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针对焦炭燃烧过程,提出了一种基于反应位点的焦炭反应动力学模型.焦炭燃烧过程中,反应位点失活、比表面积覆盖以及无机组分的催化作用会导致整体反应速率下降.模型利用表面反应位点数目的变化来表征焦炭燃烧后期反应活性的衰减.研究了不同温度下,焦炭燃烧过程中颗粒温度,焦炭燃尽时间以及其对应的燃烧模式的变化规律.比较了反应位点衰减抑制模型的加入,对焦炭燃尽时间和物性参数变化规律的影响.结果表明:1200、1500和1800K这3种环境温度下焦炭颗粒最终稳定的温度分别为1600、2100和2300K;1200K和1800K下焦炭颗粒燃烧过程分别由化学反应和扩散控制,而1500K下,燃烧模式介于两者之间.抑制模型的加入,延长了焦炭燃尽时间,并且减缓了粒径(Dp)、表观密度(ρp)及比表面积(Sp)的变化速度.“,”A model based on reaction sites was developed to predict the temperature and physical properties changing behavior of pulverized burnout char particle. During char burnout, deactivation of reaction sites, ash coverage of carbon surface area and catalysis of inorganic mineral decreased the global reaction rate. An inhibition model considering the reaction sites number reduction was used to describe the loss of char reactivity. The char temperature history, char burnout time and physical properties changing behavior in different ambient temperatures were investigated using this model. The effect of inhibition model on the whole burnout model was also studied. The results show that the stable char burnout temperature in 1200、1500 and 1800 K ambients are separately 1600、2100 and 2300 K. Model calculations also verify the two burning zones in 1200 K and 1800 K (reaction control and diffusion control). Considering the inhibition model, the char burnout time becomes longer and the changing behaviors of particle diameter, particle apparent density and surface area are all delayed.