Physicochemical and Mineralogical Analysis of Steel-Slag Blended Cements

2018

English

The dominant role of ordinary Portland cement is slowly decreasing in the construction industry in favor of substituted or composite cements. This is due to the added advantage or benefits of blended cements such as durability, cost and environmental friendliness. Steel slag, an industrial waste in the manufacture of steel and a major mineral admixture in Europe is not well utilized in Ghana because no extensive scientific research has been conducted into its alternate use. Meanwhile an estimated 5,000 tons of steel slag is dumped as waste every year for the past 20 years and it is gradually becoming an environmental challenge. This work has studied the alternate use of steel slag from Wahome Steel Works, a steel manufacturing company in Ghana, as a mineral admixture in Portland cement for construction applications. The physical properties of the slag such as specific gravity, Blaine indices and particle size distribution were studied. The chemical and mineralogical (XRF, XRD and SEM) analysis revealed that the slag is chemically suitable and contained the relevant minerals and phases. The slag-cement mixture required less water to form a workable paste and increased in setting time as slag content increased in the mix. The results also revealed that, water permeability decreased with increasing slag content.The slag-cement mix recorded lower compressive strengths at early ages but appreciated in strength at later ages, recording strength of 48.9 MPa at 30% replacement.

Boakye, K. A.; Atiemo, E.; Tagbor, T. A.; Adjaottor, A. A.; Adjei, D.