Effect of the P_<CO2> and the P_<H2O> on the injection desulfurization rate and the solid composition of sorbents under the PFBG condition was investigated. With increasing pressure, i.e. P_<CO2> the desulfurization rate was dominated by the reaction of CaO with H_2S, then the CaCO_3 dexomposition and then the reaction of CaCO_3 with H_2S.

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Flue-gas recycling combustion of coal was experimentally simulated by burning chars as well as their parent coals at 1120K in a miniature fluidized bed into which O_2/CO_2 or O_2/CO_2/H_2O mixed gases were fed. The fuel-N conversions into NO_x and N_2O both depended on the gas composition at the reactor inlet and the dependency was found to be due to that of the conversions of char nitrogen into the oxides. Characteristics of in-bed reduction of NO added at the inlet revealed that burning char and volatiles equivalently contributed to the reduction.

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A new combined desulfurization/denitration (DeSO_x/DeNO_x) process is developed by using a powder-particle fluidized bed (PPFB). In the process, SO_x is removed by continuously supplied fine DeSO_x sorbent of several to tens micrometers, and NO_x is reduced to N_2 by ammonia under catalysis of DeNO_x catalyst. By using model gases containing SO_2 and NO in a laboratory-scale PPFB reactor, the removal efficiency of this process is tested in this paper with respect to the choices of DeNO_x catalysts and DeSO_x sorbents. The titanium-supported catalysts, both. V_2O_5.WO_3/TiO_2 and WO_3/TiO_2, are found to be adaptive for high NO removal, such as greater than 95%, of this process. The copper oxide sorbent, CuO.V_2O_5.K_2SO_4/Al_2O_3, and the aluminum-supported carbonate, Na_2CO_3/Al_2O_3, are capable of high SO_2 removal (>95%) at the stoichiometric ratio of sorbent to SO_2. However, a poisoning of NO_x reduction (DeNO_x catalyst) by such a copper oxide sorbent makes the simultaneous SO_x and NO_x removals, with the efficiency of greater than 95%, be available only for sorbent Na_2CO_3/Al_2O_3.

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In order to investigate the effect of mineral matter on micro-sturctural changes of coal char during gasification, raw coal and acid-treated coal were pyrolized and the chars were observed by fixed-point observation using TEM. And, micro-sturctural changes of carbonaceous material included in coal char during heat-treatment were also observed with similar technique.

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The Development of Coal Hydrogasification Technology to secure a stable supply of substituted natural gas (SNG) from coal at low cost has been performed from FY 1996 as apart of the Japanese governmental new energy program called the New Sunshine Project. The project consists of three research activities which includes the Elemental Research, Supporting Research and Research on Social adaptability. This paper reports results from researches on hydrogasication reaction and on configuration of gasifier.

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The release of inorganic matters from coal char as volatile matters and aerosols at high temperatures and their deposition on lower temperature surfaces were investigated fundamentally. Taiheiyo, Datong and Blair Athol coal char smaller than 250μm held in a ceramic basket were rapidly inserted into an electronic furnace and burned, gasified or pyrolyzed at 1500℃ to release vapor and aerosols of inorganic matters. A packed bed of glass beads of 2.25-3.25μm was placed in the downstream of the reactor. The temperature of the bed was controlled in the range of 100-500℃ to form deposit on the glass beads. The morphological features and chemical compositions of deposits were evaluated by means of SEM and EDAX. The release and formation of ash deposits depends on gaseous environments. It was found that deposition temperature significantly influenced the morphology and composition of deposits. In combustion, the ash deposits consists of volatile components such as alkali, calcium, sulfur and halogen, though in gasification, the ash deposits contains iron in addition to alkali, calcium and sulfur. It is proposed that inorganic vapors heterogeneously deposited on the glass beads surfaces at 500℃, while homogeneous nucleation and growth predominantly occurrs and resultant aerosols are captured on the beads surfaces at 100℃.

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Inorganic constituents in coal are incorporated as discrete mineral particles, ion-exchangeable elements, or coordination complexes. As the mode of incorporation effects the ash formation behavior during combustion or gasification, the quantitative analysis of these forms will be useful in predicting slagging properties. The individual mineral particles having different chemical compositions were determined by CCSEM. The leaching test was also carried out for the analysis of ion-exchangeable elements.

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Chinese coals are classified for 4 types, which are consist of Carboniferous-Permian coals, Jurassic coals, Cretaceous coals and Tertiary coals, on their depositional geologic ages. Each coal type is plotted each area separately on the van Krevelen diagram and calorific value vs volatile matter content diagram. The Tertiary coal is rich in hydrogen content as same as Japanese coals, but the Jurassic coal is less in volatile matter content than other types. Indonesian coal is a little less in hydrogen content than Japanese coal. But conversion ratios of liquefaction for some Indonesian coals are high because Indonesian coals are rich in resins vesicles generally.

