The research focuses on the performances of a traditional single stream MBT for SRF production suitable for co-combustion in a cement kiln. Bio-drying of the residual waste is followed by mechanical refining in order to fulfil the quality requirements by the cement kilns. The residues arising from the mechanical refining section are landfilled in a nearby bioreactor-landfill, where landfill gas is collected for electric energy recovery. A detailed mass balance of the system is presented, followed by a Life Cycle Assessment.
To maximize biogas yields, adequate substrate mixing during anaerobic digestion (AD) is of particular importance. In dry AD this may be hampered by high solid matter Contents causing a pronounced wear of mixing tools and triggering costly maintenance interruptions. This study aims at the development of a rotating drum fermenter (RDF) to overcome these problems. As a first step towards the development of a full-scale RDF for dry AD of biowaste, particular attention was given to the mixing performance. Therefore, a lab-scale RDF was constructed from acrylic glass to allow visual inspection of the radial mixing process.
The use of landfills for the disposal of municipal solid waste (MSW) has many technical and regulatory limits. An interesting solution is to recover the bales that have been previously stored in a landfill. After specific mechanical biological treatments (MBT), the contents of the bales can be used to produce a solid recovered fuel (SRF) that can be used for energy purposes. The possibility of producing SRF fuels from a landfill in northern Italy has been studied and is presented in this paper. The MSW extracted from the landfill, the bio-dried material produced by the waste hypothetically treated in a plant for bio-drying, and the SRF obtained after the extraction of inert materials, metals and glass from the bio-dried material have been characterized. Assessed the waste nature, the potential environmental impact of dioxin release from a possible landfill fire has been analysed, applying the Austal2000 model system.