The present disclosure provides, among other things, a system and process for drying a biosolid or sludge, such as wastewater sludge. The system and method include a fluidized bed dryer in which the sludge is dried. The fluidized bed includes bed media. In particular examples, the bed media is different than the sludge. The system and method can include additional features, such treating the sludge using a thermochemical process in a thermochemical reactor, such as a gasifier, to produce a fuel. The fuel is then combusted to produce energy and heat. The heat is recycled to the drier to help dry sludge. In particular examples, sludge input to the dryer is not first treated using a high-pressure dewatering technique. In some embodiments, the system and method include an anaerobic digester coupled to a combustion unit coupled to the dryer.