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The kinetics of the hydrodenitrogenation of coal liquefied oil obtained from the 1t/d Process Supporting Unit (PSU) using Tanito Harum coal was investigated. As a result, it was found that the hydrodenitrogenation was a second order reaction and the reaction was proportional to the 1.0th power of hydrogen pressure and the 0.6th power of gas liquid ratio (G/L).

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The quantity of heterocyclic compound is contained considerable in coal liquefied oil on the 1t/d PSU, therefore it is necessary to upgrade the oil for supplying commercial product oil. The heterocyclic compound in the liquefied oil causes forming sludge and coloring. At the 1t/d PSU, the process for decreasing heterocyclic compound in the liquefied oil has been investigated by mean of highly hydrogenation in the hydrotreat unit. However, as highly hydrogenated solvent is supplied to the liquefaction unit, it was predicted that the hydrogenated solvent affects the liquefaction reaction system. In this study, the effect of hydrogenated solvent on the coal liquefaction with batch-autoclave is reported.

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A single reactor operation test of the PSU has been conducted using only one of the three reactors in series to investigate the behavior of coal liquefaction at early stage of the process. At this stage, the oil yield was already more than 50wt% with the residue yield as small as 20wt% on daf coal basis.

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Applicability study on coal liquefaction technology in Indonesia has been carried out. Banko coal, Indonesian brown coal, has some superior characteristics in its quality compared to Victorian brown coal. It leads higher oil yield of liquefied oil and higher energy efficiency with less costs. And it shows a very promising results in the economic evaluation.

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The properties of limonite ore were investigated in relation to the catalytic activity for the direct coal liquefaction. α-FeOOH and α-Fe_2O_3 were observed in some limonite ores by powder x-ray diffraction and Mossbauer spectroscopy analysis. A molecule ratio of H_2O/Fe was calculated from iron content and the weight loss during the heating of limonite ore. It was found that the excellent catalytic activity was indicated with a specific limonite ore which had a high molecule ratio of H_2O/Fe with no content of α-Fe_2O_3.

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Slurry concentration is one of the effective way to improve the efficiency of coal liquefaction process. But it is difficult to make highly concentrated slurry especially in the case of treating a porous coal such as brown coal. The Dual Peaks Solvent System, one of core stages in the BCL Advanced Process^<1)>, has been developed to concentrate the coal slurry in the reactor by removing the lighter solvent after dewatering and thermal treatment of coal. The influence of slurry concentration in the method of Dual Peaks Solvent System was examined by using a gas flow type autoclave with Indonesian BANKO coal. The increasing of distillate yield was strongly appeared by the combined effects of decreasing in CLB and hydrocarbon gases. Hydrogen consumption was also decreased with the increase of coal concentration.

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As a part of the New Sunshine Project, the commercializing development of coal liquefaction technology is being continued by using the 150t/d pilot plant (PP). The fact that the 1,000 hour continuous coal-charging operation was achieved in only one year after completion of PP, and then, all the scheduled operation plans could be accomplished demonstrates that the process, design concept, and equipment of this pilot plant are highly matured and are in a level very close to a commercial liquefaction plant.

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It is important to understand the influence of fluid dynamics in the coal liquefaction reactor on coal liquefaction products. In this study, the relationship between the product yield measured at 150t/d-pp/1t/d-psu and fluid dynamics was discussed. The results suggested that the product yield was depend on the mean residence time of liquid phase at large scale plant.

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The product oil and recycle solvent taken from NEDOL processing of Tanitoharum coal in 150ton/day Coal Liquefaction Pilot Plant were distilled into 12 narrow boiling fractions having mid-boiling point temperatures from about 80℃ to 370℃. Major physical, transport and thermal properties were measured and existing property correlations were modified. These property data base was used for design work of a demonstration plant.

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Carboxylic acids with more than 6 carbons produced from aliphatic constituents in coals by the oxidation with RuO_4 were analyzed by GC-MS. Amounts of mono- and di-carboxylic acids increase by a decrease in coal rank, which tendencies may reflect those of alkyl groups and methylene bridges contained in coals. Maximum amount of alkanes was observed for coals with around 80wt%C. Amounts of alkanes with odd carbon numbers exceeded to those of even ones.

