Structural characteristics and thermal conversion performance of ash and slag from circulating fluidized bed gasifier

HU Xiao-bo; YANG Xiao-qin; MO Wen-long; ZHANG Shu-pei; GAO Ji; WEI Xian-yong; FAN Xing

doi:10.1016/S1872-5813(22)60024-0

Volume 50 Issue 10

Oct. 2022

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Article Navigation > Journal of Fuel Chemistry and Technology > 2022 > 50(10): 1361-1370

HU Xiao-bo, YANG Xiao-qin, MO Wen-long, ZHANG Shu-pei, GAO Ji, WEI Xian-yong, FAN Xing. Structural characteristics and thermal conversion performance of ash and slag from circulating fluidized bed gasifier[J]. Journal of Fuel Chemistry and Technology, 2022, 50(10): 1361-1370. doi: 10.1016/S1872-5813(22)60024-0

Citation:

HU Xiao-bo, YANG Xiao-qin, MO Wen-long, ZHANG Shu-pei, GAO Ji, WEI Xian-yong, FAN Xing. Structural characteristics and thermal conversion performance of ash and slag from circulating fluidized bed gasifier[J]. Journal of Fuel Chemistry and Technology, 2022, 50(10): 1361-1370. doi: 10.1016/S1872-5813(22)60024-0

Citation:

HU Xiao-bo, YANG Xiao-qin, MO Wen-long, ZHANG Shu-pei, GAO Ji, WEI Xian-yong, FAN Xing. Structural characteristics and thermal conversion performance of ash and slag from circulating fluidized bed gasifier[J]. Journal of Fuel Chemistry and Technology, 2022, 50(10): 1361-1370. doi: 10.1016/S1872-5813(22)60024-0

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Structural characteristics and thermal conversion performance of ash and slag from circulating fluidized bed gasifier

doi: 10.1016/S1872-5813(22)60024-0

HU Xiao-bo^1
,,
YANG Xiao-qin²,
MO Wen-long^{1
,
,},
ZHANG Shu-pei²,
GAO Ji¹,
WEI Xian-yong^{1, 3},
FAN Xing^{1, 4}

1.
State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources and Key Laboratory of Coal Clean Conversion & Chemical Engineering Process (Xinjiang Uyghur Autonomous Region), School of Chemical Engineering and Technology, Xinjiang University, Urumqi 830046, China
2.
Xinjiang Yihua Chemical Industry Co., Ltd., Changji 831700, China
3.
Key Laboratory of Coal Processing and Efficient Utilization, Ministry of Education, China University of Mining and Technology, Xuzhou 221116, China
4.
College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao 266590, China

Funds: The project was supported by High Quality Development Special Project for Science and Technology Supporting Industry from Changji, Xinjiang, China (2022Z04) "Research, Development and Application of Key Technologies for Improving Quality and Efficiency in Coal Chemical Industry", Special Project from the State Key Laboratory of Chemistry and Utilization of Carbon based Energy Resources "Element Migration and Transformation Mechanism and Reactor Simulation and Optimization of Fluidized Bed Gasifier Based on Zhundong coal", Research and Development on Comprehensive Utilization of Solid Waste in Xinjiang Yihua Circulating Fluidized Bed Coal Gasification Process, Optimization and Demonstration of Circulating Fluidized Bed Gasification Process of High Alkali and Low Ash Melting Point Coal of Xinjiang Yihua

Received Date: 2022-03-16
Accepted Date: 2022-04-18
Rev Recd Date: 2022-04-17

Available Online: 2022-05-05

Publish Date: 2022-10-31

Abstract

Abstract

Based on the circulating fluidized bed (CFB), Xinjiang Zhundong coal (ZDC) gasification ash (FA: fly ash; BA: bottom slag) was analyzed by industrial analysis, ultimate analysis and Fourier infrared spectroscopy to determine the basic properties and functional group species. The results show that BA contains up to 99.30% in ash, while FA shows high fixed carbon and C content of 69.30% and 73.78% respectively. Furthermore, the carbonaceous forms and surface morphology of ZDC and FA were characterized by Raman, XRPES and SEM, and the pyrolysis, combustion and gasification characteristics of ZDC and FA were studied with TG-DTG methods. XRPES show that C content of the FA surface is 89.42%, and exists primarily as >C–C< and >C–H, while O was in the form of >C=O. Alkaline earth metals Ca bound to the above-mentioned carbon-involved functional groups cause high disorder in FA. SEM observed that the rough and porous FA surface occurs due to spherical particles of molten mineral attached and embedded surface and pore channels. The thermal conversion characteristics show that the maximum weight loss rate peak temperature of pyrolysis and combustion of FA is significantly higher than that of ZDC, indicating that the pyrolysis and combustion performance of FA is reduced. However, 100% carbon conversion of FA uses about half the time compared with ZDC and the gasification performance has improved significantly since it has well-developed pore structures, more amorphous carbon and abundant active sites, enhancing diffusion of CO₂ from gasifiers. Briefly, FA has the potential and ability to be recycled for direct utilization in CFB as gasification feed.
- coal gasification,
- zhundong coal,
- ash and slag,
- composition structure,
- thermal conversion

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References(37)

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