Evaluation beyond a Review: Developments in Heat Pump Dryers from the Recent Past to the Present

Abstract

Heat pump dryers provide tremendous advantages in the drying sector, an energy-intensive process. Studies on heat pump dryers for many years still maintain their popularity today. The presented study deals with the developments in heat pump dryers in recent years. Only 82 of the studies that contributed to the literature between 1997 and 2022 were examined in this framework. This study firstly focused on studies examining the performance of heat pump dryers used in food drying, mainly in which ambient air is used as a source. In the following, this review summarizes the results from studies on chemical heat pump dryers and drum heat pump dryers for drying clothes. This review also covers applications that integrate solar and infrared, which increase the efficiency of heat pump dryers, and studies using exergy analysis. The examined studies were evaluated in terms of performance parameters such as coefficient of performance, specific moisture extraction rate, drying time, exergy efficiency, and destruction. This review study shows that improvements in heat pump dryers will reduce drying time and operating costs. Thus, an important guide study has been put forward for researchers working on this subject and the sector leaders.