DYNAMICS AND STABILITY OF CONTINUOUS MSMPR AGGLOMERATIVE PRECIPITATION - NUMERICAL-ANALYSIS OF THE DUAL PARTICLE COORDINATE MODEL

This article presents a bi-variant dynamic model of continuous mixed-s uspension, mixed-product-removal (MSMPR) precipitation with agglomerat ion (aggregation and disruption) using the dual particle coordinate (a gglomerate size and primary crystal number) population balance approac h. Several finite difference methods were first examined for numerical solution of simplified model equations. The implicit forward time cen tral space (FTCS j + 1) was selected as the best for prediction of dyn amic particle size distribution (PSD) and then applied to the agglomer ative case. For specific values of aggregation and disruption coeffici ents, K-a and K-d, bimodal distributions are observed and the system c an also exhibit unstable dynamics. It is also predicted, however, that a supersaturation dependence of aggregation efficiency together with crystal disruption can stabilize the system transient response. (C) 19 98 Elsevier Science Ltd. Al rights reserved.