Water treatment sludge as supplementary cementitious materials in Portland cement

Reference	Presenter	Authors (Institution)	Abstract
04-068	Caroline Angulski da Luz	Alexandre, E.(UTFPR); da Luz, C.A.(UTFPR); Schuster, G.C.(UTFPR); Vicentin, B.(UTFPR); Jacobsen, S.(UTFPR);	In Brazil, water treatment sludge (WTS) is discarded into watercourses, or when it is treated to increase the solids content, the residue is landfilled. The chemical composition of WTS is basically Al2O3, SiO2 and Fe2O3 which are also present in Portland cement. In this context, this paper investigated to use of WTS as supplementary cementitious materials (SCM) in Portland cement type V (according to brazilian standard) in 20%. Pastes were made using a water/cement of 0.4 and the compressive strength, heat of hydration and microstructure analyses (MEV, XRD and TGA) were analyzed. The results showed that WTS caused a delay in hydration reactions implying a lower compressive strength and lower formation of products of hydration at 7 days. However, at 28 days, the behavior was similar than those observed by the reference (without WTS) and reached 34 MPa. The results showed that WTS could be a potential SCM for Portland cement allowing its safe disposal.
<< Back