Granule growth mechanisms

Figure 35. Granule growth mechanisms for population balance modeling. (From Litster and Ennis, 1994.)...

P.A.L. Wauters, R.B. Jakobsen, J.D. Litster, G.M.H. Meesters, B. Scarlett, Liquid distribution as a means to describing the granule growth mechanism, Powder Technol. 123 (2002) 166-177. 

Van den Dries K, Vromans H. 2002. Relationship between inhomogeneity phenomena and granule growth mechanisms in a high-shear mixer. Int. J. Pharm. 247 167-177. 

Fig. 3 Granule growth mechanisms (A) agglomerate formation by nucleation of particles (B) agglomerate growth by coalescence (C) layering of a binder-coated granule and (D) layering of a partially filled binder droplet. (From Ref John Wiley and Sons, Inc.)...

Van den Dries K, Vromans H. Relationship between inhomogeneity phenomenon and granule growth mechanisms in a high-shear mixer. Int J Pharm 2002 247 167-177. Paris L, Stamm A. Optimal massing liquid volume determination by energy consumption measurement study of the influence of some physical properties of solvent and products used. Drug Dev Ind Pharm 1985 ll(2,3) 361-386. 

In general, analytical solutions are only available for specific initial or inlet size distributions. However, for batch granulation where the only growth mechanism is coalescence, at long times the size distribution may become self-preserving. The size distribution is selfpreserving if the normahzed size distributions

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Nucleation and growth mechanisms are described in detail in texts on precipitation (Sohnel and Garside, 1992), and crystallization (Mullin, 2001 Mersmann, 2001 and Myerson, 2001). Granulation is considered in Sherrington and Oliver (1981), Stanley-Wood (1990) and Pietsch (1991) whilst comminution is dealt with in Prior etal. (1990). 

Figure 12. Mechanisms of granule growth, adapted from Tardos et al. (1991).

Waldie, B., Growth Mechanism and the Dependence of Granule Size on Drop Size in Fluidized-Bed Granulation, Chem. Eng. Sci., 46 2781-2785 (1991)... 

Smith, P.G. and Nienow, A.W., Particle growth mechanisms in fluidised bed granulation - part I. The effect of process variables, Chem. Eng. Sci., 38 (1983) 1223-1231. 

Only Smith and Nienow (1983a) have reported a systematic investigation of the effects of gas velocity on granule size and on particle growth mechanisms. These authors used model materials (non-porous... 

Smith, PG. and Nienow, A.W., Growth mechanisms in fluidised bed granulation. Proceedings of an International Symposium on Particle Technology, I.Chem.E. Symp. Ser. No. 63 (1981) D2/K/1. 

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