(55b) Model-Based Scale-up of Impact Milling

Glassmeyer, S. R. - Presenter, Procter & Gamble
Pinto, M. A. - Presenter, Process Systems Enterprise
Bermingham, S. K. - Presenter, Process Systems Enterprise

The Vogel
& Peukert model uses separate material properties and mill parameters
determined from bench top experiments to predict the particle size distribution
of the output of impact mills. This turns mill modeling into a tool that can be
used every day at P&G. This talk covers our implementation of this model
and use within the gSOLIDS environment (Process Systems Enterprise, UK). 
We determined the material properties for an absorbent gelling material used in
diapers from sieving and single impact milling experiments.  We
successfully deployed the population balance model of Vogel and Peukert that
predicts the output of our bench top pin mill in gSOLIDS.  The gSOLIDS
tool allowed us to perform parameter estimation of this highly nonlinear model
which gave us distinct material and mill properties.  We then made
successful model predictions of mill scale-up using these same parameters. This
method could potentially save millions annually in experimental costs as we can
generalize this method to any powder that is broken in an impact mill.  
We have thus developed a model-based work process for impact mill scale-up that
uses gSOLIDS at its core.


L. Vogel, W.
Peukert (2005) From single impact behaviour to modelling of impact mills. Chemical
Engineering Science
60, 5164-5176.