Most of simple utilization process of biomass, such as steam power generation, is not economically feasible. To develop an economically feasible multiple utilization process of biomass based on a recently developed pulverization technology, a new stirring engine co-generation process with a direct combustion burner of ligneous powder, a high temperature gasification process and a high temperature hydro thermal treatment process of the water slurry of fine biomass powder have been developed. By the thermal treatment process, about half mass of biomass was liquefied as water soluble saccharides and their related materials and then remained solid biomass was upgraded into high heating value fuel similar to the high quality lignite.

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Heavy metals, such as mercury (Hg) and arsenite (As), which are released as pollutants into air when coals are burned for producing electricity, may induce the development of several diseases, including cancers, in humans. Possible molecular mechanisms underlying the pathogenesis of diseases caused by heavy metals were analyzed. Exposure of cells to HgCl_2 in vitro was found to induce a striking activation of protein tyrosine kinases (PTKs), such as Lck, c-Src and RET. Two steps of mechanisms of PTK activation were demonstrated. First, cell surface receptors were aggregated due to a redox-linked reaction between receptors and metal ions, which caused production of reactive oxygen species (ROS). Second, the generated ROS induced redox-linked dimerization or polymerization and activation of PTK molecules. The target site for redox-linked dimerization and activation of PTKs was thought to be localized in the MXXCW motif of the kinase domain, which is conserved in 80 among 81 PTKs in a database.

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The thermal radiation properties are studied for a cloud of coal char in coal gasification processes. The monochromatic absorption of the sample particles dispersed in liquid paraffin wax is measured spectroscopically at an atmospheric state by using FT-IR The spectra of absorption are expressed in the property of the extinction efficiency in the wavelength of 0.7 to 2.2μm. The char spectra of the extinction efficiency are almost flat over the wavelength. As the carbon content in char decreases, the spectra of extinction efficiency falls gradually. Larger particle size of char shows apparently greater extinction efficiency in the present range of the size.

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Entrained-bed gasifier is used in the IGCC system, which is believed to be an efficient power plant. It is essential to understand gasification behavior of coal. In this study, the structure and gasification reactivity of solid carbons prepared under entrained-bed gasifier conditions were examined. It was found that solid carbons consist of char and coke, which are devolatilized char and carbon deposit from volatile matters, respectively, and their gasification reactivity are different. Gasification reactivity of solid carbons prepared under oxygen-containing atmosphere was higher than that of solid carbons prepared under inert atmosphere.

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Reactions between coal char and mineral matters such as pyrite. quartz. alumina and kaolinite were investigated by heating up to 1600℃ in Ar atmosphere. by using thermo gravimetric analysis combined with off-gas analysis. Addition of pyrite and iron oxide affected the reactions of char/quartz and char/kaolinite and the carbothermal reaction initiated at about 1150℃ that was lower than those for quartz/char mixture by about 150℃ and for kaolinite/char mixture by about 100℃. respectively. Carbothermal reaction was occurred. not only the case of slow heating but in rapid heating.

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In the HyPr-RING method for hydrogen production from coal by using a single reactor, CO_2 absorption by CaO combined coal gasification in gasifier. Accordingly, addition of CaO in coal mixture may influence gasification reactivity of coal, since CaO was reported as catalysis for coal gasification. In this study, coal or char, and coal or char/CaO mixture were gasified with high pressure steam by using a flow-type reactor. It was found that, with CaO addition the hydrogen produced from coal or char gasification was higher about 10-20% than that from coal or char only gasification. Lignite and sub-bituminous coals had higher conversion to hydrogen than that of the high rank coals.

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We examined the influence of carbonaceous structural change and ash behavior affecting reactivity. We developed a novel analysis method using LRS (Laser Raman Spectroscopy) and EDX (Energy Dispersive X-ray diffraction) for this examination. From these observations, Si and Al existence accorded with the rate of non-graphitic carbon at higher conversion of carbonaceous material. On the other hand, our previous results have shown that the ratio of graphitic carbon increases regardless of ash as gasification reactions proceed. Based on these results we inferred that Si and Al existence suppressed char conversion, so the reaction gas was unable to contact with the carbon. The effect of Fe for catalyst was also investigated and it showed catalytic activity for gasification in some cases.

