Acoustic property of a series-coupled resonant chamber is studied. The chamber has two rectangular cavities and two slit-shaped necks in series. The impedance of the end surface of the second cavity is changed from that of a rigid wall to those of soft polyvinyl chloride sheets with several thicknesses. The reflection coefficient of the chamber for the normal incidence of the plane wave is measured using an acoustic tube. The lower impedance of the end surface makes the resonant frequencies higher and the resonant effects larger, especially for the first resonance. An analytical model for BEM (boundary element method) calculation is composed for simulating the experimental model of the chamber. The measured impedance of the end surface is applied to the BEM model. Although the absorption effect of the necks is ignored, the resonant frequencies are moderately predicted by the BEM calculation. For the prediction of the resonant effect, however, the acoustic property of the necks should be considered.

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This paper concerns the improvement of ear-plug type earphones performance. The transmission characteristics of the ear canal with/without earphones are different. Therefore, the sound quality of the earphone is a little poor compared with audio speaker. In addition, it is well-known that the acoustical characteristics of ear canal are individually different with each listener. Then, we predict the acoustical characteristics of ear canal with ear-plug type earphones by using transfer matrix method and study on how to improve the transmission characteristics of the ear canal. In this paper, a method for adjusting the resonance characteristic of the ear canal with earphones to the characteristic of the ear canal of AV speakers without earphones using digital filtering technique is proposed. In the method, the sound improvement reproduction performance is verified on the basis of experiments.

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In this paper, in order to solve the characteristics of the radiation sound field generated by vibration of a flat elastic plate in a small enclosure with rigid wall we try to apply the numerical simulation technique using the finite difference time domain (FDTD) method to the coupled analysis of the vibroacoustic characteristics. The update equations for the FDTD simulation in the sound field and in the elastic body modeled by the isotropy material are coupled at the boundary of both the mediums. Numerical results show that the frequency response changes depend on the value of the material constant of the elastic plate and/or the volume of the enclosure. Since the experimental results using a vinyl chloride plate and an aluminum plate show the same tendency with the numerical results, the validity of the numerical simulation using the FDTD method in this paper is confirmed.

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An acoustic transparent wall was developed and applied to car air conditioner ducts for the purpose of noise reduction in a car cabin. The acoustic transparent wall is a plate through which sound can pass easily but flow cannot pass. This technique has already been applied to casings and ducts of ventilating fans to reduce the inlet and/or exhaust noise. In this paper, firstly, basic experiments were performed using a test duct with the acoustic transparent wall to obtain basic design data. Secondary, this technique was tried to be applied to a car air conditioner duct, obtaining roughly lOdB, at the maximum, noise attenuation at air exits.

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A boiler and a heat exchanger ate widely used in various plants such as power plants and chemical plants. However unexpected high level sounds are generated when these plants are operated and it becomes a serious problem. This kind of problem is called the acoustic resonance and it has been considered that the resonance generates when the frequency of the vortex shedding behind the tube bank coincides the natural frequency of the duct system. When a boiler was test operated on ahead at one factory, unexpected high level sounds were generated Then I examined the cause and the countermeasure based on measured data of sounds. As a result, it was clarified that the cause was the acoustic resonance and the insertion of the long baffle plate was effective as the countermeasure. In addition, the counter mechanism ofthe insertion of the baffle plate was not arising the resonance frequency ofthe duct but the decreasing of the energy which the vortex gives to the acoustic field of the duct.

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The low frequency noise is not clearly defined but is generally taken to mean noise below a frequency of about 100 to 150 Hz. Noise at frequencies below about 20 Hz is sometimes referred to as infrasound and this type of noise presents even greater difficulties in its measurement and assessment. The objective of our study is to suggest practical means of reducing the low frequency noise emanating from the opening of soundproof houses. This paper describes an experimental study on the alleviation of low frequency noise (20Hz) by the active noise control (ANC) in a subscale model house.

