This study aims to develop a theoretical foundation for considering architecture as knowledge commons. The findings of commons research were applied by setting research questions on 1) how architecture can be considered as knowledge commons and 2) what kind of architecture can be defined as knowledge commons. The achievement of this study is to present an analytical framework called the AKC (Architecture Knowledge Commons) framework, which is an application of the IAD framework, the core methodology of commons research, to architecture, and to identify the theoretical conditions for considering architecture as knowledge commons.

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The present study has been carried out to investigate the simultaneous behavior of combustion of 'pulverized coal ' (described as '' afterwards in this paper), and of reduction of fine iron ore using a laboratory scale tube furnace.
Experimental results show that apparent combustion rate of is not affected by the ore/ mole ratio simultaneously injected. The reaction rate constant of was not changed with changing wustite/ injection ratio. On the other hand, the rate constant of increased proportionally with an increase of hematite/ injection ratio. This implies that hematite behaves as an effective oxygen source for combustion.
The main reduction mechanism of fine wustite injected is found to be the direct reduction between molten wustite and unburnt carbon. Similarly, for the case of fine hematites, the direct reduction between molten magnetite thermally decomposed from hematite and solid carbon entrained into the droplet is the main reduction mechanism.
It was observed that the reduction degree of fine iron oxides mainly depends on the specific combustion heat (kJ/g-ore) which is defined as the ratio of combustion heat of to the feeding rate of fine iron oxide.

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Briquettes for heating or cooking are often made by pressing a blend of various chars. Desirable briquette properties include ease of ignition, minimal odors, high heat and long burning time. Lignite contributes high heat and long burning but is often mixed with wood to improve the ease of ignition. A thermogravimetric procedure was developed to measure the ignition proper ties of various lignite and wood samples. Chars were collected at several points in the charring process or produced in the laboratory. Charring temper ature, time and length of aging of the in air were important factors in the final ignition properties. ignition temperature correlated well with the hydrogen content of the .

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In this study, a theoretical model was constructed for the

gasification process, including pore structure sub-model, inorganic element catalytic/inhibitory index factor sub-model and structure function sub-model, combined with the simple gas-solid collision theory to predict the gasification reaction rate. In the experimental part, six typical biomass samples were selected and placed on thermogravimetric analyzer to test the gasification rate. The model calculated values were in good agreement with the experimental results, indicating the reliability of the model.

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Injection of plastics into blast furnaces as an alternative reducing agent has been carried out for the purpose of mitigation of carbon dioxide emissions. Several studies on the pyrolysis of plastic particles have been reported, however flow behavior of plastic particles or unburnt in actual blast furnace is not clear.
In this study, hotmodel experiments and thermogravimetry analysis were conducted for the modeling of gasification and combustion behavior of plastic particles, then flow behavior of plastic particle and unburnt in a blast furnace was calculated by numerical simulation. According to the observation results of combustion experiment, volatile matter of plastics seems to be evolved at the surface of the particles. Regarding reaction of derived from plastics, thermogravimetry analysis showed that rate of gasification of unburnt depended on the rate of heating. Gasification rate in the case of rapid heating condition tended to increase.
As the results of numerical simulations, initial diameter of plastics and diameter determined the flow behavior in the blast furnace. When relatively small plastic was injected or diameter of unburnt was small, unburnt went upward along with gas flow and most of it might be consumed at the cohesive zone. On the other hand, when relatively coarse plastics was injected and diameter of unburnt was relatively coarse, it was suggested that unburnt accumulated around the deadman.
Therefore, it is considered that fine plastics injection is desirable for the stable operation of blast furnace.

