Light Weight Plasters Containing Vermiculite and FGD Gypsum Wastes for Sustainable and Energy Efficient Building Construction Material

Abstract

Development of lightweight plasters for mortar rendering utilizing Flue gas desulfurization (FGD) gypsum have been reported here. Lightweight plasters prepared using FGD gypsum and exfoliated vermiculite were characterized and studied in detail for interior wall applications. Different gypsum vermiculite plasters (GVP) with variable amounts of vermiculite were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermal gravimetric analysis (TG-DTG). The physicochemical and mechanical properties of all the samples are determined and considered to be efficient for interior applications. An optimum mix composition was selected based on its compressive strength, water absorption and porosity. Water absorption and porosity studies restrict the usage of GVP only to interior wall purposes. The acoustic performance of the materials revealed good sound absorption (α = 0.65). Plasters exhibit satisfactory durability under severe conditions of winter and summer weather. GVP shows excellent fire resistance under BS 476-1997 fire resistance classification with thermal conductivities (< 0.161 W/mK) much lower than standard building materials, which makes them fit for energy efficient insulation materials. These studies depict the efficient utilization of thermal power plant waste, FGD gypsum in interior wall insulation for mortar rendering and can be further extended to exterior construction applications by reducing water absorption.