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In this study, coal-biomass briquettes (BB) made by mixing waste coal and larch bark with Ca(OH)_2 as a sulfur fixation agent were pyrolyzed until 1173K in the inert atmosphere, and the obtained char samples were gasified under a stable steam generation at 1173K. As the result, an increased tendency of BB gasification was found with increment of the additive biomass. At the same time, total calorific values of produced gases are highly increased with the comparison of those produced from gasification of its original waste coal.

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The fate of the chlorine present in coal and char during pyrolysis and gasification has been studied with a fixed bed quartz reactor. In the temperature-programmed pyrolysis of a bituminous coal, the rate profile of HCl formation shows the small, main and shoulder peaks at 380, 490 and 580℃, respectively, and the peak at 380℃ almost disappears after water washing. The Cl 2p XPS measurements suggest that part of the HCI evolved at≦420℃ during pyrolysis arises from water-soluble Cl functional groups in coal, and that it may react with the carbon in the nascent char to form organic chlorides. In the CO_2 gasification of two chars at 1000℃, no measurable amounts of HCI and Cl_2 are detectable, irrespective of the extent of char conversion, but water-soluble Cl-species can be detected significantly.

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Advanced process simulator for pulverized coal fired power station has been developed to predict coal quality impacts and their economical performance. In this study, process design of a 350MW power plant is built as an example on ASPEN PLUS. Effects of coal quality on performance of a mill, combustibility, NO_x emission, power consumption of fans were incorporated as linear equations involving coal properties only. Calculation results of power generation efficiency for three different coals show good agreement with actual plant data.

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In Blue Tower process, two staged biomass gasification system, alumina balls used in moving bed. In this study, heat treatment tests of alumina balls with wood biomass were carried out in laboratory scale reactor. Alkali metals, Na and K, added to alumina balls were analyzed with Atomic Absorption Flame Emission Spectrophotometer and SEM-EDAX. It was cleared that a small amount of Na and K were added onto alumina balls.

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The phenomenon of coal ash deposition is observed on the wall in the coal gasifier. The ash deposit interferes with heat transfer and if it is heavy, it causes unplanned shutdowns of the power plant. Therefore, ash deposition behavior on the wall in the coal gasifier should be predicted when the coal type or operational condition of gasifier might be changed. Authors have conducted on the measurement of ash liquid phase ratio to study the continuous ash melting process. The ash liquid phase ratios were calculated from the result of differential thermal analysis and they were compared with the result from thermodynamics equilibrium. And the relationship between ash melting characteristics and sintering characteristics or viscous characteristics, which were evaluated from a viscosity meter, were examined. The discrimination models for sintering and fluidizing of the ash deposit were developed. The models were introduced into the heat conduction calculation program, which calculates the deposit layer surface temperature serially in the growth process of ash deposit layer. And evaluating the thickness of powder layer, sintering layer became possible by considering the sintering temperature and the fluidizing temperature defined from the ash liquid phase ratio.

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A simple model was proposed for char capture by molten slag surface under high-temperature gasification conditions. In this model, char particles were pneumatically carried to the molten slag surface. It was assumed that the char particles were captured if they reach the molten slag surface whereas they were repelled if they reach the part that is covered by the unreacted char particles. Thus the probability of char capture was given by the balance of char feed rate per unit surface area of the slag and the rate of char consumption by the gasification reaction. Experiments were carried out to evaluate the probability of char capture by molten slag surface at 1400℃. A ceramic tube whose bottom was closed was vertically placed in an electric furnace. Slag (mixture of coal ash and limestone) was placed at the bottom of the reactor. Char particles were conveyed by CO_2-N_2 mixture stream to the molten slag surface. CO was produced by gasification reaction at the molten slag at the bottom. The effect of char properties such as particle size, density, and gasification rate, on the conversion of carbon to CO was evaluated. The theoretical results agreed well with the experimental results.

