Development of a high‐temperature two‐stage entrained flow gasifier model for the process of biomass gasification and syngas formation

2019 ◽  
Vol 43 (11) ◽  
pp. 5864-5878 ◽  
Author(s):  
Mohammad‐Ali Yazdanpanah Jahromi ◽  
Kazem Atashkari ◽  
Mohammad Kalteh
Keyword(s):  
High Temperature ◽  
Biomass Gasification ◽  
Two Stage ◽  
Entrained Flow ◽  
Entrained Flow Gasifier

scholarly journals Investigation of the Coal Gasification Process Under Various Operating Conditions Inside a Two-Stage Entrained Flow Gasifier

2012 ◽  
Vol 4 (2) ◽  
Author(s):  
Armin Silaen ◽  
Ting Wang
Keyword(s):  
Coal Gasification ◽  
Operating Conditions ◽  
Coal Slurry ◽  
Two Stage ◽  
Heating Value ◽  
Fuel Distribution ◽  
Entrained Flow ◽  
One Stage ◽  
Gasification Process ◽  
Entrained Flow Gasifier

Numerical simulations of the coal gasification process inside a generic 2-stage entrained-flow gasifier fed with Indonesian coal at approximately 2000 metric ton/day are carried out. The 3D Navier–Stokes equations and eight species transport equations are solved with three heterogeneous global reactions, three homogeneous reactions, and two-step thermal cracking equation of volatiles. The chemical percolation devolatilization (CPD) model is used for the devolatilization process. This study is conducted to investigate the effects of different operation parameters on the gasification process including coal mixture (dry versus slurry), oxidant (oxygen-blown versus air-blown), and different coal distribution between two stages. In the two-stage coal-slurry feed operation, the dominant reactions are intense char combustion in the first stage and enhanced gasification reactions in the second stage. The gas temperature in the first stage for the dry-fed case is about 800 K higher than the slurry-fed case. This calls for attention of additional refractory maintenance in the dry-fed case. One-stage operation yields higher H2, CO and CH4 combined than if a two-stage operation is used, but with a lower syngas heating value. The higher heating value (HHV) of syngas for the one-stage operation is 7.68 MJ/kg, compared with 8.24 MJ/kg for two-stage operation with 75%–25% fuel distribution and 9.03 MJ/kg for two-stage operation with 50%–50% fuel distribution. Carbon conversion efficiency of the air-blown case is 77.3%, which is much lower than that of the oxygen-blown case (99.4%). The syngas heating value for the air-blown case is 4.40 MJ/kg, which is almost half of the heating value of the oxygen-blown case (8.24 MJ/kg).

scholarly journals Experimental Study on Coal Gasification in a Full-Scale Two-Stage Entrained-Flow Gasifier

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4937
Author(s):  
Guangyu Li ◽  
Luping Wang ◽  
Chaowei Wang ◽  
Chang’an Wang ◽  
Ping Wu ◽  
...  
Keyword(s):  
Experimental Study ◽  
Coal Gasification ◽  
Full Scale ◽  
Input Rate ◽  
Two Stage ◽  
Entrained Flow ◽  
Operation Period ◽  
Entrained Flow Gasifier ◽  
Coal Resource ◽  
First Time

In this paper, coal gasification characteristics in the reductor were investigated in a full-scale two-stage pressurized entrained-flow gasifier, which has been seldom conducted previously. The present study aimed at elucidating the effects of gasifying agent concentration, coal input rate, and operation period under full reductor load on the performance of a utility two-stage pressurized entrained-flow gasifier for the first time. When the steam input in the combustor was raised from 3318 kg/h to 5722 kg/h, the total outputs of H2, CO, and CO2 were increased by 1765 Nm3/h and 2063 Nm3/h, respectively, while the CH4 output was decreased by 49 Nm3/h. The coal conversion rate was minimal at low steam input. In addition, more coal gasified in the reductor could increase the output of CH4, while CH4 could reach 1.24% with the coal input in the range of 8000–10,000 kg/h. The present work can offer a further understanding of the gasification performance in the reductor of the full-scale two-stage pressurized entrained-flow gasifier, and motivates the potential for clean utilization of coal resource.

