In process plants, piping systems for gas services with high rate pressure reducing devices have a potential risk of acoustically induced vibration, resulting in material fatigue falure. To investigate the mechanism of acoustically induced vibration and to establish the method to predict the dynamic stress level in the piping structure, field experiment and numerical simulation using sound-structure interaction analysis were performed. The empirical data shows the effect of circumferential vibration modes, and the comparison between the results of experiment and numerical simulation gave the validity of the sound-structure interaction analysis. By using the sound pressure level estimated by the process condition and the result of sound-structure interaction analysis, quantitative evaluation of the piping dynamic response to flow induced noise can be done.

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It aimed at the thing to propose the technique of a practicable vibration and the noise forecast in a ferroconcrete structure by using the SEA method in this research, and a basic experiment with a ferroconcrete structure was tried. As a result, the following matters have been understood by this technique. (1) The energy characteristic of the entire element can be understood by the thing to use local experiment data of the element. (2) A ferroconcrete structure was used, proven, and the effectiveness of the noise forecast was confirmed.

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A rest room is required in comfortable living space. So this paper describes the improvement of sound quality of toilet flushing sound. An acrylic board model is made for taking a picture of the flushing mechanism by a high-speed video camera. It is found that the flushing sound generates broken bubble in water current, and the frequency characteristics of the sound depend on the size of the bubble. The relationship between sound pressure level of the flushing sound and sound quality is investigated by comparing with the bubble shape.

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An experimental method to analyze the damping characteristics of hydraulic components is proposed in this report. By using our 3-mirophones Method, the absorption coefficient, four terminal constants of the perforated panel in the liquid-filled piping systems were measured. Experiments were conducted on the various perforated panels at high pressure level. Moreover, the sound absorbing characteristics identified are compared with analytical model derived by T. H. Melling. Good agreements achieved suggest that analytical model is reliable enough to predict sound absorbing characteristics for perforated panels.

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Coincidence effect is important phenomena for development of sound insulation structures. Theoretical understanding concerning coincidence effect of infinite plate has been established, but detailed examination of a finite plate is not enough. In this paper, as a first step of detailed study on coincidence effect of a finite plate, vibration of the rectangular plate which is excited by sound pressure from a point source is simulated by using acoust-structural coupled analysis technique by BEM and FEM. And coincidence phenomena of a finite plate is visualized through comparison between surface distribution of sound pressure acting on the plate and vibration velocity of the plate.

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This paper proposes an active noise controller with Filtered-X Fast Transversal Filter (FXFTF) algorithm and Frequency Domain Adaptive (FDA) Algorithm in 3-Dimentional acoustic field which outside noise makes. Generally, in active noise control, Filtered-X LMS (FXLMS) algorithm is applied because of its simplicity and stability. However, FXLMS algorithm has a fault that the convergence speed is slow. On the other hand, some adaptive algorithms based on least squares method are known with faster convergence speed than LMS type algorithm although the calculated amount is large. If an algorithm based on least squares method is able to be applied to active noise control system, it is prospective that the field of active noise control is spread. From this point of view this paper picks up FXFTF algorithm and FDA algorithm based on least squares method. By means of Computer simulation and experimental analysis the performance of FXFTF algorithm and FDA algorithm is compared to that of FXLMS algorithm. With the result of the comparison it is shown that FXFTF algorithm and FDA algorithm have faster convergence speed than FXLMS algorithm in several acoustic field.

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This paper describes the active control systems for reducing floor impulse noise. The control system is comprised of actively controlled modular thin plates, which wholly cover the surface of concrete slab structure in the ceiling, and in each of which the mechanical vibration is controlled independently with bimorph type piezoelectric actuators. An active control system of modular plate is presented, where five sensors and actuators are applied to control low frequency modes of bending vibration in the plate. The control system is now under development, main subjects of which are; 1) designing of vibration characteristics of modular thin plate, 2) the active control system appropriate to the characteristics and cost reduction of the actuators and sensors. Subject 1) is mainly discussed below.

