Abstract
As any kind of dryer has its own drying speed, freeze-dryer also has a drying speed as capacity in addition to total shelf surface and ice condensation load to be designed and validated. The drying speed, i.e. sublimation speed and desorption speed mainly depends on the conductance of pipe between drying chamber and ice condenser and the ice condensation speed in addition to heat transfer from shelves to product. Such drying speeds of freeze-dryers should be validated as time-based capacity with full load of water at a required control pressure for the purpose of checking max. allowable set values for operation parameter, challenge tests, reduction in cycle time and future improvement in design and drying performance.
