Granulation processes, modeling population balance

Han (H3) and Han and Wilenitz (H4) have also presented steady-state models of fertilizer granulators based on population balance on the granules in the process loop operating in the snowballing mode. From the viewpoint of process control some interesting interrelationships between various recycle ratios, crusher speed, crusher product size, and the granule growth rate have been established. 

The following sections develop in detail some of the important aspects of granulation process modeling, through the use of population balances and alternative approaches. 

Extent of Noninertial Growth Growth by coalescence in granulation processes may be modeled by the population balance. (See the... 

The authors would like to acknowledge that the section dealing with population balance modeling of granulation processes is an abbreviated version of material prepared by Dr. J. D. Litster, University of Queensland, for a joint short course given by Dr. B. J. Ennis and Dr. J. D. Litster. 

Immanuel, C. D. Doyle, F. J. 2005 Solution technique for a multi-dimensional population balance model describing granulation processes. Powder Technology 156,213-225. 

Growth by coalescence in granulation processes may be modeled by population balances (Chapter 21). It is necessary to determine both the mechanism and the kernel which describe growth. For fine powders within the noninertial regime of growth, all collisions result in successful coalescence provided binder is present. Coalescence occurs via a random, size independent kernel which is only a function of liquid loading y, as well as mixing, or... 

Population balance modeling provides an important basis for optimal design and operations for both batch and continuous granulation processes. 

There is a growing interest in what is, somewhat misleadingly, called multidimensional population balance models. One example of a 2D PB model is the description of a granulation process where not only the particle size distribution with time, but also the fractional binder content is predicted by the model. The binder (liquid) content of the granules governs the agglomeration process. 

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