Study on the enhancement of hydrogen generation via biomass gasification in fluidizedbed reactors

In this study, solid biomass is gasified in fluidized-bed reactors, to investigate the effect of various means on syngas composition, especially for enhancing hydrogen content in the production gas. Conventionally, air is supplied to the reactor as gasification medium, which inevitably results in a high nitrogen content in the syngas. Alternatively, steam or oxygen-rich gas can be supplied to improve the syngas characteristics. On the other hand, a so-called “indirect gasification technology” realizes the whole conversion processes in dual reactors, for combustion and gasification, respectively; moreover, solid materials are circulated through two reactors, while gaseous streams in between are separated from each other. Hence, this system features the advantage of producing near nitrogen-free syngas in the gasifier, with air as oxidant in the combustor. Baseline experiments with various operating parameters, including air equivalence ratio (ER) and temperature, were firstly performed in a 30 kWth bubbling fluidized-bed gasifier; then, trial tests were conducted with the aforementioned operational and constructional factors. The preliminary test data show positive trends for the enhancement of hydrogen generation via biomass gasification. Further efforts will be pursued to establish a data base, which would be beneficial to extensive researches on clean energy and carbon abatement technologies.

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Development of Biomass Gasification Technology with Fluidized-Bed Reactors for Enhancing Hydrogen Generation: Part I, Hydrodynamic Characterization of Dual Fluidized-Bed Gasifiers

Applied Sciences ◽

10.3390/app10010002 ◽

2019 ◽

Vol 10 (1) ◽

pp. 2 ◽

Cited By ~ 4

Author(s):

Yau-Pin Chyou ◽

Der-Ming Chang ◽

Po-Chuang Chen ◽

Hsiu-Yun Chien ◽

Keng-Tung Wu ◽

...

Keyword(s):

Fluidized Bed ◽

Hydrogen Generation ◽

Clean Energy ◽

Chemical Conversion ◽

Biomass Gasification ◽

Experimental Results ◽

Hydrodynamic Characteristics ◽

Fluidized Bed Reactors ◽

Cold Model ◽

Gasification Technology

Various means for enhancing hydrogen content in the syngas from gasification of solid biomass in fluidized-bed reactors were investigated in this study. Steam or oxygen-rich gas can be supplied as gasification medium, to improve the syngas characteristics. Alternatively, a so-called “indirect gasification technology” realizes the thermo-chemical conversion processes in dual reactors, respectively, for combustion and gasification, where gaseous streams in between are separated while solid materials are circulated through. Hence, with air as oxidant for combustion this system features the advantage of producing nearly nitrogen-free syngas. Baseline experiments were firstly carried out to identify performance features; then, parametric studies were conducted and positive trends for enhancing hydrogen generation via biomass gasification were revealed. Moreover, hydrodynamic characteristics in dual reactors were comprehensively envisaged in the cold-flow models to facilitate subsequent investigation into thermo-chemical processes. The experimental results indicated that the circulation mass of the bed material driven by the operating air exceeded the design value, which gave a comfortable safety factor of the engineering design. In addition, the average pressure distribution measured by the cyclic operation of the system was similar to that of the published literature. Based on the experimental results of the cold model, the suggestions of the operating tests in the hot model were addressed. Further efforts will be pursued to establish databases for clean energy and carbon abatement technologies.

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Investigation into fluctuating anisotropy for biomass gasification in bubbling fluidized bed gasifier

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2018.01.014 ◽

2018 ◽

Vol 138 ◽

pp. 774-782 ◽

Cited By ~ 2

Author(s):

Juhui Chen ◽

Xiao Shi ◽

Shuai Wang ◽

Jiahao Li ◽

Ting Hu ◽

...

