Recovery of mineral dust in composite materials

Abstract

This work evaluates the potential of use of mineral dust waste from stone extraction and processing industries to develop composite materials to construction sector. Actually, a high volume of mineral waste was generated, in a stone extraction and processing industries, without any type of recycling and recovery. In this work, this waste was combined with a biopolymeric material, with different mass ratios, namely 70:30 and 50:50 of mineral waste and polymeric material. To accelerate the curing process, a compression moulding process was used. After that, a several characterization tests were performed, in order to compare the main properties of the composite materials obtained with different mass ratios of mineral dust and polymeric material. The physical and mechanical tests were performed to evaluate the density, moisture absorption, flexural strength and flexural modulus. Besides that, the thermal properties were obtained using an Alambeta testing device. The experimental results show a decrease of density of the composite materials from 2.7 g cm-3 to 2.03 g cm-3, compared with virgin slate rock. In terms of mechanical performance, an increase of flexural strength from 17.1 MPa to approximately 80 MPa was verified between Viroc and the composite materials obtained. In addition to this, an HB rating on flammability test guarantees to the composite materials an excellent capacity to fire resistance. These results allow to conclude that the recycling and recovery the slate waste has a big potential of application in several areas, such as construction one.