Performance evaluation of modified hybrid solar dryer for paddy seed

Abstract

A modified hybrid solar dryer having capacity of 500 kg was constructed to carry out the study. Performance of the dryer was evaluated based on the drying rate, collector performance, collector efficiency, drying efficiency and quality of paddy (Oryza Sativa L.) seed. A 0.50 kW, 220 V centrifugal variac connected blower was used to control air flow. The drying air was heated up in the solar collector and passed to the drying chamber. Seeds were collected having initial moisture content of 23.86% (wb). Tetrazolium and standard germination tests were used to evaluate seed. This study found maximum germination (86%) percentage at 44°C and viability at that temperature was 97.5%. The germination percentage decreases with increasing drying temperature and 44°C temperature is completely safe for paddy seeds. This study also observed that amongst nine models Page model is best fitted model based on highest R2 and lowest RMSE values.