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Recently, high-temperature and high-pressure coal gasification combined cycle systems have been under developed to realize more efficient and ecological coal utilization technologies. In the gasification process, however, slugging and fouling troubles sometimes occur in the section of furnace wall and heat exchanger, respectively, since the operating temperature exceeds the ash melting temperature. Therefore, it is necessary to predict ash behaviors in the gasification process, based on the properties of mineral particles in the raw coals. Objective of this study is to elucidate the formation behaviors of ash particles and deposition characteristic during coal gasification. The experiments were conducted, using a horizontal high-temperature pulverized coal reactor. Ash particles in the reacting particles sampled during reaction were analyzed, using a Computer Controlled Scanning Electron Microscope (CCSEM).

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Previously we have reported that the presence of H_2S was indispensable for Hg^0 removal and the oxygen may play a very important role in the Hg^0 removal. Therefore, it was thought that iron oxide (Fe_2O_3) may react with H_2S to form FeS_x according to H_2S+Fe_2O_3→1/xFS_x+Fe_<2-1/x>O_2+H_2O (1), and some surface elemental sulfur (-S) species which may react with elemental mercury (Hg^0) to form HgS. Although the main purpose of this study is to develop a process for the removal of elemental Hg^0 using H_2S, it is also necessary to understand the reactions between the iron oxide sorbent with the other components of the fuel gas such as H_2S, CO, H_2, H_2O etc. We proposed that mercury removal unit should be located just before the wet desulfurization unit and catalytic COS converter of a coal gasification system. Generally, COS produced during gasification of coal is converted to H_2S catalytically before entering the wet gas desulfurization unit, which is not effective for the absorption of COS. Therefore, if COS is produced during the removal of Hg^0 with H_2S in the presence of CO, this process cannot be put into practical use unless a COS converter is installed after the Hg^0 removal unit. In this study, the relation between sulfidation behavior, the mercury vapor capture performance of iron oxide, and catalytic formation of COS over sulfided iron oxide in the Hg^0 removal conditions was investigated.

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In order to convert synthetic crude oils (SCO) to clean motor fuels, the separation of nitrogen compounds prior to hydrotreatment (HT) was investigated. The nitrogen contents of compounds were successfully removed from light gas oil fractions (LGO) of shale oil, coal liquid and pyrolysis product of bitumen by solid extraction using CuCl_2・H_2O. The following HT greatly reduced the nitrogen and sulfur contents of products to acceptable levels for clean diesel fuel.

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Carbon supported nickel-molybdenum catalysts were prepared using two types of active carbons and carbon black. The catalyst prepared from high surface area active carbon (3070m^2g^1) had the highest activity for both hydrogenation and hydrodesulfurization. Hydrocracking experiments were carried out using a slurry-bed continuous-flow reactor. The bottom content of Middle East atmospheric residue was decreased from 58wt% to <3wt% by the hydrocracking at 460℃.

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Catalytic decomposition of NH_3 in fuel gas components with a low-valued iron ore (limonite) has been studied with a cylindrical quartz reactor mainly under the conditions of 0.1MPa, 750℃ and 45000 1/h. Metallic Fe formed from α-FeOOH present inherently in the limonite promotes the decomposition of 2000 ppm NH_3 in the coexistence of a high concentration of syngas (50%CO/25%H_2) with 3%H_2O added, and conversion of NH_3 to N_2 reaches 96% at 850℃. 10%Mg added to the limonite can suppress carbon deposition from the CO, and the Mg-added catalyst achieves the almost complete decomposition of NH_3 in 50%CO/25%H_2/5%CO_2/3%H_2O to N_2 at 750℃.

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In order to examine the clean utilization of the coal, we did the LCA comparison between the casein which the coal is converted to synthetic fuels (Methanol, DME, FT gas oil) and the case in which the coal is used as it is. As the result, it was found that it can make various environmental impacts decrease considerably by converting the coal to the synthetic fuels. Especially, DME has the effectiveness not only for the aspect of the clean utilization but also the enlargement. utilization of the coal.