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Local active noise control systems create a zone of quiet around a physical error sensor location. The zone of quiet is generally small, and as such, the physical error sensor is placed at the desired location of sound attenuation, which is usually inconvenient. Virtual sensing algorithms have been developed to aim for creating the zone of quiet at virtual sensor location that is remote from the physical error sensor. However the sound attenuation of the traditional virtual sensing algorithms worsen by change of primary source location that alter the transfer characteristics between a virtual sensor and a physical sensor. This paper presents a method to maintain the sound attenuation at a virtual location in change of sound incident direction of primary source and show positive results of experiments in an anechoic room. The proposed method estimate sound incident direction of primary source to use signals of two microphones and be able to switch between an appropriate filter that is measured in preliminarily identification stage to estimate signal at virtual sensor location.

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Calculating vibration and noise with a high degree of accuracy is needed to estimate the radiated noise induced by the electromagnetic force from a motor. In the case of inverter motors, rotation speed and load leads to change in frequencies and amplitudes of electromagnetic force harmonics. We describe the development of a way of analyzing frequency response of electromagnetic vibration in the above conditions. We measured and calculated a sample motor's vibration of rotation orders that have a dominant affect on the overall vibration, and compared levels of vibration velocity. We calculated both rotation speeds and vibration velocity levels with three observable peaks with a high degree of accuracy.

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It is necessary to understand the vibratory properties of a track and a wheel in order to evaluate the rolling noise. In this study, focusing on the vibration of a wheel, we measured the accelerance of the corrugated wheel by the impact test. Then accelerometers were temporarily placed on the tire and web of the wheel of a vehicle which runs on a narrow gauge, we have measured the acceleration of the rolling wheel. In addition, we reported the vibratory properties of a wheel with a wheel flat and passing a turnout.

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This paper investigates generation mechanism of abnormal noise due to automotive rearview mirror in closing vehicle door. First, the signal of time history about sound pressure and acceleration is analysed by using a digital filter for transient response. Second, the countermeasure for the vibration control is examined, the effects of countermeasure to the abnormal noise are verified by comparison of sound pressure and acceleration with and without countermeasure. Finally, the signal of time history about acceleration simulated contact phenomena that occurs on the rearview mirror is generated for the purpose of investigating the generation mechanism.

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Rolling noise is generated by the vibration of wheels and rails due to the excitation force, caused by roughness on the surfaces of the wheels and rails. Theoretical models, such as TWINS model, have been widely used to gain better understandings of rolling noise. In this paper, the model is applied to Japanese railways and validated in terms of vibration and noise. Through the validation work, it is shown that the predictions show a close correlation to the measured values. For the noise spectra, the contribution of the rail to rolling noise is found to depend on the type of tracks.

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In the present experimental study, the authors try to clarify the characteristics of the flow around and inside a cross-flow impeller in a typical geometry, over a wide parameter range of an aspect ratio L/D_2. In order to eliminate the complicated casing factors, the impeller rotates in open space without any casings. As a result, by using hot-wire-anemometer measurements and by conventional flow visualisations, the authors divide the flow around the impeller into three areas, and observe the eccentric-vortex revolution inside the impeller. Using a particle-image-velocimetry technique, the authors quantitatively show velocity distributions, whose accuracy is checked in comparison with the hot-wire-velocimetry results. Then, the authors define the outflow rate Q_o but of the impeller and the maximum vorticity ω_<max>. To conclude, the aspect ratio effect upon the outflow-rate coefficient C_<Qo> is not negligible at aspect ratios (L/D_2)'s less than unity. As well, ω_<max> attains the maximum value at L/D_2 = 0.6. In addition, at L/D_2 = 0.6, we futher reveal minute fluctuating pressures on an impeller's end wall.

