Effective atmospheric freeze drying

Reyes, A., Vega, R.V., and Bruna, R.D., Effect of operating conditions in atmospheric freeze drying of carrot particles in a pulsed fluidized bed. Drying TechnoL, 28,1185-1192,2010. 

Fig. 8.11 Identified effective difFusivities of atmospheric freeze drying —14°C, 2ms of carrot, eggplant and apple, with (AIR+ US) and without (AIR) ultrasound application (19.5 kW m , ...

Tab. 8.2 Identified effective diffusivity (De) and mass transfer coefficient (k) of different products during atmospheric freeze drying (—and 2ms ) with ultrasound (US ...

The majority of freeze-drying and spray-freeze-diying methods are batch oriented. In terms of cost-effectiveness continuous processes are generally preferred [4]. It was intended to create a closed, continuous process for the production of monodisperse, spherical lyophilisates for nasal and pulmonary application of biological APIs. Different approaches were tested. Droplets generated by a DSG or 2N were to be frozen in a cold gas atmosphere and sublimation-dried in a counter-current gas flow, in an evacuated lyophiUzation tunnel [5], or by a percolating gas flow on a sieve [6]. 

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