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The Dimethyl Ether (DME) is a clean and economical alternative fuel which can be produced from various resources as natural gas, coal or 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, transportation, home fuel, etc. Today 10,000 ton/year DME which produced from methanol is actually used as propellant of spray can. The demand of DME in Japan is 4 million ton in 2010. The demand will increase to 17 million ton in 2020. 50,000 ton/year DME is already produced and utilized as LPG alternate for domestic and industrial use only in China, which will be expanded to 1 million ton in 2010.

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The purpose of this study is the determination of rare earth elements(REEs) in coal by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) after digestion by microwave irradiation. Determination of REEs by ICP-MS shows several spectroscopic overlaps from M+, MO+ and MOH+ ions. Especially, the spectroscopic interfaces are observed from the atomic and molecular species of lighter rare earth elements and Ba during the determination of Eu Gd and Tb In this study, mathematical correction methods that based the at.% abundances of different interfering isotopes and the extent of formation of molecular species determined experimentally have been used to account for various spectroscopic interferences. These methods were well applied to the determination of trace amounts of REEs in various coals.

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The partitioning behavior of boron in pulverized coal combustion is investigated to estimate boron concentration in waste water from power station. The specific gravity separation test for 4 coals and leaching test for 10 coals were performed to investigate boron distribution and chemical form in coal. Boron concentration in coal had an affinity to vitrinite in coal, because boron concentration had positive correlation with vitrinite content. On the other hand, boron concentration had negative correlation with inerinite and mineral content in coal. Boron concentration of specific gravity fraction including high reginite content showed extremely low value. Boron concentration in coal decreases with increase of reginite content Boron exists in coal as water-soluble and water-insolible chemical compounds.

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When several lignites were subjected to hot water extraction (HWE) and hydrothermal treatment (HTT), the leaching of organic matters from coal was evaluated by total organic carbon (TOC). The degree of TOC in the HTT eluent was greatly increased as the HTT temperature was raised from 200 to 350℃. The extracts obtained from the HWE and HTT eluents for LY lignite were assessed in terms of Ames Salmonella mutagenicity assay and acute toxicity test for D. magna and O. latipes. The extract from the HWE eluent (EX-HWE) did not show any notable mutagenicity. However, an appreciable degree of mutagenicity after chlorination was observed for the EX-HWE. The eluent from HTT indicated a considerable acute toxicity for D. magna and O. latipes.

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Biodesulfurisation (BDS) of coal by use of Thiobacillus ferrooxidans was investigated. The % removal of inorganic S was 37-88% when the BDS was carried out for 30 days. The BDS efficiency was varied with the kind of coals, while the efficiency tended to decrease as the pH in the medium increased. The degree of pH was ruled by the amount of Ca leached from coal. When the pH in the medium was artificially controlled to be below 3.0, the BDS efficiency was greatly improved. The BDS process also resulted in effective removal of hazardous heavy metals, such as As, Hg, and Se.

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The objectives are to elucidate homogeneous mechanisms of mercury oxidization and study the important factors on mercury oxidization in the homogeneous reaction system. The mercury oxidation experiments were conducted by injecting Hg gas with HCl or Cl_2 gas, using an electrically heated horizontal tube. Chemical equilibrium and chemical kinetics analyses were also carried out to study the main mercury elementary reaction scheme theoretically. The results show that HCI has little possibility of mercury oxidization. For Cl_2 addition, however, the mercury oxidization is enhanced more. The coexistence atmosphere of H_2O with Cl_2 affects promotion of mercury oxidization.

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In fluidized bed combustors (FBCs), in-situ SO_2 capture is conducted by feeding limestone (CaCO_3) to the reactor to form harmless CaSO_4. Pure CaSO_4 is known to be very stable under oxidizing conditions at FBC bed temperatures (800-900℃). However, the temperature of burning fuel particles or the temperature near fuel feed points where volatile matter combustion occurs are considered to be higher than the average bed temperature. In addition, there exist coal ash particles around the sulfated limestone particles (or fine sulfated limestone powders around coal particles), and the temperature of CaSO_4 decomposition may be affected by the coexistence. The objective of this work is to evaluate the decomposition rate of CaSO_4 mixed with coal ash. The mixture was heated up to 1350℃ in oxidizing atmosphere, measuring SO_2 release and weight change of the mixture. Pure CaSO_4 was found to be very stable and decomposition occurred only at higher temperatures than 1250℃. When coal ash was mixed with CaSO_4, the decomposition and SO_2 release occurred at relatively lower temperatures, for example, 1000℃. Mechanism of the decrease in CaSO_4 decomposition temperature is discussed based on equilibrium calculation using FactSage.

