Mortar produced with sulphur slime aggregate

Abstract

It is known that the use of various industrial wastes as recycled aggregate for concrete to build environmentally sustainable structures has several practical and economic advantages. Usually such recycled aggregates consist mainly of crushed concrete and crushed asphalt pavement material. However, in this study a by-product of acid – sulphur slime is used as a partial substitute for natural fine aggregate (sand). Sulphur slime is a solid material consisting mainly of elemental orthorombic sulphur with some impurities like gypsum and anhydrite. The goal of this research is to investigate whether it is possible to manufacture concrete with sulphur slime despite the presence of elemental sulphur. Each set of samples analyzed was based on 5 different compositions with 0 %, 10 %, 20 %, 30 %, 40% Sulphur slime as a substitute of aggregate. Samples was tested for their mechanical characteristics including the compressive and flexural strength. The samples structure was analyzed with SEM and optical microscopy and the composition of the materials was analyzed through SEM and XRD. The inclusion of Sulphur slime led to a reduction in the mechanical properties of the material, related to the formation of secondary ettringite and associated expansion within the material.