Evolution of Fly Ash Aluminosilicates in Slagging Deposition during Oxy-Coal Combustion Investigated by Al-27 Magic Angle Spinning Nuclear Magnetic Resonance

doi:10.1021/acs.energyfuels.8b02812

	Evolution of Fly Ash Aluminosilicates in Slagging Deposition during Oxy-Coal Combustion Investigated by Al-27 Magic Angle Spinning Nuclear Magnetic Resonance
	Chen, Lei 1; Zhan, Zhonghua 2,3,4; Tian, Sida 5
刊名	ENERGY & FUELS
	2018-12-01
卷号	32 期号:12 页码:12896-12904
ISSN号	0887-0624
DOI	10.1021/acs.energyfuels.8b02812
英文摘要	Boiler slagging jeopardizes the safe and economic operation of coal-fired boilers. Aluminosilicates are the most abundant substances in fly ash and boiler slagging deposits. In order to understand the roles of the fly ash aluminosilicates in slagging, studying their evolution in the ash deposition is invaluable. In this work,Al- 27 magic angle spinning nuclear magnetic resonance (MAS-NMR) and X-ray diffraction were used to measure the aluminum coordination and the phase distribution in fly ash and ash deposit samples of two USA thermal coals [Powder River Basin (PRB) sub-bituminous coal and Illinois coal] and their blended coal prepared in an oxy-coal combustion experiment apparatus. Morphology and constituents of these samples were also analyzed using scanning electronic microscopy. The results show that, for all fly ashes and ash deposits, the aluminum exists only in aluminosilicates and is mainly four-coordinate aluminum [Al(IV)], with a small amount in six-coordinate aluminum Al(VI) (chemical shift: 2.8 ppm). The formation of spinning sidebands due to the paramagnetic effect of the Fe-bearing species in fly ash increases difficulty in resolving the NMR spectra of fly ash aluminosilicates. The aluminosilicates in the PRB coal fly ash are mainly amorphous and also contain low-crystallinity gehlenite; the aluminosilicates in the Illinois coal fly ash are basically amorphous, and the Fe-containing materials in the fly ash generate stronger spinning sidebands of Al(V) in its Al-27 MAS-NMR spectra. During ash deposition, the evolutions of fly ash aluminosilicates for the coals are different. For PRB coal, fly ash aluminosilicates hardly react with foreign active metal elements after being deposited on a deposition probe in the furnace, even though the fly ash contains a large amount of calcium. For the Illinois coal, the easily melting aluminosilicates in ash deposition increase. The ash deposition for the blended coal demonstrates that the easily melting aluminosilicates in fly ash continue to combine with foreign iron and calcium ions in the ash deposition process, which can deteriorate the ash deposition. Therefore, the easily melting aluminosilicates should receive more attention for the understanding and control of slagging.
资助项目	National Science Foundation of China[51376061] ; Illinois Clean Coal Institute (ICCI Project)[14/SA-2] ; State of Wyoming under the Clean Coal Research Program[1100-20268] ; China Scholarship Council
WOS关键词	SOLID-STATE NMR ; SI-29 ; ALUMINUM ; MULLITE
WOS研究方向	Energy & Fuels ; Engineering
语种	英语
出版者	AMER CHEMICAL SOC
WOS记录号	WOS:000454567000087
资助机构	National Science Foundation of China ; National Science Foundation of China ; Illinois Clean Coal Institute (ICCI Project) ; Illinois Clean Coal Institute (ICCI Project) ; State of Wyoming under the Clean Coal Research Program ; State of Wyoming under the Clean Coal Research Program ; China Scholarship Council ; China Scholarship Council ; National Science Foundation of China ; National Science Foundation of China ; Illinois Clean Coal Institute (ICCI Project) ; Illinois Clean Coal Institute (ICCI Project) ; State of Wyoming under the Clean Coal Research Program ; State of Wyoming under the Clean Coal Research Program ; China Scholarship Council ; China Scholarship Council ; National Science Foundation of China ; National Science Foundation of China ; Illinois Clean Coal Institute (ICCI Project) ; Illinois Clean Coal Institute (ICCI Project) ; State of Wyoming under the Clean Coal Research Program ; State of Wyoming under the Clean Coal Research Program ; China Scholarship Council ; China Scholarship Council ; National Science Foundation of China ; National Science Foundation of China ; Illinois Clean Coal Institute (ICCI Project) ; Illinois Clean Coal Institute (ICCI Project) ; State of Wyoming under the Clean Coal Research Program ; State of Wyoming under the Clean Coal Research Program ; China Scholarship Council ; China Scholarship Council
内容类型	期刊论文
源URL	[http://ir.wipm.ac.cn/handle/112942/13868]
专题	中国科学院武汉物理与数学研究所
通讯作者	Tian, Sida
作者单位	1.Chinese Acad Sci, Wuhan Inst Phys & Math, Natl Ctr Magnet Resonance Wuhan, State Key Lab Magnet Resonance & Atom & Mol Phys, Wuhan 430071, Hubei, Peoples R China 2.React Engn Int, 746 E Winchester St,Suite 120, Murray, UT 84107 USA 3.Univ Utah, Inst Clean & Secure Energy, 50 South Cent Campus Dr, Salt Lake City, UT 84112 USA 4.Univ Utah, Dept Chem Engn, 50 South Cent Campus Dr, Salt Lake City, UT 84112 USA 5.North China Elect Power Univ, Sch Energy Power & Mech Engn, Minist Educ, Key Lab Condit Monitoring & Control Power Plant E, Beijing 102206, Peoples R China
推荐引用方式 GB/T 7714	Chen, Lei,Zhan, Zhonghua,Tian, Sida. Evolution of Fly Ash Aluminosilicates in Slagging Deposition during Oxy-Coal Combustion Investigated by Al-27 Magic Angle Spinning Nuclear Magnetic Resonance[J]. ENERGY & FUELS,2018,32(12):12896-12904.
APA	Chen, Lei,Zhan, Zhonghua,&Tian, Sida.(2018).Evolution of Fly Ash Aluminosilicates in Slagging Deposition during Oxy-Coal Combustion Investigated by Al-27 Magic Angle Spinning Nuclear Magnetic Resonance.ENERGY & FUELS,32(12),12896-12904.
MLA	Chen, Lei,et al."Evolution of Fly Ash Aluminosilicates in Slagging Deposition during Oxy-Coal Combustion Investigated by Al-27 Magic Angle Spinning Nuclear Magnetic Resonance".ENERGY & FUELS 32.12(2018):12896-12904.