Application of vermiculite and limestone to desulphurization and to the   removal of dust during briquette combustion

doi:10.1180/0026461036760162

CORC > 北京大学 > 地球与空间科学学院

	Application of vermiculite and limestone to desulphurization and to the removal of dust during briquette combustion
	Lu, A ; Zhao, D ; Li, J ; Wang, C ; Qin, S
刊名	mineralogical magazine
	2003
关键词	coal desulphurization dust removal air pollution vermiculite CaCO3 briquette ash China COAXIAL CYLINDERS IMPINGING STREAMS SO2 ABSORPTION GASIFICATION SULFATION SORBENTS BEHAVIOR GAS BED
DOI	10.1180/0026461036760162
英文摘要	Small domestic cooking furnaces are widely used in China. These cooking furnaces release SO2 gas and dust into the atmosphere and cause serious air pollution. Experiments were conducted to investigate the effects of vermiculite, limestone or CaCO3, and combustion temperature and time on desulphurization and dust removal during briquette combustion in small domestic cooking furnaces. Additives used in the coal are vermiculite, CaCO3 and bentonite. Vermiculite is used for its expansion property to improve the contact between CaCO3 and SO2 and to convey O-2 into the interior of briquette; CaCO3 is used as a chemical reactant to react with SO2 to form CaSO4; and bentonite is used to develop briquette strength. Expansion of vermiculite develops loose interior structures, such as pores or cracks, inside the briquette, and thus brings enough oxygen for combustion and sulphation reaction. Effective combustion of the original carbon reduces amounts of dust in the fly ash. X-ray diffraction, optical microscopy, and scanning electron microscopy with energy dispersive X-ray analysis show that S exists in the ash only as anhydrite CaSO4, a product Of SO2 reacting with CaCO3 and O-2. The formation of CaSO4 effectively reduces or eliminates SO2 emission from coal combustion. The major factors controlling S retention are vermiculite, CaCO3 and combustion temperature. The S retention ratio increases with increasing vermiculite amount at 950degreesC. The S retention ratio also increases with increasing Ca/S molar ratio, and the best Ca/S ratio is 2-3 for most combustion. With 12 g of the original coal, 1 to 2 g of vermiculite, a molar Ca/S ratio of 2.55 by adding CaCO3, and some bentonite, a S retention ratio >65% can be readily achieved. The highest S retention ratio of 97.9% is achieved at 950degreesC with addition of 2 g of vermiculite, a Ca/S ratio of 2.55 and bentonite.; Mineralogy; SCI(E); EI; 2; ARTICLE; 6; 1243-1251; 67
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/311418]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Lu, A,Zhao, D,Li, J,et al. Application of vermiculite and limestone to desulphurization and to the removal of dust during briquette combustion[J]. mineralogical magazine,2003.
APA	Lu, A,Zhao, D,Li, J,Wang, C,&Qin, S.(2003).Application of vermiculite and limestone to desulphurization and to the removal of dust during briquette combustion.mineralogical magazine.
MLA	Lu, A,et al."Application of vermiculite and limestone to desulphurization and to the removal of dust during briquette combustion".mineralogical magazine (2003).