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Boron spectra for two fly ashes were measured by XPS to understand partitioning of boron in pulverized coal combustion processes. Boron functionalities were found as 185eV and 188eV peaks which are soluble and insoluble compounds, respectively. XPS measurements of fly ashes before and after leaching test, and observation of boron devolatilization by solid atomic absorption spectroscopy suggested that 185eV mean H_3BO_3 and another peak is AlB_2.

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To characterize leaching behavior of boron in various kind of fly ashes, leaching rate and partitioning rate of boron were investigated for 4 fly ashes that collected by electric static precipitator in a coal fired power plant. Leaching rate of boron is different by fly ash types, which show from 0% to 85%. Relation between partitioning rate of boron to fly ash and its leaching rate is examined to obtain control factor of the leaching rate for various fly ashes.

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A prediction, prompt detection and suitable control of ash deposition on heat transfer surface are one of the most important factors for a stable and highly efficient operation of pulverized coal fired boiler. Several indices based on the coal analysis have been developed for estimating the slagging potential. However, these indices often give misleading results and are somewhat unreliable, because the slagging phenomenon is affected by not only ash behavior in high temperature but also operating conditions, including boiler load, flame length, flue gas temperature and boiler structure. The integrated computer software package named "Idemitsu Coal Assessment System (I-CAS)" was developed to evaluate boiler performances and judge adaptability of each coal. In this system, the gas temperature at several parts in boiler and the melting behavior of ash deposit are calculated to predict ash deposition growth and their location for each coal type and operating condition.

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Chemical forms of the fluorine and carbon present in fly ashes formed in pulverized coal combustion have been studied with X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD) techniques. Most of the fluorine in the ash samples is enriched on the surface of unburned carbon and exists as covalent C-F bonds. The fluorine content tends to increase with increasing sum of carboxyl and lactone/acid anhydride groups on unburned carbon. HF evolved in the combustion process may react with active carbon sites to form organic fluorine compounds.

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Two bituminous coals, mined in the same coalfield. and coal density fractions were burnt to investigate the impacts of the inherent calcium-based compounds on their PM_<10> emissions. The results indicate the obvious influence of inherent calcium. Combustion of the coal rich in Ca produced less PM_10 than the one lean in Ca. Specifically, the amount of PM_<1-10> having the size ranging from 1.0 to 10 μm, was much low in the case of coal rich in Ca. Effects of included and excluded calcium-based compounds were also elucidated by coal density segregation. The include al-silicates minerals (1〜10μm in diameter) would interact with the excluded calcium-based compounds and agglomerate into larger particles during the raw coal combustion. Accordingly, the amount of PM_<1-10> is reduced greatly.

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Coal combustion-derived PM_<10> contains four volatile elements including S, P, Na and K. Their amounts account for 60% in the particulates ≦0.2μm and about 10% in those ranging from 0.2 to 1.0μm. Sulfates and phosphates are the major species in PM_1. On average, about 5% of inherent S vaporizes and condenses into PM_1 and PM_<1-10>. Meanwhile about 10% of P is found enriched in Pm_1, only 5% of Na is enriched in PM_1, but more than 20% of it is found in PM_<1-10>, suggestive of the chemical reactions between gaseous Na and inherent Al-si, which promotes the growth of Na into larger particles. The transformation behave of K is much complex, which depends on coal type significantly.

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To develop an efficient cleaning process of carbon resources, lead oxide and ionic liquid were used for selective removal of organic sulfur. Lead oxide powder adsorbs thiol selectively as s form of Pb(SR)_2 and a desulfurization extent of 98 % was obtained at a room temperature. The ionic liquid BMIMMeSO_4 shows selective extraction of thiophene. The desulfurization extent of thiophene increases linearly with the number of extraction cycle. Thiol and thiophene were extracted successfully from a mixed solution with lead oxide and ionic liquid.

