EVALUATION OF THE ELEMENTAL COMPOSITION OF MUNICIPAL SOLID WASTE BOTTOM ASH: A NEW METHODOLOGY FOR SAMPLE PREPARATION

The disposal of municipal solid waste (MSW) to thermochemical treatments promotes the formation of ashes as a by-product, which constitutes an important role in the design and operation of energy recovery plants, as the ash can cause corrosion and fouling problems. In this sense, this work analyzed samples of bottom ashes from combustible fractions (organic matter, plastics, textiles, paper/cardboard/Tetra Pak® and sanitary waste) of MSW in natura from Santo Andre – SP, Brazil. For this, a new methodology for sample preparation was proposed to evaluate the elemental composition of the bottom ashes, for later analysis by Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDS). The obtained data showed a standard deviation of less than 10%, guaranteeing a greater reliability of the results and corroborating with standard deviations presented in the scientific literature. In addition, the elemental composition of the bottom ash was similar between the different combustible fractions evaluated. Keywords: MSW, Combustible fractions, SEM-EDS.