We clarified that 43% of water contained in Loy Yang brown coal (water content was 53wt%) was bonded with coal surface by thermoporometry. Capillary water and free water were completely desorbed under less than 80% of relative humidity. The pore radius of the coal was distributed from nm order to submicron order, and the peak of the pore radius was 3nm.

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Chemical structure analysis of mobile component in coals using solid state NMR is very difficult because of mixture components (mobile and immobile). Recent modified CRAMPS is able to find chemical information of mobile component, as immobile component is removed using the difference of T_2 value. Modified CRAMPS is very powerful and useful in order to clarify the chemical structure of mobile component in coals because this component has strong relationship with the melting and softening property of coals.

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Coal carbonization process is strongly affected by the presence of metaplast components. In order to achieve an effective generation of metaplast, transferable hydrogen in coal, which was measured by the reaction of coal with anthracene at 420℃ for 5min, could be a key factor. Consumption of the transferable hydrogen with the heat treatment in an open system was largely different from that in a batch system. In a real coke oven, heating system is semi-batch type so that the authors would discuss plastic behavior of coal in a batch system by referring to the pyrolytic behavior including action transferable hydrogen.

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EPR characterization of paramagnetic species in coking and slightly coking coal has been carried out using high temperature in-situ measurements and microwave power saturation technique. The EPR spectra of coal samples obtained with high temperature in-situ measurements consist of at least three components, and change in the intensities of the components during heating depended on the properties of coals. The microwave power saturation results indicated that the origin of paramagnetic species in coal are different by the properties of coals.

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Molecular weight distribution of heavy oil fraction was investigated using LD/MS. Molecular weight by LD/MS (MWms) was larger than that measured by GPC using polystylene (MWps) as calibration standards at MWps less than 800, the both was almost the same at MW of 800-1600, but MWms was almost constant (about 1800) at MWps higher than 2000, showing the same tendency as H/C variation. These results suggests that the average MW of single molecule of asphaltene is limited at about 1800, and the higher MW was resulted by the aggregation of such molecules.

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The Marlim VR was separated into asphaltene and maltene fractions using n-heptane-toluene mixtures (heptol). The separated fractions were characterized by elemental, NMR and GPC analyses. The elemental analyses of asphaltenes were not significantly different, except the oxygen content of the AS20% (3.90), which is slightly higher than others (2.06〜2.92). The AS30% was highest in H/C ratio (1.18). Molecular weight averages (Mn) of the asphaltenes are in the range of 600 to 850 daltons. Coking tests of the maltene fractions recovered from heptol containing 0-30% toluene are classified into BAD and GOOD asphaltenes. The former has higher aromaticity and quaternary carbons and produces more coke than the latter.

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Diffusion coefficients of some petroleum asphaltenes and resins in chloroform solution were measured by using pulsed-gradient spin-echo ^1H NMR. Effects of asphaltene type and concentration were studied. From the experimental results of diffusion coefficients, mobilities and the aggregates sizes of samples were estimated.

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In the previous study, the evolution of H_2O, CO and CO_2 during temperature-programmed oxidation (TPO) of three Chinese anthracites was analyzed. The sources of evolved H_2O are not only organic moiety, but also from adsorbed water and mineral matter. By eliminating the latter contribution, we determined the amounts of H and C evolved only from organic moiety of anthracite. These data then gave us useful information on the structure of anthracite. In this study, an average structure image was drawn based on the TPO data, and an average layer size was calculated. Furthermore, the average layer size of anthracite was evaluated from TEM image analysis. In addition, the crystallite size, L_a, of stacked graphene layer of anthracite was evaluated by a conventional XRD analysis method. The order of these size corresponded well to each other.

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Hydrous treatment of brown coal was investigated to evaluate the effects of treatment time and structural changes. The experiments are carried out in the presence of water in a batch reactor under nitrogen atmosphere at 350℃ for 2-72h. Structural changes occur during the treatment even more than 2h. Brown coal treated for 72h contained less oxygen, more aromatic carbon than that treated for 2h.