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We have proposed a new scheme for brown coal conversion consisting of hydrothermal extraction and hydrothermal gasification process. To examine the possibility of the process, four kinds of low rank coals were extracted by water at 300 and 350℃. The extraction yields of Loy Yang (LY), Wara (WR), Berau Binungau (BB), and Thai Lignite (TL) at 350℃ were 54,48,42, and 44wt%, respectively. The residue obtained showed lower hydrophilicity and higher calorific value than the parent coal, being dewatered partially and upgraded. It was confirmed that the proposed process is promising for effective conversion of various low rank coals.

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Reformation of the low quality coal by hydro-thermal treatment was conducted. Firstly, the coal was pulverized into moderate small powder. The coal slurry was prepared by mixing the pulverized coal and water. The coal slurry was filled in the pressurized reactor and then it was heated up 250C to 300C. The coal was reformed by this treatment and the liquefaction components were also obtained in this treatment process. The reformed coal were analyzed in this experiment.

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The Upgraded Brown Coal (UBC) Process is a new technology to convert low rank coal into transportable solid fuel with higher heat value without trouble of spontaneous combustion. UBC demonstration plant with the capacity of 3 ton/day had constructed in Indonesia and operated to acquire data for F/S. It had been carried out stable continuous operation of the plant using Indonesian low rank coal. The characteristics of spontaneous combustion of UBC product is suppressed compared with bituminous coal. As the results of the operation, it has been confirmed that the UBC process could be applied for Indonesian low lank coal on the operation of UBC demonstration plant.

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The addition of some organic and inorganic compounds such as TCNE and LiCl has been found to be effective for the increase in extraction yields of coals and solubility of coal-derived ultra-heavy component, i.e., pyridine insoluble, CS_2/NMP soluble materials at our laboratory. The addition of basic compounds such as riethylamine were also reported to increase coal extraction yields. While, solubility of petroleum asphaltenes in alkanes increases by the addition of amphiphiles such as p-(n-dodecyl) benzenesulfonic acids. The mechanisms for solubilization are discussed.

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Newly developed methodology to characterize macromolecular network structure of coal based on the dielectric property has been studied, forcusing on the frequency effect appeared in the characteristic thermal behavior of the capacitance.

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Solvent extraction/de-ashing process (HyperCoal production) is being developed in Japan. The extraction yield is strongly dependent upon physical cross-linking structures in raw coals, since the mechanism of solvent extraction is directly attributed to relaxation of aggregated structures through noncovalent interactions, such as π-π interactions and hydrogen bonds. Nature of physical cross-linking structures of various ranks of coals is discussed on the basis of results of solvent extraction/de-ashing.

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Ashless coal (HyperCoal) was produced through solvent extraction of coals at 360℃. This work was aiming at establishment of selection index of low rank coals for production of HyperCoal. Relationship between the amount of oxygen-containing functional groups in raw coals and the extraction yield was investigated. A good correlation between the amount of metal carboxylate groups and the extraction yield with an industrial polar solvent, crude methyl naphthalene oil (CMNO), was found and the correlation coefficient was 0.86. This result suggests that thermal extraction of low-rank coals strongly depends on the ionic cross-links rather than hydrogen bonds.

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Hyper-coal process adopts the solvent de-ashing technology to produce the ash-free coal (Hyper-coal, HPC)^<1)>. Coal is extracted with the coal-derived solvent, which consists with 2-ring aromatics, at 360-400℃. The Hyper-coal slurry, which consists with the coal solution and insoluble solid (Resid-coal, RC), is introduced into the settler. The clarified solution and the concentrated solid (RC) are obtained by the high-temperature gravity settling. This paper concerns to the RC sedimentation behavior and the clarification behavior using the batch-type settler. The influences of the settling time, solid concentration were examined. We understood that the 1-2 hrs of settling time is needed for converging the solid-liquid separation under the conditions of 310-380℃, 10-25wt% slurry. The 0.1t/d bench scale unit (BSU) demonstrated stable continuous operations. Ash concentrations in the HPCs were 1000-2000ppm by settling alone, and 300-600ppm by settling-filtration set.