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This paper describes the active control systems for reducing floor impulse noise. The control system is comprised of actively controlled modular thin plates, which wholly cover the surface of concrete slab structure in the ceiling, and in each of which the mechanical vibration is controlled independently with bimorph type piezoelectric actuators. An active control system of modular plate is presented where five actuators and five sensors are applied to control low frequency modes of bending vibration in the plate. The control system is now under development, where main subjects are; 1) designing of vibration characteristics of modular insulation plate, 2) the active control system appropriate to the characteristics. Subject 2) is mainly discussed here.

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As one of the global research of smart board, vibration control system was developed to suppress the vibrations which harm the health of structure. CFRP board reinforced by stiffeners is a target structure. In combination with FBG optical fiber sensors, PZT sensors, PVDF sensors and laminated PZT actuators, all attached on the surface of structure, vibration control system was constructed. First of all, effect of rigidity change by stiffeners on vibration mode was investigated by FEM and experimental modal analysis. Then, based on these results, locations of sensors and actuators ard decided and distributed clustered control system was constructed. Finally, suppression effect by this system was verified.

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Visualizing and finding exact noise source locations on the surface of a moving vehicle is inherently difficult. A two-dimensional microphone array with high resolution was designed and synchronized with a visual sensor to acquire a picture of a moving source during a measurement. Experimental results show that a spiral array gives better resolution for moving cars and trains. Noise sources were visualized within 50 cm at 1 kHz with a microphone array 10 m away from the source.

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We visualized distributions of noise sources on the surface of a Shinkansen vehicle running at 360km/h for tests by using array microphones and a line sensor camera synchronized with a magnetic sensor on a rail. As the result, noise insulation plates of pantographs, side cowls around bogies and the smoothed doors structure of the crew's rooms are effective for noise reduction

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These days, household affairs such as night time vacuum cleaning and machine-washing have become commonplace because of dense residential areas and diversified living styles, resulting in the increasing necessity for low-noise electrical household appliances. Specifically, noise reduction for a compact-size electrical vacuum cleaner is difficult because it incorporates a high-speed motor in it. Catalog specifications itself cannot provide purchasers with real sensation of noise. Accordingly, they result in confirming the actual noise when they use it at home. Human also discriminates noises in terms of sound quality. Our experiment confirmed that the improvement in sound quality of noises radiated from the vacuum cleaner considerably contributes to the psychological noise reduction. Based on the results, we have installed a specially designed acoustic filter, a Helmholz resonator, into a vacuum cleaner, which is capable of absorbing harmonic high-level noise components involved in the motor rotation, thus alleviating users' sense of discomfort against the noises from the vacuum cleaner.

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Emitting mechanism of edge tone ware explained by Konig W. in 1912. Theoretical frequency of edge tone was shown by Kruger F. and Konig W. in 1920. However, re-study of generation process of edge tone is important for countermeasures of air noise from machines. In this paper, frequencies of edge tone, distributions of fluid velocity between a nozzle and an edge and static pressures around an edge were measured. Feedback of edge tone is confirmed and a noise source is specified by the measurements.

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An air conditioner is constructed with a fan and a heat exchanger around it. The heat exchanger tends to be close to the tips of the fan so as to miniaturize the product and allow a large capacity. However, it sometimes generates a noise like a weak whistling. The noise sources clearly seem to be from the part of the heat exchanger which is close to the fan tips. This noise is considered as a kind of a cavity tone and has been studied by many researchers over a long period. However the cavities between the heat exchanger fins are not enclosed and arranged continuously. It is considered that the difference in the static pressures between the inlet and outlet sides of the heat exchanger effects this noise. To reduce the noise of the air conditioner, it is important to clarify the relation between the noise and differential pressure between the inlet and outlet sides of the heat exchanger. To this end, a wind tunnel was used for a fundamental study of this phenomenon. The heat exchanger was let into the side of the wind tunnel wall with its main face parallel to the main flow.

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The purpose of this study is to realize the comfortable swinging fitted in the condition of the individual. A simple active rocking chair changing the driving force with heartbeat fluctuation is developed. The rocking chair is driven by a solenoid for safety and silence. The time in which the solenoid operates is proposed that the time is lengthened so that the stimulation may strengthen as the heartbeat period of human sitting on the chair lengthens, and the time is shortened so that the stimulation may weaken as the heartbeat period shortens. Then, the swing is evaluated using the 16 scales questionnaire. And it is confirmed that the comfortable swinging had been realized by the active rocking chair changing the driving force with heartbeat fluctuation. Especially, the evaluation for "the feeling of lively" with low evaluation in the uniform swing is high by fitting the swing in the condition of the individual.

