“3D layered thermography” method to map the temperature distribution of a free flowing bulk in case of microwave drying

Microwave drying is getting more and more popular even in the highly regulated pharmaceutical field. In spite of its uniqueness there is a rightful resistance because of the non-homogeneous electric field that cause non-homogeneous temperature distribution. The dielectric and thermal properties of any complex workload are rarely known, and moreover, they change during a drying process, which makes experimental tests essential to complete any mathematical modelling. To get a 3D overview of a free-flowing bulk the workload was divided with Teflon layers to form cross-sectional surfaces. After dissipation of microwave energy, IR thermocartograms were taken and temperature distribution was evaluated even quantitatively. The “3D layered thermography” method offers reliable and workload-specific information via simple executable technique for the optimization of a microwave processes.