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Volume 62, Issue 10
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[in Japanese]1983 Volume 62 Issue 10 Pages 791
Published: October 20, 1983
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (210K) -
Hiroshi UCHIDA1983 Volume 62 Issue 10 Pages 792-802
Published: October 20, 1983
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe many hot gas desulfurization processes for removing sulfur impurity such as hydrogen sulfide from fuel gas at temperatures above 400°C were identified and classified according to absorbent type into groups employing solid and melt. Each absorbent reacts with the hydrogen sulfide in fuel gas, thus purifies the gas. The sulfided absorbents are usually regenerated by air, steam or carbon dioxide. The hot gas desulfurization processes employing melt absorbents are complicated by serious corrosion and material handling problems. For this reason, recent developments were focused on those processes employing solid absorbents.
The applicability of hot gas desulfurization processes for combined cycle and fuel cell coupled with coal gasification are considered. Hot gas desulfurization processes provide greater overall thermal efficiencies than low temperature desulfurization.
The problems of the attrition of absorbents, the activity loss of absorbents with regeneration and the uncertainty of engineering technology are associated with hot gas desulfurization processes, and need to be further studied.
None of the identified hot gas desulfurization processes presently appear to be ready for commercialization. But the developments of hot gas desulfurization processes with coal gasification are needed to insure future energy.View full abstractDownload PDF (1278K) -
Hiroshi MIZUTANI1983 Volume 62 Issue 10 Pages 803-820
Published: October 20, 1983
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSEspecially in Japan, early termed development of high efficiency coal gasification combined cycle power generation technology must be carried out not only to effectively use the coal as power generating energy souce but to promote the construction of power generating plants.
Under the present circumstance, a survy of R & D of coal gasification combined cycle technologies both at home and abroad was investigated to find out a suitable technology to power generation system.
The subject awaiting solution are,
(1) higy efficiency
(2) applicability of many sorts of coal
(3) environmental conservation enough to promote the construction of power plant
(4) good load following abilityView full abstractDownload PDF (1679K) -
Yasuo MIKI, Yoshikazu SUGIMOTO1983 Volume 62 Issue 10 Pages 821-827
Published: October 20, 1983
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSSix types modified solvent were prepared by mixing preasphaltene, asphaltene, oil (undistillable and heptane-soluble) and distillate: A;oil+distillate (including phenols), A'; hydrogenated A, B; preasphaltene asphaltene + oil + distillate (without phenols), B'; hydrogenated B, C; preasphaltene asphaltene + oil + distillate (including phenols), C'; hydrogenated C. Hydrogenation of solvent was performed over Ni-Mo-Al2O3 at a temperature of 425°C. 80g of Taiheiyo-Coal and 100g of solvent were put into a 500ml stainless steel autoclave and were heated at 450°C for lhr under hydrogen pressure of 150kg/cm2.
In the case when unhydrogenated solvent was used, the extent of coal conversion in the absence of a catalyst was expressed as A>C>B and the yield of preasphaltene was expressed as C>A>B, which indicates that a lower conversion was obtained in a reaction with solvent including heavy fractions, and that preasphaltene was scarcely cracked when phenols were included in the solvent.
In the case where hydrogenated solvents were used, the extent of coal conversion was expressed as C'>B'>A', which indicates that a higher conversion was obtained with solvent including hydrogenated heavy fractions.
Several obvious differences were shown between coal liquefaction and solvent hydrogenation reactions. Phenols and a paraffin in the original solvent were cracked to some extent in the former reaction, and in the latter reaction phenols were cracked completely but no cracking of the paraffin was observed.View full abstractDownload PDF (954K) -
Compound-Type Separation and Analysis of Recycle OilYazaemon MORITA, Yukitoshi KOGURE, Akira NOMURA, Yoshio NIWA, Fusako I ...1983 Volume 62 Issue 10 Pages 828-835
Published: October 20, 1983
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSIn order to characterize the coal liquids, compound-type separation and analysis of the recycle oils in the liquefaction reaction were investigated and following results were obtained.
1) The quantitative separation into five fractions such as acidic, basic, saturated, aromatic, and polar fractions was preferable to evaluate rapidly and simply the recycle oils (Figs. 1 and 3).
2) The acidic and basic fractions in the recycle oil can be satisfactorily extracted by 1∼2 M/1 aq. solution of sodium hydroxide and hydrochloric acid, respectively. However, the extraction should be necessarily carried out rapidly (Fig. 2).
3) The acidic, saturated, and polar fractions in the recycle oil increased with the number of recycle in the liquefaction reaction. On the contrary, the aromatic fraction decreased (Figs. 4 and 6).
