Abstract The multi-regime CFB riser equipped with a bottom diameter-enlarged section has been demonstrated to be efficient in increasing the overall solids holdup and enhancing the gas-solid contact previously. In this work, the swirling gas nozzles have been incorporated into the diameter-enlarged section to further improve the gas-solid mixing behavior, and the effect of the nozzle directions on the gas-solid flow patterns has been systematically studied. The results indicated that, with the sacrifice of small amount of solids circulation rate, the solids concentration in the diameter-enlarged section using swirling gas nozzles was further increased, and the height of the dense phase was elevated, providing more available catalyst for gas-solid contact reactions. In addition, the gas phase injected through the swirling nozzles exhibited a rotational rising flow behavior and effectively penetrated into the solid phase near the wall region, consequently intensifying the gas-solid fluctuation and contact.

中文翻译：

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旋流喷嘴对新型多段立管内气固流型的影响

摘要 配备底部扩径段的多段 CFB 立管已被证明在增加整体固含量和增强气固接触方面是有效的。在这项工作中，旋流气体喷嘴已被纳入扩径段，以进一步改善气固混合行为，并系统地研究了喷嘴方向对气固流动模式的影响。结果表明，在牺牲少量固体循环速率的情况下，使用旋流气体喷嘴的扩径段固体浓度进一步增加，致密相高度升高，为气体提供了更多的可用催化剂。固体接触反应。此外，