Potential pathway for reusing Paper Mill Sludge Ash as a Supplementary Material in Alkali-Activated Bricks

Abstract

Abstract Alkali-activated bricks are considered a sustainable alternative in masonry construction. These bricks are produced by reacting the waste materials in an alkaline environment using alkali activators such as sodium silicate and sodium hydroxide. In this study, our objective is to explore the viability of manufacturing alkali-activated bricks using industrial waste materials, specifically by fly Ash, Paper Mill Sludge Ash (PMSA), and Crusher Sand Dust (CSD). To reduce the reliance on fly ash, alkali-activated bricks are manufactured by substituting PMSA in two different melds. The first meld is performed to optimize the PMSA and the second meld is carried out to optimize the Crusher Sand Dust (CSD) as filler material. Meld 3 is used to investigate the impact of the NaOH molarity of the bricks ranging from 6 M to 14 M for the optimum proportions obtained from Melds 1 and 2. XRD, FT-IR, TGA, and SEM analyses were carried out to understand the mineralogical and chemical characterization of the raw materials and brick specimens. Furthermore, various tests were conducted on the bricks to assess their physio-mechanical properties, following the relevant standards outlined in IS requirements. Overall, this study demonstrates the feasibility of producing alkali-activated bricks by utilizing industrial waste materials. These findings offer promising prospects for creating sustainable construction materials while effectively addressing the issue of waste disposal.