The removal of dibenzothiophene (DBT) in model hydrocarbon liquid fuel (MF) by Ni-loaded carbon (Ni/C) prepared from lignite has been studied with a flow-type fixed-bed reactor. The performance of Ni/C in the removal of 500 ppmw-S in MF depends on the amount of Ni loaded, and the highest ability is observed at 11 wt%-dry Ni under the conditions of reduction time of 0.5 h and desulfurization temperature of 200 °C. In addition, the time and temperature influence the breakthrough curves, and it is found that the optimum conditions for DBT removal from MF by Ni/C are reduction time of 1.0 h and desulfurization temperature of 200 °C.

This study investigated power output characteristics of the press-type and the conventional DCFC. In the conventional DCFC, the gas products around the anode prevented the carbon particles and ions from reaching the anode, leading to higher overpotential at the anode. To overcome this issue, a novel type of DCFC (press-type DCFC) was developed to swiftly remove gas products on the anode surface by pressing the anode with holes against carbon/carbonate packed bed. As a result, continuous and stable discharge was achieved in the press-type DCFC, and the impedance measurement showed that remakable reduction of overpotential at the anode.

We have recently succeeded in preparing a carbon fiber using an extract produced from a degradative solvent extraction of rice straw, which we call Soluble, as a precursor. We have also found that the carbon fiber produced under certain condition is hollow fiber. In this work, we examined how and when the hollow is formed. It was clarified that the hollow is formed during the spinning process. The hollow formed is retained through the stabilization and carbonization processes. The pretreatment condition of Soluble and spinning speed of melt spinning were found to be main factors affecting the hollow formation.

Hydrogen gas is focused for global warming measure and the stationary energy storage. Hydrogen production from renewable energy is regarded by global warming gas discharge restraint and storage of the surplus electric power as the very effective means in particular. Therefore, the purpose of this research was to product hydrogen gas from Akita Cedar., which is renewable biomass energy and much in Akita prefecture. After Akita Cedar crushed by Tandem Ring Mill was pyrolyzed, the pyrolyzed gas was analyzed in the experiment, and the fundamental property was considered.

Co-combustion of coal and woody biomass is one of the methods for reducing CO2 emissions at coal fired power plants. However, power consumption and differential pressure at mill rise by increase of biomass blending ratio. On the other hand, black pellet which is made by torrefaction or steam explosion have been attracted attention as a method to increase energetic density and improve grindability. In this study, grindability of biomass (white pellet, black pellet) and biomass mixed with coal are investigated by HGI test, semi-continuous HGI test, size distribution, shape. Black pellet has good grindability compared with white pellet. In addition, grindability changed depending on the torrefaction conditions and it was quantitatively grasped in various tests.

Biomass waste is a renewable sources and its effective utilization is indispensable, particularly in Thailand, where massive amounts of biomass wastes are generated. Moreover, charcoal from biomass wastes is regarded as candidates for low priced raw materials for activated carbons. However, the yield of charcoal from biomass wastes is low in general. So, it is essential to develop a method to increase the yield of charcoal during the carbonization of biomass wastes. In this study, Leucaena, which is a woody biomass, was pressurized at around 500 MPa at room temperature, called cold press in this work, to prepare biomass pellet. Leucaena was also pre-carbonized under the mechanical pressure of around 10 MPa at the temperature range of 25 °C to around 250 °C, called hot press in this work, to prepare densified semi-chars. Then, both cold press pellets and hot press semi-chars were subjected to carbonization at around 900 °C. It was found that the char yield of cold press pellets prepared from leucaena was 21.9 wt%, while the char yield of powder leucaena was only 17.0 wt%. On the other hand, the char yield of hot press semi-char prepared from leucaena was surprisingly increased to 27.7 wt%. From the detail analyses of gas formation during the carbonization, it was found that the dehydration reaction was accelerated by hot press carbonization and the mechanical pressure suppresses the evolution of tar components. Therefore, the mechanical pressure is judged to be effective to increase the char yield through the carbonization of biomass.

Zeolite-containing hierarchical composite-supported PtNiMo catalysts were successfully prepared and their reactivity for dehydrocycization-cracking of methyl oleate was investigated. All the catalysts with ZSM-5 showed higher selectivity for aromatics and the highest selectivity and yield of aromatics for PtNiMo/ZSM(90)60A reached about 80% and 13%, respectively.

Carbon supported nickel catalyst has high activity for hydrothermal gasification reaction. Therefore, in this study, a series of catalysts using iron and cobalt as a transition metal instead of nickel were prepared and investigated. 32Fe47C21Z calcined at 700°C showed iron metal, indicating that the interaction between iron and ZrO₂ would be weak which enabled the reduction of iron species. Although 32Fe47C21A 500-N₂ converted more phenol, hydrogen was not produced. In contrast, 32Fe47C21Z 700-N₂ produced the significant amount of hydrogen because iron metal was generated on this catalyst after calcination at 700°C.

