This paper concerns the improvement of room acoustics of space habitation. When aiming at comfortable acoustical environment structure, characteristic grasp of a habitation space place is important. The acoustic propagation model in consideration of the indoor characteristic was created, and the attenuation ratio and the control effect by difference of the reverberation characteristic were verified from a basic experiment and numerical analysis. This model was applied to acoustic field control technology, and the cause that the control effect falls in habitation space was considered. The control rule which prevents an effect fall under reverberation was proposed, and it verified that this technique was effective.

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In recent years, with the never ending progress in technology related to audio visual equipments and PC, etc., there is an increasing trends of using the reproduction sound of contents such as music and speech even for household purposes. Since all the phenomena occurring in nature need to be considered in relative frame of reference, a pleasant and enjoyable sound to the listener may appear as a noise to the people (non-listener) around the owner of sound player. Therefore, the aim of the present work is to develop a sound field control technology which confined the sound field to the listener only. In this paper, the authors propose a control technology to produce both the listening area the sound pressure is increased and the non-listening area the sound pressure is maintained. Based on the experiment and theoretical estimation the performance of the present technique is verified.

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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. This type of low frequcncy 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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In three-dimension acoustic field it is difficult to control in the whole room using active noise control (ANC) technique. Instead, around-head-control is investigated in this paper. By using around-head-control method, ail object person can get the noise reduction effect without controlling in the whole space, because it makes around the head quiet locally. Therefore, to realize around-head-control, it is necessary for a controller to follow the head movement. However, there is a problem that the control effect during the movement is worse, and the recovery of control effect after the movement is slow by conventional ANC. Against this problem, we propose the new method of improving the adaptation speed when an evaluation point moves. The algorithm can control by interpolating the secondary path of the Filtered-x Algorithm while moving. In the algorithm, the updating size appropriate to each coefficient of the adaptive filter scalculated by using a step size vector. The step size vector is calculated from the coefficient of adaptive filter before updating. The validity of the proposal method is shown by the numerical simulation.

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In this paper, an active noise barrier (ANB) using active noise control technique to improve the performance of passive noise barrier is proposed. The ANB consists of several feedback control units and a feedforward control unit. The feedback controller provides active noise insulation, and the feedforward controller whose reference signal is synthesized in the feedback controller cancels noise at its error microphone. A preliminary identification step is required in which the effective characteristic of controller to minimize noise at control point is modeled as a FIR filter. Once the preliminary identification step is completed, the error microphone for feedforward control is removed during control. As a result of computer simulation, the ANB is more effective for noise insulation than use of feedback control units or single feedforward control unit in low frequency.

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The main objective of this study is to apply active noise cancellation technique to the duct fan. In the acoustic field of duct fan, the rotating acoustic modes are generated due to the interaction of stators and rotating blades. To achieve the essential elimination of dominant acoustic mode inside the duct. the accurate acoustic mode decomposition and the reproduction of anti-noise are both required. We build a real-time acoustic mode decomposition system with an array of microphones circumferentially mounted on the duct surface. The filtered-x LMS algorithm in the frequency domain form is developed with applying the result of mode decomposition as an e汀or signal in order to achieve the elimination of specific acoustic mode. Array of loudspeakers are equipped circumferentially onto the duct to generate "anti-noise" signal.A large noise reduction and rapid convergence with this method have been shown by the results.

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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 dat a. Secondly, the simulation results of acoustic analysis were verified by compared with the measured results. The simulation results agree with the measured results except some frequency ranges.

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One of the authors has developed a technique to measure the transient vibration on unstable structure, for example, paper, film and so on, by using sound pressure measurement at near field. In this papeらthe theory of point sound source is studied to be constructed in order to verify the technique. The technique is discussed by using the wood speaker which vibration responses can be directly measured by accelerometcrs on the speaker unit and which sound pressure is measured by microphones near the speaker unit. And experiment that used two dimension of structure to develop the theory of point sound source was tried. As a result, it was understood that the theory consisted at time when the position of the microphone was 5mm.

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The present paper describes the numerical analysis of the radiated sound field generated by vibration of laminated flat elastic plates in a small enclosure with rigid wall. We try to apply a 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 frequency response changes depend on the opening shape and vibration characteristics of stiffer plate. Since the experimental results show the same tendency as the numerical results, the validity of the numerical simulation using the FDTD method in this paper is confirmed.

