Common applications of thin layer drying curve equations and their evaluation criteria

In this study, thin layer drying curve equations commonly used in the literature between 2003 and 2013 are systematically discussed and evaluated in terms of their applications and selection for thin layer drying processes by considering the model evaluation criteria. As a result of this study, serious complications, confusions, and conflicts in the applications of thin layer drying curve equations and their evaluation criteria are noticed. Consequently, it is recommended that the drying curve equations should be applied in accordance with the forms commonly used in the literature. Also, it is determined that the following drying curve equations give the best results for thin layer drying processes which are the Midilli-Kucuk, Page, Logarithmic, Two-term, Wang and Singh, Approximation of diffusion, Modified Henderson and Pabis, Modified Page, Henderson and Pabis, Two-term exponential, and Verma et al.