kg/h pulverized coal furnace.

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We experimentally evaluate a performance and exhaust emissions of a four stroke direct injection diesel engine operating on water-fuel emulsions. Four types of water emulsified fuels of diesel fuel and biomass based fuels are produced after the suitable selection of emulsifier. The ratio of water to fuel oil was changed by volume from 0 to 30%. We use JIS # 2 diesel fuel, diesel fuel containing 50% volume waste food-oil (Blend 50), waste food-oil containing 50% volume polystyrene pylolysis oil (Blend PS),and soybean oil methyl ester (VDF) as tested fuels. The combustion characteristics and emissions such as NOx, CO, HC, HCHO, O_2, CO_2 and smoke, particle size distribution are compared with the case of diesel fuel. We found that (i)the CO emissions of water-emulsified fuels are higher than diesel fuel especially in the low load range. (ii)the NOx emissions of water-emulsified fuels are lower than diesel fuel in the almost load range, and smoke, PM emissions of water-emulsified fuels are lower than diesel fuel, (iii)fuel consumptions of engine operating on water-emulsified fuels are lower than original fuel in the whole engine operating range.

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We experimentally evaluate a performance and exhaust emissions of a single-cylinder, four stroke direct injection diesel engine operating on diesel fuel containing 40% volume waste food-oil (Blend 4P), Blend 4P containing 30% waste soybean oil and 30% waste animal fat (Blend 4P-S30, 4P-M30), waste polystyrene pyrolysis oil containing 50% waste soybean oil and animal fat (Blend PS and Blend PS-M), and waste polystyrene pyrolysis heavy oil containing 50% waste soybean oil (Blend PS-H). 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 diesel fuel. We found that (1)the NOx emissions of the fuel containing animal fats such as blend 4 P-M30 and Blend PS-M are lower than base fuel in the almost load range. (2)the CO emissions are lower than base fuel especially in the low load range.(3) Exhaust emissions of Blend PS-H are higher than another Blend PS in the over all range.

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For membrane filtration, maintenance management is very easy, and rejection performance of turbidity and bacteria is excellent. Since it is principally spreading on a small-scale water purification plant. Recentry, it is also expected to spread the middle and large-scale water purification plant. Therefore it is required the more efficient membrane filtration system, since it becomes mass processing by the large-scale water purification plant. By this study, it considers as a following subject: (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) Construction of an efficient method to watch over breaking hollow fiber (4) Examination of the recycling method for a disposal membrane module (5) Development and establishment of the chemical cleaning method, and examination of the non-chemical cleaning method (6) Evaluation and the proposal (case study) of efficient mass membrane processing technology For the purpose of establishing the design requirement of the membrane filtration water-purifying institution, it is an energy-saving and space-saving type at 10O,OOOm^3/day scale, the actual proof experiment is advanced. This paper reports the outline of this system and the result obtained until now.

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Although membrane filtration plants were introduced to purification plants in recent years, prevention from Cryptosporidium, pollution of tap water source, rationalization of management, etc is still remarkable. And those 84% of all are small-scale plants which treatment capacity is less than 1,000m^3/d. Recently, it is considered that membrane filtration plant will be introduced for more large scale plant where it is necessary to conserve energy and achieve space saving system. Authors are now studying the establishment of large capacity membrane system with energy and space saving by introducing monolith ceramic MF membrane. Until now, TMP has been stable at Flux 4m/d for about three months in a small-scale test plant.

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High-rate ballasted coagulation sedimentation process is able to form floes which have large specific gravity by using inorganic coagulant, organic polymer coagulant and microsand. Therefore, the space is compact and is able to reduce retention time of the whole process drastically. In this study, aiming at extremely compact water purification system, we are investing validity of both flow which combine ultra high rate coagulation sedimentation process with high rate filtration or microfiltration (MF).

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The dynamic filtration method produces a high permeation flux with a slight head loss and is considered to have the separation capability more than several times higher than the conventional sedimentation basin method. In this study, continuous demonstration experiments were carried out with the dynamic filtration applied to the wastewater treatment. The treatment performance in the nitrification-denitrification treatment of housing estate sewage and the filtration performance in the activated sludge treatment of food wastewater were verified. In the nitrification-denitrification treatment, high filtration performance and stable nitrogen removal performance could be confirmed. In the food wastewater treatment using a maximum 100 m^3/d pilot plant, stable treatment performance such that, for the MLSS 6,OOOmg/L, the flux was above 2m^3/m^2d on average and the permeate SS about 10 m/L on average, could be confirmed.

