Study and development of paddy drying system with pneumatic and screw

Abstract

Moisture content has a marked influence on all aspects of paddy and rice quality. These issues also have significantly importance for rice industry and economy of Thailand. Many drying process such as spouted bed technique and fluidized bed technique are extremely studied in terms of instrument design and energy consumption. However, these drying processes were not suitable for high economic rice. Because of these processes performed highly damaged kernels during drying process. The objective of this project, we proposed the alternative drying system that perform low damaged paddy kernels. We also were design and fabrication drying system for paddy in terms of conveyer pipe. This machine have the performance including feed rate approximately 22.83 kg/hr., drying temperature 30-120ºC, air velocity 0-1.5 m/s, drying time 14.64-16.91 min and energy consumption 6.02 baht/hr. We improved our machine by drying the RD41 paddy at moisture content 28 (%w.b.). We also setup drying temperatures 40°C, 45°C, 50°C, 55°C and 60°C with air velocities 0.7m/s, 1.0m/s and 1.5m/s. We found that all drying temperatures have the final moisture content lower than 15 (%w.b.) and percentage of complete paddy after drying (HRY-paddy) more than 96%. For the kernels quality, we found that HRY-Brown rice tend to increase with drying temperature increased. We also found that HRY-Unbroken kernels for polishing tend to decrease between drying temperature 40°C - 50°C for air velocities 0.7m/s and 1.5m/s. Therefore, these results obtained can be such a high potential approach that can be used for further developing into rice economy and industry of Thailand.