Geopolímero produzido com dois diferentes resíduos: lodo de ETA como precursor e areia de vidro como agregado

Abstract

Aiming to mitigate environmental impacts, this study proposed the production of geopolymers, a type of ceramic material that can be developed at room temperature through alkaline activation, as an alternative management solution for the sludge generated at the Water Treatment Plant (WTP) in Macapá, Amapá, Brazil. In the production of geopolymers, it is possible to use a variety of waste materials as raw materials, provided they are composed of aluminum (Al), silicon (Si), and/or potassium (K), for example. In this work, in addition to using WTP sludge as the main raw material, we sought to verify whether it would be technically feasible to use sand from ground glass as an aggregate, thus replacing the natural aggregate - river sand. In this sense, two different geopolymers were produced, both using WTP sludge as a precursor, but with two different aggregates: river sand and ground glass sand. The processing of the materials involved the stages of drying, grinding, sieving, and calcination. Geopolymer test specimens were then molded and evaluated for compressive strength and microstructure. The results prove that it is technically feasible to produce geopolymers using WTP sludge as a precursor and glass sand as an aggregate, since when subjected to mechanical strength testing, this material presented an average strength of 16 MPa after 28 days, making it suitable for various uses in the construction industry. In addition, its microstructure proved to be cohesive and homogeneous. In this context, it was found that it is possible to produce new ceramic materials using ETA sludge as a precursor and ground glass sand as an aggregate. This is, therefore, a sustainable alternative for waste management, promoting the conservation of natural resources and reducing the environmental impact of civil construction.