Microwave-Assisted Drying: A Review of the State-of-the-Art

Offering advantages of energy-saving rapid drying rates, short processing times, deep penetration of the microwave energy, instantaneous and precise electronic control, and clean heating processes, microwave-assisted drying (MWD) has become a popular method that is currently used for many materials and processes. This article presents a systematic and comprehensive review of experimental and theoretical studies regarding the kinetic mechanisms of MWD. Factors affecting, methods for measuring, and applications of the dielectric property are discussed. From the experimental perspective, laboratory- and commercial-scale MWD systems are elaborated, including the equipment used and the stability, safety, and regulation of MWD systems. Theoretical investigations of thermal and nonthermal equilibrium models and moving-load computational models are discussed. Finally, some future trends in the research and development of MWD systems are suggested.