An eco‐friendly permeable brick with excellent permeability and high strength derived from steel slag wastes

Abstract

AbstractUtilisation of industrial solid wastes to prepare products with high added value is an effective way that could relieve environmental pollution and create huge economic benefits. In this work, steel slag based permeable brick (SSPB) was successfully prepared by liquid phase sintering. The BSE‐EDS results indicate that the microstructure of the SSPB becomes dense because of the formation of a small amount of glass‐liquid phase (Na‐K‐Ca‐Fe‐Si‐O glass system). The effect of sintering temperature on various properties of the SSPB was systematically studied. It is found that as the sintering temperature increases from 1210 to 1300°C, the permeability deceases gradually, as well as the apparent porosity, water retention and water absorption. In contrast, the bulk density and mechanical strengths show gradually increasing trends. Most important of all, the SSPB sintered at 1270°C for 1 hour shows an excellent permeability (5.70 × 10−2 cm/s) and high mechanical strengths (compressive strength, 36.6 MPa; bending strength, 6.8 MPa). The prepared SSPB is not only likely to be a new type of permeable brick for sidewalk construction, but also relieve greatly environmental pollution from steel slag because of the high utilisation rate of steel slag (as high as 90%).