the drying process of the printed paper web enrich the drying medium gas and is fed to the solvent recovery unit 5 5 u2032 in order to separate out the individual oil constituents of the solvent gas mixture in this case the drying medium used for the drying system 9 is the exhaust gases 11 from an internal combustion engine 12 the exhaust gas 11 the temperature of which is controlled by the combustion process of the internal combustion engine 12 is suitable as a drying medium for drying the paper web the mechanical energy resulting from the internal combustion engine 12 can for example be used via a generator 13 for the production of electrical energy 14 and this electrical energy can be used to operate the recovery unit 5 5 u2032 the drying system 9 and or further technical equipment belonging to the apparatus 1 some of the exhaust gas 11 from the internal combustion engine 12 can be fed to an absorption refrigerating machine 15 for the further optimization of the overall energy balance the refrigeration output refrigeration energy 16 resulting from the absorption refrigerating machine 15 is in this case led to the heat exchangers 2 2 u2032 3 3 u2032 4 4 u2032 the oil recovery unit 5 5 u2032 for cooling further machines 17 and or for air conditioning parts of the building furthermore via a control or regulating element 18 the distribution of the.