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Many studies on water treatment of coal have been carried out s, but its effectiveness for the upgrading of coal property and reactivity is still controversial, and the mechanism of water treatment is not well understood. The results on the effects of water treatment of coal on solvent extraction and liquefaction, including our recent result, will be reviewed.

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Caking property of coals strongly affects the resultant coke strength. Therefore, the evaluation method of caking property is crucial for coke-making technology. Generally, the Gieseler plastometry and dilatation tests are used to measure the caking properties of coals. But these tests have disadvantages when they're applied to poorly-coking coals. The caking properties of coals were measured by means of newly established NMR method. And it was found that caking properties of poorly-coking coals could be evaluated by the NMR method. Furthermore, caking properties of coal blends consisting of coking and poorly-coking coals could be measured by the NMR method. And new method to evaluate caking properties by NMR has been discussed.

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Microfocus X ray computerized tomography is a high resolution and non-destructive technique for examining internal structures of coke. The change of internal structures of coke (30mmφx30mmH) during CO_2 reaction was evaluated by using microfocus X ray CT. The coke samples were scanned at 80kV and 70μA. A high-resolution sensor and enhanced accuracy of image reconstruction software lead to a spatial resolution and a high contrast, which resulted in images of 1024x1024 pixels, each pixels about 33x33μm. Comparing X ray CT images of non-reacted coke with those of reacted coke, coke structure was porous, because pore size was large, micro crack extended due to the connection with pores and the reaction ratio of inert coke was high. Microfocus X ray CT could be a useful tool for evaluating the structure of coke and the change of internal structures of coke during CO_2 reaction.

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Upgrading of low rank coal for the production of solid fuel and cokes material is considered to be the most promising topics from the environmental point of view. In this study, liquid-phase upgrading of low rank coals (Taiheiyo, Buckskin, Kansk-Achinsk, Yallourn and Fortuna coals) was investigated at 350〜440℃ using decalin and coal tar as solvent under 2MPa of initial nitrogen atmosphere. Coking property of upgraded coal obtained from thermal and catalytic reaction of subbituminous and brown coal with solvent was evaluated in fluidity measured by gieseler-plastometer and discussed with analytical data.

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Raman spectroscopy is well known to be a powerful tool to characterize graphitic carbons. However, the interpretation method of the spectrum for amorphous carbon has not been established. Further more, some carbonized materials are rather heterogeneous, which means the Raman spectrum varies from point to point. In this study, Raman mapping was performed in the area of 100μm square by use of micro laser Raman spectrometer with mapping stage to characterize various carbonaceous materials.

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Attempts were made to estimate a reaction rate of coal chars prepared under various pyrolysis conditions using a random pore model (RPM). In order to calculate the pore characteristic parameter ψ in the RPM, Pore structure of char was assessed in terms of mercury porosimetry. The ψ value tended to decrease with higher pyrolysis temperatures and the reaction rate estimated with the ψ value was consistent with the measured rate only in the initial stage of reaction. It was also suggested that there was a different ψ value in/after the middle stage of reaction from that in the initial.

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Compared with the hydroliquefaction of Adaro demineralized coal added the oil soluble complex of Co, upgrading of coal enhanced although the amount of transferred hydrogen was almost equal on the reaction of the Co exchanged coal. It was considered that the catalytic activity of the exchanged Co appeared significantly due to the fine dispersion of Co into the coal matrix through the exchange with proton of carboxyl group in coal.

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Coke-oven gas (COG) contains about 30wt% of tar. This study aims to convert the tar into light gases. When the tar was pyrolyzed in helium, the coke yield reached more than 70%. Reactions of tar with gaseous components consisting COG played an important role for improving the gas yield. When the tar was decomposed in the presence of CO_2, the CO and H_2 yields increased and the molecular weight of product tar decreased from those in the absence of CO_2. The CH_4 yield increased when H_2 was added.