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Construction of a coal molecular structure model is one of the most important tasks in understanding the relationships between coal structure and reactivity. In general, the model can be constructed by connecting partial structures, such as aromatic class fragments, bridges, and substituents that have been given by coal chemists. Recently, the advance of the NMR tecnology makes it possible to quantitatively determine the carbon atoms with distinguishing bond type. As a result, it has been clarified that the partial structure set estimated by the coal chemists has less accuracy. In order to solve this problem, we propose the method that the input partial structure set is decided based on experimental data by using integer programming.

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Phase separated structure of solvent swollen coal was characterized thorough its property, of proton flip-flop spin diffusion. It is shown that the fashion of coal swelling is non-uniform in the segment scale and a microscopic phase separation does take place in a scale from several to 20nm even in good solvents like pyridine.

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NMR imaging method is very useful for inhomogeneous materials. However the highly technique and the difficulty of experimental setup are needed in the case of coals without solvent swelling method. And the influence of various magnetic susceptibilities in coals are set your mind on NMR imaging. Therefore, we have applied Single-Point-Imaging. It was obvious that the image of coal was clear significantly as compared with past works because of the effect of Single-Point-Imaging. It was found that the distribution of mobile component was very heterogeneous like the distribution of macerals. Additionally, NMR imaging method is very powerful and useful for studying of chemical interaction between coals and solvents.

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Upper Freeport coal, one of Argonne Premium Coal Samples, was extracted with a carbon disulfide-N-methyl-2-pyrrolidinone mixed solvent at room temperature. The extract obtained was further fractionated with pyridine to get pyridine-insoluble (PI) fraction. The PI fraction is known to swell in methanol and benzene, although it is a part of the extracts, i.e., a solvent-soluble constituent. A computer simulation method of solvent swelling of the PI fraction is proposed. The swelling behavior was estimated from the volume increase followed by conformational changes of the aggregates of the PI by introducing a swelling solvent, methanol. The swelling ratio estimated from the simulation was consistent with the experimental value observed by a vapor sorption measurement. Physical network structure of coal extract fraction is discussed.

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The method proposed by the authers to estimate the distribution of hydrogen bondings in coal was applied to estimate the enthalpies due to the desorption of water and the dehydration reaction. The validity of the proposed method was clalified, and a procedure was developed to estimate the enthalpies from only FTIR spectra.

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An Australian low rank coal (Loy Yang coal) was upgraded by hydrothermally-treated process at 150-350℃. The change of surface properties in treated coal was examined. The hygroscopicity and content of carboxyl group remarkably decreased. The specific surface area of coal decreased as heat treatment temperature (HTT) was raised. The slurriability of CWM, which prepared from treated coal, was much improved. The coal concentration of CWM, which has a viscosity of 1.0 Pa・s, was 34wt%/CWM; whereas that for the 350℃-treated coal was 59wt%/CWM, and the 350℃-treated coal CWM have good storage stability.

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Several low-rank coals were hydrothermally treated at 200-350℃ in an autoclave. The raw coal and treated coals were analyzed by FTIR with a curve-fitting method. The aromaticity and methyl/methylene ratio somewhat increased due to the treatment, while the content of carboxyl group greatly decreased. Also, thermal properties of the treated coals were examined by use of TG-DTA.

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Many kinds of brown coal are attractive energy resource because of their low ash and low sulfur content. However, brown coal generally contains high moisture and has a high tendency to spontaneous heating after drying. We have been developing the Upgraded Brown Coal (UBC) process with high thermal efficiency, to produce a solid fuel from the brown coal by eliminating its demerits. The UBC process consists of coal-oil slurry dewatering, coal-oil separation and oil recovery sections. This paper discusses the reactivity of UBC for low temperature oxidation, in terms of the reaction rate during oxidation.

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Utilization of waste heat from gas turbine for steam gasification of coal is effective for improving the efficiency of coal gasification power generation system. To materialize this system, we examine two subjects. One is to examine the steam gasification reactivity of coal to create the best gasification way. Another is to build up the simulation of the system to show its advantage.

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Yallourn brown coal (YL) was pyrolyzed in a drop-tube reactor (DTR) and a Curie-point pyrolyzer (CPP) at temperatures ranging from 823 to 1173K in N_2 stream to evaluate contributions of the secondary reactions of volatiles to the overall pyrolysis. On the other hand, HCl-treated and Fe-loaded YLs were pyrolyzed in the DTR to compare the effects of ion-exchangeable species on the char surface on the progress of steam reforming of volatiles. The experimental results of YL pyrolysis at 1173K clearly revealed occurrence of H_2O formation by the primary reactions and consumption by steam reforming of tar and hydrocarbons in the subsequent secondary reactions. Ion-exchangeable cations were found to catalyze not only steam reforming of volatiles but also gasification of char.

