Hyper-Coal (HPC) is produced by extracting a coal in 2-ring aromatic solvent and separating insoluble component (Residual-Coal:RC) from soluble component by gravity settling separation. HPC has excellent thermoplasticity and large potential for coke additive to make a strong coke. The yield of HPC depends on the coal solubility. And the thermoplasticity performance of HPC depends on the separation efficiency of settling separation processes. Separation efficiency depends on the settling velocity of RC. So, it is important for HPC process not only to have a high solubility but also to perform a high settling velocity of RC. In this study, we focused on the effect of classification of coal particle size to obtain the efficient process performance. The classified particle groups were examined in the extraction and settling performance. It was shown that the each group of particle size has different behavior of dissolving. The fine particle group performed lower extraction yield due to the lower VM and the atomic H/C ratio characteristics. In addition its settling velocity was different with each particle size group. It was thought that the aggregation behavior depends on particle interactions.

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HyperCoals (ashless coal, HPC) can be produced from wide range of ranks of coals including low rank coals. Generally the coke strengths can be enhanced by adding HPC, and so utilizing HPC from low rank coals as caking materials is the goal of the current research. In this paper, ^1H-NMR and solid state ^<13>C-NMR measurements, and ultimate analysis were carried out to investigate the molecular structure of HPC prepared from low rank coals. The results suggested that the number of aromatic rings in a unit structure increased from 1 - 2 in original coals to 2 - 3 in the corresponding HPCs.

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Low rank coals are abundantly deposited and widely distributed, although they have not been used on a large scale except at the mining sites because of their high water content and oxygen content, and because of the high possibility of self-ignition when dewatered. Therefore, treatment for both dewatering low rank coals and suppressing their self-ignition tendency as well as increasing their heating value is essential. In this study, the possibility of the degradative solvent treatment, which treats coals in a non-polar solvent at 350℃, was examined as the method for self-ignition suppression, and the factors influencing self-ignition tendency was discussed.

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In recent decades carbon fibers have been used widely from various purposes. However, the practical utilization of carbon fiber is limited by its high price which comes from the high cost of its feedstock as well as manufacturing cost. We have proposed a degradative solvent extraction method to separate various low-rank coals and biomasses to several fractions under mild conditions. The low-molecular-weight fractions, obtained in around 30 % yield, can soften and melt completely at around 100℃. In this study, the low-molecular-weight fractions were proposed to be used as low-cost precursors for the carbon fiber. Preliminary experiments showed that the fractions can be easily spun to prepare spun fibers. The spun fibers were then extracted by cyclohexane to remove light compounds and stabilized by thermal treatment from 50℃ to 330℃ in air in 10 hours. The carbonization was performed at 1000℃ for 1 hour in N2. The diameter of the carbon fiber obtained was around 5 μm. Thus, the low-molecular-weight fractions obtained by low-rank coal or biomass extraction can be promising precursors of low cost carbon fiber.

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Nowadays, the oil agglomeration processes have been developed for reducing and making beneficial use of waste fine coal from the mechanic coal mining and coal cleaning. In this study, we recovered the carbonaceous contents from waste fine coal based on an oil agglomeration process using vegetable oil. At same time, we improved reduction ratio of pyrite sulfur which is usually difficult to be separated during the oil agglomeration process. In this study, we adjusted pH of the solution of oil agglomeration from neutrality to basic, in order to separate pyrite sulfur effectively from waste fine coal under the basic condition. During the high basic condition, pyrite sulfur reduction indicated high values since the pyrite surface became hydrophilic. As the results, the pyrite contents will not be recovered together with hydrophobic carbonaceous contents. However, coal cleaning efficiency, especially combustible matter recovery decreased under high basic solution.

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Brown coal has many oxygen-containing functional groups such as carboxyl groups and it is ion-exchangeable with metal. We examined Ni ion-exchange property of brown coal under several conditions.

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To broaden and lower the temperature window of the selective non catalytic reduction (SNCR) of nitric oxide (NO), the use of activated ammonia as the reduction agent was examined. A vacuum ultraviolet (VUV) or dielectric barrier discharge (DBD) was employed as the excitation source of molecular ammonia. The most of molecular ammonia was converted to molecular hydrogen at DBD reactor exit and VUV reactor exit. It considered that hydrogen was key chemical species for low temperature SNCR.

