Experimental study of a single char particle combustion characteristics in a fluidized bed under O-2/H2O condition
Experimental study of a single char particle combustion characteristics in a fluidized bed under O-2/H2O condition
复制标题
O-2/H2O条件下流化床中单个焦粒燃烧特性的实验研究
DOI：
10.1016/j.cej.2019.122942
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发表时间：
2020
影响因子：
15.1
通讯作者：
Zhao Changsui
中科院分区：
文献类型：
--
作者：
Li Lin;Duan Lunbo;Yang Zhihao;Tong Shuai;Anthony Edward John;Zhao Changsui
Oxy-steam combustion is a potential new route for oxy-fuel combustion with carbon capture from coal-fired power plants. In the present work, the combustion behavior of single char particles were investigated in a transparent fluidized bed combustor under different operating conditions (i.e., gas atmosphere, oxygen concentration, coal rank, location, fluidization number, particle size, and bed temperature). Both pre-calibrated two-color pryrometry and a flexible thermocouple were used to measure the char particle temperature in the combustion tests. Results indicated that the pore structure of the char generated in H2O atmosphere was better than that generated in CO2and N2atmospheres. As expected, with increase of oxygen concentration, the burnout time (tb) decreased, and the particle temperature (Tp) increased. The sequence of burnout times for different rank coal char particles was: anthracite > bituminous coal > lignite. Interestingly, comparing O2/CO2and O2/N2combustion, a shortertband a lowerTpof char could be achieved simultaneously in O2/H2O combustion, regardless of location and oxygen concentration. Furthermore, the increase of fluidization number strengthened the mass and heat transfer between the char and the environment, thereby reducing thetbandTpof char. With increasing of particle size, theTpslightly decreased, thetbincreased markedly, and the gasification reactions became more and more significant. As the bed temperature increased, the gasification rate increased exponentially, and the mass transfer coefficient increased gradually.