Biomass–oxygen gasification in a high-temperature entrained-flow gasifier

2009 ◽  
Vol 27 (5) ◽  
pp. 606-611 ◽  
Author(s):  
Jinsong Zhou ◽  
Qing Chen ◽  
Hui Zhao ◽  
Xiaowei Cao ◽  
Qinfeng Mei ◽  
...  
Keyword(s):  
High Temperature ◽  
Entrained Flow ◽  
Entrained Flow Gasifier

Review of Coal-to-Synthetic Natural Gas (SNG) Production Methods and Modeling of SNG Production in an Entrained-Flow Gasifer

2016 ◽  
Author(s):  
Xijia Lu ◽  
Ting Wang
Keyword(s):  
High Temperature ◽  
Computational Model ◽  
Catalytic Reaction ◽  
Reaction Rates ◽  
Sensitivity Study ◽  
Synthetic Natural Gas ◽  
Entrained Flow ◽  
Methanation Reaction ◽  
Gasification Process ◽  
Entrained Flow Gasifier

In this paper, the coal-to-synthetic natural gas (SNG) technologies have been reviewed. Steam-oxygen gasification, hydrogasification, and catalytic steam gasification are the three major gasification processes used in coal-to-SNG production. So far, only the steam-oxygen gasification process is commercially proven by installing a catalytic methanation reactor downstream of the gasification process after syngas is produced, cleaned, and shifted to achieve an appropriate H2/CO ratio for methanation reaction. This process is expensive, less efficient, and time consuming. Ideally, it will be more effective and economic if methanation could be completed in an once-through entrained-flow gasifier. Technically, this idea is challenging because an effective gasification process is typically operated in a high-pressure and high-temperature condition, which is not favorable for methanation reaction, which is exothermic. To investigate this idea, a computational model is established and a sensitivity study of methanation reactions with and without catalysts are conducted in this study. In modeling the methanation process in a gasifier, correct information of the reaction rates is extremely important. Most of known methanation reaction rates are tightly linked to the catalysts used. Since the non-catalytic reaction rates for methanation are not known in a gasifer and the issues are compounded by the fact that inherent minerals in coal ashes can also affect the methanation kinetics, modeling of methanation in an entrained-flow gasifier becomes very challenging. Considering these issues, instead of trying to obtain the correct methnation reaction rate, this study attempts to use computational model as a convenient tool to investigate the sensitivity of methane production under a wide range methanation reaction rates with and without catalysts. From this sensitivity study, it can be learned that the concept of implementing direct methanation in a once-through entrained-flow gasifier may not be attractive due to competitions of other reactions in a high-temperature environment. The production of SNG is limited to about 18% (vol) with catalytic reaction with a pre-exponential factor A in the order of 107. A further increase of the value of A to 1011 doesn’t result in more production of SNG. This SNG production limit could be caused by the high-temperature and short residence time (3–4 seconds) in the entraind-flow gasifier.

scholarly journals Optimization of the Three-stage Biomass Gasification Characteristics in High-temperature Entrained-flow Bed

BioResources ◽  
2014 ◽  
Vol 9 (2) ◽  
Author(s):  
Chao Chen ◽  
Chunjiang Yu ◽  
Jinsong Zhou ◽  
Yangyang Xiang ◽  
Zhongyang Luo
Keyword(s):  
High Temperature ◽  
Biomass Gasification ◽  
Entrained Flow

Numerical analysis on the influential factors of coal gasification performance in two-stage entrained flow gasifier

2017 ◽  
Vol 112 ◽  
pp. 1601-1611 ◽  
Author(s):  
Lijun Wang ◽  
YiJun Jia ◽  
Sunel Kumar ◽  
Rundong Li ◽  
Rasool Bux Mahar ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Coal Gasification ◽  
Influential Factors ◽  
Two Stage ◽  
Entrained Flow ◽  
Entrained Flow Gasifier
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