Theoretical and experimental investigation on agglomeration phenomena in a SRF-fired fluidized bed waste-to-energy plant

Several technologies for waste incineration are widespread worldwide such as furnace grate, rotary kiln and fluidized bed. In a fluidized bed combustor (FBC), a bed of sand, combustion ash, or other sand-like material is suspended in an upward flowing airstream. The high turbulence created en- hances combustion and promotes an efficient heat transfer and uniform mixing. SRF (Solid recovered fuel) represents the evolution of RDF (refuse derived fuel) and it is generally burned in Waste-to-Energy (WtE) plants. Among the causes of FBC dysfunction, agglomeration is the most important. It is the result of the in-bed formation of low melting point eutectic mixtures through the reaction of mostly alkali compounds of the waste feed with the silica bed materials. The particle growth of the bed material lead to de-fluid- ization of the bed with a consequent plant shutdown. Thus, an appropriate prediction of the agglomeration characteristics is essential. The aim of the study was to investigate the agglomeration phenomena of a FBC by means of a theoretical and experimental investigation. For this aim, the case study of the WtE plant of Massafra (TA) in the South Italy was considered.