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In the present paper the attention is focused on the characteristics of aerodynamic sound radiated from tandem finned cylinders exposed to cross-flow. Several spacing ratios between the tandem finned cylinders ranged from 1.3 to 6.8 are tested for a Reynolds number of 1.7×10^5. We measured the spectrum of SPL and flow velocity for bare and finned cylinders with the fin pitch ratio of 0.16. As a result, we found that the peak SPL and Strouhal number of vortex shedding for the tandem finned cylinders depend on the cylinder spacing ratios as well as those for bare cylinders. The peak SPL for the tandem finned cylinders decreased rather than that for bare cylinders. This suggests that the fins suppress the aerodynamic sound for the tandem cylinders with spacing ratios ranged from 1.3 to 6.8. Strouhal numbers were calculated by using the measured values of peak frequency and the equivalent diameter of finned tube. The Strouhal number of tandem finned cylinders agreed well with that of tandem bare cylinders for large spacing ratio. However, as the cylinder spacing ratio decreased the Strouhal number closed to 0.18 which was larger than the case of bare cylinders.

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Effects of cross cylinders placed either the upwind or the downwind sides of two parallel cylinders were examined for various pitches and positions of the cross cylinders. With cross cylinders placed downwind, aerodynamics sound becomes weaker with decreasing cross cylinders pitch. But placed upwind, aerodynamics sound doesn't change essentially. Measurements of the mean velocity field show that cross cylinders tend to elongate recirculation region of the upstream cylinder and to make the point of vortex roll up backward.

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To measure sound absorption coefficient under parallel flow is studied through experiment and numerical analysis of three dimensional sound field. The dimensions of the measuring space are 600mm high, 600mm long and 50mm wide. Both boundaries of the space are connected to duct silencers to pass air flow. The boundaries of this measuring space must be non-reflecting to apply two microphones technique for measuring sound absorption coefficient. The sound fields with these boundaries are computed to evaluate the degree of non-reflecting for some numerical models to compare the experimental data. After ascertaining the validity of this measuring space, the effect to sound absorption coefficient of perforated panel with air space under parallel flow is measured.

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As a lightweight and low-cost noise reduction countermeasure, the author has developed a system to reduce the transmitted noise caused through panels by fixing noise insulation panels consisting of thin plates, piezoelectric materials and control circuits. In the case where an inductance circuit is used as a control circuit, a resonant circuit is made between capacitor of the piezoelectric material and the inductance circuit, and the transmitted noise reduced in range near the resonant frequency. This paper has described a way to spread the frequency range of control by double layer noise insulation panels with piezoelectric material. We clarified the influence given in the noise reduction effect of an air layer between upper and lower panels by the experiment.

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On active noise control in 3-dimensional acoustic field, a control effect becomes worse when an evaluation point moves. Against this problem, we proposed a control algorithm using filter map. Validity of this algorithm was shown by simulations and experiments. To use the method, however, the adaptive filters must be accumulated in a controller so that the required memory becomes large. We use an IIR filter in order to reduction the memory in this paper. The filter is configured by tapped-delay-line structure and lattice structure. Moreover, an algorithm for updating the filter is proposed. The validity of the algorithm and the filter is shown in numerical simulations. The results shows the algorithm can calculate desired characteristics and poles of identified system.

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Light wall structures with high sound insulation performance are desired to be developed for houses and fuselage of vehicles. In this paper, a new light sound insulation structure is proposed. It is constructed with light inflated membrane bound by hard wire nets. By impedance tube tests, the proposed structures were proved to have not only high but also adjustable sound insulation performance by tuning the inside air pressure, which means stiffening the membranes. This structure can also construct light but high-performance sound insulation panel by being inserted between light double walls.

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In the paper, Fast Transversal Filter (FTP) and Eigenvalue Equalization LMS (EELMS) adaptive algorithm are introduced into feedback Active Noise Control (ANC) system to gain higher noise attenuation. A kind of active noise barrier, which uses Active Noise Control Units (ANCU) to create an acoustic soft edge boundary to reduce the diffracted noise, has been developed. In the ANCUs, feedback ANC system is used because of the simplicity of its hardware. However, conventional feedback LMS (FB-LMS) used as the adaptive algorithm in ANCUs cannot minimize the sound pressure well enough to create the soft edge boundary. To improve noise attenuation, FB-FTF and FB-EELMS are proposed. Simulation and experiment show that both FB-FTF and FB-EELMS perform better than FB-LMS. Moreover, the noise insulation performance of active noise barrier is calculated by Boundary Element Method (BEM) in the paper.