Keyword(s):

Fluidized Bed ◽

Biomass Gasification ◽

Bubbling Fluidized Bed ◽

Fluidized Bed Gasifier

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Investigation of syngas exergy value and hydrogen concentration in syngas from biomass gasification in a bubbling fluidized bed gasifier by using machine learning

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2021.03.184 ◽

2021 ◽

Author(s):

Senem Sezer ◽

Uğur Özveren

Keyword(s):

Machine Learning ◽

Fluidized Bed ◽

Hydrogen Concentration ◽

Biomass Gasification ◽

Bubbling Fluidized Bed ◽

Fluidized Bed Gasifier

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Second Law Analysis of Bubbling Fluidized Bed Gasifier for Biomass Gasification

Progress in Biomass and Bioenergy Production ◽

10.5772/16912 ◽

2011 ◽

Author(s):

Babak Fakhim ◽

Bijan Farhanieh

Keyword(s):

Fluidized Bed ◽

Biomass Gasification ◽

Second Law ◽

Second Law Analysis ◽

Bubbling Fluidized Bed ◽

Fluidized Bed Gasifier

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Experimental Evaluation of Napier Grass Gasification in an Autothermal Bubbling Fluidized Bed Reactor

Energies ◽

10.3390/en12081517 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1517 ◽

Cited By ~ 4

Author(s):

Ramin Khezri ◽

Wan Azlina Wan Ab Karim Ghani ◽

Dayang Radiah Awang Biak ◽

Robiah Yunus ◽

Kiman Silas

Keyword(s):

Fluidized Bed ◽

High Performance ◽

Maximum Yield ◽

Substantial Effect ◽

Napier Grass ◽

Small Scale ◽

Fluidized Bed Reactors ◽

Direct Combustion ◽

Bubbling Fluidized Bed ◽

Fluidized Bed Gasifier

Air gasification of Napier grass (NG) was studied with the target of producing combustible synthesis gas to be used in direct combustion for power generation. A small-scale autothermal bubbling fluidized bed gasifier was used to investigate the effect of reactor temperature, equivalence ratio (ER), and static bed height (SBH) on gasification performance and combustibility of the producer gas. The main generated species in syngas were identified through gas chromatography (GC) analysis. Minimum fluidization conditions were determined at different levels of SBH. Experiments carried out with two intentions of first, to achieve the highest composition of combustible species to ensure the maximum Lower Heating Value (LHV) of syngas and second, to obtain a high performance process with maximum yield of syngas and minimum residues. The results showed that the temperature and ER have significant effects on syngas yield and composition. SBH was found have a substantial effect on the production of H2 and CO. The results from this study was compared to other gasification studies from literature which have evaluated biomass gasification in bubbling fluidized bed reactors with different scales but almost similar method of experimentation. The purpose of verification was to demonstrate the effect of different reactor scales and heating characteristics on the results.

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Hydrogen Production by Fluidized Bed Reactors: A Quantitative Perspective Using the Supervised Machine Learning Approach

J ◽

10.3390/j4030022 ◽

2021 ◽

Vol 4 (3) ◽

pp. 266-287

Author(s):

Zheng Lian ◽

Yixiao Wang ◽

Xiyue Zhang ◽

Abubakar Yusuf ◽

Lord Famiyeh ◽

...

Keyword(s):

Machine Learning ◽

Hydrogen Production ◽

Fluidized Bed ◽

Biomass Gasification ◽

Supervised Machine Learning ◽

Fluidized Bed Reactors ◽

Hydrogen Yield ◽

Carbon Conversion ◽

Operational Parameters ◽

Operational Conditions

The current hydrogen generation technologies, especially biomass gasification using fluidized bed reactors (FBRs), were rigorously reviewed. There are involute operational parameters in a fluidized bed gasifier that determine the anticipated outcomes for hydrogen production purposes. However, limited reviews are present that link these parametric conditions with the corresponding performances based on experimental data collection. Using the constructed artificial neural networks (ANNs) as the supervised machine learning algorithm for data training, the operational parameters from 52 literature reports were utilized to perform both the qualitative and quantitative assessments of the performance, such as the hydrogen yield (HY), hydrogen content (HC) and carbon conversion efficiency (CCE). Seven types of operational parameters, including the steam-to-biomass ratio (SBR), equivalent ratio (ER), temperature, particle size of the feedstock, residence time, lower heating value (LHV) and carbon content (CC), were closely investigated. Six binary parameters have been identified to be statistically significant to the performance parameters (hydrogen yield (HY)), hydrogen content (HC) and carbon conversion efficiency (CCE)) by analysis of variance (ANOVA). The optimal operational conditions derived from the machine leaning were recommended according to the needs of the outcomes. This review may provide helpful insights for researchers to comprehensively consider the operational conditions in order to achieve high hydrogen production using fluidized bed reactors during biomass gasification.

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