石炭科学会議発表論文集
Online ISSN : 2423-8309
Print ISSN : 2423-8295
ISSN-L : 2423-8295
第59回石炭科学会議
選択された号の論文の48件中1~48を表示しています
開催案内・プログラム
招待講演・特別講演
研究発表
ガス化・燃焼、熱分解・コークス
熱分解・コークス、 カーボンリサイクル
改質・処理・クリーン化、その他
  • 宮本 宗志, 加藤 貴宏, 大川 浩一, 菅原 勝康
    p. 18-19
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    Oxidative treatment with organic peroxides is effective for oxidizing thiophene, which is the main organic sulfur in high-rank coals. The sulfone generated by oxidation of thiophene can be easily removed by pyrolysis at low temperature. However, it is known that the reactivity of thiophenic sulfur to organic peroxides depends significantly on the type of coal. In this study, the relationship between the reactivity of thiophenic sulfur in subbituminous and bituminous coals and coal properties was investigated, and it was confirmed that the reactivity of thiophenic sulfur decreased as the carbon content of coal increased.

  • 任 傑, 蘆田 隆一, 河瀬 元明, 堺 康爾, 奥山 憲幸
    p. 20-21
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    We have proposed a novel coal pre-treatment method that combines oxidation reactions by molecular oxygen and the following reduction reactions by coexisting gaseous formic acid to upgrade a bituminous coal at 90°C-150°C under atmospheric pressure. It was found that the softening and melting performance of the treated coals was enhanced when oxygen and formic acid existed in gas phase at the same time at 90‒130°C. The amount of low-molecular-weight compounds (LMWC) in the coal significantly increased by the treatment, increased by 29% on raw coal’s LMWC basis by the treatment at 90°C in oxygen/formic acid. Surprisingly, the oxygen content of the coal decreased even in the presence of molecular oxygen when formic acid coexisted.

  • 中村 彩乃, 鈴木 亮, ダウセ ペドロ ドミンゴ, 村上 賢治
    p. 22-23
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    A degradative solvent extraction method for upgrading low-rank coal was performed at 200–350°C for 90 min to obtain Soluble, which is a substance dissolved in the solvent at room temperature and include a high carbon content without ash. Furthermore, deep eutectic solvents (DES) have attracted attention for decreasing the oxygen content in Soluble. DES, which was prepared by mixing choline chloride (ChCl) and FeCl3·6H2O, and Adaro subbituminous coal (AC) were added to 1-methylnaphthalene (1-MN) as a non-polar solvent, and degradative solvent extraction was performed in the range of 200–350°C. The effects of reaction temperature and DES amount on the composition of Soluble were evaluated. As the reaction temperature and amount of DES added increased, carbon content in Soluble increased. It was also found that the thermal decomposition temperature of Soluble and oxygen content in Soluble decreased with increasing DES amounts. This decrease indicates that DES promotes the deoxygenation of AC.

構造・物性、灰・微量元素
ガス化・燃焼
ガス化・燃焼、改質・処理・クリーン化
  • 望月 友貴, Javzandolgor BUD, 坪内 直人, Enkhsaruul BYAMBAJAV
    p. 38-39
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    The objectives of this investigation were to prepare an adsorbent with high CO2 adsorption capacity and to clarify the effect of N-doping on the CO2 adsorption of activated carbon (AC). First, N-doped AC (NH3-AC) was prepared by NH3 treatment of AC prepared from biomass, and its CO2 adsorption amount was evaluated. Next, chemical and pore property analyses of the NH3-AC were performed to clarify the effect of N-species on the CO2 adsorption ability. CO2 adsorption ability of AC improved by NH3 treatment until 400°C. In contrast, the ability of NH3-AC prepared at 500°C or higher decreased with increasing NH3 treatment temperature. When the NH3 treatment temperature was <200 and 700-800°C, N% in NH3-AC increased. N1s XPS analysis showed that N in NH3 was mainly incorporated into the AC as pyridinic-N. Pore analysis showed that micropores of 0.55-0.85nm decreased when the NH3 treatment temperature was >500°C. It was concluded that the decrease in CO2 adsorption ability was due to the reduction in micropores. However, no significant change was observed in the pore properties of NH3-AC prepared at NH3 treatment temperature of 200-400°C, suggesting that the increase in CO2 adsorption ability was due to the formation of basic sites by the pyridinic-N introduced during NH3 treatment.

  • 李 泰霖, 崔 哲溶, 福本 一生, 町田 洋, 則永 行庸
    p. 40-41
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    CO2 recirculation in the oxy-fuel Integrated Coal Gasification Combined Cycle (IGCC) system is essential for continuous use of coal in the future. This study presents a detailed kinetic investigation into coal gasification under O2-N2 and oxy-fuel (O2-H2O, O2-CO2) gasifying agents. The effects on polycyclic aromatic hydrocarbons (PAHs) and soot formation in the reductor of a two-stage entrained flow gasifier were simulated using CHEMKIN. The detailed chemical kinetic model includes 202 species, 1,351 gas-phase reactions, and 101 surface reactions. The numerical results showed that the oxy-fuel blown modes promoted tar reforming to complete elimination at 1,200°C (<1.5mg/Nm3). Because of a different tar conversion behavior, the O2-H2O blown mode provided a more potent tar-yield inhibition. In the case of soot formation, the amount of soot decreased under oxy-fuel blown modes. This behavior resulted from hydrogen abstraction and C2H2 addition (HACA) surface growth, and nucleation rate reductions. Also, the PAHs condensation had a weak effect on the soot formation rate among different gasifying agents. This study promises a better gasification process design for a two-stage entrained flow gasifier in an oxy-IGCC system.