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The noise and vibration control are the one of important issues. A sound insulation cover which covers a sound source is very useful for the noise reduction. The purpose of the present study is to investigate the acoustic characteristic of a sound insulation cover using acoustic/structure coupled analysis. To verify the numerical results, experimental measurement of sound pressure level was also carried out. It is clearly that sound pressure distributions inside and outside cover changed obviously according to the input frequency of a sound source. Several downward peaks of the sound insulation were observed and these peaks were depended on the natural frequency of the insulation cover. Numerical and eχperimental results were consistent qualitatively.

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In the paper, we propose a concentrated mass model to perform a two-dimensional acoustic analysis. This model consists of masses, connecting springs, connecting dampers, and base support dampers. The characteristic of connecting spring is derived from the condition of adiabatic change of air, and the equivalent mass and the equivalent damping coefficient of the base support damper are derived from the shear stress from the wall. To confirm the validity of the proposed model, the numerical results obtained by the concentrated mass model are compared with the theoretical value of a traveling wave, and with the theoretical value of the natural frequency. A11 numerical computational results agree veiy well with the theoretical values. Therefore, it is concluded that the proposed model is valid for the two-dimensional acoustic analysis.

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The optimized individual sound environment is necessary to more than one people in the Smart Sound Space having the ability to support the activities of the people. In this research, multi-zone sound field control using multi-speaker in interior space of the car is researched. For the purpose of the evaluation for the multi-zone, the physiological reaction is evaluated using oxy-Hb by the optical topography (NIRS) and LF/HF based on RRJ of the electrocardiogram in order to achieve the separation of the space based on objective assessment. The effect for the SPL change of the music and car-navigation voice under the cruise noise is observed by the 12 subjects.

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At the Great East Japan Earthquake May 11th 2011 , many peoples died by the TSUNAMI. We think that one of cause of it is on inadvisability of evacuation guidance. We are feeling the necessity for an effective evacuation guidance sound which all peoples feel necessity to escape immediately if hear it. Therefore we try to evaluate sounds to feel necessity to escape. Sin wave, Triangle wave, Saw-tooth wave, Square wave and Siren wave were evaluated as test sound. all test sound sweep 2 octave or 4 octave. The n・equency and band width were evaluated too. Scores of 'feeling of escape' of triangle wave and square wave were higher the other wave forms. Wide frequency band made to feel necessity of escape strong.

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Recently, customer requirements for vehicle interior comfort have been increased and it becomes necessary not only to reduce sound level of interior noise but also to improve sound quality. During high speed cruising, aerodynamic noise becomes dominant in the interior noise. Especially, fluctuating aerodynamic noise which is generated by natural wind causes poor sound quality. To study vehicle geometry which reduces fluctuating aerodynamic noise at the early stage of vehicle development, prediction method is needed. This paper describes prediction method which is combined CFD (Computational Fluid Dynamics for transient pressure fluctuation and SEA (Statistical Energy Analysis) for structural acoustic to realize fluctuating aerodynamic noise in the cabin. It IS shown that interior fluctuating aerodynamic noise is different by a difference in geometry such as side view mirror and A-pillar corner.

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The condition based maintenance for pump system has been executed to enhance reliability and to optimize maintenance cost by introducing RCM (Reliability Centered Maintenance) as a part of the asset management of Sendai Sewage Works. Maintenance cycle of the equipment mostly depends on its bearing's lifecycle. Conditions of bearing parts of pumps are monitored under operation by vibration and acoustic emission measurement because the measured data provide information about maintenance criteria. Possibility of damaging on bearing parts can be suspected according to acoustic emission measurement. After measurement, individual inspection on bearing parts which are removed from shaft is carried out at overhaul. As a result, such failures on bearing parts as scratches and defects have become more apparent. Daily inspection with vibration measurement and trend monitoring by vibration and acoustic emission measurement are applied as strategic maintenance instead of existing time based maintenance to pump system.

