Energy and Exergy Performance Evaluation of a Continuous Flow Paddy Dryer Under Varying Drying Air Temperatures
- Awua Tarka Justin1; Kuhe Aondoyila2; & Johnson Audu3
- DOI: 10.5281/zenodo.19956432
- ISA Journal of Engineering and Technology (ISAJET)
This study presents an evaluation of the energy and exergy performance of a continuous flow paddy dryer under varying drying air temperatures (122–126 °C). The drying characteristics, energy utilization, and exergy behaviour of the system were investigated to provide an assessment of dryer performance. The drying process exhibited a predominantly diffusion-controlled mechanism with the moisture ratio decreasing from 0.935 to 0.847, indicating effective moisture removal. Energy analysis showed that the dryer operated at a moderate energy utilization efficiency of approximately 37% having limited sensitivity to temperature variation. Furthermore, the specific energy consumption decreased from 6.8 to 5.9 MJ/kg H₂O with increasing temperature indicating improved energy efficiency at higher operating conditions. Exergy analysis showed that exergy efficiency remained relatively stable at 30.6% within the temperature range of 122–125 °C but decreased to 26.1% at 126 °C. Exergy destruction remained nearly constant at approximately 6.5 suggesting that system losses are primarily governed by inherent design and operational constraints. The results show higher temperatures reduce energy consumption but degrade energy quality. Furthermore, an optimal operating range of 122–125 °C was identified where a balance between drying performance, energy utilization, and exergy efficiency is achieved. The findings provide valuable insights for the optimization and design improvement of continuous flow paddy dryers thereby contributing to enhanced energy efficiency and sustainability in agricultural drying systems.
