Fluidized bed granulation growth models

The volume of binder adhering fo each core parficle is equal fo the difference in volume befween spheres of diamefer d and d respectively, thus 

The mass m of a single core particle of density ps is given by 

if the volume of binder associated with each particle is 

Equation 5.16 can be solved for a, the layer thickness, from a knowledge of the total mass, density and mean diameter of the initial (core) 

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