Abstract The generation of fines by attrition in fluidized bed reactors can cause problems. Thus, the objective of this study was to examine the amount of fines generated in the cyclone not only by attrition, but also by detachment of fine attached to surface according to time. Using a circulating fluidized bed (0.076 m ID × 3.7 m height), variables including cyclone inlet velocity (20.6–30.9 m/s), solid loading ratio (0.5–1 kg-solid/kg-air), and elapsed time (0.5–13 h) were investigated. The fine generation ratio was analyzed by dividing it into two components: the surface particle detachment ratio and the attrition ratio. The surface particle detachment ratio decreased rapidly with increasing cyclone inlet velocity and solid loading ratio. The attrition ratio was positively affected by the cyclone inlet velocity but negatively affected by the solid loading ratio, as found in previous studies. As the surface particle detachment ratio decreased with elapsed time, its contribution to the amount of fine particles generated decreased over time (73%–91% at 0.5 h and 41% at 5 h). The mass fraction produced by surface particle detachment was approximately 9% for the iron ore and 0.01% for catalyst particles.

中文翻译：

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气固循环流化床旋风分离器中铁矿石的精细生成率

摘要 流化床反应器中因磨损而产生的细粉会引起问题。因此，本研究的目的是检查旋风分离器中产生的细粉量，不仅是由于磨损，而且是随着时间的推移附着在表面的细粉脱落。使用循环流化床（0.076 m ID × 3.7 m 高度），变量包括旋风入口速度（20.6-30.9 m/s）、固体负载比（0.5-1 kg-固体/kg-空气）和经过时间（0.5 –13 h) 进行了调查。通过将其分为两个部分来分析细粉生成率：表面颗粒脱离率和磨损率。随着旋流器入口速度和固体负载率的增加，表面颗粒脱离率迅速下降。磨耗率受到旋风分离器入口速度的积极影响，但受到固体负载率的负面影响，如先前研究中发现的那样。随着表面颗粒脱离率随着时间的推移而降低，其对细颗粒产生量的贡献随时间降低（0.5 小时为 73%–91%，5 小时为 41%）。铁矿石表面颗粒脱离产生的质量分数约为 9%，催化剂颗粒约为 0.01%。