二元气-固流化系统临界流化速度的研究

Study on Critical Fluidizing Velocity in a Binary Mixture Liquid-Solid Fluidization System

在直径为4cm的有机玻璃流化床中,对由不同尺寸和质量分数的铁矿石和煤颗粒组成的二元气-固流态化系统进行了流化特征的实验研究,得到了该系统的流化特性曲线,给出了临界流化速度和二元系统混合颗粒平均直径之间的关系,用该关系式对临界流化速度进行了预测,并且将预测值和实验值进行了比较。结果表明,当煤颗粒的质量分数为10%时,临界流化速度umf与颗粒直径的平方dm2的关系为umf=0.13dm2+1.2;当煤颗粒的质量分数为20%时,两者的关系变为umf=0.12dm2+1.2,预测值与实验值误差在10%以内。

A binary mixture fluidization system composed of iron ore and coal particles of different size and component was experimentally studied in an organic vitreous fluidized bed of 4 cm inner diameter. The fluidization curves of the binary mixture fluidization system was obtained and the relation of the minimum fluidizing velocity and binary mixture average particle diameter was given. The critical fluidization velocity was predicted with this relationship and the prediction value and the experimental value were compared. Minimum fluidizing velocity had a relation of unf=0.13dm^2＋1.2 when 10 % （mass fraction） coal particles was mixed, and u,,=0.12dm^2＋ 1.2 was observed for that of 20 % coal particles mixed, and the error of prediction value and experimental value was less than 10 %.