Characterization of sludge from the Water Treatment Plant (WTP) of the city of Palmeira dos Índios - Alagoas for potential application in ceramic masses

ABSTRACT

The sludge from Water Treatment Plants (WTP) when disposed of improperly can cause environmental imbalance and public health problems due to leaching of heavy metals into water bodies. Therefore, this work aimed to characterize the physical, chemical, thermal and mineralogical characteristics of the sludge from the WTP of the city of Palmeira dos Índios-AL. The methodology used was experimental, through the performance of granulometry tests, Atterberg limits, X-ray fluorescence, X-ray diffraction and thermogravimetric analysis. After the granulometry test, the sludge presented characteristics of fine sand. The chemical analysis identified the presence of Ca (7.81%) and Mg (2.51%), which may interact with glass phase forming elements Si (55.65%) and Al (12.03%) during sintering. Furthermore, the most significant percentages of silicon and aluminum were in the form of quartz and kaolinite, corroborating the X-ray fluorescence results. In the thermal analysis there was a loss of mass around 42% until the temperature of 400°C, indicating the possibility of thermally treating the by-product before its incorporation into ceramics. Finally, the sludge presents potential for application in ceramic matrices, given the presence of elements with melting characteristics.

Keywords
By-products; Physical-chemical characterization; Melting Elements; Circular Economy