Abstract: The invention relates to a process and apparatus for treating biogenic residues, particularly sludges, preferably in the area of a clarification plant. Biogenic residues with a variable dry substance are subjected to aerobic drying until an energy-independent thermal treatment can be carried out. During the drying process, evaporated water is discharged in an odor-free condition without releasing freely volatile components, the dried sludge is intermediately stored a number of times and then utilized in preferably a number of successive thermal treatment steps. The two-stage cleaning of the stream of waste gas includes a dust collection unit and an adsorption unit. The waste heat is recycled through a heat exchanger to generate heat and electricity.