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Decrease of carbon dioxide emission is a serious subject in the steel works. Utilization of biomass as a carbon-neutral agent is an attractive one for iron ore sintering. Sinter pot tests were carried out with using raw biomass and biomass carbonized . It is not good on yield and exhaust gas that raw biomass is used directly as carbon material for iron ore sintering. While, it is good on the productivity and the exhaust gas (NOx, SOx, dust, dioxins) that biomass carbonized is used as carbon material. With using biomass for the sintering, it is necessary to optimize operation (size control and moisture control of the biomass ), because combustion rate of the biomass is too high. Biomass carbonized is evaluated on sinter yield as similar as anthracite or coke. The biomass is effective to decrease CO₂, NOx, SOx, dust etc. emission in sinter exhaust gas.

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This paper presents a technology to utilize bio- and bio-tar from the pyrolysis of oil palm empty fruit bunch, EFB. In this study, tar vapor from pyrolysis of EFB was infiltrated within porous bio- and carbon deposition occurred on the pore surface by chemical vapor infiltration process. For preparation, EFB particles were made into pellets. In the first part of experiments, porous bio- pellets were produced by slowly heating the EFB pellets in a tube furnace in argon atmosphere to terminal temperatures of 500–800°C. In the second part, the porous bio- pellets were used as precursor for tar decomposition process to deposit carbon within the bio- pores. Tar vapor was obtained from the pyrolysis of EFB at 400–500°C at a fast heating rate for tar decomposition to occur. The purpose of this research is to investigate the amount of carbon deposited within bio- by this tar carbonization process as compared to carbon contents of metallurgical coke. We showed how EFB bio- was used as the tar filter and in the process to produce carbon-infiltrated bio-, a useful renewable energy source for ironmaking process.

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Carbonization behavior of biomass in the rapid carbonization/pulverized process using heat storage materials was experimentally examined. Biomass samples were charged into a rotary kiln-type electric furnace with stainless balls. Obtained biomass chars were evaluated by means of gasification test in CO₂ atmosphere using a thermal gravimetry. The

was classified into two type, “fine” and “coarse”, by particle size.

“Coarse”

contracted with increasing holding temperature. Crashing of biomass was observed at the holding temperatures over 600°C and fine was formed. Melted structure was observed on the surface of “coarse” indicating rapid heating. Yields of the total are decreased with increasing holding temperature due to vaporization of volatile matters like tar. On the other hand, the yield of “fine” is increased with increasing rotation speed when carbonization reaction sufficiently proceeded.

The

obtained by the present carbonization experiment at between 600 and 800°C for 10 min showed similar gasification property with CO₂ to that prepared by normal carbonization at 800°C for 1 h.

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Injection of plastics into blast furnaces as an alternative reducing agent has been carried out for the purpose of mitigation of carbon dioxide emissions. Several studies on the pyrolysis of plastic particles have been reported, however flow behavior of plastic particles or unburnt in actual blast furnace is not clear.
In this study, hotmodel experiments and thermogravimetry analysis were conducted for the modeling of gasification behavior of plastic particles, then flow behavior of plastic particle and unburnt in a blast furnace was calculated by numerical simulation. According to the observation results of gasification experiment, volatile matter of plastics seems to be evolved at the surface of the particles. Regarding reaction of derived from plastics, thermogravimetry analysis showed that rate of gasification of unburnt depended on the rate of heating. Gasification rate in the case of rapid heating condition tended to increase.
As the results of numerical simulations, initial diameter of plastics and diameter determined the flow behavior in the blast furnace. When relatively small plastic was injected or diameter of unburnt was small, unburnt went upward along with gas flow and most of it might be consumed at the cohesive zone. On the other hand, when relatively coarse plastics was injected and diameter of unburnt was relatively coarse, it was suggested that unburnt accumulated around the deadman.
Therefore, it is considered that fine plastics injection is desirable for the stable operation of blast furnace.

