This fermentation residue dryer is used in biogas plants. The residues are first pressed, giving them the consistency of moist peat. Then they are chopped up by a rotor and dispensed to the belt dryer by a back-and-forth pivoting valve arm. For this to work smoothly, the developers used igubal® rod end bearings in the rotor and the valve arm. Since they require no lubrication, they are absolutely maintenance-free and also resistant to the chemically aggressive fermented residues.