Caracterização cerâmica de matéria-prima com alto teor de matéria orgânica reduzido por compostagem

Abstract

The objective of this work was to analyze the process of processing of a turfous raw material extracted from the Poços de Caldas region, using the composting method to reduce organic matter (OM), in order to use it in ceramic applications. The decrease of OM through compost biomineration is a method never before used for this purpose, arising from the work of the Research Group on Mineral Resources of UNIFAL-MG and characterizing an innovation in the management of mineral resources. The process was divided into two stages. During the first stage, the raw materials used in three different groups were divided, preserving one of the pure samples, adding ammonium sulfate to another and finally adding bovine manure in the third sample, aiming to encourage the activity of MO-degrading microorganisms. The process lasted six months, and at every two months, the amount of MO present in each sample was analyzed by the modified Walkley-Black method (WB). The results obtained during the stipulated period reached a maximum degradation of 58.3 ± 5.7% of MO in bovine manure (TB), 53.9 ± 4.0% of OM in the ammonium sulfate (TN) and 50.7 ± 4.9% of MO in the pure material stack (TP). At the end of the six months, the ceramic characterization of the processed raw material was carried out. For the second step, the raw materials used were divided into two groups, keeping one of the samples pure and adding bovine manure in the second sample. The process lasted four months, and at each month, the amount of MO present in each sample was analyzed again using the WB method. The results obtained were of a maximum degradation of 58.3 ± 5.7% of OM in the bovine waste (TB2) and 50.7 ± 4.9% of OM in the pure material (TP2). The ceramic characterization of the raw material processed was again performed. Throughout the two stages of composting, it was possible to prove that the proposed methodology is functional in the decrease of OM in ceramic raw material. Regarding the compost product, the results were positive, indicating that this material can fit the acceptable characteristics of use in any of the hundreds of existing ceramic applications.