Energy and exergy analysis of solar convective drying under arid climate of hydroxide sludge

In the industry, the drying process is a fundamental operation that consumes a lot of energy and time. This method is used in order to manage the huge mass and volume produced by the drinking water treatment plants as well as the reduction of transport costs. The present work aims to study the drying kinetics of hydroxide sludge in order to obtain the drying curves at different temperatures (40, 60 and 80°C) and drying air flows of 150 and 300 m3.h−1 as well as energy and exergy efficiency analysis. Based on the results, it can be concluded that the increase in drying temperature results in a shorter drying time. In order to evaluate the solar dryer performance, an energy analysis was carried out. An analysis of the exergy at the drying chamber and evaporation transfer was performed. The convective dryer's energy and exergy efficiencies are ranged from 2.72 to 5.07% and 42 to 63% respectively.