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Conversion characteristics of benzene and naphthalene as model tar compounds were studied with an atmospheric flow reactor at 1100-1400℃ in atmospheres that simulated the reducing section of two-stage entrained-flow coal gasifier in an air-blown or O_2/CO_2-blown mode. The experimental results showed that soot was one of the most important fates from the both aromatic hydrocarbons, but its yield decreased significantly as the inlet concentration of the aromatic hydrocarbons was lowered. It was also found that changing the mode from the air-blown to O_2/CO_2-blown suppressed the soot formation by promoting the reforming of the soot precursors when the inlet concentration of the aromatic hydrocarbons was below 8 g/Nm^3. Numerical calculation based on a detailed chemical kinetic model was performed for better understanding of the mechanism. The model predicted that the decrease of the inlet concentration leads to decrease of soot yield, and these trends were consistent with the experimental results. The model also indicated that hydroxyl radical (OH・) was a most important species for the pathways of decomposition of aromatics, and its concentration in O_2/CO_2-blown mode was higher than that in the air-blown mode. The model prediction was in agreement with the experimental result qualitatively.

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Ion-attachment mass spectrometry (IAMS) is a form of mass spectrometry that employs a "soft" form of ionization in which a cation is attached to the analyte molecule in a reactive collision. This technique is applicable to gases or any materials that can be vaporized. It uses a non-fragmenting non-conventional ionization mode, by attachment of a lithium or alkaline ion to the gas to be analyzed with a more traditional mass filter. In this study, we developed a prototype devise of the IAMS and conducted preliminary experiments toward an application of the IAMS to the real time monitoring of complex gas mixtures derived from coal thermochemical conversions. The model tar vapor which includes toluene, naphthalene, and 1-metyl-naphthalene, was measured by the IAMS and the results were compared with those obtained from the conventional electron impact (EI) ionization mode. We could successfully identify each molecule without any fragmentation peaks whereas the EI mode gave scattered mass signals due to fragmentation.

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Hyper-coal (HPC) Process produces ash free coal by thermal extraction and solvent de-ashing in the coal derived methylnaphthalene solvent. That process also produces insoluble coal, Residual coal (RC), in which ash is concentrated. HPC will be utilized for various usages such as coke additive, material for the electrode for aluminum smelting, electric double layer capacitors, feedstock for the catalytic gasification, and etc with understanding the superior characteristics. On the other hand, the characteristics of RC have not been understood enough yet. It is important to understand the characteristics of RC for realizing the commercialization of Hyper-coal Process. Concerning to it, behavior of low temperature oxidation of RC is examined in this study. High porosity characteristic of RC indicates higher risk of spontaneous combustion. It is needed to take preventive measures against spontaneous combustion, and to develop efficient utilize turning to advantage.

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The development of alternative platinum electrode is demanded because of the scarcity of Pt resources and its high cost. Non-Pt catalysts synthesized from hypercoal were investigated as cathode catalyst for polymer electrolyte fuel cell. Hypercoal is an ash-free brown coal produced by solvent de-ashing technology. Elements of iron, aluminum, potassium, magnesium, calcium and silicon were added to hypercoal separately and being followed by nitridation to incorporate nitrogen into the hypercoal carbon structure and to form a composite precursor of nitrogen, carbon and metal as a catalyst for oxygen reduction reaction. A three electrode activity measurement with rotating ring disk method was applied to measure the electrochemical activity of the prepared catalysts. The catalysts were characterized by X-ray photoelectron spectroscopy, XRD, Raman spectroscopy and TEM analyses. The addition of iron and aluminum simultaneously to hypercoal and the consequent nitridation upgraded the performance of hypercoal as a cathode catalyst for oxygen reduction reaction. The 2% (Al+Fe) doped hypercoal exhibits an onset potential of 0.79 V with a current density of 0.286 mA/cm^2 at 0.6 V. The characterization studies indicate that pyridinic type nitrogen is associated with the formation of active sites for oxygen reduction reaction. Raman analysis shows that the higher degree of graphitization along the edge sites in catalyst structure facilitates the oxygen reduction.

