Kinetics and Mechanism of Steam Gasification of Char from Hydrothermally Treated Woody Biomass

Bai, Lei; Karnowo, -; Kudo, Shinji; Norinaga, Koyo; Wang, Yangang; Hayashi, Jun Ichiro

doi:10.1021/ef501898h

Cited by 35 publications

(31 citation statements)

References 56 publications

(87 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hydrothermal extraction is based on the theory that subcritical water can dissolve organic matter. The reaction is carried out in a special closed container with hot-compressed water above 100 • C [36], and undissolvable/insoluble substances are dissolved in aqueous medium [37]. Elemental analysis and spectroscopic methods including UV-VIS and FTIR spectroscopy are usually used for the characterization of HAs.…”

Section: Introductionmentioning

confidence: 99%

Extraction of Humic Acid from Lignite by KOH-Hydrothermal Method

et al. 2019

View full text Add to dashboard Cite

Humic acid (HA) was extracted by a hydrothermal method from Huolinhe lignite from Inner Mongolia. The effects of the alkali-to-carbon mass ratio, water-to-coal mass ratio, reaction temperature, and reaction time on the HA yield were investigated. The physicochemical characterization of the products was performed, and the reaction mechanism was explored. Raw coal, HA, and residual coal were characterized using Fourier-transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–VIS), elemental composition, and X-ray diffraction (XRD) analyses and compared to each other. The maximum HA yield (90.2%) was obtained from the 0.250–0.180 mm size fraction of the coal sample at a reaction temperature and time of 190 °C and 7 h. Proximate analysis proved that the ash and sulfur of lignite can be removed by hydrothermal treatment. Elemental analysis showed that the O/C and H/C ratios were highest for HA, followed by those for residual coal and raw coal, indicating an increase in the oxygen and hydrogen content of HA. FTIR and UV–VIS analyses showed that hydrothermal extraction destroyed the macromolecular structure of lignite. Moreover, the organics were degraded and hydrolyzed during the reaction process.

show abstract

Section: Introductionmentioning

confidence: 99%

Extraction of Humic Acid from Lignite by KOH-Hydrothermal Method

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Yilmaz et al presented a detailed thermodynamic performance assessment of an integrated system based on gasification for generation of cooling, heating, hydrogen, electricity and freshwater [22]. Bai et al deepened kinetics and mechanisms of steam gasification from woody biomass treated with a hydrothermal process [23]. Huang et al analyzed the effects of water content and particle size on pyrolysis and gasification of lignite chars [24].…”

Section: Introductionmentioning

confidence: 99%

Influence of Oxidant Agent on Syngas Composition: Gasification of Hazelnut Shells through an Updraft Reactor

Gallucci¹,

Liberatore

Sapegno

et al. 2019

Energies

View full text Add to dashboard Cite

This work aims to study the influence of an oxidant agent on syngas quality. A series of tests using air and steam as oxidant agents have been performed and the results compared with those of a pyrolysis test used as a reference. Tests were carried out at Sapienza University of Rome, using an updraft reactor. The reactor was fed with hazelnut shells, waste biomass commonly available in some parts of Italy. Temperature distribution, syngas composition and heating value, and producible energy were measured. Air and steam gasification tests produced about the same amount of syngas flow, but with a different quality. The energy flow in air gasification had the smallest measurement during the experiments. On the contrary, steam gasification produced a syngas flow with higher quality (13.1 MJ/Nm3), leading to the best values of energy flow (about 5.4 MJ/s vs. 3.3 MJ/s in the case of air gasification). From the cold gas efficiency point of view, steam gasification is still the best solution, even considering the effect of the enthalpy associated with the steam injected within the gasification reactor.

show abstract

“…Nevertheless, supercritical water coal gasification operates over 20 MPa and may result in a higher cost for the gasifier. There are some publications relative to the topic of hydrogen production through steam gasification of coal, char, and biomass [19][20][21][22][23]. Herein, thermodynamic and kinetic analysis are presented.…”

Section: Introductionmentioning

confidence: 99%

Experimental Study and Thermodynamic Analysis of Hydrogen Production through a Two-Step Chemical Regenerative Coal Gasification

2019

Applied Sciences

View full text Add to dashboard Cite

Hydrogen, as a strategy clean fuel, is receiving more and more attention recently in China, in addition to the policy emphasis on H2. In this work, we conceive of a hydrogen production process based on a chemical regenerative coal gasification. Instead of using a lumped coal gasification as is traditional in the H2 production process, herein we used a two-step gasification process that included coking and char-steam gasification. The sensible heat of syngas accounted for 15–20% of the total energy of coal and was recovered and converted into chemical energy of syngas through thermochemical reactions. Moreover, the air separation unit was eliminated due to the adoption of steam as oxidant. As a result, the efficiency of coal to H2 was enhanced from 58.9% in traditional plant to 71.6% in the novel process. Further, the energy consumption decreased from 183.8 MJ/kg in the traditional plant to 151.2 MJ/kg in the novel process. The components of syngas, H2, and efficiency of gasification are herein investigated through experiments in fixed bed reactors. Thermodynamic performance is presented for both traditional and novel coal to hydrogen plants.

show abstract

Kinetics and Mechanism of Steam Gasification of Char from Hydrothermally Treated Woody Biomass

Cited by 35 publications

References 56 publications

Extraction of Humic Acid from Lignite by KOH-Hydrothermal Method

Extraction of Humic Acid from Lignite by KOH-Hydrothermal Method

Influence of Oxidant Agent on Syngas Composition: Gasification of Hazelnut Shells through an Updraft Reactor

Experimental Study and Thermodynamic Analysis of Hydrogen Production through a Two-Step Chemical Regenerative Coal Gasification

Contact Info

Product

Resources

About