悬浮状态下氯化钠晶体二次成核过程研究

Secondary Nucleation Process of Sodium Chloride Crystal in the Suspended Status

实验利用60 L流化结晶装置,研究了悬浮状态下晶种粒度、流体循环速率以及循环时间对碰撞成核速率特征、规律及晶核粒度分布的影响。发现二次成核过程中,破碎机理占主导作用,碰撞后的晶体碎片具有连续分布;母晶粒度和循环速率不仅影响颗粒的碰撞能,而且对颗粒的悬浮状态及分布状况有明显作用;成核速率随晶种粒度及流体速度的增大而增加,循环时间对粒度较大晶体颗粒的二次成核有明显作用。

The effect of crystal size, circulating rate and circulation time on the collision nucleation rate and crystal size distribution in the suspended status have been experimentally studied for the use of 60 L fluidized crystallization equipment. In collision nucleation process, the fracture mechanism plays a major role, the crystal fracture after collision has distributed continuously. Moth- er crystal size and circulating rate not only effect the collision energy of crystal, but also the suspen- ded status and distribution state. Nucleation rate increased with mother crystal size and stirring intensity. Meanwhile, circulation time has a remarkable effects on the collision nucleation rate of large size crystal.