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It has been verified using a 5ton/day pilot unit that high moisture lignite can be dried rapidly and safely by hot air fluidized bed. The 60% moisture lignite was crushed to 2mm of average particle size, and it was dried to 20% moisture in 6 minutes by the hot air fluidized bed with 90℃ temperature. Dry lignite temperature was maintained below 60℃ to avoid spontaneous ignition. The safeness of this method has been confirmed since CO gas was not detected through all the tests and dry lignite was not exploded by static electricity level during ignition tests. Since this new dryer is compact, it can be installed in a boiler building and increase plant net efficiency by 2 points.

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Two common vegetal biomasses were extracted by liquefied dimethyl ether (DME). 86.9% and 81.3% of the water was removed from these high-moisture biomasses, this process also yields 5.8% and 6.2% organic extracts based on dry weight of samples. The properties of dewatered bio-solid such as proximate and elemental analysis, HHV, and oxygen reactivity were investigated. The results indicate that the dewatered bio-solid can be further exploited for energy production.

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The liquefied DME (dimethy ether) was used to dewater the frozen brown coal under a designed experimental condition at -20 ℃. By using this method, 98.1 wt. % of the initial water was removed from the frozen brown coal sample. The water forms in the tested brown coal sample at low temperature were studied using differential scanning calorimetry (DSC). It was found that the water existed in both ice and non-freezing forms at the temperature under frozen point indicating that both forms of water can be removed by DME at frigid condition.

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We have recently succeeded in recovering a large amount of low-molecular-weight compounds having a peak around 300 in molecular weight, which we call "Soluble", by treating of brown coals and/or biomass wastes in non-polar solvent such as 1-methylnaphthalene around 350℃. In this study co-processing of the Soluble and a low-grade iron ore which contains a large amount of FeO(OH) was proposed to produce both light oil and a raw material for iron making called "iron ore/carbon composite (IOC)". When the mixture of Soluble and the low-grade iron ore was heated up to 300℃, Soluble filled up the layered pore space of 0.8 nm wide which was formed by the dehydration of FeO(OH). When the mixture was further heated over 400℃, the Soluble in the pore space was catalytically cracked to produce light oil in high yield. The low-grade iron ore particles now consisting of Fe_2O_3 and containing high molecular-weight compounds, coke, in the pore space, was expected to be utilized as a high quality IOC.

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Catalytic cracking of petroleum residual oil using steam was examined with iron oxide catalysts containing zirconia and alumina. Heavy oil was oxidatively decomposed with the catalyst, producing light oil and CO2. The amount of light oil produced using the zirconia-supporting iron oxide catalyst is larger than that in case of the iron oxide catalyst. Alkene/alkane ratio of light oil decreased with increasing zirconia content. The results suggest that large amount of oxygen species react with heavy oil and large amounts of hydrogen species could be added to light hydrocarbons because zirconia promotes the generation of these species from steam.

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Hierarchical β and Y zeolite containing mesoporous silica-aluminas were prepared by one pot sol-gel method. β and Y zeolite crystal structures were maintained and hierarchical structures with microporous zeolite in center and mesoporous silica-alumina in outer shell were constructed. β zeolite containing catalysts exhibited much higher activity than Y zeolite containing ones. The presence of larger pores than in the zeolite and the control of the amount of acid sites effectively increased the selectivity for single- and multi-branched products which have higher octane numbers.

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Catalytic cracking of fat by hierarchical zeolite containing mesoporous silica-aluminas using a Curie point pyrolyzer were performed. Most of prepared catalysts showed the higher catalytic activity and selectivity for gasoline than single zeolite. The ratio of multi/single branch in the gasoline fraction reached more than 0.40, which was much larger than that of single zeolite. Catalysts prepared using a larger amount of malic acid developed the mesoporous structure and showed the higher olefin/paraffin ratio and RON compared with single zeolite and a catalyst with microporous structure.

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In this study, the combustion and pyrolysis of brown coal have been done. Combustion/pyrolysis rate had been investigated. As the result, the pyrolytic mass change varies according to the temperature in the furnace. The pyrolytic activation energy is divided into two stages. The activation energy is for 300〜400and 400〜800℃ are 5.2 and 39.8kJ/mol , respectively.

