The influence of included minerals on the intrinsic reactivity of chars prepared under N2 and CO2 environment
Oxy-fuel technology could be successfully used to retrofit existing coal-fired power plants or alternatively be used to design and build new coalfired power plants with almost zero emissions.Char reactivity under oxy-fuel conditions will have a significant impact on the coal burnout. In this paper,two fractions,representing organic-rich particles and organic particles with included minerals,were separated from each of three Chinese coals of different rank.They were then devolatilized at 1450°C in a drop tube furnace (DTF) under N2 and CO2 environment,respectively.The chars were subjected to nitrogen adsorption study,thermogravimetric analysis and XRD analysis. It was found that char reactivity of all three pairs of chars were increased under CO2 environment as compared with that under N2 environment,but with differing trend.For the organic-rich samples the reactivity difference is increased with decreasing rank.On the contrary,for the samples of organic particles with included minerals,the reactivity difference is decreased with decreasing rank. Mechanism analysis showed that they are resulted not from gasification,but from a combination of changes in surface area and in the ordemess of carbon structure in the chars,both of which,in turn,are resulted from the higher heat capacity of CO2 and the interaction between metastable liquid phase and the included minerals..
mineral matter char structure reactivity oxy-fuel combustion
Hong Zhang Huan Li Jiabao Chen Bo Zhao Guangzhou Hu
School of Chemical Engineering,China University of Mining & Technology,Xuzhou,Jiangsu 221116,P.R.Chi School of Chemical Engineering,China University of Mining & echnology,Xuzhou,Jiangsu 221116,P.R.Chin
国际会议
The 7th International Symposium on Coal Combustion(第七届国际煤燃烧学术会议)
哈尔滨
英文
795-798
2011-07-19（万方平台首次上网日期，不代表论文的发表时间）