  • 蘆田 隆一, 高橋 巧, 任 傑, 河瀬 元明, 堺 康爾, 奥山 憲幸
    p. 42-43
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    We have proposed a pretreatment method for improving coking property of low-grade coals, in which low-grade coals are treated with a reductant such as formic acid at around 60°C. It was shown that the treatment by either aqueous formic acid or formic acid vapor significantly improved the coals’ thermoplastic performance and enhanced the strength of the resulting coke even though consumption of the reductant formic acid was small enough to hardly change the elemental composition of the coals. We have also succeeded in restoring the coking property of weathered coking coal.

  • 加藤 貴宏, Dorcas L. E. UACIQUETE, 小野寺 凱, 大川 浩一, 菅原 勝康, Nakorn WORASUWANN ...
    p. 44-45
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    To prepare ultra-low sulfur coal, we have challenged chemical desulfurization of subbituminous coals using two peroxides, hydrogen peroxide and peracetic acid. In the presence of hydrogen peroxide, oxidation was promoted only at 60°C, accompanied by significant carbon loss. On the other hand, treatment with peracetic acid promoted the oxidation of thiophene with low carbon loss. By combining pre-oxidation with peracetic acid treatment and pyrolysis at 400°C, 74% of total sulfur and 72% of thiophene could be removed while recovering approximately 90% of total carbon as char.

灰・微量元素1
灰・微量元素2
熱分解・コークス、重質油
  • 辻 典宏, 畑 友輝, 藤部 康弘, 鈴木 哲也, 金橋 康二
    p. 58-59
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    For quantitative analysis of aromatic molecules in coal pyrolysis gas, a VUV-SPI-MS system have been developed to continuously measure the generated gases. Coals with different degrees of carbonization have been heated from room temperature to 800°C, and the generated gases have been measured using this equipment to compare the molecular species generated by the different coals types. It has been found that benzene and toluene are mainly detected in the pyrolysis gas of bituminous coals with relatively low oxygen concentrations, while gases containing OH groups such as phenol and cresol are mainly generated from subbituminous coals with high oxygen concentrations. Solid-state 13C-NMR spectra of coking coals corroborate this result, indicating that the proportion of oxygen bonded to aromatic carbon is greater in younger coals. These two results provide insight into the relationship between coal pyrolysis g as and the structure of the coking coal.

  • 坪内 直人, 汪 雨亭, 望月 友貴, 今野 沙緒梨, 宍戸 貴洋
    p. 60-61
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    Formed samples containing biomass (cedar wood powder) were heated first to 450-600°C at 10-40°C/min under pressure in an inert atmosphere and then to 800°C at 3°C/min under ambient pressure. The principal conclusions were summarized as follows: (1) Rapid heating treatment in the softening and melting temperature range of coal was effective in improving coke strength even in the presence of biomass. (2) Formed samples containing 3-5 % biomass without any pretreatment could produce coke of 4-5 MPa, though the coke strength was lower than that of standard blended coal. (3) It was found that biomass modified in 1-methylnaphthalene could maintain the coke strength at the standard blended coal level (approximately 9 MPa).

  • 坪内 直人, 汪 雨亭, 望月 友貴, 今野 沙緒梨, 宍戸 貴洋
    p. 62-63
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    Formed samples with a weight ratio of caking coal : slightly-caking coal : non-caking coal = 15:45:40 were first heated rapidly to 450-600°C at 10-40°C/min under pressure in a stream of pure He, and the temperature was then increased to 800°C at a slow heating rate of 3°C/min under ambient pressure. When the temperature range of the rapid heating was increased from room temperature-450°C to room temperature-600°C, the adhesiveness between coal particles increased and the strength of the resulting coke increased significantly. In addition, the strength of 800°C coke tended to increase with increasing the rapid heating rate. Furthermore, the strength tended to be higher at larger pressure, and the optimum pressure was 1 MPa under the present conditions.

  • 麓 恵里, 佐藤 信也, 柿沼 敏弘, 森本 正人, 森田 剛, 田中 隆三, 鈴木 昭雄
    p. 64-65
    発行日: 2022/10/13
    公開日: 2022/11/01
    会議録・要旨集 フリー

    Fouling deposits in crude oil heat exchanger contain organic compounds and iron compounds. The effect of iron compounds on the formation of the deposits was examined. Mixtures of asphaltene (As) and iron compounds (FeS, α-Fe2O3) were thermally treated at 365°C for 8 h. Approximately 60 % of toluene-insoluble fractions were recovered from As with and without iron compounds. The fractions were investigated by elemental analysis, LDI/TOF/MS and IR. The average molecular models of the fractions were determined using these measured data. The models of the fractions prepared from As/-, As/FeS and As/Fe2O3 showed polyaromatic structure. The number of aromatic rings of the fraction prepared from As/Fe2O3 was slightly larger than that of the fractions prepared from As/- and As/FeS. This result suggested lattice oxygen of α-Fe2O3 proceeded thermal decomposition and condensation reaction of As.

構造・物性、カーボンリサイクル、その他
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バイオマス2
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