Hydrodeoxygenation of phenol using ZSM-5 supported metal catalysts (Fe/HZSM-5, Pd/HZSM-5, Pd-Fe/HZSM-5 and Pd/NaZSM-5) was carried out at 450°C under atmospheric pressure. Fe/HZSM-5 did not promote direct hydrodeoxygenation of phenol to produce benzene. Pd/HZSM-5 showed high conversion of phenol and selectivity for benzene at the present condition. There was no significant difference in benzene yield between Pd-Fe/HZSM-5 and Pd/HZSM-5. Pd/NaZSM-5 showed moderate benzene yield compared with Pd/HZSM-5, which is accounted for the absence of strong acid site on the catalyst. Accordingly, selective direct hydrodeoxygenation of phenol using Pd/HZSM-5 could be explained by hydrogen dissociation ability of Pd combined with the strong acidity of HZSM-5.

Solvent treated rice straws (STRS) were catalytically hydrogenated in 1 MPa hydrogen at 200-350°C for 2 hours. Rh-loaded activated carbon (Rh5AC) or Rh-loaded Y type zeolite (Rh5Y) were used as catalysts. Around 19 wt% of raw STRS was dissolved in cyclohexane. After hydrogenation of STRS at 200°C, the cyclohexane soluble component (HS) increased to 44 wt% independent of the catalyst species. When the temperature increased to 350°C, HS decreased to 36 wt% in the case of no catalyst, while HS hardly changed in the presence of Rh5AC and Rh5Y, which were 42 wt% and 44 wt%, respectively. GC-MS spectrum showed that, an aliphatic compounds were derived by opening one cyclic aromatic hydrocarbon using Rh5Y at 350°C. It is considered that Rh5Y is useful for the hydrogenation of STRS at 350°C.

Some ash particles of solid fuels adhere to heat exchanger tube surfaces, which cause some troubles such as heat transfer inhibition, operational problems and hot corrosion in coal-fired boilers. In this study, the corrosion resistance of the tube materials and the sinterability of ash samples in corrosive conditions were evaluated by Electrochemical Impedance Spectroscopy (EIS) to develop the monitoring techniques. Moreover, corrosion and deposition characteristics of coal ash were evaluated on site using the monitoring probe developed in this study and quantitative analysis of ash samples from deposits and raw coal. As a result, the polarization conductance as the evaluation index of the corrosion resistance varied linearly with Slagging Factor of raw coal, and there were correlations between deposition and ashing sample of raw coal on content ratios of compositions, such as SiO₂, Al₂O₃ and CaO. Furthermore thermodynamic equilibrium calculations were conducted to evaluate the relationship between corrosion characteristics and the liquid phase ratios of coal ash.

Mercury speciation in the coal fired flue gas was studied by the laboratory scale coal combustion test facility equipped with APCDs (Air Pollution Control Devices) such as SCR, ESP, and FGD. Both Hg⁰ and Hg²⁺ were continously monitored at both side of SCR and FGD to evaluate the merucy capture efficiency in APCDs. Behavior of mercury observed in this study were reasonably explained by the catalytic oxidation of Hg0 in SCR, the adsorption of Hg onto the fly ash in ESP, and the absorption in FGD slurry and their combination. With enhancement of Hg⁰ oxidation by SCR, high efficiency of Hg removal in ESP and FGD can be achieved.

Twenty different coal fly ashes generated by a 1000 MWe pulverized coal fired plant were investigated the leaching concentrations for As, B, and Se. Ten kind of fly ashes were over the environmental regulation; therefore the leaching control of trace elements is desired to expand ash utilization. Paper sludge ashes is promised as the leaching material because of high calcium content and a low cost. Eight kind of the paper sludge ashes were gathered from the different paper manifactures, the effect of the leaching control was studied. The No.3 paper suldge was suited to control the leaching of As, B, and Se, because the No.3 PS ash had haigh calcium content and high leaching concentration of Ca. For the fly ash H, 15.5 wt% mixture of the No.3 PS ash was required in the simultanous control for As, B, and Se.

The amount of coal fly ash (FA) increases year by year, so, high volume FA usage is needed to avoid landfill disposal. In this study, to develop the civil engineering materials for harbor/port structures, the solidification material mixed with unburned pulverized shell(FA-Shell Block) was made without using cement. The pH of leaching water from the FA-Shell blocks (150×150×520 mm) was low alkalinity leaching around 8.5, and the compressive strength stayed high after 50 days soak in artificial sea water. Microalgal affinity of FA-shell block as comparisons rock and concrete was carried out under the running seawater for practical use. The adhesion properties of algal cells to surface of FA-Shell block was equal to concrete.

Coal fly ash (CFA), which contains toxic elements such as selenium and boron. These elements are easily leached out to water environment and contaminate surface and ground waters. In this study, the leaching of Se and other trace elements from CFA samples was examined. When CFA samples were subjected to the leaching test which was referred to the notification No. 46 of the Japan environment agency leaching test, the leaching amount of B, Cr, and Se from original-CFA exceeded the standards of soil. The leaching amount of Cr was less than the standard for landfill, although that of Se was not satisfied to the standard for landfill. Also, the leaching of these elements from aged CFA sample was examined and the leaching amount of these elements degreased with the lapse of aging time.

This paper presents characteristics of coal ash emissivities in high temperature atmospheres to discuss heat transfer performances of practical coal-fired boilers. Spectral emissivities of deposit samples were obtained by using a shield tube emissometer and total emissivities were calculated by a simplified equation reflecting their wavelength dependency. Total emissivities were compared for ash deposits sampled from boilers burning Powder River Basin (PRB) coal and sampled from those burning bituminous coal. Coal ash emissivity depends on coal types and changes significantly with ash surface conditions.