New waste based clinkers: Belite and lime formulations

This work describes the formulation of new belite-based (CR2) and lime-based (CR3) cementitious materials derived from industrial wastes, such as sludges (generated in the Al-anodising and surface coating industrial processes, potable water filtration/cleaning operations and in marble sawing processes) and foundry sand. Powder mixtures were prepared and fired at different temperatures. For comparison, similar formulations were prepared with pre-treated and commercially available natural raw materials and processed in similar conditions. The thermal process was followed by differential scanning calorimetry (DSC) and high-temperature powder X-ray diffraction (HT-XRD) studies. The CR2 clinker was found to contain belite as the main cementitious phase, the main polymorph being identified by NMR. The CR3 clinker contained common cementitious phases, such as C{sub 3}A and C{sub 3}S, but free lime and calcium aluminium oxide sulphates were also identified by high temperature XRD and NMR. Then the corresponding cement was prepared and the evolution of the mechanical strength with time was evaluated. The lime-based cement obtained from wastes shows a stronger hardening character than the standard material, which tends to show dusting phenomena due to the presence of a reasonable amount of free lime (as the result of its expansive reaction with ambient moisture). Some fluxing impuritiesmore » (e.g. alkalis) present in the waste materials improve the overall reactivity of the mixture and induces the combination of the lime in CR3. Raman, XPS and FIB techniques were used to fully characterise the aged cements.« less

[1]  B. Reynard,et al.  Raman Spectroscopic Investigations of Dicalcium Silicate: Polymorphs and High‐Temperature Phase Transformations , 2005 .

[2]  T. Kwon,et al.  FT-Raman spectroscopy of calcium hydroxide medicament in root canals. , 2004, International endodontic journal.

[3]  M. Kawamura,et al.  Chloride Permeability Of Concrete Containing A Flyash And A Blastfurnace Slag , 1988 .

[4]  R. Orlando,et al.  Structural and vibrational properties of solid Mg(OH)2 and Ca(OH)2 – performances of various hamiltonians , 2001 .

[5]  William B. White,et al.  Characterization of diamond films by Raman spectroscopy , 1989 .

[6]  G. C. Allen,et al.  X-ray photoelectron spectroscopy of the cement clinker phases tricalcium silicate and β-dicalcium silicate , 2003 .

[7]  J. Labrincha,et al.  Mechanical behaviour of Portland cement mortars with incorporation of Al-containing salt slags , 2000 .

[8]  C. Deng,et al.  Ageing of oilfield cement at high humidity: a combined FEG-ESEM and Raman microscopic investigation , 2002 .

[9]  Q. Williams,et al.  Vibrational spectra of Mg(OH)2 and Ca(OH)2 under pressure , 1989 .

[10]  N. Vagenas,et al.  Calcium carbonate phase analysis using XRD and FT-Raman spectroscopy , 2000 .

[11]  W. Stickle,et al.  Handbook of X-Ray Photoelectron Spectroscopy , 1992 .

[12]  R. Buchanan,et al.  Lattice vibration spectra of Mg(OH)2 and Ca(OH)2 , 1963 .

[13]  D. Michel,et al.  High-resolution solid-state NMR of silicates and zeolites , 1987 .

[14]  J. Labrincha,et al.  Incorporation of Sludges in Light Expanded Clay Aggregates , 2004 .

[15]  I. Odler.  Special Inorganic Cements , 2000 .

[16]  M. A. Yurdusev,et al.  USE OF ZEOLITE, COAL BOTTOM ASH AND FLY ASH AS REPLACEMENT MATERIALS IN CEMENT PRODUCTION , 2004 .

[17]  Erlangen,et al.  Light-weight cellular ceramics from biologically-derived preforms , 2000 .

[18]  H. J. Jakobsen,et al.  Characterization of white Portland cement hydration and the C-S-H structure in the presence of sodium aluminate by 27Al and 29Si MAS NMR spectroscopy , 2004 .

[19]  Á. G. Torre,et al.  Mineralogical phase analysis of alkali and sulfate bearing belite rich laboratory clinkers , 2007 .

[20]  H. Panepucci,et al.  29Si and 27Al high-resolution NMR characterization of calcium silicate hydrate phases in activated blast-furnace slag pastes , 2001 .

[21]  J. Labrincha,et al.  Incorporation of alumina rich residues in refractory bricks , 2000 .

[22]  David Carrington,et al.  Limes And Lime Mortars—Part One , 1995 .

[23]  S. Sahu,et al.  Preparation of sulphoaluminate belite cement from fly ash , 1994 .

[24]  J. Labrincha,et al.  Ceramic formulations prepared with industrial wastes and natural sub-products , 2006 .

[25]  J. Ferreira,et al.  Mullite-Alumina Refractory Ceramics Obtained from Mixtures of Natural Common Materials and Recycled Al-Rich Anodizing Sludge , 2002 .