Analysis of the Properties in the Hardened State of an Alkali Activated Paste of Metakaolin and Flue Gas Desulfurization (FGD) Residue

Abstract

Alkali activated materials (AAMs) have been studied as an alternative to replace the high demand for common ordinary Portland cement (OPC) in civil construction, with the use of industrial by-products in order to reduce and recycle waste instead of disposal in landfills. The aim of the research is to analyze the properties in the hardened state of an alkali activated paste of metakaolin (MK) and residue from flue gas desulfurization (FGD). Samples of AAMs, with dosages of 100% MK and 0% FGD, 90% MK and 10% FGD, and 80% MK and 20% FGD, were produced with a thermal cure of 6 days at 65 °C in the oven. Subsequently, the specimens were submitted to compressive strength tests, apparent density in the hardened state, water absorption, and void ratio at 7 and 28 days.KeywordsAlkali activated materialsPasteMetakaolinFGD