PROCESSING AND CHARACTERIZATION OF FINE AGGREGATE OF MUSSEL SHELLS

Abstract

Mariculture industry has been growing in the coastal regions of Brazil, including in Jurujuba beach - Niterói (RJ), and consequently a generation of mussel shell residues, causing an environmental problem. Aiming at a possibility of destination for the residue produced in Niterói, this work intended process the mussel shells to transform in a fine aggregate and characterize it to verify its viability of use. Processing consisted of cleaning, drying, washing in concrete mixer for 4 cycles, re-drying and grinding of material. After processing the material properties was characterized by physical tests of granulometry, density and water absorption; chemical properties as chemical composition, loss of ignition, mineralogical composition and thermogravimetric analysis; and morphological analysis by scanning electron microscopy. The fine aggregate produced had granulometry in optimum zone, according NBR 7211:2009, density of 2.64 g / cm³ and water absorption of 3.23%. The material is composed about 90% calcium carbonate in a crystalline arrangement of aragonite and calcite. The morphology of the grains was predominantly angular, with some porosity, cracks and rough surface texture. From the obtained results it can be concluded that the material produced from mussel shell fulfilling the normative requirements to be used as fine aggregate in the civil construction.