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It is important to use sub-bituminous coal at power stations in Japan. But sub-bituminous coal contains more than 20% moisture. This makes heat capacity for drying moisture becomes insufficient. So, we use less than 30% of blended ratio of sub-bituminous coal. There are two methods to increase the ratio of sub-bituminous coal. The one method is to lower the temperature of primary air, another method is to increase Air/Coal. So, we investigated the effects of air injectioncondition on NOx concentration at the exit of furnace and unburned carbon concentration in fry ash.

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Currently, it becomes increasingly necessary to decrease CO_2 emissions from fossil fuel combustion processes, because they are major contributors to the global warming. Oxy-fuel coal combustion has drawn attention as useful technique to achieve carbon dioxide capture and storage (CCS). This is the technique that enriches CO_2 in exhaust gas by the flue gas recirculation with additional pure O_2 to combustion atmosphere, which makes easy to capture and liquidize CO_2 downstream. However, there have been few reports about behaviors of various environmental pollutants in oxy-fuel coal combustion with the flue gas recirculation. In this study, we experimentally estimated effects of NO and N_2O recirculation with CO_2 by a drop tube furnace equipment. In addition, we simulated NO and N_2O formations under oxy-fuel coal combustion condition by elementary reaction analysis, and then we discussed mechanism for the formation of NOX.

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To improve prediction accuracy of late stage of char combustion, we propose and examine a new char combustion model (Radially-distributed model) which considers the variation of physical quantities in the radial direction of char particles. In addition, accurate and analytical boundary condition of particle's surface is approximately derived based on Stefan-Maxwell equation to apply the model to multicomponent system.

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Catalytic coal gasification using K_2CO_3 is an efficient way to gasify coal to FT suitable synthesis gas. This study reports the development of a continuous catalytic gasification process to gasify low rank coals and lignite to produce FT suitable synthesis gas in a single direct step using K_2CO_3 as a catalyst and a mixture of Steam and CO_2 as gasifying agent. A small 0.2 g/min laboratory scale continuous catalytic gasification unit was developed and experiments were carried out at 700 ・C with pure steam and a mixture of steam and CO_2. Synthesis gas with H_2/CO= 1, 2, and 3 was produced by changing the steam/CO_2 ratio of the gasifying agent. Experimentally observed gas composition was compared with the calculated values obtained by using thermodynamic equilibrium conditions and a good match was obtained.

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Steam gasification of Indonesian low-rank coal char was kinetically analyzed on the basis of Langmuir-Hinshelwood mechanism. According to the kinetic parameters determined by L-H mechanism, inhibition of gasification of char by hydrogen gas was substantial. The extent of gasification of char in a gasifier of our developed circulating fluidized bed gasification system was attempted to be described by using the kinetic parameters. The gas yield in the gasifier was successfully described by the kinetic parameters.

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A mini directly-heated reactor (mini-DHR) system was constructed and modified for accurate and handy gasification rate measurement under high temperature and high pressure in the presence of CO2, CO, H2O, and H2. The mini-HDR was made of Platinum tube of 3 mm I.D. and equipped with a VCR metal gasket connector to the reaction system; A quarts wool sample holder was used for the char (ca. 1 mg) packing in the reactor; A rapid heating combustion method using Q-Mass was used to determine the remaining carbon amount after the gasification of char. Systematic measurements of gasification rates were performed using the modified mini-DHR system and a gasification rate equation was established by combining the Langmuir-Hinshelwood model and the Random Pore model.

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Advanced IGCC (A-IGCC) was proposed with fluidized bed coal gasifier following the concept of exergy recuperation by steam reforming. A-IGCC has a capability of high efficient power generation with low grade coal such as sub-bituminous coal and lignite.

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The behavior of heat generation and oxygen absorption of the petroleum coke (PC) and coal was investigated. In the case of low rank coal, temperature raised remarkably by being exposed to air, whereas, the temperatures of the high rank coal and PC did not changed during the exposing test. Absorption and desorption behavior of PC was different from coal.

