Innovation of a Prototype Post-harvest Rice Grain Dryer Machine Through the Application of Joule Heating

Abstract

In the Philippines, the method of sun-drying often exposes rice grains to numerous vulnerabilities, leading to severe damage to rice grains. Despite several innovations in dryer machines, unfavorable combustible heat sources were still a concern. Thus, this study aimed to develop a prototype grain dryer machine by utilizing joule heating with the use of nichrome wire to enhance the drying efficiency and effectiveness of the machine.

For the research design, a true experimental approach was employed to assess the machine's ability to dry rice grains compared to the traditional method of drying. This machine effectively integrates a PID control system, complemented with a nichrome wire and air blower, to maintain a uniform drying environment, fluctuating within the range of 50 to 60 degrees Celsius to attain the desired moisture content of 14% and below.

Results of the rigorous testing process verified that the prototype effectively reached and maintained the optimal drying temperature of 60°C, with an average energy consumption of Php 1.146 for each session lasting 1 hour and 40 minutes. The accumulated value p-value from the Analysis of Variance (Single Factor) was greater than 0.05, indicating that the air distribution within the chamber was uniform. The machine successfully dried the rice grains to the desired moisture content of 14% and below consistently across the batch loads of 5, 10, and 15 kg. Additionally, machine-dried rice grains showed significant advantages over sun-dried grains in terms of moisture content and drying time while having a lower production cost.

Thus, the study concludes that the developed drying machine holds promise for addressing post-harvest drying challenges in the agricultural sector. Its efficient performance, shorter drying time, and lower production cost make it a viable alternative to traditional sun-drying methods, offering significant benefits for preserving rice grains and improving overall post-harvest processes.