抄録
Computer simulation of agglomeration of mono-sized circles on a two-dimensional plane was undertaken by a random addition model to investigate the mechanism of agglomeration of dispersed particles in a liquid suspension. Under centripetal force, a new circle approached a circle placed on the origin from a random direction. Two types of agglomerations, i.e. closely and loosely packed agglomerations, were simulated by using different process of adhesion of the circles. For the closely packed agglomeration, the internal packing structure was independent of the probability coefficient of adhesion (Pr), but the agglomeration rate was Pr dependent. The packing structure and the agglomeration rate of loosely packed agglomeration were determined by the probability coefficient of adhesion (Pa). Heterogeneous agglomeration was also simulated by defining two types of circles, e.g. A and B, with different adhesion properties, which determined the internal composition and the structure of the agglomerate. By introducing the probability coefficient of collision (Pc), a practical agglomeration process in a batch system in which the residual numbers of particles decrease as the agglomeration proceeds could be described. A layering agglomeration could be visualized by defining Pc as n1/n10. Population balance for this agglomeration led the rate equation expressed by equation (3) in the text. The agglomeration rates of loosely and closely packed agglomerations were determined in terms of Pa and Pr, respectively. The rate of heterogeneous agglomeration was less dependent upon Pa than the others. The internal packing structure of agglomerates strongly depended on Pa ; when Pa increased, the porosity of the agglomerate increased and the average coordination number decreased. The porosity could be correlated qualitatively with the coordination number.