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A new light sound insulation structure was proposed in the previous paper, which was constructed with pressurized light inflated membrane bound by hard wire nets. The sound insulation mechanism of that structure is examined in this paper by some parameter tests and simulations. As the results, the following facts are proved. This structure 18 simulated by a parallel impedance model of the membranes and wire nets. In the low frequency region, the rigidity of the pressurized wire nets with membrane dominates the sound insulation performance and the rigidity of the small piece of membrane bounded by the wire nets dominates it in the higher frequency region.

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Noise Insulator for Rail Joint termed as NIRJ has been developed by RTRI. Noise reduction effect of NIRJ was evaluated by verification test conducted for glued-insulated joint in commercial line. On the test, in addition to evaluation of noise reduction effect of NIRJ, comparison of noise of ordinary rail with rail joint, and evaluation of noise reduction effect due to rail grinding were also conducted. Consequently, we confirmed t!lat the countermeasure for noise at trailer passage was necessary as well as countermeasure n)r noise at motorcar passage at rail joint, since the noise level is not so much of between trailer passage and motorcar passage at rail joint. Although noise level at a rail joint is higher than that at away from rail joints by approximately 3dB, noise level was reduced approximately 2dB by, rail grinding. In addition, by installation of NIRJ, the noise level at a rail joint was reduced to only l〜2dB higher than that at away from rail joints.

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Double leaf sound insulating wall is widely applied to cabins of air plane, high speed train and cars,because transmission loss is larger nevertheless the weight is light. But transmission loss of double leaf wall is decreased at the resonances of panels and air space between them. We experimented the improvement of transmission loss by using the perforated panel set in the air space and the dynamic vibration absorber set on the sound radiated surface of the wall. We found that both devices worked well even if we set perforated panel and dynamic vibration absorber at once, and that frequency region in which transmission loss was increased became wider. And we found that computated results which were derived by using FEM for analysis as vibro-acoustic problems were consistent with experimental results.

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Several studies have been conducted by measurements and theoretical models on developing an understanding of the wheel/rail noise, which significantly influences wayside noise in the frequency range from 250 Hz to 4 kHz. Few studies reported that when a train runs on a gentle curve, the wheel/rail noise is greater by more than 5dB than the usual rolling noise, and this is closely related to the occurrence of the noise at higher frequencies above 10 kHz. This paper comments with an attempt to investigate the vibration properties of a rail at high frequencies. These properties are experimentally examined using a shaker. It is confirmed that free wave propagation occurs in the rail at higher frequencies above 10 kHz owing to a low decay rate.

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Many studies to develop understanding of rolling noise, which has great influence on wayside noise in the frequency range 250 to 4000 Hz, have been carried out by measurements and theoretical models widely. In some studies, when a train runs on a gentle curved track, wheel/rail noise is greater than usual rolling noise by more than 5 dB, and this is closely related to the occurrence of the noise at higher frequencies above 10 kHz. In this paper, an attempt is made to investigate the mechanism of the noise through running measurements. It is found that the wheels on the outside rail of the curve are the most important source during a train pass-by and the predominant component is the outside rail after a train has passed.

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In this study, effect of tangential blowing through slits opened on the surface of a cylinder is investigated, in order to reduce aerodynamic noise from the cylinder placed in the mainstream of a wind tunnel. When blow-ing through slits is faster than mainstream of the wind tunnel, the intense narrow-band noise radiated from the cylinder in case of no blowing is attenuated significantly. At this time, reverse-flow region behind the model disappears and vortices released alternately from each side o the cylinder become small and weak, which seems to cause reduction of aerodynamic noise. Further increase of blowing does not bring further attenuation of the narrow-band noise, but generates rather loud noise in high-frequency.

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This paper describes the experimental investigation on the acoustic absorption caused by interaction of sound waves with fine-scale jets. The authors carried out the experiments on two types of perforated plates: one has the straight channel, the other the tapered. The experimental results showed that the absorption was enhanced by the fine-scale jets through the perforated plate, compared with the non-flow case. The fine-scale jets through the tapered channel provided a better absorption coefficient over a wide frequency range.

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Reduction of aerodynamic noise emitted from a panhead is a very important subject for environmental preservation and speed-up of Shinkansen trains. In the present study, control of flow around pantograph panhead using a plasma actuator was studied by using large eddy simulation (LES). The results of numerical simulation suggest two effects of plasma actuator. When a body force generated by plasma actuator is small, interference between the shear layer and the induced flow from plasma actuator suppresses generation of von Karman vortices. On the other hand, when a body force is large, the shear layers are drawn to the panhead surface and the separation from the panhead is almost prevented. By these effects, the plasma actuator can control shear layer and reduce aerodynamic noise from the panhead.

