A RT ln

and for stoichiometric solutions equals: Aß = RTv ln S + RTva

crystallizer is often assumed to be constant in eqns [12-19], However, by making V and the feed streams time-dependent, dynamic effects can be taken into account, and thus also batch processes. The mass balance is given by:

d^ ^v,feed(£feedPfeed,liquid # (1 £feed)Pcrystal)

Given the relatively low supersaturations, a, that often lie between 0.001 and 0.01 with more easily soluble substances, eqn [8] simplifies into:

v,vapourA^ vapour

The component balances are given by:

dMi ~dt

£feed pfeed,liquid ^^feed,liquid,i

# (1 ^feed)Pcrystal^feed,crystal,i/' ^v,prod(£pliquidWliquid,i # (1 ^)pcrystal^crystal,i)

In practice the supersaturation is often indicated by eqn [5].

For flash cooling or evaporation two terms contribute to the driving force (AT and Ac).

For precipitation, no simplifications are allowed, owing to the high supersaturation values (o> 1), and either eqn [8] or eqn [10] is used. For antisolvent precipitation the value of c depends on the actual concentration of the solute in the original solvent and, like c*, on the degree of dilution by the antisolvent.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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