带内置水平管的大颗粒振动流化床流体力学研究

Experimental research of bed pressure drop in large particles vibrated fluidized bed with internal horizontal tubes

以大颗粒MAP(磷酸一铵)为试验物料对带内置水平管的大颗粒振动流化床流体力学进行了试验研究,结果表明,振动的引入对床层临界压降有明显的降低作用;同样床层条件下振动频率越大床层临界压降越低,振幅的改变对床层压降影响不大;低气速下振动使床层孔隙率降低而导致压降高于普通流化床;在带内置水平管的大颗粒振动流化床中,振动对大粒径颗粒的影响小于小粒径颗粒;由试验拟合出经验公式,与试验数据吻合良好。

The vibrated fluidized bed with internal horizontal tubes was established, and the bed pressure drop in large particles vibrated fluidized bed with internal heating tubes was studied experimentally with large ammonium diaeid phosphate particles as experimental material. The results showed that implication of vibrations is visible to decrease the critical pressure drop of the bed. Under same bed condi- tions, the larger the vibration frequency is, the lower the critical pressure drop will be; the effect of vibration amplitude on critical pressure drop is little. At low gas velocity, the vibration could reduce the bed porosity, and then induce higher pressure drop in vibrated fluidized bed than common fluidized bed. In the vibrated fluidized bed with internal horizontal tubes, the vibrations have more effects on small particles than large particles. An empirical formula was derived from the experiments, and showed good agreement with the experiment data.