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We have newly developed a biological nitrogen removal system used the immobilized microorganism for strong contaminated wastewater such as the landfill permeate. It was discovered that a resistant bacteria for high concentration of ammonium ion, during the treatment of low ammonium wastewater. Applying this microorganism for the immobilization, we examine the growth condition and the efficiency of nitrogen reduction.

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A two-phase hydrodynamic model was used to calculate the distribution of gas volume fraction in an aeration tank equipped with diffused aeration system. The calculated gas fraction distribution was used to estimate the volumetric oxygen transfer coefficient (K_La) in the aeration tank. For modelling the turbulence in the liquid phase, k-ε model was used, while gas phase was modeled as laminar. 2-D simulations were performed for 5 full-scale and 5 pilot-scale aeration tanks having different tank configurations and diffuser positions. Under different conditions, the measured liquid surface velocities and were found to compare well with the prediction of hydrodynamic model. DO concentration was also calculated by defining a scalar transport equation.

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This papers describes operating condition of the sludge regenerated management center, Furano district environmental sanitation center ,in Furano City, Hokkaido. This facility was completed in January 2003. It consists of both human waste treatment facility and garbage composting facility. The former can treat 46kl/day human waste and 14kL/day septic tank sludge and the latter, where barks are used as indirect materials, can treat 22ton/day garbage. It has been operated correctly from the completion and discharges treated water under regulation value and produces good quality of compost every day for about one and half years.

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The discharge into the sea of chemical substances or tank washings contains such substances should be prohibited to protect marine environment from pollution produced by ships. Using much water to wash the tank is a burden to a shipping service and it needs heavy cost and much fuel for the incineration. Therefore a method of the reduction of the wash water is considered The washing with a water jet is studied experimentally. As the result, concerning the water jet nozzle scanning pitch, the scanning order and the residue viscosity, the relation of the wash water quantity and the content of the residue in washing discharge is obtained When the pitch angle of water jet nozzle is small and the scanning is done repeatedly from above to bottom, the quantity of washing water can be reduced.

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This paper describes development of failure prediction system for GHPs which is connected with the remote monitoring equipments. The remote monitoring center preserves and analyzes operating data to detect failure. The system developed has two distinct features. One is that it can diagnose GHPs when they are following cooling or heating load suitably. This can attain preventive maintenance prior to peak load season. The other feature is that diagnosis algorithm is designed to apply to various types of GHPs. The service using this prediction system has started in spring of this year by Tokyo Gas, and we are going to develop and improve algorithm every year.

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This paper describes the main features of a developed absorption/compression hybrid air-conditioning system meeting the request of utilizing the exhaust thermal energy from co-generation system with relatively small capacity of about 50 kW. In the hybrid system, the refrigerating effect of about 20 degree-C brought by a single effect absorption cycle with Water/Lithium Bromide system cools the condenser of the vapor compression type air-conditioner with R410A. This cascaded combination not only brings the compression power lowering but also makes thermally insulated type absorption applicable to the air-cooled absorption refrigeration. The design point of 56 kW cooling capacity machine driven by steam whose saturated temperature is 120 degree-C is determined so as to minimize the electric power consumption of the system within the safety operation range of the absorption cycle. The pool boiling test results of the generator core shows that the separate plate type reaches the generator design point. The performance test results of prototype with the cooling capacity of 4 kW almost pass the rating specifications.

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Cross Flow type of heat exchanger seems likely to have superior characteristics designing a large heat transfer surface area per unit volume. In this study, new approached version of counter flow type of heat exchanger by using a 45° inclined plate fin arrangement and employing inserted plate between the fins raw are proposed in order to be up heat transfer enhancement of over all heat transfer coefficient. Four types of exchanger, i.e., conventional cross flow type with inserted plate (I), converted counter flow type with inserted plate (II) (III), and conventional marketing type (IV) are tested by experiment as a parameter of the magnitude of exchanged temperature difference and the mass flow rate. Obtained data are discussed as a relation of effectiveness and number of transfer rate, and exergy transfer. It is cleared that new proposed counter flow type (II) (III) have interesting heat exchanging characteristics.

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This paper describes Marangoni-like phenomena observed in externally homogeneous closed systems and a possibility of energy usage as seemingly perpetual motion. We often witness the inner surface of bottles containing liquid is sometimes wet even when it was kept closed and not agitated. Liquid drops flow down the wall continuously and do not stop; drop formation on the wall is seemingly ever lasting. These phenomena resemble so-called Marangoni effect, which is usually interpreted in terms of non-equilibrium effects either applied from the surroundings or contained in the system itself from the beginning. From the second law of thermodynamics, these phenomena cannot persist in externally homogeneous closed systems, because non-equilibrium effects cannot persist there. But author found spontaneous upward motion of water in closed glass bottles persisted where no external non-equilibrium effect seems to exist. This strongly suggests Marangoni-like phenomena persists in externally homogeneous closed systems. Author propses a possibility of energy usage as seemingly perpetual motion.