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When operator in various industrial working area is exposed to noise, the working efficiency may be influenced by the acoustic environment. This paper describes; (i) the design proposal for the acoustic environment in consideration with the quantitative analysis of the working efficiency, (ii) the result of experiment by the evaluation method of work load, human impression under office work regarding the relation between noise, working efficiency and human impression, (iii) the optimum evaluation methods with the aim of comfortable environment and improvement of the working efficiency.

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To measure human's feelings and moods is very important for improving life. For example, that makes it possible getting rid of stress which caused by making a living and developing more attractive products. There are two techniques of evaluating comfort. One is the subjective method like the SD method and the other is the objective evaluation technique using bioinformation, such as electroencephalogram and electrocardiogram. In this article, the latter evaluation method is utilized for the evaluation comfort by using electroencephalogram and electrocardiogram quantitatively. The frequency fluctuation of brain waves which is said that individual difference is small is focused. The evaluation method of comfort mind is proposed.

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We, human being, hear 'twitter of birds', 'stream sound' etc. as comfortable sound. On the other hand, we hear 'sound scratching window', 'sound scrubbing styrene foam' etc. as uncomfortable noise. What is the difference between them? In this paper, the uncomfortable rates of 16 daily hearing sounds were evaluated at first, using method of paired comparison. Then, those sounds were analyzed by the human auditory model and wavelet analysis in order to find out causes of discomfort. Such characteristics of comfort and discomfort were found out that the former has calm rising up and down and the later has steep rising up and down, and that the former has sinusoidal vibratos in high frequency region and the later has irregular ones. But the auditory indexes which can evaluate the noisiness of machines were proved hardly to have correlation with uncomfortable rate.

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This paper presents a discussion of perception mechanism for infra, low frequency sound (ILFS), which radiated from industrial machines and facilities, and large structures. Now the permissible sound pressure level on health in the range from Infrasound frequency to audible frequency is discussed in European countries. But these recommended permissible SPL applied in this frequency range, which is based on the experimental data of laboratory may be unsuitable for the estimation of the effect of ILFS on health in the infrasound frequency rang, especially below about 10Hz. Approximately on the frequency range above 10Hz, Polish recommendation as A10 will be suitable in actuality as shown in Fig.3. Then, a perception mechanism of infrasound, which may be imperceptible physiologically as sound is viewed from the physiological perception mechanism, the bio-mechanism of perception is not controlled by the magnitude of physical stimulus, and is almost controlled by sensing the instantaneous change of stimulus. A necessity of a dynamic estimation of sound pressure level and sound frequency spectrum as a function of time is discussed.

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The gasification technical development of solid fuel is beginning to be taken up from coal and the biomass as a leading means to the large range of even waste these days. The merit of a gasification method is that manufacturing the gaseous fuel which is easy to use from solid fuel, and toxic substances, such as chlorine, sulfur, and heavy metals, are removable before using a fuel. The system characterized by gasifying municipal waste and automobile shredder residue using a pyrolysis kiln and a gas cracker was developed, and many processing data was able to be acquired. The design method of the energy and mass balance of the gasification system is being arranged from the processing result of a pilot plant with an amount of 4.6t/day, a 10t/day demonstration plant, and the commercial plant for 60t/day for automobile shredder residue. Moreover, amount of toxic substances containing dioxins is the minimum, and it was verified that a gas cleaning performance is high.

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Trace metal components in wastes evolve and/or concentrate in fine particulates during the combustion or incineration processes. Some of them may be emitted as a gaseous phase or fine particulates to the atmosphere. When released to the atmosphere, however, those compounds may cause adverse effects to the ecological system. In this study, the optimum sorbent to capture them during combustion is tested in burning dried sewage sludge at temperature ranging from 1073 to 1223 K, using an electrically heated drop tube furnace. Both formation behaviors of particulate mater and capture characteristics of trace elements by the optimum sorbent are discussed under practical combustion conditions. This study also conducts the leaching test of trace metals in the by-product.

