Thermal Treatment of Solid Wastes Using Drying Technologies: A Review

The proper treatment of organic or inorganic solid wastes is necessary for economic and environmental interests. Added-value by-products of market interest can be obtained through the recovery, reuse, and treatment of solid wastes, which are otherwise discarded inappropriately in large quantities into the environment. In this review, the drying process is presented as an alternative environmental technology for the thermal treatment of residues of different natures from different origins. The main techniques applied to solid waste drying are described and, in parallel, the most relevant studies found in the literature for this theme are analyzed. Moreover, the main dryers currently used are presented, as well as their most important characteristics. Some general aspects of the thermal and energetic performance of these dryers fundamental for process feasibility analysis are also discussed in this review. Essential aspects of the solid waste drying process are primarily presented with the purpose of showing the particularities that this approach offers when it comes to putting the theory into practice.