Ceramics-Silikáty 57, (1) 7 - 13 (2013) |
|
SYNTHESIS AND CHARACTERIZATION OF HIGH BELITE SULFOALUMINATE CEMENT THROUGH RICH ALUMINA FLY ASH AND DESULFURIZATION GYPSUM |
Ma Bing, Li Xuerun, Mao Yuyi,
Shen Xiaodong |
State Key Laboratory of Materials-oriented Chemical Engineering, College of Material Science and Engineering,
Nanjing University of Technology, Nanjing 210009, PR China
|
Keywords: Industrial residue, Belite-sulfoaluminate, Fly ash, Desulfurization gypsum, Hydration |
The objective of this study was the preparation and characterization of high belite sulfoaluminate cement (HBSC) from
industrial residues. HBSC promises eco-friendly building materials with great mechanical performance at earlier ages
than Ordinary Portland Cement (OPC). Preliminary results show the formation of main phase dicalcium silicate (C2S)
and ye’elimite (C4A3$) at 1250oC, as determined by X-ray diffraction (XRD), are promising. The formation of minerals in
the clinker was analyzed by differential scanning calorimetry-thermogravimetry (DSC–TG). Likewise, Scanning electron
microscope (SEM) and XRD were used to carry out the analysis of the micro-structural and hydration products. The main
HBSC hydration products, Ettringite and amorphous Al(OH)3, were formed in the early stages; however, during the later
stages, monosulfate and Strätlingite were formed. Isothermal conduction calorimetry measurements indicate that hydration
properties of the cements are comparable to OPC; the total hydration heat after 3 days was 438 J/g. The optimum compressive
strength values of the mortars after 1-,3-,7-, and 28-days were 24.9 MPa, 33.2 MPa, 35.6MPa and 52.8 MPa which can meet
the requirement of special structures. |
PDF (2.4 MB) |
|