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Fundamental pyrolysis and combustion characteristics of several types of biomass were studied, using a thermogravimetric analyzer. An electrically heated drop tube furnace was employed to elucidate the effect of the biomass addition on the combustion behavior, NOx emission characteristics and ash formation. The results obtained show that pyrolysis and combustion characteristics of biomass depend on lignin and cellulose compositions in the biomass. The biomass can enhance the ignition of the low-grade coal. However, NO and N_2O emission behaviors under the co-combustion condition resemble those under the coal combustion condition. When the only biomass is burned, fine particulates of less than 2μm are produced. However, the coal ash captures the fine particulates from biomass during co-combustion.

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Recently, it has been increasing exhausted waste abundance and the quality is also become diversing. Along with the diverse of composition of waste, the case that flammable substance is mized in the disposal process has been increasing and the burst and blaze hazard are also on the rise. In this study, it proposed the cause investigation of an accident increase and the accident prevention measures by using the risk analysis. It aims to investigate the ignition controlling effect by the ignition characteristic of the combustible gas that assumed in the pyrolizer in the carrier of the garbage truck and in the ripper in addition and the inert gas addition, and to obtain the indicator of the overall explosion-proof measures from these experiment results and the analyses.

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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 one year 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. Furthermore, char is generated in a pyrolysis process and also carbon is generated in a gas reform process. Both char and carbon are recycled as solid fuel or a reducing agent material. As mentioned above, high rate of recycling from ASR is realizable in this system.

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Low excess air ratio combustion brings about suppression of DXN, high efficiency of boiler and downsizing flue gas treatment because of high temperature and decrement of flue gas. However, it is possible that incombustibles gas, such as CO, increase at furnace exit under low excess air ratio combustion. The experimental and simulation studies are carried out with actual MSW incinerator (180ton/24h) in order to study the effect of combustion near solid phase and at secondary combustion zone. The simulation of incinerator includes solid phase and gas phase with coupling. The simulation results agree with the experimental results of temperature and gas composition profile. Under low excess air ratio operation, it keeps less than 2.0 ppm of CO and stable steam rate in commercial MSW incinerator.

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After deletion of limitation for bed heating rate in line with the repeal of design criteria (Kozo-Shishin), we designed and constructed new fluidized-bed incinerator with high bed heating rate of 600kg/m^2h by the application of lower fluidized-bed temperature and decreasing the primary air ratio. This paper describes the achievement of actual operation for new fluidized-bed incinerator with excellent performance, such as lower CO peak and low emission of DXNs under 0.01ng-TEQ/m^3N. Also, the simulation results match well with the actual operation data.

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This paper presents the results of an experimental study of the performance of a novel electrostatic separator. The separator consists of a conductive belt conveyor equipped with a plate electrode. The separation tests were performed on a sample containing 50% polyvinylchloride (PVC) and 50% aluminum. The influence of electric field strength and belt speed on the separation efficiency was investigated. Numerical experiments have shown the feasibility of obtaining extract contents of aluminum and PVC in excess of 99.99% and 99.46%, respectively.

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To develop utilization technology of wood resources, production of new materials from wood powder was tried. It was confirmed that molding of wood powder was possible by using self-adhesion ability of wood without using adhesive. For improvement of strength performance of mold materials, a preparation method of wood powder was examined. Wood was broken down in various conditions of temperature and moisture content. Mold materials were produced only from wood powder under steam processing of high temperature and high pressure, and the strength performance was investigated. It was confirmed that improvement of strength performance of mold materials was possible by preparing wood powder in the state of high temperature and high moisture content.

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Annealed bottom ash from municipal waste incineration was characterized for metal leaching. Influence of temperature, oxygen concentration in the atmosphere and treatment time on leaching behavior was investigated. Concentration of lead and chromium (VI) increased as temperature and oxygen concentration in atmosphere rose. Prolongation of treatment time caused increase of lead leaching and degrease of chromium (VI). Sintering experiment of 4 particle-size groups classified by sieves revealed influence of particle size on lead and chromium leaching. The experiment also showed correlation among concentration of lead in leachate, pH of leachate and amount of Gehlenite in ash observed by XRD.

