Gas–solid separation fluidized bed is a typical method for coal separation without water utilization. Geldart A particles is also considered as the ideal dense medium to strengthen separation efficiency. Fluidization stability reflects the bed pressure fluctuations and the distribution of bubble and emulsion phases, affecting the separation performance. And the main frequency of pressure fluctuations can directly reflect the degree of pressure fluctuations. Therefore, the detailed fluidization stability is analyzed combined the method of standard deviation of pressure fluctuations, power spectral density, etc., for Geldart A particles. The results showed that maintaining an appropriate gas velocity resulted in an average bed pressure of around 2000 Pa. The main frequency is mainly concentrated around 1–1.5 Hz. Finally, a prediction model of the main frequency of pressure fluctuations is established, and the error can be controlled within ±0.15. The investigation further proved the stable fluidization of Geldart A particles and provides a method for predicting the main frequency of pressure fluctuations in the gas–solid separation fluidized bed.

中文翻译：

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Geldart A 致密介质气固分离流化床的流化稳定性和周期性波动

气固分离流化床是典型的不用水煤分离方法。 Geldart A 颗粒也被认为是增强分离效率的理想致密介质。流化稳定性反映了床压波动以及气泡和乳液相的分布，影响分离性能。而压力波动的主频可以直接反映压力波动的程度。因此，结合压力波动标准差、功率谱密度等方法对Geldart A颗粒进行详细的流化稳定性分析。结果表明，保持适当的气速可使平均床压在2000 Pa左右，主频率主要集中在1~1.5 Hz附近。最后建立了压力波动主频率的预测模型，误差可控制在±0.15以内。研究进一步证明了Geldart A颗粒的稳定流化，并为气固分离流化床压力波动主频率的预测提供了方法。