Exergy Transfer Analysis of Biomass and Microwave Based on Experimental Heating Process

Exergy transfer and microwave heating performances of wheat straw particles as affected by microwave power (250, 300, and 350 W), feeding load (10, 30, and 50 g), and particle size (0.058, 0.106, and 0.270 mm) were investigated and detailed in this study. The results show that when the microwave power increased from 250 to 350 W, the average heating rate increased in the range of 23.41–56.18 °C/min with the exergy transfer efficiency increased in the range of 1.10%–1.89%. When the particle size increased from 0.058 to 0.270 mm, the average heating rate decreased in the range of 20.59–56.18 °C/min with the exergy transfer efficiency decreased in the range of 0.70%–1.89%. When the feeding load increased from 10 to 50 g, the average heating rate increased first and then decreased in the range of 5.96–56.18 °C/min with the exergy transfer efficiency increased first and then decreased in the range of 0.07%–1.89%. The highest exergy transfer efficiency was obtained at a microwave power of 300 W, feeding load of 30 g, and particle size of 0.058 mm.