Technological behaviour and leaching tests in ceramic tile bodies obtained by recycling of copper slag and MSW fly ash wastes

Abstract

The substitution of standard clays to residues, in this case copper smelter slag and fly ashes coming from the incineration process of MSW in traditional ceramics manufacturing, could suppose cost savings due to the use of recycling by-products as raw materials and reduce firing temperatures. However, these residues are considered a factor of air, soil and water contamination when its stabilization is not viable. The aim of this paper is to evaluate the feasibility of adding this residue in manufacturing of ceramic bricks, as well as tested the immobilization of Pb and As in ceramic tile bodies obtained. Water absorption, linear contraction, and bending strength have been accomplished. The decrease in water absorption with the increase of waste added was tested. The incorporation of these wastes gives rise to an increase in strength. The results showed the viability of replacing up to 40% of clay with these residues, with an improvement in the resistance of pieces compared to ceramics made without adding residues. The immobilization of As and Pb was also observed in the ceramic bodies obtained. Leaching tests show that immobilization of both elements (As and Pb) improves with increasing firing temperature.