Properties and microstructure of lightweight aggregate produced from lignite coal fly ash and recycled glass

Abstract The effect of glass addition on the processing, physical properties and microstructure of lightweight aggregate made from lignite coal fly ash from the Megalopolis power station in Greece has been investigated. Fly ash/glass mixes have been rapidly sintered at temperatures between 1040 and 1120 °C in a rotary furnace, and the density, water absorption and pellet strength determined. Sintering 60:40 fly ash:waste glass mixes at 1120 °C produced lightweight aggregate with a mean density of 1.35 g/cm 3 , water absorption of ∼16% and crushing strength of 7.3 MPa. Major crystalline phases in sintered materials were quartz (SiO 2 ), albite (NaAlSi 3 O 8 ), moissanite (SiC), hematite (Fe 2 O 3 ), wollastonite (CaSiO 3 ) and diopside (CaMg(Si 2 O 6 )). The work indicates that Megalopolis fly ash combined with waste glass can be used to manufacture lightweight aggregate with properties comparable to commercially available products. Fly ash and glass are potential resources that are currently waste materials in Greece. The processing involving pelletising and sintering in a rotary kiln is similar to that required for other commercially available lightweight aggregates manufactured from shales, clays and slate, and therefore processing costs are expected to be similar. However, avoiding the costs and environmental impacts associated with importing lightweight aggregate or using pumice makes the production of FA/glass lightweight aggregate a viable option.

[1]  V. Ducman,et al.  Lightweight aggregate based on waste glass and its alkali–silica reactivity , 2002 .

[2]  A. Neville.  Properties of Concrete , 1968 .

[3]  Martin Porter,et al.  Packaging and Packaging Waste , 2002 .

[4]  N. Kouloumbi,et al.  Chloride corrosion of steel rebars in mortars with fly ash admixtures , 1992 .

[5]  I. M. Anagnostopoulos,et al.  Utilization of lignite power generation residues for the production of lightweight aggregates. , 2009, Journal of hazardous materials.

[6]  A. Filippidis,et al.  Environmentally Important Elements in Fly Ashes and Their Leachates of the Power Stations of Greece , 2002 .

[7]  Nikolaos Koukouzas,et al.  Mineralogy and geochemistry of Greek and Chinese coal fly ash , 2006 .

[8]  Jyh-Dong Lin,et al.  Production of lightweight aggregates from mining residues, heavy metal sludge, and incinerator fly ash. , 2007, Journal of hazardous materials.

[9]  Vagelis G. Papadakis,et al.  Greek supplementary cementing materials and their incorporation in concrete , 2005 .

[10]  E. Voudrias,et al.  Leachability of heavy metals in Greek fly ash from coal combustion , 1998 .

[11]  C. Samara,et al.  Size distribution of trace elements and polycyclic aromatic hydrocarbons in fly ashes generated in Greek lignite-fired power plants. , 2003, The Science of the total environment.

[12]  V. Kaloidas,et al.  Carbonation and porosity of mortar specimens with pozzolanic and hydraulic cement admixtures , 1994 .

[13]  Joanna Papayianni,et al.  Use of a high-calcium fly ash in blended type cement production , 1993 .

[14]  N. Kouloumbi,et al.  The anticorrosive effect of fly ash, slag and a Greek pozzolan in reinforced concrete , 1994 .

[15]  J. Papayianni,et al.  Residual mechanical properties of heated concrete incorporating different pozzolanic materials , 1991 .

[16]  A. Moutsatsou,et al.  Participation of coloured glass cullet in cementitious materials , 2005 .

[17]  Luisa Barbieri,et al.  Bulk and sintered glass-ceramics by recycling municipal incinerator bottom ash , 2000 .

[18]  Panagiotis Grammelis,et al.  Quality characteristics of Greek fly ashes and potential uses , 2007 .

[19]  A. Moutsatsou,et al.  The utilization of Ca-rich and Ca–Si-rich fly ashes in zeolites production , 2006 .

[20]  Mohsen G. Kashi,et al.  SYNTHETIC LIGHTWEIGHT AGGREGATES FROM FLY ASH AND WASTE PLASTICS , 2001 .

[21]  Hisahide Kinari,et al.  Manufacturing of Artificial Lightweight Aggregate Utilizing Coal Fly Ash (Recycling Technology of Waste Material) , 1994 .

[22]  Christopher R. Cheeseman,et al.  Properties and microstructure of lightweight aggregate produced from sintered sewage sludge ash , 2005 .

[24]  Glykeria Kakali,et al.  Portland-limestone cements. Their properties and hydration compared to those of other composite cements , 2005 .

[25]  K. Michailidis,et al.  Mineralogy, geochemistry and physical properties of fly ash from the Megalopolis lignite fields, Peloponnese, Southern Greece , 1996 .

[26]  A. Filippidis,et al.  MORPHOLOGY AND TRACE ELEMENT CONTENTS OF THE FLY ASH FROM MAIN AND NORTHERN LIGNITE FIELDS, PTOLEMAIS, GREECE , 1994 .

[27]  S. Antiohos,et al.  Investigating the role of reactive silica in the hydration mechanisms of high-calcium fly ash/cement systems , 2005 .

[28]  T. Taylor Eighmy,et al.  Petrogenesis of municipal solid waste combustion bottom ash , 1999 .

[29]  A. Filippidis,et al.  Mineralogical and chemical investigation of fly ash from the Main and Northern lignite fields in Ptolemais, Greece , 1992 .

[30]  A. Filippidis,et al.  GIS-type zeolite synthesis from Greek lignite sulphocalcic fly ashes promoted by NaOH solutions , 2003 .

[31]  D. Karangelos,et al.  Radiological characteristics and investigation of the radioactive equilibrium in the ashes produced in lignite-fired power plants. , 2004, Journal of environmental radioactivity.

[32]  J. M. Chimenos,et al.  Characterization of the bottom ash in municipal solid waste incinerator , 1999 .

[33]  Tiziano Manfredini,et al.  Vitrification of fly ash from thermal power stations , 1997 .

[34]  H. Kiyama,et al.  Rapid Determination of the Tensile Strength of Rocks with Irregular Test Pieces , 1965 .