Abstract
Exergoeconomic analysis has been used as a powerful tool to study and optimize various types of energy-related systems. In this study, we use the specific exergy cost (SPECO) method to calculate exergy-related parameters and display cost flows for all streams and components in a gas engine–driven heat pump drying system based on the experimental data. We analyze and evaluate the performance of the drying system components and the drying process for three different medicinal and aromatic plants from an exergoeconomic point of view. We also investigate the effect of varying dead (reference) state temperatures on exergoeconomic performance parameters for the drying system components and drying process. Although the condenser and drying chamber of the gas engine–driven heat pump dryer were significantly affected by the ambient temperature, the gas engine was slightly influenced by the ambient temperature. At low ambient temperatures, the exergy rates increased and the most effective performance obtained from this dryer was at 0°C. The performance of the drying process also increased at low ambient temperatures. This study demonstrated that exergoeconomic analysis can provide more information than exergy analysis, and the results obtained from the exergoeconomic analysis provided cost-based information, suggesting potential locations for drying system improvement.
ACKNOWLEDGMENTS
The authors are grateful for the financial support provided by the project entitled “Design, Test and Performance Evaluation of a Gas Engine-Driven Solar Assisted Band Conveyor Heat Pump Drying System” under project no. 106M482 by the Scientific and Technological Research Council of Turkey (TUBITAK). The authors also thank the reviewers for their valuable comments, which have been utilized in improving the quality of the article, and Associate Editor Yoshinori Itaya for the quick review process.
Notes
a Results for drying of Foeniculum vulgare.
b Results for drying of Malva sylvestris L.
c Results for drying of Thymus vulgaris.