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To clarify the gasification and consumption behavior of unburnt ascending in the coke packed bed in the lower part of the blast furnace, reaction-consumption model has been newly developed considering the average residence time and co-gasification with coke particles. The chemical reaction rate constant has been determined based on the high temperature experiments on the injection into the coke packed bed.
From the analyses using this model, the following results were obtained.
( 1 ) The mean ascending velocity of particles with the diameter of 20 μm was approximately 0.3 m/s, and it was smaller than the actual gas velocity by one order of magnitude, suggesting the particles had fairly long residence time in the blast furnace.
( 2 ) The consumption rate of became lower with the increase in the solid-gas loading ratio. This was considered to be caused by the higher ascending velocity which resulted from the successive renewal of stagnant particles in the packed bed by supplied particles.
( 3 ) According to the examination of consumption behavior along the blast furnace height, discharge rate from the top of the thermal reserve zone could be reduced considerably by decreasing exhaust rate from the raceway. This phenomenon resulted from the increase in the consumption rate throughout the height, due to the decrease in the solid-gas loading ratio. Therefore, to suppress the exhaustion from the top, it was necessary to improve the combustion efficiency in the raceway at higher injection rate of pulverized coal.

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The purpose of this study is to clarify the relationship among the reactivity of coal , the carbonaceous structural change, and the ash behavior. The steam gasification of various coal was carried out in a fixed-bed reactor. After the gasification, the reacted was analyzed by LRS (Laser Raman Spectroscope), and SEM/EDX (Scanning Electron Microscope, Energy Dispersive X-ray Spectroscopy). In order to evaluate the progress of carbonaceous graphitization, we observed I_D/I_V ratio that was one of the Raman parameters. As a result, graphitization of coal was equally observed under every condition as the increasing of conversion rate. So we estimated that the progress of graphitization would be caused with following reason. Disordered carbon structure, whose reactivity was higher, had been gasified alternatively, consequently the ratio of carbon that had graphitic structure increased relatively.Then in order to clarify the ash behavior affecting the reactivity, characterizations of each was carried out using SEM/EDX. From the results of observing SEM image and EDX-mapping, we found the different behavior of elements and novel parallel analysis between EDX-mapping and LRS-mapping was very effective for the comprehensive evaluation of ash behavior and carbonaceous structure. As the gasification reaction, the reactivity of was partially decreased, because the surface of carbon had been covered with certain elements such as Si, and reaction gas could not contact with the carbon.

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The reaction rates of Bintyo , Bamboo , activated carbon, coke, graphite and glassy carbon with pure CO₂ have been obtained by thermo gravimetric method. After the reaction, N₂ was introduced to the reaction tube to obtain the amount of adsorbed CO on the active reaction sites. The specific surface area after the reaction was measured by BET method. The results are summarized as follows:
The reaction rate per unit mass were in the order of Bintyo _??_Bamboo _??_activated carbon>graphite_??_coke>glassy carbon. The difference between the maximum and minimum were two orders of magnitude. The activation energy was 180 to 220 kJ/mol. The reaction rate per unit area of graphite, however, was an order of magnitude higher than those of Bintyo and Bamboo . The estimated amount of adsorbed CO was positively correlated to the reaction rate. The reaction rate constant which is independent from surface area was obtained using the reaction rate and the amount of CO adsorption, respectively per unit area. They are ranged in the order of 10^-4 to 10^-3 1/s. The differences among Bintyo , Bamboo and graphite became smaller. The enthalpy of CO adsorption was estimated as about 230 kJ/mol for Bintyo and Bamboo , and about 280 kJ/mol for graphite.

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In order to find its feasibility as blast furnace coke feedstock, non-metallurgical coal was compared with metallurgical coal in terms of reactivity and degradation during CO₂ gasification reaction, with emphasis on the difference between the pore structure of coke and that of . The following results were obtained:
(1) The higher reactivity of non-metallurgical coal is due to the fact that their coal rank is lower.
(2) Though the pore structure of metallurgical coke is composed mainly of macropores, pore walls of are either abundant in micropores when the rank is low, or practically nil in any size when the rank is relatively high.
(3) Open macropores characterize the pore structure of coke, while has a considerable number of closed pores.
(4) The deterioration of the structural strength of coke becomes greater than that of as gasification reaction proceeds.