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The Japan Iron & Steel Federation, as a voluntary energy-saving action plan, proposed a 10% energy reduction by 2010 with 1990 as the basis. Furthermore, it has put forward an additional 1.5% energy saving by the use of waste plastics as a metallurgical raw material. The investigation of the use of waste plastics by steel industry has mainly focused on processing in blast furnaces. The coking process is expected to be suitable for the utilization of waste plastics because the process provides high temperature (〜1200℃) and reducing atmosphere. By laboratory tests and actual coke oven tests, the product yields of the typical waste plastics, when pyrolyzed in a coke oven, were approximately 20, 40 and 40 mass% for coke, gas, and light oil & tar, respectively. It was found that the operation of 1 mass% addition of waste plastics into coal charge was feasible. Using the life-cycle assessment (LCA) methodology, the waste plastics recycling process in coke ovens was estimated. The process is thought to be effective to significantly reduce carbon consumption.

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The combustion technologies to achieve a high productivity in SCOPE21 process were investigated by using the actual scale test oven. The combustion conditions to achieve low NO_x and uniform heating were clarified. The design of coke oven in the pilot plant was based on these results. The combustion targets for the low NO_x and uniform heating were confirmed to achieve by the test operation.

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A continuous monitoring technique for the coke oven gas (COG) used as an energy source in the iron and steel making works was developed. Using this system, the differences of the gas generation behavior by a coal combination could be monitored clearly. Moreover, as a result of comparing the COG behavior with the generating gas from a coal measured by the laboratory monitoring system, it was shown that COG was based on the additivity of gases from each combination coal.

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Hot Coke Oven Gas (COG) is not thermally utilized in steel mills because of contamination of tar. Hot COG from the test unit of a coke oven was partially-oxidized at 1,000 to 1,200 degree C below atmospheric pressure, using a small-scale gasification unit and more than 98% of carbon material was continuously gasified. Doing a preliminary feasibility study of the process, the production cost of hydrogen from hot COG was also estimated to be less than that produced by the conventional processes, based on the capacity of 2,000 ton-cokes per day.

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This work was aiming at examining effect of hydrogen bonding on extraction of subbituminous coal at elevated temperature. The extraction yield of 34wt% (daf) was obtained for Wyodak Anderson subbituminous coal with a light cycle oil at 360℃, while for the O-acetylated and O-methylated coals, 48 and 52wt% (daf) were obtained, respectively. In addition, the extraction yield of the acid-treated coal was 42wt% (daf), lower than those of the O-acetylated and O-methylated coals. These results suggest that release of hydrogen bonding in the coal gave a significant effect on the extraction yield.

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Structural characterization of ashless coals obtained from 200℃ to 360℃ in a nonpolar solvent of 1-methyl-naphthalene (1-MN) or a high polar solvent of N-methyl-2-pyrrolidinone (NMP) was carried out. The characterization results for bituminous Upper Freeport ashless coals showed that the aromaticity (f_a), aromatic hydrogen to carbon ratio (H_<ar>/C_<ar>), and degree of substitution (σ) were almost similar, regardless of the extraction conditions. For bituminous Illinois No. 6 and subbituminous Wyodak coals, NMP strongly interacted with coal extract during thermal extraction, resulted in high extraction yields, while, when 1-MN was used as extraction solvent, relatively low molecular-weight components were extracted.

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Direct coal injection to a gas turbine is expected as an advanced high efficiency power generation technology. "Hyper-Coal" is a fuel to the direct coal injection, and must be extremely low ash and low alkaline and alkaline-earth metals concentration. In this paper, in order to incorporate "alkaline and alkaline-earth metals removal process" into "coal solvent extraction process", the ion exchange treatment with H-Y zeolite were investigated under high temperature and pressure condition (360℃, 10atm). Agglomeration test of the zeolite and Removal Test of Dissolving Sodium in Nonpolar Solvent were also examined.

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Hyper-coal is a solvent de-aching coal. Coal is exratcted with 2-ring aromatics, and insoluble is removed from the solution by settling and filtration. Usually, several hundred PPM of ash is remained in Hyper-coal, even though the solution is passed the 0.5μm of filter. This paper focuses about the characteristics of the remaining ash in Hyper-coal. The metallic element component in Hyper-coal is largely different from the raw coal; Fe, Si and Ti occupy the majority in the remained ash. The existence of organic metals such as siloxanes are confirmed, but the quantity is negligible. A TEM image indicates that the Hyper-coal ash is formed by nano-meter particles. When the solvent is removed by distillation, rich domains of Si, Al, Ca and O are appeared on the surface of Hype-coal in the SEM-EDX images. It is considered that the almost remaining ash may be the ultra fine particles, those are too small to be filtered. The aggregated metallic compounds may be formed by the effect of concentration. On the other hand, such a rich domain is not appeared on Hyper-coal particle when a flasher removes the solvent. It suggests that the organics (Hyper-coal) and metallic compounds (ash) are formed separately by flashing.

