Experimental Study of Syngas Generated from Biomass Pellet in an Interconnected Fluidized-bed Gasifier 6 June 2018 Session 22: Pilot-plants & operations (2) 10:00 – 10:20 Presenter: Yau-Pin Chyou, Ph. D. Institute of Nuclear Energy Research (INER) Co-Authors: Wei-Chun Chang, Yin-Ching Tung, Po-Chuang Chen, Rei-Yu Chein, Kung-Tung Wu*
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Experimental Study of Syngas Generated
from Biomass Pellet in an Interconnected
Fluidized-bed Gasifier
6 June 2018
Session 22: Pilot-plants & operations (2)
10:00 – 10:20
Presenter: Yau-Pin Chyou, Ph. D.
Institute of Nuclear Energy Research (INER)
Co-Authors: Wei-Chun Chang, Yin-Ching Tung,
Po-Chuang Chen, Rei-Yu Chein,
Kung-Tung Wu*
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Outlines
Introduction INER’s Mission
Motivation: Indirect Gasification
Interconnected Fluidized-Bed (IFB) Concept of IFB
History of IFB Development
Experimental System Configuration
Feedstock
Testing Parameters
Results Bed Temperature in the Gasification zone
Gas Velocity
Bed Temperature in the Combustion zone
Tar Content
Summary and Future Work Source: http://maps.google.com/,
History: founded since 1968 and currently under the administration of Atomic Energy Council (AEC).
Mission: the sole national research institute, dedicated to energy technologies R&D and promotion for peaceful applications of nuclear science in Taiwan.
Location: in Longtan District, Taoyuan City, ~30 miles SW away from Taipei City (about 1 hour drive), in scenic and historic suburban surroundings close to the Shihmen Reservoir.
• Parameters kept constant – Gas velocity in dense bed
– Equivalence Ratio (ER)
– The effect of ER will be conducted
in further work
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Condition Parameters
Temperature (°C) 700, 750, 800
Dimensionless Gas velocity in
lean bed (U/Umf)2, 3, 4
Dimensionless Gas velocity in
dense bed (Udb/Umf)1.1
Equivalence Ratio (ER) 0.2
U: gas velocity
Umf: minimum fluidization velocity
Results - Bed Temperature-Gasification (1/3)
• Effect of bed temperature on syngas composition in the
gasification zone
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U / Umf = 2– Temperature
• CO, H2
• CO2, CH4,
• CnHm
– The increase amount of CO/H2 seems to be associated with the decomposition of CH4, CnHm
Results-Bed Temperature-Gasification(3/3)
• Effect of bed temperature on syngas composition in the
gasification zone
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– Temperature • CO, H2
• CO2, CH4, CnHm
– The trend of lower residence time case (U/Umf = 4) is similar to that of higher one (U/Umf = 2)
– Effect of temperature on the CnHm content in the former is more sensitive than that in the latter
U / Umf = 4
Results - Bed Temperature-Gasification (2/3)
• Effect of bed temperature on syngas composition in the
gasification zone
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– Temperature • CO
• H2
• CO2
• CH4
• CnHm
– Inconsistent data in the Case with
750°C
– More study is needed to reexamine the
inconsistency of gas composition at
750°C
U / Umf = 3
Results - Gas Velocity (1/2)
• Effect of gas velocity on syngas composition in the
gasification zone
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– Gas velocity
• CO, CH4, H2
• CO2, CnHm
• Higher gas velocity enhances
the mixing phenomena,
• three reactions are enhanced to
increase the yield of CO and H2
700 °C
CH4 + CO2 → 2CO + 2H2
CnHm + nH2O → 2nCO + ( m/2)H2
C + H2O → CO + H2
Results-Gas Velocity(2/2)
• Effect of gas velocity on syngas composition in the
gasification zone
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– Gas velocity
• CO, CH4, H2
• CO2, CnHm
• Higher
– Highest CO and H2 could be
found at 800°C and U/Umf = 4
– Higher temperature (900°C) tests
will be conducted in further work to
check the gasification performance
800 °C
Results - Bed Temperature-Combustion
• Effect of bed temperature on gas composition in the
combustion zone
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U / Umf = 2 U / Umf = 3 U / Umf = 4
• CO2 concertation is detected in all cases Char (unburmed carbon)
from gasification zone is converted into CO2
– heat is released via combustion (exothermic reaction)
– Then, energy is transferred for gasification (endothermic reaction).
Summary and Future Work (1/2)
• IFB is verified to be employed in gasification application
• The major trend shows that the contents of valuable gases insyngas increase with the temperature and gas velocity
• Gas composition in the combustion zone shows the residue of carbon content is converted to CO2, and the energy used to heat up the bed material– To recover the energy and increase the gasification efficiency
– The IFB could be applied as the indirect gasification with adopting steam as gasified agent
• Effect of temperature and gas velocity on tar content is inconsistent,further study is needed to investigate the issue
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Summary and Future Work (2/2)
• Effect of operation parameters– Temperature be increased to 900°C (this study: 700°C~800°C)
– Equivalence ratio (ER) be increased to 0.4 (this study: 0.2)
• Effect of geometry– The height of the reactor will be extended, to investigate the effect on
tar content and syngas composition
• Effect of gasified agent– Pure steam gasification to yield the syngas with N2-free product
– Metal oxides used as bed material to provide the O2, to crack the tar, and other function based on the type of metal oxides
– Trace gas will be adopted in the gasified agent to check the separation of the two gases in the two reaction zones
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Yau-Pin CHYOU, Ph. D. Clean Carbon as Sustainable Energy (CaSE) Program