流化床气化炉半焦细粉水蒸气再气化特性及动力学研究
Steam re-gasification properties and kinetics of coal char fines derived from fluidized bed gasifier
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摘要: 利用热天平考察了流化床气化炉半焦细粉的水蒸气再气化特性及其动力学,并与相应的自制半焦及脱灰半焦细粉进行了比较分析.结果表明,半焦细粉的再气化反应性随着温度的升高而增加.与自制热解半焦相比,半焦细粉的反应性较高,这主要取决于比表面积的影响,而不同细粉的气化反应性差异还与其石墨化程度和灰含量有关.在此基础上,利用缩核模型对半焦细粉的再气化行为进行了模型拟合并得到了动力学参数,从而为细粉的再气化提供了一定的理论指导.Abstract: The steam gasification behavior and kinetics of coal char fines derived from fluidized bed gasifier were investigated by TGS-2 thermogravimetric analyzer. Their physical and chemical properties were also compared with the corresponding coal chars and demineralized char fines. The results show that the gasification reactivity of char fines increase with increasing temperature. Compared with the coal char from pyrolysis, the char fine has a larger surface area and leads to a higher gasification reactivity. The reactivity of different coal char fines are also affected by their carbon crystalline structure and ash content. Based on this, the gasification reactions are described by the shrinking core model and the kinetic parameters are obtained, so as to provide some theoretical guides for the gasification of coal char fines.