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Using a drop tube furnace, samples were prepared from coals of different ranks, under conditions similar to those prevailing during pulverized coal injection into the blast furnace. The chemical structure of resultant chars was determined by quantitative X-ray diffraction analysis (QXRDA) and high-resolution transmission electron microscopy (HRTEM), and investigated as a function of pyrolysis temperature, heating rate and coal type. Among the parameters examined, pyrolysis temperature was the key factor influencing chemical structure. obtained at higher temperature is generally more ordered, with the distinctive peaks becoming sharper and the background intensity becoming lower. Heating rate is another important factor affecting chemical structure. is more ordered at lower heating rate due to the longer residence time. Although considerable differences were still observed in the chemical structure of chars prepared from coals of different ranks, it is clear that such differences are reduced after coal pyrolysis. structural evolution during post-pyrolysis and combustion was also investigated. The importance and potential applications of this work to the blast furnace PCI operation have been outlined.

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A particle gasification model applying the discrete approach has been developed to predict the effect of the particle structure (size, porosity and shape) and the reaction temperature on the reaction behavior. In this model, it was assumed that the shape of a particle before the reaction was a three-dimensional cube. A large number of small lattices arranged randomly in the cube and were classified into , ash and macropore depending on the 's proximate analysis data. In the reaction process, one-dimensional steady state diffusion of CO₂ was considered in the cylinders. It was assumed that CO₂ diffused through a large number of the cylinders, which represented micropores inside the particle and reacted to the wall of the cylinders. The dependence of the reaction rate on the temperature was analyzed by changing the size, porosity and shape. It is suggested that the pore diffusion behavior of CO₂ is influenced by the particle structure change. This is because the reaction rate is determined by the relationship between the chemical reaction rate and the diffusion rate. Therefore, CO₂ diffusion distance influenced by the particle size, porosity or shape, which is one of the major factors to determine the diffusion rate, remarkably contributes to control the transition temperature between chemical reaction rate controlling regime and pore diffusion rate controlling one. The uniform and peripheral reaction in the particle occurred depending on the reaction temperature. Furthermore, the reaction also occurred on the internal void surface of the particle at the high porosity, while the reaction only occurred on the external surface of the particle at the low porosity. The reaction temperature and porosity influenced the reaction position in the particle, so that the fragmentation behavior was different owing to the porosity and the reacting conditions.

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The paper presents the on-going research in accounting for heterogeneous nature of organic matter in pulverised coal. This is achieved by using the information from automated reflectogram technique developed at CSIRO Australia. The technique is seen as providing opportunities for characterizing coal in a way which, for the first time, will allow the heterogeneous nature of coal to be related to reactivity, ash formed and fine ash generation. All these aspects of coal utilization are related with character. The aim of the research is, therefore, to correlate the character to the reflectance of an individual coal particle. The coal is considered as a mixture of particles of different character in terms of chemical and physical properties. In the present work, the reflectance is considered as the main characterizing parameter for the organic matter in coal. All the bulk properties of coal or can be obtained from the summation of the properties of individual particles. For example, each individual coal particle devolatilises to a different extent resulting in a distinct particle. The properties of these particles vary monotonously with reflectance. A correlation was obtained for volatile matter as a function of reflectance in such a way that the volatile mater could be obtained from the reflectogram analysis using this relationship. This approach is extended to character. was produced from several coal samples and maceral concentrates in a drop tube furnace at 1400C. The porosity and average thickness of the particles were estimated from image analysis. Coal particles with low reflectance are expected to result in porous and thin-shelled particles. The was observed qualitatively in these samples. A relationship between reflectivity/reflectance of coal particles and the porosity of the resulting particles is obtained from regression analysis. This relationship is very important in modeling combustion of particles and ash formation. The effect of morphology on burnout is demonstrate using CBK7,a combustion model. The implication on ash formation is also discussed.

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