There are two major types of dryers: Direct and Indirect Dryers. Direct Dryers utilize hot air as the mechanism of water evaporation while Indirect Dryers utilize rotating heated surfaces to transmit heat into the wet product. The most common dryers are Direct Dryers that use natural gas to heat the drying air. It is important to keep in mind that there’s no one-size-fits-all dryer option that’s used for every application. In this article, we will concentrate on different Direct Dryers that can dry a wet solid feed material.