For the scaling-up achieved by the use of the method of wet microwave granulation based on calculations, there is a need for an exact mathematical description for the relationship between the dose of radiation and the resultant effect. By assessing the physical, physical-chemical, and chemical factors, we may conclude that, by the gross kinetic evaluation of the change in the enthalpy and the loss of humidity, there is a possible solution for the mathematical description of the single-step, single-pot granulation from the practical aspect of finding ways to scale-up. This paper overviews the experiments performed in a laboratory-size microwave vacuum granulator in testing two different granules with respect to composition and permittivity and presents the evaluation of the experimental data.