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Control of flow by use of synthetic jet actuators have been found to be useful for the reduction of aerodynamic noise radiated from pantograph head on high speed train. However, there was a problem that actuation noise from synthetic jet actuators occurs. This study describes the reduction method of actuation noise from synthetic jet actuators by operation in opposite phase of neighboring actuators set inside fun-scale panhead model. Noise measurement results indicate that in case of 'opposite phase', not only can aeolian tone be reduced as drastically as in case of 'in phase' but also actuation noise can be reduced significantly.

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In the present paper, the effect of solid fin around a bare tube on the aerodynamic sound was experimentally investigated. This fin was mounted spirally around a bare tube and had the same geometry as those actually used in boiler tubes. We measured the sound pressure level of the aerodynamic noise generated from finned tubes with various fin pitches. An Aeolian tone induced by Karman vortex shedding was observed in the case of a finned tube. A decrease in the pitch of the fin effectively caused an increase in the equivalent diameter, which acted as the characteristic length of a cylinder with fin. When the pitch of the fins decreased, the peak level of the sound pressure spectrum decreased. However, the peak level at the fin pitch ratio of 0.11 became larger than the case of bare tube.

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When a train enters a tunnel at high speed, an impulsive pressure wave, called a micro-pressure wave, is radiated from a tunnel exit portal. Because it is one of the important wayside environmental problems in high-speed railways, many studies about its countermeasures have been conducted. The principal countermeasure applied to the Shinkansen on the ground side is a tunnel entrance hood. In this paper, a new counte°leasure to install a tunnel exit hood to reduce the micro-pressure wave has been proposed. The tunnel exit hood has an inside partition which divides the inside of the hood into two parts in the vicinity of its mouth with the end of one part closed. It has been shown that the tunnel exit hood can be effective in reducing the magnitude of the micro-pressure wave.

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Our flnaltarget of this study is developing a simulation technique for predicting the pressure pulsation inside automotive exhausting system. In the simulation technique the pulsations of pressure and flow are assumed to be governed by one-dimensional wave equation and the method of characteristic is used. This paper discusses the verification of the built model under the condition that the gas is air and the temperature through the exhaust system is constant by using pneumatic blower. The exhaust system is modeled by the combination of three fundamental elements (pipe, volume and oriffice). As a result, it is shown that our modeling of the pipe system has good accuracy with the measured pressure.

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It is hardly possible to install extremely high soundproof walls without reinforcing the viaduct drastically because the higher the soundproof wall IS, the greater the load and moment by wind becomes. Therefore, we have developed a new type of soundproof system. The developed system composes of transparent soundproof plate and frames supporting the plate. In this system, a rotary axis, and a11 support the soundproof plate or a part of three sides of it except the rotary axis are fixed by magnetic attractive force in ordinary state. 0n the contrary, when the wind load amounts to a limit of maintaining the safety of a viaduct, the plate opens and the wind load is reduced sufficiently. We have executed a load test, wind tunnel experiment and soundproof property test to verify the mechanism and property of the system with specimen in practical scale.

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A remarkable vibration at the bearing housing of electric motor had been detected on the large cooling tower in some chemical plant when the cooling tower had been in the trial run. This motor drove the cooling fan with long drive shaft and this fan was an axial flow fan which diameter was 5m. The dominant frequency of the vibration was 17.5Hz when the rotational speed had been some special condition and the vibration had not been extreme on the other rotational condition. The mechanism of this vibration trouble had been made clear. The dominant frequency of vibration was same as the blade passing frequency of the cooling fan and as the frequency of circumference natural vibration mode of the fan casing. The periodical velocity fluctuation in the wake flow with fan blades excited the natural vibration of fan casing. And the base of motor with drive shaft were excited by the vibration of the fan casing as the base connected to the bottom of fan casing. But the bending vibration of the long drive shaft was not the cause of the vibration of motor and bearing.Finally, the stiffness of fan casing was changed to strong for controlling the natural vibration.

