Pastas álcali-ativadas à base de cinza de biomassa

Abstract

The growing demand for sustainable alternatives in civil construction drives the development of cementitious materials that are less impactful on the environment. In this context, alkalineactivated materials emerge as a promising option, allowing the partial replacement of Portland cement with industrial waste, such as biomass ash and fly ash. This work investigates the use of biomass ash from the ceramic industry (CBIC) and the cellulose industry (CBC), together with fly ash (CV), in the production of alkaline activated cement pastes. Mini Slump, Setting Time, Resistance, Water Absorption and Scanning Electron Microscopy (SEM) tests were carried out. CBIC, with a high calcium content (86.23%), showed greater reactivity and better mechanical performance in pastes, while CBC, with a high silica content (65.9%) and low calcium content (6.54% ), showed very variable results, with good resistance indices and poor workability indices. The results indicate that these ashes are viable alternatives to Portland cement, contributing to sustainability and the circular economy by reusing industrial waste. However, variability in ash properties requires rigorous control to ensure consistency and optimization of composites. It is concluded that, despite the potential, more studies are needed to expand the application of these solutions on a large scale.