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chemical engineering research and design 8 6 ( 2 0 0 8 ) 1369–1381

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Chemical Engineering Research and Design journal homepage: www.elsevier.com/locate/cherd

Deagglomeration processes in high-shear devices
Jerzy Bałdyga a,∗ , Łukasz Makowski a , Wojciech Orciuch a , Caroline Sauter b , Heike P. Schuchmann b a b

´ Faculty of Chemical and Process Engineering, Warsaw University of Technology, ul. Warynskiego 1, 00-645 Warsaw, Poland Institute of Food Process Engineering, University of Karlsruhe (TH), Germany

a b s t r a c t
Methods of modeling, results of simulations and comparisons of model predictions with experimental data are presented for formulation of nano-suspensions by breaking up micron size nano-particle clusters in high-shear devices. An in-line rotor–stator, a high-pressure nozzle disintegrator and an ultrasonic device are considered; in particular, performance of the ultrasonic device is compared with results obtained previously for an in-line rotor–stator [J. Bałdyga, W. Orciuch, Ł. Makowski, K. Malik, G. Ozcan-Taskin, W. Eagels, and G. Padron, 2008. Dispersion of nanoparticle clusters in a rotor–stator mixer. Ind. Eng. Chem. Res. 47, 3652–3663] and the high-pressure nozzle [J. Bałdyga, W. Orciuch, Ł. Makowski, M. Malski-Brodzicki, and K. Malik, 2007. Break up of nano-particle cluster in high-shear devices. Chem. Eng. Process. 46 (9), 851–861]. A recently developed breakage model has been applied in our previous work [J. Bałdyga, W. Orciuch, Ł. Makowski, K. Malik, G. Ozcan-Taskin, W. Eagels, and G. Padron, 2008. Dispersion of nanoparticle clusters in a rotor–stator mixer. Ind. Eng. Chem. Res. 47, 3652–3663] to interpret erosive dispersion of agglomerates in the rotor–stator mixer. This paper deals with devices that generate much higher hydrodynamic stresses than that generated in the rotor–stator mixer. To interpret such high shear processes a model of breakage based on rapture mechanism is