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Structural bone noise in a railway vehicle, which is radiated from the floor panel that is vibrated by the force from the bogie, is one of major components of the interior noise. The conventional countermeasure to the structural bone noise has been to isolate the vibration between the floor panel and floor structure of the car body. When floor panel is large size, the noise that is radiated according to the vibration mode, therefore, the radiated noise into the cabin become to be complex condition. This paper describes the outline of the new type floor panel that is divided to small panels in size and possibility to suppress the structural bone noise by the simulations.

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It is necessary to examine what kind of vibration and swinging is comfortable, in order to develop the comfortable human-machine interface using vibration or swinging. This study is focusing on the fluctuation in the period on the rhythm produced by the human; especially the stroke interval of the air stick is examined. The air stick is a simple version of the devil stick which is a kind of the main street art. First, the portable measuring system of the stroke interval is developed by sticking two strain gauges on each hand stick and putting a wired battery driven strain amplifier and a portable data recorder in a knapsack which the performer wears. Then, the fluctuation is measured and the power spectrum is examined. As the result, it is clarified that the power spectrum shows the tendency of downward-sloping in the low frequency range, and it shows the relation of about 1/f averagely.

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Experimental Statistical Energy Analysis (ESEA) is applied to analyze the vibration energy flow on violin body. The violin body is subdivided into 6 SEA subsystems. The analysis can identify the power flow through the subsystems and the power input into each subsystem during the impact excitation at the bridge which connects the strings and the body. The analysis results for two kinds of violin are compared. It is shown that three pieces of knowledge concerning on the better violin are obtained, 1) damping of the body structure is small, 2) the frequency distribution of power input into the body is in inverse proportion to square root of frequency and 3) the energy on the top plate is propagating through the sound post into the back plate. The fundamental discussions on the knowledge 2) and 3) are carried out.

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In order to predict interior noise of automobiles, aeroacoustics simulation was carried out. Generally, flow fields are calculated in the time domain. Therefore, acoustic analysis of interior noise caused by aerodynamic noise and force should also be solved in time domain. CIP method is suitable for time domain wave equation analysis. In this investigation, we attempted to apply the CIP method to calculate the Lighthill equation. The simulation results showed this method is possible to calculate accurately the aerodynamic noise. Moreover, the results showed that the contribution of aerodynamic sound around a car body to the interior car noise is larger than that of the hydrodynamic pressure fluctuation of vehicle surface.

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The tube banks are set up in the duct of heat exchangers such as boilers etc. When the frequency of Karman vortex behind the tube banks is close to the natural frequency of the duct, the self-sustained tone is generated. Generally, the method of inserting the baffle plate in tube banks is adopted as counter measures of self-sustained tone. However, when there is a space called cavity between tube banks, the method of inserting the baffle plate has not been established. Then, to examine the generation mechanism and the countermeasure of the self-sustained tone for tube banks with cavity, the experiment and the analysis were carried out in this study.

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It has been very important to resolve aerodynamic and aeroacoustic problems relating to pantographs on high-speed trains. In this study, the authors attempted to reduce aerodynamic noise generated by the pantograph by using synthetic jet actuators. Numerical and experimental test results indicate that the synthetic jets can stabilize flow around a pantograph head, which is one of the dominant noise source of the pantograph, resulting in reduction of its Aeolian tone.