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The behavior of so-called rapid carbon was examined in the hydrogasification of Taiheiyo coal at 1173K and 1-7MPa using a rapid heating apparatus. The apparent amount of the rapid carbon was found to increase with the hydrogen pressure, and reached about 40% of raw coal at 7MPa of hydrogen. When coal was heated rapidly in N_2 or in H_2 without gas flow, the conversion was limited to only 50-55%daf. However, these chars react rapidly in a stream of H_2 to attain a high conversion, meaning that the rapid carbon was kept in the char. The amount of the rapid carbon decreased with increasing the heat-treatment time in nitrogen and disappeared finally after an adequately long treatment time.

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Feeding ratio of hydrogen to coal is important parameter to design the plant of hydrogasification process, because it determines directly volume and diameter of equipments in the process anit relates to plant cost, running cost and its thermal efficiency. There were some papers showing that the ratio effect on the conversion of coal to methan and BTX, however there also were some objections against this observation. An apparatus that can gasify a coal in a reactor having a definite volume has been made and the details of this effect was investigated. It seems that this effect was the result of competition between two kind of reactions occured around volatile matter, decomposing into gas and condsnsating into liquid droplet.

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Hydrogasification of coal was conducted using a batch type reactor which has a constant volume and was designed for evaluating the effect of hydrogen/coal ratio on hydrogasification reaction at around 800℃. In this work, surface of resulting char was observed by atomic force microscpope (AFM) at the scale of micrometer. AFM images of coal was shown to be relatively smooth. In the images of hydrogaisification chars, however, an ordered texture and agglomeration of nanosphere were observed. From the roughness parameter, deposited surface is not considered to be from pure carbon, but might come from organic volatile matter produced during the hydrogasification reaction.

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The hydrothermal reactions of lime and quartz were carried out at the temperatures of 523 or 573K under autogeneous pressure in an autoclave. The reaction products were more effective as desulfurization agents than lime itself.

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Mixed oxide is one of the potential candidate for desulfurization sorbents of coal gas at high temperature. We choiced double oxide of various combinations by thermodynamic equilibria and confirmed that zinc-manganese metal oxides was high sulfurization performance in a thermobalance reactor.

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We have proposed a new high temperature desulfurizer which utilizes molten carbonate membrane as a sulfide ion conductor, with which sulfides contained in the syngas are dissolved into the membrane and transferred to the back side carrier gas. Experimental results showed that the reaction of gaseous sulfide with molten carbonate membrane is fast and the sulfide contained in the syngas can be actually removed and condensed into the carrier gas.

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We have conducted tests by burning coal and waste such as waste plastics and car shredder dust, using a furnace with a circulating fluidized bed. It was studied the effect of mixed combustion on the emission behavior of HCl, SOx, NO_x, N_2O, heavy metals and dioxins. It was found that mixed combustion with coal reduces HCl, SOx and dioxins. Elution tests of the fly ash from the bag house also show the benefit of mixed combustion.

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Many other works reported the relationship between NO and SO2 concentration. It was difficult to consider the changeable PFBC emissions separately in our work too. According to condition of oxidation or reduction reaction in the exhaust gas, NO, N2O and SO2 emissions were determined. Therefore inverse relationship between NO and SO2 concentration was observed. On stabilized PFBC operation, NO or N2O conversion were able to be calculated in our previous work (ASH equation). More precise estimation of N2O conversion and calculating method of SO2 emission should be carried out however. The cautious study of short span transient PFBC operation explained the interaction of NO, N2O, SO2 and CO concentration. CO emission meant appearance of reducing agent in the exhaust gas, therefore its concentration informed us of exhaust gas reduced condition. Furthermore CO concentration was calculated by the gas temperature, O2 and CO2 partial pressure. These small concentration gas related to experiential ASH^<SN> equation ((P_<NO>/P_<CO>)^2×(P_<SO2>/P_<N2O)=F(Tc)). This equation must resolve the both problems of precise N2O conversion estimation and SO2 emission calculation.

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Two types of nitrogen-containing artificial coals have been prepared using cellulose and model nitrogen compounds. Nitrogen functionality has been investigated by XPS and pyrolysis GC-NPD, and it does not change during artificial coalification. The major products of gas-phase nitrogen are HCN and NH_3 during pyrolysis of artificial coals with different nitrogen functionality at 800℃. It was found that quinoline-type N gives more formation of NH_3 than carbazole-type N.

