Process Control Using Advanced Particle Analyzing Systems: Applications from Crystallization to Fermentation Processes

摘要

An advanced particle analyzing system (APAS) was applied to track information on size, shape, and number of particles in suspension. The measurement principle is based on laser reflection. In comparison to conventional laser reflection methods like focused beam reflectance measurement which determines chord/arc lengths, APAS sensors allow to measure exposed particle surface areas (EPSA). Furthermore, APAS is capable to collect information on the particle shape by evaluation of the reflection raw signals. The technique was tested for two different application fields to monitor crystallization and fermentation processes in case studies with L-glutamic acid as well as with cancer cells and Escherichia coli bacteria. It could be demonstrated that improvements in design and technology, coupled with the use of new software, permit to track changes of particle shape, size, and density as well as to analyze features such as cell vitality by the obscuration factor, cell proliferation, and growth effects by the distance of particles. The case studies proved that the innovations of the APAS, i.e., EPSA and particle shape, offer specific enhancement, enabling users to understand, monitor, and optimize products and processes more effectively.