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The value of the aerodynamics noise generated from the inside of a traction motor was computed at the position 1m apart from the outside of a traction motor with the aid of the general-purpose heat fluid analysis software. This calculation results showed a tendency of frequency spectrum the actual one. In this calculation, it was shown that the sound power level in decibels grew large in the vicinity of the entrance of the cooling duct inside the rotator of the traction motor. The acoustical countermeasure against the noise from the cooling duct was taken by rounding off the edges in the vicinity of the cooling duct entrance. The effect of the acoustical countermeasure against the noise and the effect of the noise of the cooling fan inside and outside of a traction motor were verified by simulating the sound pressure change. These analytical results are reported in this paper.

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The experiments on converting Japanese MSW into chlorine-free solid fuel using the combination of the hydrothermal process and the water-washing have been performed. It was observed that after the hydrothermal process, the organic chlorine in the product was reduced and converted into water-soluble inorganic chlorine due to dehydrochlorination effect as well as reaction with the alkaline content of MSW. Water-washing experiments were then conducted to obtain chlorine-free products with less than 3,000 ppm total chlorine content and identify the influencing parameters of chlorine removal by the washing process. In this research, a thermogravimetric analysis to compare the combustion characteristics of products before and after the washing process was also performed.

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It is important for environmental protection to use waste materials effectively. In this work, we conducted fundamental researches on the application of carbonaceous materials from waste as a reductant for iron oxide. Carbonaceous materials from waste (carbonized municipal waste, carbonized biomass, canbonized sewage sludge) were mixtured with hematite reagent The mixtures were heated up at the temperatures of 1000-1200℃ in N_2 gas by using thermo gravimetric analysis (TG) or batch furnace. In the reduction experiments, weight changes and concentrations of generated gases from samples were measured by electric balance and micro gas chromatograph, respectively. Weight changes ratio was calculated to compare reaction rate and reactive character.

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Gasification technology that can produce useful gases such as hydrogen from waste has been developed because both the disposal of waste and the energy recovery are major current issues in the area of waste management and sustainable use. One of key technologies in this system is to effectively reduce the emission of by-products such as tar components. Experiments are conducted for wood chips and RPF materials by using a series of gasifier and tar decomposer equipped with catalyst bed in two temperatures of 750℃ and 810℃ in gasifier. Methanol synthesis from gasified gas was also tested. The results show that tar can be decomposed over 80 % efficiency, and this value was lower than expected because the temperature of catalyst bed was slightly low. The tar concentration after tar decomposer in higher temperature condition was less than 150 mg/m^3. The results regarding to polycyclic aromatic hydrocarbons (PAHs) were also discussed.

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A novel low temperature process to recover base oil from waste lubricating oil is proposed in this study, which is based on solvent extraction with membrane. In this process, organic solvent is circulated in a closed loop, representing a resource saving technology. Residue consists of only impurities in waste lubricating oil, such as suspended particles, aqueous droplets, soot and tar, representing a waste reducing technology. This process includes a fractional distillation, too, but it is for separating out organic solvent from oils. Then, temperature for fractional distillation is lower than 100 degC, representing energy saving technology. Rubber film is utilized as membrane in this process. Rubber film has swelling property when it is immersed in organic solvent. Expanded polymer network structure works as filter to separate impurities from oil dissolved in solvent. Objective in this paper is to verify the feasibility of solvent extraction with rubber membrane to recover base oil from waste lubricating oil. Effect of extraction period, solvent volume and extraction temperature on both yield and quality of the extracted oil was experimentally estimated. Quality of extracted oil was evaluated through measurement of sulfur, carbon residue and carbon number distribution in oil molecules.

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The purpose of this paper is to make high concentration methane from digestive gas by separating carbon dioxide appropriately out of the digestive gas generated in sewage treatment equipment. As the new removal technique of the carbon dioxide in digestive gas, we proposed using "Non-air-bubbles dissolution equipment." It can dissolve gas efficiently into a solvent liquid by being filled with digestive gas in a tank, putting pressure, and passing solvent water in it. Digestive gas is gas which makes methane and carbon dioxide the main ingredients. Generally, the ratio of methane to carbon dioxide is about 6:4, and contains a lot of carbon dioxide. The digestive gas used for this experiment was 58% of carbon dioxide and 42% of methane. As a result of dissolution / removal experiment, about 90 percent of carbon dioxide was able to reduce the content carbon dioxide in digestive gas in dissolution time about 3 minutes. Thereby, methane concentration became a maximum of 87% from 42 %, and it was able to make high concentration methane from digestive gas.

