Prediction of agglomerate size for ultrafine particles in acoustic spouted fluidized-bed with draft tube

doi:10.11949/j.issn.0438-1157.20161792

Abstract

Abstract:

The fluidization property of ultrafine particles is closely related to their agglomerate size. Through the analysis of the formation process of ultrafine powder agglomerates in an acoustic spouted fluidized-bed with a draft tube, it is proposed that the shearing action of high speed jet and collision between agglomerates were the dominating factors to influence agglomerate size. Based on the force balance analysis acting on the agglomerates during the jet shearing process and collision between agglomerates, a model to predict agglomerate size distribution in an acoustic spouted fluidized-bed with a draft tube was established. The average size of agglomerates and their size distribution of TiO₂ ultrafine powder at different jet velocities in the bed were predicted by the model successfully.

Key words: nanoparticles, acoustic spouted fluidized-bed with draft tube, shearing action of high speed jet, collision between agglomerates, particle size distribution, prediction model

摘要：

超细粉的流化性能与聚团尺寸密切相关。通过分析超细粉聚团在声场导向管喷流床中的形成过程，提出了高速射流的剪切作用和聚团间的碰撞作用是决定聚团尺寸的主要原因。在此基础上，结合聚团在射流剪切过程和聚团间碰撞过程中的力平衡分析，建立了声场导向管喷流床中聚团尺寸分布的预测模型；并运用这一模型成功预测了不同射流气速下，超细TiO₂颗粒在声场导向管喷流床中的聚团平均直径和聚团尺寸分布。

关键词: 纳米粒子, 声场导向管喷流床, 射流剪切作用, 聚团间碰撞作用, 粒度分布, 预测模型

CLC Number:

TQ021

GAO Kaige, LEI Yuzhuang, LI Hainian, ZHOU Yong. Prediction of agglomerate size for ultrafine particles in acoustic spouted fluidized-bed with draft tube[J]. CIESC Journal, 2017, 68(6): 2290-2297.

高凯歌, 雷玉庄, 李海念, 周勇. 超细粉在声场导向管喷流床中的聚团尺寸预测模型[J]. 化工学报, 2017, 68(6): 2290-2297.

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