Production of pyroxene ceramics from the fine fraction of incinerator bottom ash.
Incinerator bottom ash (IBA) is normally processed to extract metals and the coarse mineral fraction is used as secondary aggregate. This leaves significant quantities of fine material, typically less than 4mm, that is problematic as reuse options are limited. This work demonstrates that fine IBA can be mixed with glass and transformed by milling, calcining, pressing and sintering into high density ceramics. The addition of glass aids liquid phase sintering, milling increases sintering reactivity and calcining reduces volatile loss during firing. Calcining also changes the crystalline phases present from quartz (SiO2), calcite (CaCO3), gehlenite (Ca2Al2SiO7) and hematite (Fe2O3) to diopside (CaMgSi2O6), clinoenstatite (MgSiO3) and andradite (Ca3Fe2Si3O12). Calcined powders fired at 1080°C have high green density, low shrinkage (<7%) and produce dense (2.78 g/cm(3)) ceramics that have negligible water absorption. The transformation of the problematic fraction of IBA into a raw material suitable for the manufacture of ceramic tiles for use in urban paving and other applications is demonstrated.
Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ, UK.
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A
Bourtsalas
Centre for Advanced Structural Ceramics and Department of Materials, Imperial College London, London SW7 2AZ, UK.
L J
LJ
Vandeperre
Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ, UK.
S M
SM
Grimes
Earth Engineering Centre, Columbia University, New York, NY 10027, USA.
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N
Themelis
Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ, UK. Electronic address: c.cheeseman@imperial.ac.uk.
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CR
Cheeseman
D002516:Ceramics / Q000032:analysis*; D060729:Coal Ash / Q000737:chemistry*; D005898:Glass / Q000737:chemistry; D017745:Incineration; D008903:Minerals / Q000032:analysis*; D012037:Refuse Disposal / Q000379:methods*
D060729:Coal Ash; D008903:Minerals; C092478:pyroxene
Ceramics; Energy from waste; Incinerator bottom ash; Pyroxene; Resource efficiency; Sintering