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The purpose of study is to develop standard methods for analysis of trace elements in coal by ICP-OES and ICP-MS combined with microwave-assisted digestion. It is strongly needed to develop safe and efficient digestion methods compatible with the instrumental analyses. In this study, we try to use a mixture of HNO_3 and H_2O_2 as coal digestion reagents. The use of this simple mixture without addition of conventionally used reagents HF, HCl or HClO_4 is favorable to a stable and simple instrumental operation. It was interesting to find that almost all the trace elements examined were successfully determined with reference to three standard coals.

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This paper presents an analytical solution method to obtain the emittance of coal-ash in the high-temperature atmosphere. The sample was placed in the electric furnace(max. 1150℃) having a tube-dropping mechanism. Once the cold tube, which removes the reflection component, has been dropped into the furnace, radiation intensities from the sample began to decrease. Transient changes in the intensities were compared with the theoretical values. Our method is unique in applying the transient thermal conduction analysis to the determination of the emittance. For the verification of our method, the emittance of metal oxides were measured at 700℃ in the wavelength of 0.9μm and compared to the publish values.

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Coal ash particles formed in high temperature furnace is classified in 'included particels', packed in combustible components of coal or char, and 'excluded paticles', expelled from combustible components. The adhesion characteristics of included particle and excluded particle are completely different even though both are sticky molten particles. CCSEM analysis of mineral matters in gasifeid char and pulverized coal clarified that ratio of included particles of major mineral (Kaolinite and Quartz) have a good correlation with ratio of excluded particles among molten ash particles formed in coal gasifier.

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The predicting method for Methylene-Blue (MB) adsorption amount of coal ash was developed by investigating the influence of coal properties on MB adsorption amount. MB adsorption amount per weight of unburned carbon at the same kind of coal was in proportion to the uncombustion fraction calculated from the unburned carbon concentration in fly ash. The change of MB adsorption amount per weight of unburned carbon to the uncombustion fraction increased according to the decrease of Fuel-Ratio. This correlation made it possible to predict the line which showed the relationship between MB adsorption amount and unburned carbon concentration in fly ash for each kind of coal whose Fuel-Ratio and ash content were known.

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There were few studies on the relation of column flotation results with the characteristic features of coal. We investigated the liberalization of minerals in coal with wet-grinding on by mineral analysis of CCSEM. Then the relation between the liberalization of minerals in coal and the ash rejection was studied, and the effect of the composition and distribution form of coal minerals on flotation results was reported.

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A model study was carried out for the elution behavior of organic matters in the waste water from coal piles. Organic matters were extracted from sample coals with hot water in the hot extraction process. When the extract temperature was increased, the concentration of organic matters increased in aqueous phase. The ecological influence of water-soluble organic matters from coal was investigated. The extracts of Loy yang coal have an endocrine activity. The same examination was investigated for the elution behavior of organic matters in the waste water from hydrothermal treatment process.

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Heteroatom-containing molecules in of South Banko coal liquid distillate were identified by the aid of gas chromatography with atomic emission detector. (GC-AED). Thiophenes and benzothiophenes were found to be the major sulfur compounds. Pyridines and anilines, and phenols were the major of nitrogen and oxygen compounds respectively. Heteroatom conversions on hydrotreatment over a series of NiMo catalyst are different. In hydrodesulfurization of CL, sulfur species were completely desulfurized by 60min at 360℃. However, hydrodenitrogenation and hydrodeoxygenation were more difficult even at severe conditions of 400℃. The higher surface area and acidity of catalysts showed the more heteroatom removal. Anilines are the most refractory species to convert among the nitrogen species. Hydrodeoxygenation of CL showed the difficulty in converting oxygen species at the present conditions and dibenzofuran was the most difficult to convert for oxygen species.

