Agglomeration breakage

Crystal morphology (i.e., both form and shape) affects crystal appearance solid-liquid separations such as filtration and centrifugation product-handling characteristics such as dust formation, agglomeration, breakage, and washing and product properties such as bulk density, dissolution kinetics, catalytic activity, dispersability, and caking. 

Agglomerate porosity can be measured by gas adsorption or mercuiy porosimetiy. However, any breakage or compression of the granules under high pressure during porosimetiy can invahdate the results. 

Alternatively, numerieal methods may be employed to solve the population balanee using diseretization, partieularly in those eases when erystal breakage and agglomeration proeesses oeeur (see below). 

Equation (3.14) is thus eonsistent with the general population balanee (equation 3.8) when B = D = Q i.e. nueleation oeeurs at zero size and both the birth and death terms due to agglomeration and breakage are negleeted, and the feed is erystal-free. 

Crystal agglomeration and disruption 111 Both breakage funetions ean be eheeked for eonsisteney using the relation... 

The population balanee eoneept enables the ealeulation of CSD to be made from basie kinetie data of erystal growth and nueleation and the development of this has been expounded by Randolph and Larson (1988), as summarized in Chapters 2 and 3. Bateh operation is, of eourse, inherently in the unsteady-state so the dynamie form of the equations must be used. For a well-mixed bateh erystallizer in whieh erystal breakage and agglomeration may be negleeted, applieation of the population balanee leads to the partial differential equation (Bransom and Dunning, 1949)... 

If crystal agglomeration and breakage can be neglected and crystal growth is invariant then at steady state the familiar analytic form is... 

The cluster size distribution in the limit of small mass [x < s(f)] depends on the properties of the agglomerates undergoing fragmentation. If infinitesimal particles are formed on a single breakage, that is, b(r) r", then... 

The first-principle method used in the present study will be outlined below. Population balance analysis on a perfectly mixed batch crystallizer with negligible crystal breakage and agglomeration yields the familiar nucleation rate equation used by Misra and White (5)... 

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