Mechanical properties and leaching modeling of activated incinerator bottom ash in Portland cement blends.

In the present study the evolution of mechanical strength and the leaching behavior of major and trace elements from activated incinerator bottom ash/Portland cement mixtures were investigated. Chemical and mechanical activation were applied with the purpose of improving the reactivity of bottom ash in cement blends. Chemical activation made use of NaOH, KOH, CaCl(2) or CaSO(4), which were selected for the experimental campaign on the basis of the results from previous studies. The results indicated that CaCl(2) exhibited by far the best effects on the evolution of the hydration process in the mixtures; a positive effect on mechanical strength was also observed when CaSO(4) was used as the activator, while the gain in strength produced by KOH and NaOH was irrelevant. Geochemical modeling of the leaching solutions provided information on the mineral phases responsible for the release of major elements from the hardened materials and also indicated the important role played by surface sorption onto amorphous Fe and Al minerals in dictating the leaching of Pb. The leaching of the other trace metal cations investigated (Cu, Ni and Zn) could not be explained by any pure mineral included in the thermodynamic database used, suggesting they were present in the materials in the form of complex minerals or phase assemblages for which no consistent thermodynamic data are presently available in the literature.

[1]  C. Shi,et al.  Pozzolanic reaction in the presence of chemical activators. Part I. Reaction kinetics , 2000 .

[2]  T Sabbas,et al.  Management of municipal solid waste incineration residues. , 2003, Waste management.

[3]  J. M. Chimenos,et al.  Combined use of MSWI bottom ash and fly ash as aggregate in concrete formulation: environmental and mechanical considerations. , 2009, Journal of hazardous materials.

[4]  C S Poon,et al.  Influences of chemical activators on incinerator bottom ash. , 2009, Waste management.

[5]  Z. Giergiczny Effect of some additives on the reactions in fly ASH-Ca(OH)2 system , 2004 .

[6]  X. Pu Investigation on pozzolanic effect of mineral additives in cement and concrete by specific strength index , 1999 .

[7]  C. Zevenbergen,et al.  Mechanism and Conditions of Clay Formation During Natural Weathering of MSWI Bottom Ash , 1996 .

[8]  A Polettini,et al.  Physical and mechanical properties of cement-based products containing incineration bottom ash. , 2003, Waste management.

[9]  Caijun Shi,et al.  Pozzolanic reaction in the presence of chemical activators: Part II — Reaction products and mechanism , 2000 .

[10]  J. Meima,et al.  The leaching of trace elements from municipal solid waste incinerator bottom ash at different stages of weathering , 1999 .

[11]  Alessandra Polettini,et al.  Acid neutralisation capacity and hydration behaviour of incineration bottom ash–Portland cement mixtures , 2002 .

[12]  Thomas Astrup,et al.  Geochemical modeling of leaching from MSWI air-pollution-control residues. , 2006, Environmental science & technology.

[13]  D. Damidot,et al.  Thermodynamic investigation of the CaOAl2O3CaSO4H2O system at 25°C and the influence of Na2O , 1993 .

[14]  Carl D. Palmer,et al.  Solubility of ettringite (Ca6[Al(OH)6]2(SO4)3 · 26H2O) at 5–75°C , 1999 .

[15]  C. Poon,et al.  Pozzolanic properties of reject fly ash in blended cement pastes , 2003 .

[16]  F. Morel,et al.  Surface Complexation Modeling: Hydrous Ferric Oxide , 1990 .

[17]  M. Kersten,et al.  Aqueous solubility diagrams for cementitious waste stabilization systems. 1. The C-S-H solid-solution system , 1996 .

[18]  Caijun Shi,et al.  Acceleration of the reactivity of fly ash by chemical activation , 1995 .

[19]  H. D. Sloot,et al.  Release of major elements from recycled concrete aggregates and geochemical modelling , 2009 .

[20]  B. Lothenbach,et al.  Thermodynamic modelling of the hydration of Portland cement , 2006 .

[21]  B. Pacewska,et al.  Investigations of cement early hydration in the presence of chemically activated fly ash , 2008 .

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

[23]  C. Shi,et al.  Comparison of different methods for enhancing reactivity of pozzolans , 2001 .

[24]  Rob N.J. Comans,et al.  Geochemical modeling of weathering reactions in municipal solid waste incinerator bottom ash , 1997 .

[25]  J. J. Morgan,et al.  Aquatic Chemistry: Chemical Equilibria and Rates in Natural Waters , 1970 .

[26]  H. A. van der Sloot,et al.  Process identification and model development of contaminant transport in MSWI bottom ash. , 2002, Waste management.

[27]  Chris Zevenbergen,et al.  Geochemical factors controlling the mobilization of major elements during weathering of MSWI bottom ash , 1994 .

[28]  A Polettini,et al.  Chemical activation in view of MSWI bottom ash recycling in cement-based systems. , 2009, Journal of hazardous materials.

[29]  Alessandra Polettini,et al.  The effect of Na and Ca salts on MSWI bottom ash activation for reuse as a pozzolanic admixture , 2005 .

[30]  J. Meima,et al.  Application of Surface Complexation/Precipitation Modeling to Contaminant Leaching from Weathered Municipal Solid Waste Incinerator Bottom Ash , 1998 .

[31]  Jueshi Qian,et al.  Activation of blended cements containing fly ash , 2001 .

[32]  B. Quénée,et al.  Behaviour of cement-treated MSWI bottom ash. , 2001, Waste management.

[33]  Pa Rosskopf,et al.  Effect of Various Accelerating Chemical Admixtures on Setting and Strength Development of Concrete , 1975 .

[34]  Jingyu Zhong,et al.  Activation of fly ash and its effects on cement properties , 1999 .

[35]  J. Pera,et al.  Use of incinerator bottom ash in concrete , 1997 .

[36]  D. Mallants,et al.  Geochemical modeling of leaching of Ca, Mg, Al, and Pb from cementitious waste forms , 2010 .

[37]  Christopher R. Cheeseman,et al.  Novel cementitious materials produced from incinerator bottom ash , 2008 .

[38]  Alain Ehrlacher,et al.  The use of thermal analysis in assessing the effect of temperature on a cement paste , 2005 .

[39]  Nick R. Buenfeld,et al.  Differential acid neutralisation analysis , 1999 .

[40]  J. E. Krzanowski,et al.  Particle Petrogenesis and Speciation of Elements in MSW incineration Bottom Ashes , 1994 .

[41]  Caijun Shi,et al.  A calorimetric study of early hydration of alkali-slag cements , 1995 .

[42]  Jiri Hyks,et al.  Long-term leaching from MSWI air-pollution-control residues: leaching characterization and modeling. , 2009, Journal of hazardous materials.

[43]  D. Damidot,et al.  Thermodynamic investigation of the CaOAl2O3CaSO4H2O system at 50°C and 85°C , 1992 .