Analysis and Model Exploration of Paddy Hot Air Drying Process

To explore the effects of different drying processes on the drying characteristics and quality of paddy，a self-made paddy drum hot-air drying device was used for hot-air drying experiments with drying temperature，initial moisture content，and drum speed as influencing factors，and paddy cracking rate，protein content，fatty acid value，and taste value as evaluation indicators. Single factor and orthogonal experimental methods were used to explore the effects of different factors on the drying characteristics and quality of paddy，and the optimal drying process for paddy was analyzed. The applicability of six drying mathematical models in hot-air drying was compared. The results showed that drying temperature had the greatest impact on the drying characteristics and quality of paddy，followed by initial moisture content and drum speed. As the drying temperature was increased，the drying rate of paddy was increased，and the cracking rate，protein content，fatty acid value，and taste value of paddy were increased，while the taste value was decreased. The moisture content of paddy was reduced to 18% by natural drying method，and the drying quality of paddy was the best at drying temperature of 40 ℃ and rotating speed of roller of 30 r/min. The optimal drying mathematical model was Wang and Singh model. As the drying temperature was increased，the effective diffusion coefficient of paddy moisture was also increased. When the drying temperature was increased from 40 ℃ to 60 ℃，its effective diffusion coefficient of paddy moisture was increased from 9.433×10-11 to 1.885×10-10，and the drying activation energy of paddy was 30.153 kJ. © 2024 Chinese Society of Agricultural Machinery. All rights reserved.