Influence of the procedure for granulometric sample adjustment of red ceramic aggregated with dimension stone wastes for classification according to the SBNT criteria's

In order to clarify questions about the granulometric preparation of samples for the classification of solid wastes according to the Brazilian technical standard (NBR 10004/04), solubilization tests were carried out on red ceramic specimens made with conventional clay aggregated with ornamental rock residues. Samples were prepared by fragmentation and milling to verify the effects on metals releasing to the extractor medium. The specimens were made with 80% clay, 20% residue and 10% (m/m) moisture and sintered at 1000 °C. The data show that ceramics made with conventional clay, when discarded, will produce non inert wastes, as well as the ceramics made with dimension stone wastes added to the conventional raw material, according to the granulometry of its particles. After all, the metals concentration in the solubilization test are influenced by the sample granulometry. This paper shows that the method of granulometric adjustment should be detailed in the technical standard for solubilization tests (NBR 10006/04), in order to ensure the reliability of the method for classification of solid wastes. (author)