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Four Indonesian low rank coals, South Banko (SB), Berau (BR), Tanito Harum (TH), and Adaro (AD) were acid treated with HCl. Raw and treated coals have been pyrolyzed by thermogravimetry and differential thermal analysis in an nitrogen and oxygen gas, and liquefied in electromagnetic driven autoclave, respectively. Product of pyrolysis and liquefaction were compared to understand effect of acid treatment. Acid treatment increased volatile matter and oil of pyrolysis and liquefaction yields, respectively.

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This paper first aims to evaluate the possibility of producing organic calcium through use of pyroligneous acid and raw limestone. The factors affecting the reaction above was discussed including the particle size of limestone, pyroligneous acid type and other parameters such as reaction temperature and time. Secondly, two low-ranked coals were mixed with the calcium-enriched pyroligneous acid to evaluate the possibility of in situ desulfurzation using the organic calcium produced via the reaction mentioned above. The experimental results suggest the feasibility of reaction between pyroligneous acid and limestone at mild conditions, which is obviously controlled by the pyroligneous acid type, i.e., its acidity. The soluble calcium within pyroligneous acid is mainly in form of calcium acetate, which has a low decomposition temperature of ca. 400℃, far less than that of raw limestone being ca. 700℃. Since of its solubility, calcium within pyroligneous acid was more readily loaded on the coals, forming the particles less than 0.5μm in the impregnated coal matrix. During coal combustion, the loaded calcium first underwent quick decomposition, the formed ultrafine calcium then reacted with the evolved sulfur, which led to formation of much gypsum having size around 1.0μm. As a result, the desulfurization efficiency more than 80% was obtained after the complete combustion of impregnated coals.

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Production of hydrogen-rich clean gas was conducted by steam gasification of woody biomass using calcium as a CO_2 sorbent at different reaction temperatures (200-650℃), in order to examine the gasification mechanism. From the results obtained, initially (<500℃) hydrogen mainly derived from shift reactions of steam with CO obtained by thermal degradation of the biomass structure and that by reforming of water-soluble tar. Then (>500℃) decomposition of heavy tar was promoted, resulting in a large increase in product gas yield. During the experiment, CO_2 evolved was completely absorbed into calcium as CaCO_3. Moreover, water-gas shift reaction successfully proceeded, since almost no CO was detected.

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Steam gasification of woody biomass using Ca-based CO_2 sorbent for production of hydrogen-rich clean gas has been studied. From a view point of optimum cyclic utilization for Ca-based sorbent, reaction behavior was investigated experimentally and theoretically. A kinetics for Ca(OH)_2/CaCO_3 reaction system was proposed and was employed in the theoretical calculation with Ca(OH)_2/CaO and CaO/CaCO_3 reaction systems. From the result, taking account of Ca(OH)_2/CaCO_3 reaction system made the calculation correspond to the experiment more. It is indicated that the calculation will be able to simulate adequately the experimental reaction behavior.

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In order to evaluate bitumen-derived gas oil (OSL) as a diesel fuel, the engine test of the mixture of hydrogenated OSL and middle east diesel fuel was carried out. The amount of PM was not affected by the addition of OSL, and dependant on the aromatic content of the diesel fuel. Bitumen-derived vacuum gas oil(OSV) was mixed with middle east vacuum gas oil, and hydrotreated over NiMo/Al_2O_3. The product distribution of FCC was estimated from the properties of the feedstocks, which indicated only a slight decrease of gasoline yield by the adition of OSV.

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Hydrocracking of middle east heavy oil was carried out by using a slurry-bed reactor, and the performance of several pulverized catalysts were evaluated. Limonite and NiMo/Carbon provided good operations at 460℃ under H2 8MPa without any appearance of coke formation. The hydrodenitrogenation was not accelerated by both catalysts, but the NiMo catalyst improved the removal of sulfur compounds remarkably.

