固-液搅拌槽的分散性能

在直径为0.478 m的立式搅拌槽中，采用高岭土和水为物料，比较了四斜叶、六直叶涡轮等8种桨的固-液分散性能及搅拌功率(P)、桨组合形式对分散性能的影响规律. 结果表明，8种桨中分散效果最好的是六直叶涡轮桨和四斜叶桨，分散速率最快的是两叶CBY桨；分散速率与P1.08成正比；分散前期，搅拌功率增加，相对分散效果Y随之提高，当Y达到0.999以上，提高搅拌功率对搅拌效果几乎不起作用；采用分散速率较快(两叶CBY桨)与分散效果较好(四斜叶桨)的双桨组合，更适于连续操作过程.

Solid-Liquid Dispersion in a Stirred Tank

The solid-liquid dispersion property by eight types of impeller such as four-pitched-blade turbine (PBT), Rushton turbine (RT), etc, and the influences of stirring power and impeller combinations on dispersion property were studied in a vertical stirred tank with diameter of 0.478 m. Kaolin particles were chosen as the particulate material to be dispersed in the water. The experimental results show that PBT and RT have the optimum dispersion performance, while the 2-blade CBY propeller has the shortest dispersion time. The dispersion rate is in the direct ratio of 1.08 to the stirring power. In the beginning period, the relative dispersion performance Y increases with the stirring power, but the stirring power has little influence on the dispersion performance when the relative dispersion performance Y is more than 0.999. The results also reveal that the combination of a bottom 2-blade CBY and an upper PBT has a clear advantage in continuous operation.