Wet agglomeration of powders: from physics toward process optimization

A general method to optimize a wet powder agglomeration process for achievi ng desired properties of granulated products is suggested. The different st ates of a wet powder are characterized by a cohesion function, i.e. the evo lution of the torque of the stirred system as a function of the moisture co ntent. Two different types of agglomeration behaviours are shown: Stepwise Growing Behaviour (SGB) and Continuous Growing Behaviour (CGB). The influen ce of various parameters such as the particle-size distribution and the wet tability of the solid surface on the cohesion function are highlighted. Suc h functions are shown to be very helpful to define the granulation process and the properties of the granulated products, revealing a promising method ology. (C) 2001 Elsevier Science B.V. All rights reserved.