Microwave and Radio-Frequency Technologies in Agriculture

15 Microwave Drying

Many products must be dried before they can be stored or used. For example, drying of animal fodder helps preserve its quality and avoid spontaneous combustion during storage in hay stacks. Another example is wood, which needs to be dried before use. Many studies have investigated the application of microwave energy to speed up drying (Manickavasagan, et al. 2006, Setiady, et al. 2009).

The effects of microwave heating must be considered as the simultaneous diffusion of heat and moisture through a material (Brodie 2007). Essentially, the theory of combined heat and moisture diffusion (Henry 1948, Brodie 2007) during microwave heating implies that two independent waves of heat and moisture vapour propagate through the material ...