Maximization of the use of casting sand residue in the production of fired ceramic bricks

In this study, a red ceramic was developed with the addition of sand residue from deburring and finishing processing of cast iron molds, replacing a variable fraction of the clay. The formulated masses were shaped by pressing and firing at different temperatures (850, 900 and 1000 deg C) at a heating rate of 180 deg C/h and 2-hour level. The bodies were characterized for their density prior to firing, and after firing, for mechanical strength, linear retraction, water absorption and porosity. From these results, tests were carried out with the purpose of evaluating the possible release of pollutants from the ceramic pieces produced by leaching tests according to Brazilian standards. The use of smelting sand residue, a low plasticity component, has been shown to be feasible with a few adjustments in the processing parameters and environmentally safe, as demonstrated by the experimental results. (author)