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Combinatorial approach comprised of high-pressure HTS (high-throughput screening) reactor, artificial neural network (NN) and all-encompassing calculation was applied for the development of catalyst for methanol synthesis. Since the optimum catalyst composition is usually affected by both preparation and reaction conditions, composition of catalyst (Cu-Zn-Al-Sc-B-Zr), calcination temperature (300-360℃) and the amount of precipitant (1.0-2.5times the equivalent to total cations) were optimized simultaneously under pressure (1MPa). In the HTS reactor based on a 96 microplate system, activities of 190 catalysts prepared by randomly determined parameters, were measured to obtain training data for NN. After training, the NN can map the catalyst activity as a function of catalyst composition and parameters for catalyst preparation. The 2.6 million activities of all possible combination of the parameters were predicted by the NN to find the global optimum.

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In order to develop an efficient and low cost absorbent for H_2S removal at a high temperature, Yallown coal-supported calcium ferrite was prepared from oyster shell. H_2S breakthrough curve was observed with a fixed-bed reactor equipped with quadrupole mass spectrometer (Q-mass). Surface area of the prepared absorbent showed 37m^2/g and carbon remained showed 10%. Coal-supported calcium ferrite exhibited the high absorption capacity (about 100%) at 500℃ and could efficiently remove 4000ppm of H_2S to less than a few ppm.

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[in Japanese]

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Removal of mercury vapor in simulated coal derived flue and fuel gases over activated carbon and iron oxide adsorbents in a temperature range of 80-150℃ using a flow-type packed-bed reactor was studied. Both activated carbon and iron oxide captured elemental mercury vapor in the simulated flue gas in the absence of H_2S. The Hg removal activity was accelerated by the presence of H_2S. The activated carbon was more active than the iron oxide at 100℃ for the simulated flue gas in the presence of H_2S. The iron oxide was more active than that of the activated carbon for Hg removal from the simulated fuel gas.

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The effects of reaction time and temperature on coprocessing of coal and plastics were investigated. In the initial stage of the coprocessing, both radicals derived from coal and plastics by the thermal decomposition combined, and the increase of toluene insoluble (TI) occurred. However, a part of it was upgraded by the hydrogenolysis with the increase of reaction time, as a result, the increase of oil fraction occurred.

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Hydrogasification of coal has been developed to produce methane (SNG) directly from coal. For the future operation, co-feed of waste plastics with coal is under consideration in order to diversify feedstock. We had already studied the hydrogasification of polyethylene (PE) and coal/PE mixture in the ratio of 50:50. Significant synergistic effect on the methane production was observed when coal was mixed with PE. Considering an industrial application of hydrogasification process, it is important to obtain the knowledge about hydrogasification of a mixture with lower amount of plastics. In this study, coal/PE mixture hydrogasification was carried out, using lower concentration of PE in the samples. Reaction was conducted using a batch type reactor at 1073K and under 7.1MPa of hydrogen atmosphere. Reaction time was varied from 1 to 80 seconds. Product distribution was investigated with varying the ratio of coal/PE content. Methane yield from the mixtures were noticeably greater than the values which was calculated from the results obtained from coal and PE respectively with assuming no mutual influences. It is concluded that a significant synergistic effect was observed even when PE content was low. It is suggested that an efficient hydrogasification processes could be achieved by adding the lower content of plastics mixed with coal.

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A recently developed nickel carbon catalyst was used to gasify a number of biomass samples including several municipal wastes, palm oil mill effluent (POME) and wastewater from the MTE coal dewatering process. A plug flow reactor was utilized for the treatment. Residence time and gasification temperature have been varied as experimental parameters. The catalyst generally proved to be highly effective on solubilised carbon regardless of the type of wastewater. Samples with high solid carbon content were subjected to a heat treatment prior to the actual gasification. This pretreatment successfully increased the yield of solubilised carbon in the sample and gasification conversion rate.

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On the coprocessing of coal and waste tire, the optimum conditions, such as kind of coal, reaction temperature and amount of decalin solvent, were discussed. On the coprocessing of lower rank coal (Wyoming coal) and tire, the synergistic effects, such as the decease of residue yield and the increases of oil yield, were appeared. the effects were observed on the coprocessing above 400℃ with 3.0g of decalin solvent.

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