1991 Volume 53 Issue 1 Pages 55-63
A far-infrared panel heater was used experimentally for drying rough rice. The normal infrared absorption spectra of moisture in a rice kernel is 2.9μm, but because the corresponding temperature of the radiated heat is too high, there is concern for heat damage. In the experiment a panel heater with a wavelength of 3.3 to 8μm which heats to much lower than 250°C was used.
Drying tests were conducted with the rice on a dryer with a circulating capacity of 2tons per hour. The mean drying rates were 0.34, 0.57, and 0.77%per hour for cycle times of 31, 16, and 9 minutes respectively. The temperature of the rice was kept below 30°C, but there was a tendency to develop light cracks in the rice after repeated circulation. No heavy cracks formed. The electricity to dry 1kg of rice moisture was 1.535kW·h at minimum, just as in a continuous dryer.