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The fate of the nitrogen and sulfur present in seven caking coals during pyrolysis has been studied with a flow-type fixed-bed quartz reactor to examine the effects of these heteroatoms on coal fluidity. The Gieseler maximum fluidity (MF) appears around 450℃ with all coals. The MF values range from 1.1 to 4.1 log(ddpm) and depend strongly on the type of coal. The evolution of HCN, NH_3, H_2S and tar-S starts after 350℃, whereas char-N, organic-S and FeS_2 decrease beyond 350℃. FeS_2 can readily be transformed to FeS and H_2S at 350-650℃. The evolution amounts of gaseous N- and S-containing species depend on the kind of coal. The MF value tends to increase with increasing total amount of HCN, NH_3 or H_2S evolved up to 450℃. Although the addition of 1 wt% aliphatic-N, inorganic-N or S-containing compounds to coal decreases coal fluidity, but polycyclic aromatic compounds increase the fluidity.

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The common method for obtaining iron from the iron ore is iron oxide reduction by using coke. Currently, coke production in Japan relies on importation of coal from foreign countries. Under this situation, the price of coal has been rising in recent years and further increase in price is expected in future. Therefore, in order to reduce the amount of coal consumption and in consideration of the future energy demand, it is important to consider some alternative coal resources. In this study, we target on the use of woody biomass as an alternative raw material for production of coke. We have co-carbonized mixtures of coal, wood biomass and lignin in various mixing ratio by using an electric furnace. To evaluate the suitability of the coke produced from woody biomass, we have examined its binding properties by using optical microscope.

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Wet flue gas desulfurization (FGD) wastewater discharged from coal combustion process contains some hazardous trace elements, such as selenium, boron, and mercury. The concentration of these hazardous trace elements was sometimes exceeded the effluent standard. In this study, the removal of Se(VI) from the simulated FGD waters by use of bioreduction and TiO_2 photocatalytic reduction were investigated. When the photocatalytic Se(VI) reduction systems were attempted for the simulated FGD waters, the reduction of Se(VI) to Se(0) precipitate was inhibited by the excess amount of co-existing anions, such as SO_4^<2->. When the removal of SO_4^<2-> from FGD water was carried out by use of a coagulation process, the removal efficiency of Se(VI) from the simulated FGD waters by the photoreduction process was improved.

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Relationship between the change of coke pore structures and caking additive size was investigated by image analyzing of coke cross section. When asphalt pitch (ASP) was pulverized to small size, they were dispersed on coke matrix and large pores which had formed from large ASP particle decreased. The low circularity pores which were mainly composed of connected pore or void around inert particle also decreased by pulverizing ASP. The reason was thought that the probability that gas generated from ASP combines each other decreased and the probability that adhesive force around inert particle was enhanced by ASP increase with wider dispersion.

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Solvent evaporation phenomena, which is involved in the solvent recovery process of the Coal-solvent extraction process (Hyper-coal [HPC] process), have been studied. It was indicated that HPC dissolution in the solvent mainly consisting of 1-mehylnaphthalene results in solvent boiling point elevation as the HPC influences solvent as solute. HPC molecules appear to be getting associated each other as the concentration of HPC increases. Moreover, the degree of boiling point elevation at atmospheric pressure can be estimated by thermodynamic calculation with a simple approximation.

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Effect of HPC on improving the maximum fluidity of coal blend containing steam coal and coke strength was investigated. New method to estimate the maximum fluidity of coal blend containing steam coal was developed. The coke strength from coal blend containing steam coal was recovered by controlling the maximum fluidity to the appropriate range.

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In our previous work we have developed a degradative solvent extraction method to obtain extracts with rather high yields from low-rank coals and biomass wastes at lower than 350℃ in N2. One of the extracts had molecular weight of around 300 and was expected to be liquefied easily under relatively mild conditions. In this work the extracts, obtained from lowrank coal and biomass wastes, were liquefied at lower than 400℃ under the H2 pressure of as low as 2 MPa (at room temperature). Their parent materials were also liquefied for comparison purpose. The results showed that the oil (hexane soluble excluding water) yields reached to higher than 60% at 400℃. Oxygen contents of the oils obtained from the extracts were much lower than those obtained from their parent materials. Furthermore, H_2 consumptions and CO_2 emissions of the extract liquefactions were rather lower than those of their parent material liquefactions. Thus, the combination of our proposed degradative solvent extraction method and liquefaction of the extract under mild condition may be a promising method for liquid fuel production from low-rank coals or biomass wastes.