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Removal of cadmium from the cadmium solution using various microorganisms was examined. Gram-positive bacteria and actinomycetes were removed larger amounts of cadmium than other microorganisms, such as gram-negative bacteria , yeasts, and fungi. Arthrobacter nicotianae LAM 12342 can removed the largest amount of cadmium, which removed 547μmol cadmium per g dry wt. cells. The removal of cadmium using A. nicotianae was affected by the solution pH, concentration of cadmium, cell amount and temperature. Theremoval of cadmium was very rapidly.

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The removal of chromium (Cr(VI)) from the aqueous Cr (VI) solution by adsorption and reduction using immobilized persimmon tannin was examined. Most of the Cr (VI) was removed by adsorption using immobilized persimmon tannin. However, a part of the Cr (VI) was reduced to Cr (ni) by immobilized persimmon tannin and was passed through the column. Most of the Cr (VI) adsorbed couldn't desorbed by the alkali solution, such as sodium carbonate and sodium hydroxide. However, half amount of the Cr (III) adsorbed was desorbed using 0.1M HNO_3 solution.

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Some problems of popouts were reported when municipal solid waste melt-solidified slag was used for concrete aggregates. Therefore, Japanese Industrial Standards, JIS A 5031 was revised in July 2010 to introduce information about popouts. However, there was no applicable regulation in JIS A 5031 for popouts when melt-solidified slag was used for concrete aggregates. The popout test procedure has been investigated at Japan Testing Center for Construction Materials (JTCCM) since 2009. In this report, the test results of popout and Ca solubility, which were summarized of test procedure draft at JTCCM, were reported by using the melt-solidified slag. The melt-solidified slag was generated at municipal waste gasifying and melting plants in Japan. The test result of Ca solubility was available for pre-estimating of popouts. To prevent popouts, it was confirmed that an aging treatment of melt-solidified slag was effective.

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With this, in 2002, put into force was the Law for the Promotion of Utilization of Recyclable Construction Resources. Under this law, wooden wastes recycling plants are in operation. In large-sized recycling plants where disassembled wooden wastes are chipped by crusher and reproduced into compress - formed board through their drying process, it is a tangible serious problem on-site that exhausted gas emitted from them causes erosion at impellers of the fan, duct and cyclone separator. In a past report, we clarified the following things; (1) On the eroded surfaces of impeller, a series of ripple patterns which of perpendicular to the impingement direction of chips is found. When this ripple pattern is formed; of the erosion become fast-growing. (2) The relation between operating conditions and erosion, which has been made clear by observing eroded impellers of the fan. To be concrete, velocity of air stream has a great influence on the development of erosion; the value of 30 m/s is one dividing point and has been proved to be a value of great importance. Based on such a result this time, from the result of data of the erosion of the ductility metal materials which accumulated in this laboratory to erosion and the materials characteristics, it became clear that a correlation was recognized.

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The amount of coal ash exhausted from the recent power plants has reached 1,200 tons every year in Japan. Coal ash is generally classified into two types; fly ash and clinker ash. Since the recycling of fly ash generally becomes popular, comparing the recycling of clinker ash, we tried to make sintered porous material from clinker ash effectively. However, it has not been clarified how physical properties and particle size of clinker ash powders affect the performance on use. In this study, we tried to produce two types of sintered porous materials with the clinker ash powders of different particle sizes and to measure their characteristics. As results, it was found that these clinker ash porous materials were enough suitable for water retention block, and also that the block produced by small particle powders showed higher evaporative performance.