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The purpose of this study is to investigate the removal behavior of metallic elements including major and trace elements during the organic solvent extraction. An attempt was made to examine the partitioning of metallic elements from a raw coal to its HyperCoal and its by-product coal (residue). Good mass closure was obtained for all major elements and most trace elements by means of the advanced analytical technique. It was found that beside high removal of major elements, most trace elements were removed to a large extent but trace elements in HyperCoal had a higher proportion to major elements than those in raw coal. Cr, Ni, and Cu were observed to be susceptible to the contamination during the HyperCoal production process. Furthermore, the sequential acid leaching method was used to characterize the modes of occurrence of metallic elements in coal, and this information was provided to discuss the removal behavior of metallic elements by the organic solvent extraction.

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In order to produce good-quality cokes from coal blends containing low-quality coals as much as possible, thermoplasticity of various coal blends of coking coals with slightly- or non-coking coals was investigated using dynamic viscoelastic techniques. The overlapping of thermoplastic temperature range as well as the increased thermoplasticity of each coal is important for an enhancement in thermoplasticity of the coal blends. For the coal blends with different thermoplastic temperature ranges, the improvement of thermoplasticity was not observed. HyperCoal (coal extract) was tried as a thermoplasticity accelerator for coal blending. HyperCoal is an ashless coal produced by thermal extraction, and the thermoplastic temperature range was significantly wide, in addition to the high thermoplasticity itself. When the HyperCoals produced from low-quality coals were mixed with coal blends, a significant improvement of thermoplasticity for the coal blends was found.

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Hyper-coal (HPC), which is an ash free coal, can be produced by thermal extractions with organic solvents and separation from the insoluble residue. We have made a study to use HPC as a coke making material, and measured CO_2 reactivity of coke samples containing the HPC. The results were as follows. The addition of HPC into coal charge deteriorated coke reactivity, and improved coke strength after-CO_2 reaction.

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Hyper-coal (HPC), which is an ash free coal, can be produced by solvent extraction of coal. We have studied financial analysis and evaluation of Hyper-coal production process which used bituminous coal or brown coal as raw materials. As a result in which case, high economical efficiency was shown, and the commercialization of this Hyper-coal project is expected.

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We have recently presented a new coal fractionation method that utilizes solvent extraction at different temperatures lower than 350℃. This method can separate coal into several fractions having different molecular mass compounds without decomposing the coal. Since it is very important to examine the melting and plastic behavior of the fractions during heating for their effective utilization, thermomechanical analysis was carried out in this study. All the fractions obtained at fractionation temperatures lower than 350℃ from a caking coal melted during heating, whereas only the fractions obtained at fractionation temperatures lower than 150℃ melted for a slightly-caking coal. The temperature at which a minimum apparent viscosity was reached increased with the increase of fractionation temperature. These results suggest that the slightly-caking coal doesn't melt due to lack of the fraction that melts at higher temperature. However, we could obtain fractions from a slightly-caking coal whose melting and plastic behavior is very close to that of synthesized naphthalene-based pitch, so we may be able to use such fractions obtained from cheaper coal as a source of carbon materials.

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Catalytic behaviour of iron-based catalysts on hydropyrolysis of nascent coal tar was studied using a two-stage fixed-bed reactor in ambient pressure. An Indonesian natural limonite ore was mainly employed as a representative iron catalyst at a temperature from 873K to 1023K and in 50 vol. % hydrogen atmosphere. The limonite catalyst exhibited a great activity on coal volatile methanation that methane concentration in carbonaceous gas product was achieved higher than 60% in volume and tarry material was converted almost completely. Comparing with two other iron-containing catalysts, Fe/Al_2O_3 and bof dust, limonite with a high specific surface area showed a high catalytic activity on tarry material hydropyrolysis. The influence of sulphur poisoning on the limonite catalyst was small. Carbonaceous gas products obtained in a 2000ppm H_2S atmosphere with limonite were still up to twice the total gas yield and twice methane yield (in moles) of those without catalyst at 923K.

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