The microwave processing of wood using a continuous microwave belt drier

In this study, the drying of wood by microwave energy using a continuous microwave belt drier was compared to that by conventional method. By using a continuous microwave belt drier, the microwave power was generated by means of 14 compressed air-cooled magnetrons of 800 W each that gives a maximum of 11.2 kW. The power setting could be adjusted individually in 800 W steps. Most importantly, this work focuses on the investigation of drying phenomena under microwave environment. In this analysis, the effects of the irradiation time and microwave power level on overall drying kinetics and mechanical properties were studied. The results showed that using the continuous microwave applicators technique has several advantages over the conventional method such as shorter processing times, volumetric dissipation of energy throughout a product, high energy efficiency as well as improvements in product quality. The results presented here provide a fundamental understanding of microwave-heating of various kinds of dielectric materials.

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