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Recently, the need for noise reduction of high pressure fuel pump has been increasing due to rising environmental consciousness and improving comfort. Based on our acoustic investigation under idling condition, we identified that the solenoid noise and the compression noise are dominant on high pressure fuel pump. We have investigated the acoustic improvement technique of the solenoid noise for high pressure fuel pump and came to a conclusion that the solenoid noise can be reduced can be redused ca. 3dB by using optimization of control parameters and a reduced spring force. In this paper, we explain the concept of noise reduction, the control method and the extent of acoustic improvement.

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It is important for home appliances to reduce their noise. Many motors are used in these appliances and their vibration sometimes cause noise. In this paper, we investigate the noise of the exhaust fan and reduce it. When the electromagnetic exciting force and the mechanical system vibrate sympathetically, vibration and noise level rise. In order to lower their level, we investigated the characteristic of the electromagnetic exciting force of the motor and vibrational mode of the mechanical system. As a result, we modified the shape of the fan slightly and achieved 10dB of noise reduction.

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In order to predict interior noise caused by aerodynamic forces, wind tunnel experiment and numerical simulation were conducted. The experimental results showed that the contribution of acoustic excitation on the interior noise of the car is larger than that of the fluid dynamics. The new method based on FDTD for the simulation of the aerodynamic noise and interior noises were proposed. The numerical results showed the proposed method is effective to simulate the interior noise of automobiles.

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Removal of cesium, cobalt, or strontium ion from the aqueous solution containing each metal ion only using microorganism was examined. Arthrobacter nicotianae which had a high ability to remove cationic metal ion was used for the removal of each metal. The removal of cesium. cobalt, or strontium using A. nicotianae cells was affected by the solution pH, concentration of metal ion, and cell amount. The effects of above mentioned factors on the removal of each metal and time course of strontium from the solution containing each metal only using A.nicotianae cells were reported in this paper.

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Recovery of rare metals and base metals from electric waste (E-waste) would be of interest because of a sharp global-scale increase in commodity prices. In this study, a new material recycle process from waste electronic circuit boards using high frequency induction heating was proposed. Heating and separation examination was carried out using thin and nexible electronic circuit boards. Although it is difficult to heat up good electric conductor by induction heating, the temperature of these samples sufficiently increased and thermal decomposition of resin in these boards was confirmed. Separation between metal and resin film of these boards after induction. heating could be made easy. Moreover, optimal operating conditions of induction heating for the separation were clarified by several experiments.

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Coal and solid fuels derived from industrial wastes sometimes contain a small amount of mercury compounds. In conmbustion processes, gaseous elemental mercury passes through the stack and releases into the atmosphere. Mercury emissions in the combustion processes have been focused as one of upcoming air pollutants. In this work, it is the purpose to use wastes (sewage sludge, woody biomass and municipal waste) as an adsorbent of elemental mercury. We conducted mercury adsorption experiment used carbonized sewage sludge, carbonized biomass and carbonized municipal waste as adsorbents. As a result, the mercury adsorption ratio of carbonized municipal waste was the largest.

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To investigate the conversion of producer gas (CO+C02), the highly loaded and well-dispersed NiO/SBA-15 was prepared by a post synthesis method and a direct synthesis method. By the post synthesis method, the NiO particles were inserted into the SBA- 15 pores. The NiO/SBA-15 prepared by the post synthesis method exhibited high efficiency and sele,ctivity for methanation. The producer gas conversion for methanation was increased with increasing N10 loading. When the NiO loading exceeded 50 wt%, the ch4 selectivity was 100 % for CO_2 methanation. The highly loaded and well-dispersed NiO/SBA-15 was obtained for the first time by the direct synthesis method. By the direct method, the NiO particles were dispersed into the Si02 structure of SBA-15, unlike that prepared by the post synthesis method. The NiO/SBA-15 obtained by the direct synthesis method exhibited excellent efficiency, and selectivity for producer gas conversion to CO comparable to that obtained by the post synthesis method. The synthesis method affected the CO selectivity. The temperature and h2/co2 ratio played an important role in C02 conversion to CO, indicating that a high temperature and high h2/co2 ratio favored C02 conversion. The N10 loading did not affect the CO_2 conversion to CO. Although there was no difference in the CO selectivity when the NiO loading was increased at high temperature, it was influenced greatly by N10 loading at low temperature as a result of ch4 formation.

