Process for the treatment of sewage sludge from a biological waste water purification plant

摘要

a method for the disposal of sludge from a biological sewage treatment plant in which the thickened sludge further dewatered and in a centrifuge (15) using saturated steam, preferably in the pressure range of 1 - 15 bar at a temperature of 100 ° C - 200 ° C, is at least partially thermally decomposed, the centrate of the compound under saturated steam centrifuge (15) via a lock (18) is discharged and immediately thereafter subjected to sulfide precipitation of heavy metals (19). In the centrifuge (15) separated solids are thereby simultaneously discharged via ports (28) and optionally a drying (33) and at least partially an internal, for example a fluidized bed combustion (23) to produce steam (17) to the centrifuge (15) subjected to wherein the steam is completely recycled and the Schleusenabdampf for heating air (30) is used, to which condensate formed is supplied to the preliminary sedimentation tank (5) of the sewage treatment plant, whereby a reduction in energy requirements and reduced environmental load is achieved.