The electromagnetic field modeling as a tool in the microwave heating feasibility studies

The electromagnetic field modeling of a loaded microwave applicator can help in choosing the proper conditions to successfully organize feasibility studies, allowing savings of time and money, which are usually wasted during "blindfold" tests. As a matter of fact, when microwave heating of materials is performed, the pronounced nonhomogeneity of the field distribution in multi-mode applicators can produce contradictory experimental results, leading to erroneous conclusions regarding the main variables controlling the process. This is particularly true considering the microwave heat treatment of low thermal conductivity materials. Two different applications in the ceramic field, comparing the results of "blindfold" and modeling-aided experimental conditions, are presented: de-binding of technical ceramics and asbestos inertization and/or vitrification. Thanks to a better knowledge of the electromagnetic field in the applicators, it has been possible to succeed in applications that, at a first glance, did not seem promising at all.