摘要
准格尔电厂粉煤灰中的A l2O3含量高达52.72%,这在世界上十分少见,为详细了解这一特殊粉煤灰的成因并加以高附加值利用,采用ICP-AES,XRD和FESEM-EDX等方法详细研究了该电厂炉前煤的煤岩、煤质、煤中矿物组成和灰成分特征,同时测定了粉煤灰的化学成分.结果表明,准格尔电厂煤中矿物以高岭石和勃姆石为主,分别占煤中矿物总量的71.1%和21.1%.粉煤灰中高A l2O3含量来源于煤中丰富的高岭石和勃姆石矿物在电厂高温下的转化和分解产物;石英仅占煤中矿物组分的1.9%,也相应地提高了粉煤灰中的A l2O3/SiO2质量比,使得这一比值达到1.50,是常见粉煤灰的3倍左右.煤中其它矿物含量较少,使得粉煤灰中其它氧化物含量相应降低,这为高铝粉煤灰的高附加值利用奠定了良好基础.
The abnormally high-alumina fly ashes, with as high as 52. 72% of Al2O3, are being produced in the Jungar Power Plant of Inner Mongolia. In order to understand and utilize this high-alumina fly ash, petrology and mineralogy of the feed coal as well as the chemistry of the fly ash were studied using optical microscopy, inductively coupled plasma atom emission spectrometry （ ICP-AES）, X - ray diffraction （ XRD ） and field emission scanning electron microscopy linked with energy-dispersive X-ray spectrometry （FESEM -EDX）. The results show that the predominant minerals in the feed coals are kaolinite and boehmite, averaged 71.1% and 21.1% among the total crystal minerals, respectively. The high level of Al2O3 in the fly ash is yielded during the transformation and decomposition of kaolinite and boehmite in the feed coal at a high temperature, commonly between 950 - 1 200 ℃, Very low level （1.9 % ） of quartz in all minerals of the coal has correspondingly elevated the Al2O3： SiO2 ratio of the fly ash up to 1.50, which is three times of common fly ash in China. Other minerals have a very low level in the feed coal, leading to very low levels of other oxides （impurity） in the fly ash. These results lay a foundation for value-added utilization of the high-alumina fly ash.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2007年第4期411-415,共5页
Journal of China Coal Society
基金
教育部高等学校科技创新工程重大项目培育资金资助项目(705022)
教育部新世纪优秀人才资助项目(教技司[2005]2号)
关键词
炉前煤
矿物组成
高铝粉煤灰
莫来石
feed coal
mineral composition
high-alumina fly ash
mullite
