Dehydration by a Desiccant
Dehydration by a Desiccant
This Demonstration estimates the amount of desiccant needed to lower the water activity, , of a food or pharmaceutical powder. The powder's moisture sorption isotherm is described by a three-parameter generic BET/GAB model, and that of the desiccant by a two-parameter power model. These equations' parameters are determined by fitting experimental sorption data. The Demonstration solves a mass balance equation, based on the powder's and desiccant's moisture sorption isotherms, the powder's initial wet mass, initial , and the desired final . It is assumed that the system is closed, the temperature is constant, the desiccant is added bone dry, and any moisture in the free space is negligible.
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