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A method to making ice slurry is one of key technology for cold-energy storage system. This study has been performed to study the use of ultrasonic wave to remove the crystal-ice layer formed around cylinder continuously. In the experiments, ethylene glycol solution was used. It is found that the ice crystals were removed actively at the region that amplitude of displacement caused by standing ultrasonic-wave was large, and they slided to the region that the amplitude was small. After accumulating for short period, the ice layers were removed. The release of supercooling and crystal growth, morphology of crystal ice, and removal condition in the ultrasonic field were discussed in relation to strength of the ultrasonic wave and temperature of the cooled plate.

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Ice storage system is remarkable as one of solutions that equalize difference of power demand between nighttime and daytime as well as that diminish design capacity of air conditioners. This report shows methods how to design and to control the system for the efficient operating performance. Operating data in encupsuled ice storage system demonstrates that system COP becomes higher in a case that ice storage tanks and refrigerators are installed in a series connection. Compared to the parallel connection, COP of the refrigerator increases by about 2.3%, while power consumption of the brine pumps per demand decreases by 15.8%. Moreover, control with database calculated for efficient operation improves the system COP by 135.9% for the medium daily demand, which dominates annual operating efficiency.

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A dynamic-type of ice making cold thermal energy storage system using water-silicone oil emulsion with silane-coupler agent, (C_3H_5O)_3SiC_3H_6NH_2, has been proposed. Ice slurry was formed in a coil-shaped double tube heat exchanger. Brine was circulated in the outer tube, and the emulsion was circulated in the inner tube to form ice slurry continuously. Inner tube was made of fluororesin which was used to prevent ice from adhering to the cooling wall. This system was operated under various cooling conditions (flow rate of the emulsion and brine temperature). The operation of this system was continued for more than ten hours or until the tube choked. During the experiments, oil content and IPF_<in> (ice packing factor of emulsion at the inlet of the heat exchanger) were measured. It was found that the tube choked condition (the oil content of emulsion became under 5vol.% or IPF_<in> became over about 40wt.%) didn't change though the initial oil content was increased. And the tube choked when the oil content became under 5vol.% in case of an increased initial flow rate. But ice was formed continuously over about 40wt% of IPF_<in>.

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The aim of this article is to assemble an ice formation system in which a water-oil emulsion is cooled with stirring in an airtight vessel and to reveal the optimum condition of the system work. The emulsion which was a mixture of additive NH_2C_3H_6Si(C_2H_5O)_3 and water-silicone oil was circulated into the airtight vessel and frozen with stirring. The ice was formed by a batch-wise process and the condition of long operation without adhering of ice was investigated. We built the ice formation system and reveal the stable condition of the system continuous work. As ice formation time was long, the ice easily adhered on the inner wall by reason that volume ratio of ice in the vessel was increase.

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The study aims at designing silica gel-water advanced adsorption refrigeration cycle; the cycle called "Single-Double Cascaded Adsorption Cycle" is proposed to provide high performance. The proposed cycle consists of single stage cycle and double stage cycle; the cycle can use heat source with cascading and always supply chilled water through two evaporators. Therefore, the recovery efficiency value and cooling capacity of proposed cycle are expected to be higher than those of conventional cycles. The performance of proposed cycle is compared with those of conventional single stage and double stage cycles by simulation analysis. The results show that recovery efficiency and cooling capacity of proposed cycle are improved at heat source temperature between 55℃ and 80℃. Moreover, experimental results with 6bed adsorption chiller are compared with simulation results. The results present the suitability of simulation model; the advantage of Single-Double Cascaded adsorption cycle is presented experimentally.

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There has been a great progress in Adsorption Refrigeration Cycle research. Many researchers have introduced their methods to discover and improve cycle performance. This paper will present a new adsorption cycle known as Reheat Two-Stage, which has been evaluated numerically. The study aims to examine the possibility of improving adsorption cycle performance which uses low temperature heat source and environmentally friendly refrigerant. This paper will describe the cycle working principle and discuss the results obtained from simulations. The cycle performance is analyzed using cooling capacity and coefficient of performance (COP). The results show that cycle performance is extremely sensitive to driving heat source temperature. The results also show that cycle time and mass recovery time are influential factors on performance. This paper will also compare the performance of this cycle with Single-Stage and Two-Stage cycles.

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