Abstract

In this study, the drying of dielectric materials by a continuous microwave belt drier has been investigated experimentally. Most importantly, it focuses on the investigation of drying phenomena under microwave environment. In this analysis, the effect of the irradiation time, sample sizes, and microwave power level (number of magnetrons (800W∕1 magnetron)) on overall drying kinetics and mechanical properties are studied. The dielectric materials studied are classified into two types including ceramics (microwave demolding of tableware product) and natural rubber. 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, and high energy efficiency compared with other process, and it offers improvements in product quality. The results presented here provide a basis for fundamental understanding of microwave-heating of various kinds of dieletric materials. Further quantitative validation of experimental data could be very useful, especially in providing information for processing high performance microwave drying for developing the ceramics and rubber industries in Thailand.

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