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Sorption phenomena of methanol on Taiheiyo coal were investigated by repeated uptake and desorption experiments, using various size of coal particles. By comparing methanol sorption isotherms of the samples, it appears that sorption phenomena of methanol on coal is strongly affected by the particle size. As soon as the particle size increases, sorption rate is slower and difference between sorption isotherms for the 1st and the 2nd run is bigger. Particle size could be correlated with the surface of particle, which behaves as "entrance" for methanol sorbing, and influence diffusion inside particle.

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Mild acid pretreatment was performed to modify the aggregate structure and pyrolysis behavior of coals. The pretreatment effectively removed ion-exchangeable cations from lower ranking coals, and enhanced the swelling by polar solvents such as pyridine, and increased the volatile yield in the flash pyrolysis. The pretreatment loosens the aggregate structure of coal through liberating the ion bridge, to form free oxygen functional groups, explaining those enhancement. Pyrolysis of model oxygen-containing compounds was also studied to clarify the roles of cations in the decomposition of oxygen functional groups at the early stage of pyrolysis. The depolymerization mechanism is discussed based on the above results and structural analyses of the pretreated coals.

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A statistical lattice theory was applied to analyzing characteristics of chemical degradation of Morwell brown coal caused by an aqueous-phase O_2 oxidation that exclusively eliminates aromatic ring clusters. The theory predicted well the relationships among changes in the amounts of clusters, bridges and carboxyls as peripherals. A model assuming the coal as a mixture of a fully-developed Bethe pseudo-lattice and m-mers (m=1-40) quantitatively explained the increase in the fraction of DMF solubles with an extent of elimination of clusters.

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The NMR techniques offers non-destructive solid state examination of chemical and physical properties of coal structures. Of the NMR techniques being used for coal studies the most common are based on ^<13>C, using direct polarization due to ^<13>C spin-lattice relaxation approach. But this method has the limitation from the view point of measurement time and information. The present paper discusses the information on chemical functionalities present in three coals and their relative concentrations that provided by multi-nuclear NMR methods.

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The CPD model for coal pyrolysis, which was presented by Grant et al., was modified and improved by introducing several practical approximations: cross linking due to hydrogen bonding and the distribution of bonding density. The model was found to be valid to express the pyrolysis, behavior of a lignite and a bituminous coal.

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To utilize low rank coal more efficiently, it is indispensable to clarify the coal-water interaction. In this work we presented a new method to estimate the distribution of the heat of adsorption, f(Q), for the adsorption of water on coal. A modified adsorption theory on the heterogeneous surface was applied to develop this new method. The distribution, f(Q), could be estimated easily from three sets of adsorption isobars measured by gravimetry. The method does not require any a priori assumptions for functional forms of f(Q) and adsorption equilibrium constant, K_0(Q). The Q value for water-dried coal systeam was found to be significantly different from that for water-raw coal system through the analysis by the proposed method.

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Hydrogen exchange reactions of four Argonne coals (Illinois No.6, Upper Freeport, Pocahontas #3 and Beulah-Zap) and Wandoan coal with tritiated toluene were performed at several temperatures. The hydrogen exchange ratios of coals with toluene were determined from the radioactivity of tritium introduced into coal. Further, in order to predict positions of exchangeable hydrogen in coal, the hydrogen exchange reactions between coal reacted with tritiated toluene and water were performed.

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Physical properties of coal depend more or less on non-covalent bonding or on the resultant associated states of coal. Numerous investigations have so far been done to evaluate the states through observation of characteristics of solvent swelling and extraction of coal. In this experimental work, changes in mobility of hydrogen in coal at equilibrium swelling with mixed solvents of pyridine and CS_2 and its time variation were evaluated by means of ^1H-NMR and compared with those in volumetric swelling ratio. A close correspondence was found between them.

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The pathway of TCNE and TCNQ interaction with coal was investigated based on the spectrum properties of TCNE and TCNQ in NMP. It was found that TCNE and TCNQ do not interact with coal directly. Instead, TCNE and TCNQ form 1,1,2,3,3-pentacy anopenide anion and TCNQ radical anion first, respectively, then the anions interact with coal.

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The Upper Freeport coal's components fractionated by solvent extraction were studied by X-band ESR spectroscopy. The pyridine soluble and acetone soluble NMP solutions showed organic radical peaks. Their powder patterns are anisotropic and broader. The differences come from the magnetic asymmetry about the radical by packing effect.

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Coals have several kinds of interacting sites, such as hydrogen bonds and π-π interaction sites, and form new noncovalent bonds through interactions with various organic materials. In the present study, inverse liquid chromatography (ILC) using a column packed with coal was carried out. The interacting sites, porosity structure in coals are discussed from the retention behaviors of various kinds of organic materials.

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