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JFE Engineering has developed the advanced stoker-type incineration system "JFE Hyper 21 Stoker System", which realizes low excess air combustion, minimization of environmental pollution and more effective use of energy. To improve the performance of this system, we have attempted to develop the numerical simulator to grasp the combustion behavior in the incinerator. In previous report, we selected the suitable reaction model and showed the calculation results of Three-dimensional domain of main combustion zone model. In this report, we describe the results of Three-dimensional domain of entire incinerator model and comparison between calculated value and measured value in actual plant.

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This paper describes ammonia dispersion was compared by two methods for improving the performance of selective non-catalytic reduction. One method is injecting ammonia with steam and the other is spraying ammonia water with compressed air.It was found that the method of injecting ammonia with steam is superior to the method of spraying ammonia water with compressed air on ammonia dispersion. In addition, higher steam pressure and larger nozzle diameter improve the ammonia dispersion. However, stronger steam injection may damage refractory material on the opposite wall.

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The Ecotopia Ikehara of Kurahama Sanitary Facilities Association, in Okinawa Prefecture is a fluidized-bed gasification and ash melting plant. The capacity of this system is 103 ton/day x 3 lines, 309 ton/day in total From June 2011 to February 2012, the third line was operated continuously in 226 days, and demonstrated combustion stability in k)w excess air with very tow emission of carboon monoxide. The most valuable result of low excess air combustion 18 k)w transfer rate of lead to slag in despite ofoxidant atmosphere. Therefore,slag from this plant kept meeting Japanese Industrial Standard fro slag material for road construction (JIS A 5032:2006) in this continuous operation. This continuous operation brought about an effect that low txiital consumption of fuel oil.

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A system which realizes improved power generating efficiency and fuel conversion/reduced landfill disposal of sewage sludge by cooperative utilization of energy between a waste incineration plant and a sewage plant was proposed. Verification of these effects using the case of a midsized city as a model confirmed that a large improvement in generating efficiency and large reduction in CO_2 emissions are possible.

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The purpose of this study is to design the biomass utilization system for different types of fuel production technologies and energy conversion technologies. The experimental study of energy conversion technologies of biomass energy have been done for a long time, and the modeling and evaluation methodologies of bioraass energy system such as life cycle assessment have been studied. However the system design methodology is still not established for different types of biomass resources and technologies. In this study, we have designed integrated biomass energy system for different types of technologies. The system consists of 6 processes; ultivation and Collection, Transportation, Preprocessing, Fuel Production, Energy Conversion, and Waste treatment. By using this model, we can analyze energy balance, environmental impact, economic impact, energy return on investment, CO_2 reduction cost, and net CO_2 emission factor ofbiomass energy

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The purpose of this study is to evaluate available woody biomass potential in Japan. Quantity of unused woody biomass is estimated and evaluate the feasible quantity within unused woody biomass by designing woody biomass utilization system. Target area is Tohoku region in Japan, and target esources are factory waste and construction waste, which are industrial waste, thinning branches and forest wood residues, which are forestry waste, fruit tree branches, which are agricultural waste. Cost, C02 emission, and energy balance of the system is evaluated to uncover availability of woody biomass. In this study, actual available quantity of woody biomass is evaluated by designing biomass utilization system using co-firing technology with coal. ln addition, effect of setting forest road to biomass potential is evaluated

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The purpose of the study is to design a woody biomass supply system for coal co-firing, and to evaluate the system considering the three dimensions of energy, economic, and environmental impact. Attention to co-firing of woody biomass in coal-fired power plants as a method to reduce CO_2 emissions has been growing. It is important to design the supply system considering the dimensions energy balance, economic efficiency, and environmental impact, since the potential of woody biomass resources differ in each region. The study targets five types of woody biomass; forest wood residues, forest thinnings, sawmill wood residues, construction wastes and pruned branches of finit trees. The system contains of collecting of biomass, transporting raw materials, producing wood fuels, transporting wood fuels, and coal co-firing. The study evaluates 6 cases which differ in wood fuel production location and the type of wood fuel produced. The results show that pellets produced at the resource generation points have the lowest amount of energy onsumption, wood fuel supply cost and CO_2 emissions.

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