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One of the leading methods to utilize waste incineration ash is the melting treatment, but this method has a disadvantage of high cost, because it requires plenty of energy. In search of technologies for effective utilization with less energy consumption and cost, we Kawasaki are now developing a novel technology where hydration reaction is applied. In the technology, waste incineration ash is solidified after the hazardous heavy metals contained are stabilized by mixing and mulling with additives and water, and then curing with steam. With this, solidified material can be used as civil engineering materials such as roadbed materials. In this report, the results of tests to manufacture sand and crushed stone utilizing waste incineration ash from stoker furnace are described.

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Characteristics of plasma melting furnace operation is discussed from a viewpoint of various kinds of ashes from different incinerator systems, namely grating-type incinerator and fluidized-bed incinerator. Ash chemical composition, slagging ratio and dioxins content data in three newly built plasma melting furnaces. These data show that the plasma melting furnaces can treat ashes both types of incinerators, and dioxins emission per one ton of municipal solid waste (MSW) treatment is almost the same for both types of incinerators together with plasma melting furnace.

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Refuse-incineration power generation is one of the requirements for realizing a resource-recycling-type society in response to society's need for consideration of the global environment, as well as for preventing global warming. Co-generation is undertaken as one of the important technological pillars supporting reduction of CO_2 and the combined cycle waste to energy is one such measure. The power generating system installed at the Clean Energy Center, which has been completed recently, has had some important improvements introduced in its system compared with the practical applications of the combined cycle waste to energy. One of these features is the efficient use of a pair of gas-turbine power generators, which has been realized through efforts to enhance profitability. We report in this paper what points among the others features of the Clean Energy Center, differ from those of other existing power plants of the combined cycle waste to energy.

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A bubbling-fluidized bed incinerator and fast fluidized bed incinerator (circulating-fluidized bed incinerator) has been used to incinerate sweage sludge. The multi-purpose fluidized bed incinerator, which has been developed from FFI, is expected to be dealt with dewatered sludge, waste plastic, waste oil, waste liquid and all of industial waste. The operating conditions and operating data obtained from actual plant using multi-purpose fluidized bed incinerator are described in this report.

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The pyrolysis gasification and ash melting processing plant at Toyohashi Waste Treatment of Recovery and Resource Center has been in commercial operation since April 2002 as the biggest plant of the Mitsui Recycling 21 system (R21). This system is designed based on the concept of scale-up from our model plant which is 24t/d of capacity, and also based on low releases of Dioxins, stable combustion condition and high heat recovery. It is confirmed that the main equipment of this system i. e., pyrolysis drum, high temperature combustion chamber and waste heat recovery boiler achieve stable performance. This paper describes the operation result of these main equipment on the view point of scale-up from the model plant and the first commercial plant of R21 for Yame Seibu Clean Centre (110t/d).

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The operating experiences of the Toyohashi Waste Treatment of Recovery and Resource Center of a Pyrolysis Gasification and Melting Process for Municipal Solid Waste (capacity : 400tons/day at 2 lines) are reported based on the operation during Apr. 2002-Dec. 2002. In this paper, we report on following results of the operation; (1) dioxins concentration less than 0.01ng-TEQ/m^3N, (2) waste volume reduction, (3) material recycle, (4) thermal recycle, (5) slag leaching performance and (6) heavy metal composition of slag for JLT19 method.

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We have newly developed thermal and material recycling systems for forestry biomass using indirect heated kiln. This is the application of our pyrolysis technologies for industrial waste and we have made several pyrolysis tests for forestry biomass. As a result, it is proved that the pyrolysis gas is utilized for thermal recycling and pyrolysis coke is utilized for not only solid fuel but adsorber, which can be used as substitutive material of activated carbon. It is expected the spreading of this method may develop the improvement of the maintenance of the forest and contributes to the reduction of greenhouse effect. We will continue to study to complete the system and the construction of our first utilizing plant with large capacity.

