A Measurement System for Lyophilization Process Monitoring

Lyophilization processes are widely employed in the industrial field to preserve several kinds of substances, such as foods and drugs. In some cases, e.g. during the process optimization, the real-time measurement of mass and temperature is important to monitor drying rate and to prevent product damages because of unsuitable temperatures. In these cases sensors and measurement instruments have to be installed inside the vacuum chamber of the freeze dryer, where temperature and pressure can reach -60degC and 1 Pa respectively. This paper deals with the problems related to the measurement of mass and temperature inside freeze dryers and describes a measurement system that has been specifically designed to monitor lyophilization processes.