Abstract: A method to monitor a secondary drying phase of a freeze-drying process comprises initial steps in which is provided to perform pressure rise tests at different time and to calculate a respective value of experimental desorption rate of product (steps 1 to 3). Subsequently, the method provides to estimate initial conditions and kinetic constants of a kinetic model of the process (step 4) and to calculate at time t=t2 a respective residual moisture content and a respective desorption rate (step 5). The method can be performed in a freeze-dryer apparatus which includes a drying chamber that contains a product to be dried and can be isolated to perform pressure rise tests.

Abstract: A freeze-drying process includes a primary drying phase. Within this phase, a test is performed for causing a variation of partial pressure of solvent inside a drying chamber. At the beginning of the test, a product sublimation flux, a total pressure and a partial pressure of the solvent in the drying chamber are measured. A product temperature is estimated at the interface of sublimation at the beginning of the test. The solvent vapor pressure at the interface of sublimation is calculated as is a resistance of a dried layer of the product to the vapor flow of the solvent. Next, a thickness of a frozen layer of the product is calculated and a coefficient of heat transfer between heating surface and product is also calculated. An initial temperature profile of the frozen product is then calculated as is a total pressure in the drying chamber. A value of the product temperature at the interface of sublimation at the beginning of test is determined and a time constant of the freeze-drying process is calculated.

Abstract: An apparatus for moving containers into or from a chamber provided with at least a supporting surface for the containers, comprises a pushing element for engaging the containers and a driving arrangement for moving the pushing element through the chamber along a sliding direction, the driving arrangement comprising, a modular rod assembly for supporting the pushing element and including a set of rod elements which can be mutually and removably associated, an assembling arrangement for connecting or disconnecting the rod elements to or from the modular rod assembly so as to change a length thereof and to move the pushing element.

Abstract: A method for monitoring and/or controlling a freeze drying process is characterized by the use of an estimator algorithm. A product to be dried is arranged in at least one container on a temperature-controlled shelf in the drying chamber of a freeze dryer apparatus. During a primary drying phase, the drying chamber is isolated by closing an isolating valve. Pressure values inside the drying chamber are measured and collected for a defined pressure collecting time and a temperature of the temperature-controlled shelf. A product temperature for the product is calculated together with a plurality of process/product related parameters. A new shelf temperature is calculated with a sequence of shelf temperatures up to the end of the primary drying phase that maximizes a sublimation rate of the product in order to maintain the product temperature below a maximum allowable product temperature.

Abstract: A method to monitor a secondary drying phase of a freeze-drying process comprises initial steps in which is provided to perform pressure rise tests at different time and to calculate a respective value of experimental desorption rate of product (steps 1 to 3). Subsequently, the method provides to estimate initial conditions and kinetic constants of a kinetic model of the process (step 4) and to calculate at time t=t2 a respective residual moisture content and a respective desorption rate (step 5). The method can be performed in a freeze-dryer apparatus which includes a drying chamber that contains a product to be dried and can be isolated to perform pressure rise tests.

Abstract: An apparatus for moving containers into or from a chamber provided with at least a supporting surface for the containers, comprises a pushing element for engaging the containers and a driving arrangement for moving the pushing element through the chamber along a sliding direction, the driving arrangement comprising, a modular rod assembly for supporting the pushing element and including a set of rod elements which can be mutually and removably associated, an assembling arrangement for connecting or disconnecting the rod elements to or from the modular rod assembly so as to change a length thereof and to move the pushing element.