title: Sewage sludge drying process integration with a waste-to-energy power plant.
abstract: Dewatered sewage sludge from Waste Water Treatment Plants (WWTPs) is encountering increasing problems associated with its disposal. Several solutions have been proposed in the last years regarding energy and materials recovery from sewage sludge. Current technological solutions have relevant limits as dewatered sewage sludge is characterized by a high water content (70-75% by weight), even if mechanically treated. A Refuse Derived Fuel (RDF) with good thermal characteristics in terms of Lower Heating Value (LHV) can be obtained if dewatered sludge is further processed, for example by a thermal drying stage. Sewage sludge thermal drying is not sustainable if the power is fed by primary energy sources, but can be appealing if waste heat, recovered from other processes, is used. A suitable integration can be realized between a WWTP and a waste-to-energy (WTE) power plant through the recovery of WTE waste heat as energy source for sewage sludge drying. In this paper, the properties of sewage sludge from three different WWTPs are studied. On the basis of the results obtained, a facility for the integration of sewage sludge drying within a WTE power plant is developed. Furthermore, energy and mass balances are set up in order to evaluate the benefits brought by the described integration.
authors.affiliation: Department of Industrial Engineering, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy. Electronic address: augusto.bianchini@unibo.it.
authors.forename: A
authors.initials: A
authors.lastname: Bianchini
authors.affiliation: Department of Industrial Engineering, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy. Electronic address: luca.bonfiglioli7@studio.unibo.it.
authors.forename: L
authors.initials: L
authors.lastname: Bonfiglioli
authors.affiliation: Department of Industrial Engineering, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy. Electronic address: marco.pellegrini3@unibo.it.
authors.forename: M
authors.initials: M
authors.lastname: Pellegrini
authors.affiliation: Department of Industrial Engineering, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy. Electronic address: cesare.saccani@unibo.it.
authors.forename: C
authors.initials: C
authors.lastname: Saccani
mesh_terms: D003890:Desiccation; D004736:Energy-Generating Resources; D011210:Power Plants; D012037:Refuse Disposal / Q000379:methods*; D012722:Sewage / Q000032:analysis*; D014867:Water / Q000032:analysis
chemical_list: D012722:Sewage; D014867:Water
keywords: Energy recovery; Plant integration; Sewage sludge; Waste to energy power plant; Waste water treatment plant