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JFE Engineering has developed the advanced stoker-type incineration system "JFE Hyper 21 Stoker System". It is equipped with some new technologies to meet requirement to a municipal solid waste (MSW) incineration system. Main technology of this system is High Temperature Air Combustion Technology (HiCOT), which realizes low excess air combustion. This paper describes results of the numerical simulation of combustion behavior in JFE Hyper 21 Stoker System.

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Presently, there are two known ways of removing HC1 and SOx from general waste exhaust gas, the dry- and the wet method. Within the ,,dry-method", the ,,slaked lime flue injection-method" and the ,,sodium-bicarbonate injection-method" are known. In case of strict regulations concerning the amount of HC1 and SOx in emitted exhaust gas, the ,,slaked lime flue dry-method" has the disadvantage, that the process of injecting slaked lime flue gas is difficult, and that hight amounts of slaked lime flue are needed to reduce the concentration significantly. The ,,sodium bicarbonate injection-method" on the other hand, makes it easy to reduce the concentration below required levels, but costs for sodium bicarbonate itself are very high. To overcome the above-mentioned limitations, our company has developed a method, which is able to significantly reduce HC1 and SOx levels in exhaust gas by using sodium hydroxide. In this paper, we will elaborate this method, as well as presenting the results of a real-life experiment, where incineration facilities were able to reduce the concentration of emitted HCl,SOx to bellow a level of 5ppm through implementing our method.

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Recently, highly effective power generation in waste incineration is required from needs of the CO_2 exhaust control. On the other hand, a severe self-imposed restraint values of their exhaust gas are adopted in various municipalities for regional environmental preservation. So, in many cases, the catalyst denitration tower with which the steam heating is needed on the downstream of the exhaust gas dust collector is set up. This study has aimed to satisfy both of the CO_2 exhaust control needs and regional environmental preservation with satisfying the self-imposed restraint value only by the S.N.C.R (Selective non-catalytic reduction for NO_x emission control) omitting the catalyst denitration tower. We report on the S.N.C.R examination in the numerical simulation related to the denitration reaction and in the real furnace.

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JFE Engineering Corp. has provided ten facilities of high temperature gasifying and direct melting plant in Japan. These plants are able to treat various kinds of waste, such as municipal solid waste (MSW), industrial waste, ash, refuse derived fuel (RDF), asbestos, etc. Recently, a social demand of reducing the coke consumption is becoming larger. In this situation, JFE Engineering Corp. has studied various methods of reducing the coke consumption. In this paper, we show test results of application of Bio-Coke as an alternative energy resource.

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Bio-cokes, developed by Kinki University (domestic patent No. 4089933), can utilize unused biomass and be used as a coal-coke substitute in large-scale industrial processes such as foundry cupola furnaces. Bio-cokes are expected to serve as a technology corresponding to (1) reduction in the amount of the CO2 generation for the global warming prevention; and (2) rise of the price of coal coke. In preliminary tests conducted at Kinki University, it was confirmed that Bio-cokes could be manufactured from various raw materials such as used tea leaves, wood waste, etc. This paper reports our current effort to optimize manufacturing conditions of a mass-production facility of Bio-cokes. This study confirms the pressured solidification characteristics of biomass (using tea scum as the raw material) with varied parameters such as heat process temperature, smashed size, pressure, and initial water content. Thermal analysis of the material explains why the manufacturing process does not change material weight when setting the heat process temperature at 453K. The optimum pressure for effectively obtaining a high specific gravity is constantly around 20MPa in spite of different smashed material sizes. There is the optimum initial water content to achieve the highest specific gravity, which is very close to the value based on the true-density.

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

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It is necessary to construct the information network system which constituted by consumer, producer and administration, etc. in order to plan the optimum recycling system. This study constructed the algorithm which deduced preferred recycling routes of desktop PC based on dispersive product information from the viewpoint of material resources. This model was constructed by applying multiagent system. By the agents with the criterion respectively affecting the product and waste parts database, it becomes possible that the ideal recycling map is calculated.

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