Influence of drying air velocity characteristics on paddy drying

Abstract

The objective of this research was to study the influence of drying air velocity characteristics on paddy drying. The pneumatic dryer prototype was used in this study. Test drying 15 kg of Hom Pathum paddy at 22 – 25% initial wet basis moisture content was tested drying under the drying air temperature 80OC until its moisture is 14% wet basis with the two drying air velocity characteristics. The first characteristic of drying air velocity is constant at 12.80 m/s and another is reduced velocity every 15 minutes throughout the test process from 12.80 - 8.44 m/s. Drying in a vertical tube with a diameter of 3.81 cm and height 1 m for study the drying behavior, drying rate (DR), specific energy consumption (SEC), and thermal efficiency of drying. The results showed that drying with constant air velocity gives a shorter time, higher drying rate, lower primary SEC consumption, and higher thermal efficiency than drying with reducing air velocity.