4) The major components in saturated fraction were n-paraffins from C13 to C33. The atomic ratio of total carbon to phenolic oxygen in the acidic fraction was about 10. Consequently, it was assumed that the number of aromatic ring was 1∼2 per one phenolic hydroxyl group.The atomic ratio of total carbon to basic nitrogen in the basic fraction was about 14, and accordingly the number of aromatic ring was 1∼2 per one pyridine ring. The average molecular structures were almost independent of the number of recycle in the liquefaction reaction (Figs 7, 8, 9, and Table 1).View full abstractDownload PDF (993K) -
Tomoyuki INUI, Takashi HAGIWARA, Yoshinobu TAKEGAMI1983 Volume 62 Issue 10 Pages 836-840
Published: October 20, 1983
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSSyngas-conversion to methane and C2∼C4 hydrocarbons on composite catalysts has heen investigated by continuous flow method under 10∼21atm. Ni-La2O3-Ru catalyst (1) exhibited higher activity in methane formation and lower activity in C2∼C4 hydrocarbons under 10 atm than those under 1 atm. Fe-La2O3-Ru catalyst (2) has high activity in C2∼C4 hydrocarbons under medium pressure (10.5atm), however, under high pressure (20.6atm) formation of C5+ hydrocarbons added, On the other hand, Co-La2O3-Ru catalyst (3) exerted best performance among the three catalysts for C1∼C4 hydrocarbon synthesis, for instance, space-time yield (STY) for methane of 75.7mol/1l·h and STY for C2∼C4 hydrocarbons of 6.9mol/1·h at 45.7% CO conversion were obtained at the reaction conditions of H2/CO molar ratio of 2, SV of 11400 h-1, 10 atm, and 356°C. It is shown that the catalyst prepared by impregnation method using the silica support having meso (5nm)-macro (600nm) bimodal pore structure has a better performance compared with catalysts prepared by another methods.View full abstractDownload PDF (652K) -
Hideo HOSODA, Akira DEGUCHI, Masakatsu MIURA, Toshimasa HIRAMA, Hiroki ...1983 Volume 62 Issue 10 Pages 841-846
Published: October 20, 1983
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSFluidized bed Combustion of the char produced by the pyrolysis of municipal waste was carried out as a part of a new system of energy recovery from the waste.
The char particles were continuously fed into a fluidized bed of silica sand particles and were burned under single-stage or two-stage combustion schemes. After the necessary conditions for the stable operation were searched, combustion characteristics were investigated under steady state operation and the analyses of inorganic elements contained in discharged ashes were conducted. The suitable design of commercial plant was discussed on the basis of the obtained date.View full abstractDownload PDF (1149K) -
Yoshinori NAKATA, Shigeru UEDA, Yosuke MAEKAWA, Naohide SAKAI, Masafum ...1983 Volume 62 Issue 10 Pages 847-850
Published: October 20, 1983
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSThe effect of blending of two coals with regard to viscosity under high-pressure and high-temperature liquefaction conditions was investigated.
Yubari coal (bituminous coal) paste which had 40% of coal in anthracene oil showed 9000 c.p.of maximum viscosity. But in blending subbituminous or brown coals such as Taiheiyo, Sohya-koishi and Yallourn coals to Yubari coal, the viscosity of the blended coal paste decreased rapidly with the blending ratio. In the case of over 50% blending ratio of non-coking coal, the viscosity showed values close to non-coking coal or was almost the same.
The coprocessing of coking and non-coking coals in coal liquefaction by blending is one way to decrease the viscosity of coal paste without decreasing the coal concentration in feed coal slurry.View full abstractDownload PDF (377K) -
Ryoichi YOSHIDA, Kaoru ISHIDA, Tadashi YOSHIDA, Takeshi OKUTANI, Yoshi ...1983 Volume 62 Issue 10 Pages 851-855
Published: October 20, 1983
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSFor a better understanding of coal liquefaction reaction in 0.1 t/d continuous flow unit of direct coal liquefaction operated at Government Industrial Development Laboratory, Hokkaido, it became necessary to investigate the effect of coal rank/coal particle size on coal hydrogenation with vehicle oil. In the present study, 3 Hokkaido coals of different ranks were scrutinized and the effect of coal particle size on coal hydrogenation with vehicle oil was studied. As a result, it was shown that in Hokkaido coals with a carbon content of 73.0% to 87.4% the effect of coal particle size on conversion was not recognized when coal particles wer pulverized up to ca. 48 mesh (weight mean diameter: 0.102-0.121mm) in the preparation of coal pastes.View full abstractDownload PDF (569K)
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