氢氧化铝颗粒的附聚动力学研究

以往的氢氧化铝颗粒尺寸对其附聚动力学影响的研究结果不甚相同,本文对此进行了进一步的研究。基于附聚过程的颗粒二元碰撞模型,以粒径ri-1,ri,ri 1的3种颗粒为作用物,按照穷举法,建立了附聚的物理模型。依照附聚模型给出了氢氧化铝颗粒的附聚速率方程,根据差分法求出了附聚的宏观速率,建立了不同粒径颗粒的附聚速率方程组。计算的动力学结果表明:等径颗粒的附聚速率常数要大于不等径颗粒的附聚速率常数;对于等粒径的颗粒,其中粒径最小的颗粒附聚速率常数最大,随着粒径增加,颗粒的附聚速率常数逐渐减少;对于不等径颗粒,其粒径相差越大,附聚的速率常数越小;动力学的计算结果与实验结果能够很好地吻合。

Study on the Agglomeration Kinetics of Gibbsite Particles

A further study on the effect of gibbsite particle size on its agglomeration kinetics is in order,since previous studies tell us different results.Based on a binary collision model of the agglomeration process,an agglomeration model is proposed,where particles of different sizes ri-1,ri and ri 1 are used as reactants and the method of exhaustion is adopted.Equations of the agglomeration rate are derived from the model and the total agglomeration rates are worked out according to the experimental data by a difference method.Equations of agglomeration rates for different particles are established.It is shown that particles of the same size have larger rate constants of agglomeration than the ones of different sizes.For particles of the same size,the particles with the smallest size have the maximum rate constants and the rate constants decrease with particle size.For particles of different sizes,the more diverse the particle sizes,the less the rate constant is.There is a good agreement between calculated kinetics results and experimental results.