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It has been developed a reliable methodology to be able to elucidate such thermal behaviors as thermo-plasticity, and carbonization of coal based on the dielectric property which can be directly reflected by the polar functionality of macromolecular network structure. This paper describes new parameters to determine such thermal behaviors as the Initial Softening Temperature, and Maximum Fluidity Temperature of coal, Re-solidification Temperature, Initial coking Temperature, etc ., accompanying with the Arrhenius's activation parameter.

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AIST expressed molecular formula of coal by CH_mO_n, and obtained the number of atomic bond such as C-C, C-H, C-O and O-H in it based on the data related to the chemical structure of coal, and estimated its standard enthalpy of formation (h_f). Gross heating values of 100 kinds of standard sample registered in Coal Bank of AIST calculated from h_f estimated by our method. Results of calculation agreed with those measured by calorimeter with accuracy better than around 3%.

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We have succeeded to estimate h_f of coal from the number and the energy of bonds among C, H, and O atoms in coal molecule. It made possible to discuss the chemical structure of coal based on the number of aromatic carbon bonds and that of aliphatic one or C_l-C_l. The number of C_l-C_l bond in coal is evaluated in the range of about 2 to 3 for lignite, 2 to 8 for sub-bituminous coal, 2 to 6 for bituminous coal, 2 to 4 for high rank bituminous coal and 0.3 to 2 for anthracite.

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Rayleigh scattering behavior of asphaltene dispersed in toluene and a mixed solvent of 10% pentane in toluene (10-100 mg/L) was monitored using a multi channel photo detector (λ = 500-1000 nm). Based on Rayleigh law a relationship between observable radius and molecular weight of asphaltene, r^6/Mw, was obtained. The maximum was observed at about 50 mg/L, coinciding with previously reported nano-aggregate concentration of asphaltene.

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Dimethyl Ether (DME) is a clean and economical alternative fuel which can be produced from various resources as natural gas, coal, biomass through synthesis gas. The properties of DME is similar to the properties of LPG and it can be used for various fields; power generation fuel, home fuel, etc. DME is already produced and utilized as LPG alternate for domestic and industrial use only in China. It has not been clearly understood that in China, DME has been used as a mixture of unused coal bed gas. In this study, to operate micro dynamo supplying a mixture fuel of butane and DME, the fuel consumption and exhaust gases (NO,CO) was measured From the experimental result, which an increased in the mixing ratio of DME, the percentage of CO was reduced, but the percentage of NO increased. Soot generation was not observed either.

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Mongolia serves approximately 73% of primary energy with coal. It will be a big key of the economic development in future to increase coal production and utilize coal. Approximately 80% of coal generate electricity and approximately 9% are for house heating and use coal for a heat source of the cooking. The construction of a new power station, an increase in production of the semi-coke for houses as serious pollution-abatement measures occurring now and an industrial use of new coal utilization development such as coal gasification, steel cokes etc. are planned. As for domestic use, the coal is lignite with 30-40% of total moisture and the export coal which increases rapidly in late years is coking coal of high quality. JCOAL carried out a rationalization plan of coal mine, demonstration of effect of the semi-coke, the investigation into about the CCT introduction guidance, analysis by the trust from the governmental organization until now. The paper presents the latest coal circumstances and issues in Mongolia and considering the future prospects.

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DME synthesis catalysts were prepared by a conventional precipitation method. Nitrates of Cu, Zn and Al (molar ratio was 6:6:1) were precipitated by 0.5M and 1M of Na_2CO_3 solution using with an automatic micro pump and a chemical glass pipette, respectively. The first catalyst (CZAγAl_2O_3 (L)) prepared from the diluted precipitation agent gave a larger surface area, pore volume and smaller particle size of active Cu species compared to those of the last catalyst (CZA-γAl_2O_3 (P)). Two catalysts were evaluated under the same reaction conditions (H2:CO-1:1, GHSV-1000 ml/g・h, T-2600C, P-4 MPa) with a slurry bed reactor. The CZA-γAl_2O_3 (L) provided the highest catalytic activity of 76% CO conversion and 55% DME selectivity (in C-mol%) after 9h reaction. It is supposed that the diluted concentration of Na_2CO_3 precipitation agent caused a formation of the fine and uniform distribution of active metal species of DME direct synthesis catalyst.

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