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Increasing concern about environmental disruption is requiring MSW incinerators further to reduce harmful effects on the environment. In response to the requirement, we are developing "K-ECO stoker incinerator" for the coming age, which features "Low environmental impact" and "High recycling efficiency". Applying FGR (Flue Gas Recirculation) to a plant with a capacity of 50t/d and optimizing the combustion control, we attained a flue gas reduction of 20% by reducing air excess ratio. from 1.6 to 1.3. In addition, dioxins concentrations in flue gas, bottom ash and fly ash were reduced due to higher combustion temperature by minimizing the excess air supply to the incinerator.

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We installed water cooled grate bars in a domestic MSW plant, and we confirm steady operation. No wear of the grate bars was observed after one year operation. We also applied exhaust gas re-circulation (EGR) system to domestic MSW plant. As a result, the following merits were confirmed compared with the case that EGR system is not used. -the air ratio was reduced to 1.3. -CO concentration at stack inlet has been reduced by 25% -NOx concentration at DeNOx tower inlet has been reduced by 31% -Flue gas quantity has been reduced by 9%

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Mitsui Engineering & Shipbuilding Co., Ltd. (MES) has developed a Pyrolysis Gasification & Melting Process Plant (Mitsui Recycling 21 or (R21)) which has a completely new incineration system. MES already received order of six commercial plants of this process and all of them are under operation with satisfactory results. Since the operation and maintenance of the R21 are different from those of ordinary plants. it is necessary for operators to have training and security operating guidance for a smooth operation of the plants. During the course of the R21 development. MES has established a dynamic analysis model of R21 which is based on physical equation for designing support and ability test of a control systems. By this training simulator developed. the training for skilled operators can now be made systematically in a short period.

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Recently, in order to consumer society shifts to Recycling-based Society, it is required for products' parts to be used long-term. Therefore we aim to prove the effectiveness for the protection of the environment and the resource by promoting reuse parts. In this study, from this point of view, we promote reuse parts in the case of recycling of End-of Life Vehicle (ELV). In this report, we paid attention to the light cars in the increasing tendency. We actually dismantled the light car and with the car disassembling data, we estimate the Life Cycle Assessment of cars. As a result, we proposed the guidelines about car's Disassembly-Oriented Design, and showed that using reuse parts is effective for resolving problems about environment and energy waste. And we also show that increasing kinds of reuse parts of the light car decreased environmental load more than now.

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Recently it is required to shift consumer society to Recycling-based Society. Therefore we proposed a concept for the product upgrading by adopting the new environment-friendly technology without wasting its life. In this study we aim to prove the effectiveness for the protection of the environment and the resource with that concept. In this report, we upgraded the regenerative braking system of an electric vehicle that converted from an internal-combustion vehicle. And we participate three games for EV. As a result, the drive range by one time charge became 103.1km. And compared with the internal-combustion vehicle, our EV reduced 40% of CO_2 and 20% of NO_2. And we proved the usefulness of our EV by winning these games

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In these years, increase of waste and exhaust of resource become major issues by the progress of mass productive, mass consumptive and mass waste life style. As the correspondence, the construction of circulation type society is required. For constructing such society, the consideration to 3R (Reduce, Reuse, Recycle) at the design and manufacture stage of the industrial product become very important. As the correspondence to Reuse and Recycle, the improvement of disassembling property of the products is especially required. Therefore, we propose the index that we assess at disassembling property of the products quantitatively. This index is that we roughly estimate the real disassembling time from the information on the design stage, as the disassembling time becomes the guideline that we assess at disassembling property. In this study, we aim at establishing the method of the determination of the index to apply the Design for Disassembly Assessment Index to various products

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Recently, it increases the importance of concern for 3R (Reduce, Reuse, Recycle) at the design phase of manufactured product toward creation of a recycling society with a low impact on the environment. Especially, improvement of product disassembly efficiency is essential to concern for Reuse and Recycle. Therefore, in this study, we take up office furniture as one of manufactured product, and disassemble experiment on them, analyze their experimental data. Then, we make a quantitative assessment of office furniture disassembly efficiency by the Design for Disassembly Assessment Index that we developed to make a quantitative assessment of manufactured product from the experimental results. In addition, we aim at the proposal on the design method of disassembly of office furniture.

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