DEVELOPMENT AND EVALUATION OF A GREEN-HOUSE TYPE SOLAR DRYER FOR DRYING EAR AND SHELLED CORN

A green house-type solar dryer was developed at the experimen­tal farm of Rice Mechanization Center (R. M. C.), Meet El-Dyba, Kafer El-Sheikh Governorate. The dryer was tested and evaluated for drying high moisture ear and shelled corn of variety (three way - cross 310) and compared with natural sun drying method. The results show that, the de­veloped dryer was able to dry ear corn from an initial level of 29.85% to a final level of 14.26% in 84 hours as compared to 187 hours for natural sun drying method. The corresponding drying times for shelled corn from an initial grain moisture level of 19.87% to a final level of 14.13% were 18 and 34 hours respectively. Quality evaluation tests of the dried ear and shelled corn showed a lower percentage of kernels stress cracks for the solar dried kernels compared with natural sun drying of ear corn giving the lowest percent­age of stress cracks kernels (SC) (9.10%).. While the natural sun drying produced the highest percentage of (SC) kernels (23.1 %). However the grain germination tests showed an average percentage of over 90% for both solar and natural sun drying methods of ear and shelled corn. Cost analysis of the solar dryer showed a total cost of 28.76 LE/ ton for drying ear corn from an initial grain moisture level of 29.85% to a final moisture level of 14.26% and 8.00 LE / ton for drying shelled corn from an initial level of 19.87% to a final level of 14.13%. For the two stage drying system reduction the estimated drying cost from initial moisture level of 29.85% to a final level of 19.87% for ear corn and from initial level of 19.87 to a final level of 14.13% for shelled corn was about 20.68 LE/ton.