Caracterização e avaliação da atividade pozolônica da cinzas de biomassa residual de fornos da industria de cerâmica de Crateús

Abstract

Brazil is among the countries with the largest number of ceramic companies in the world, occupying 3rd place in the world ranking. The production of blocks for masonry, roof tiles and other red ceramics goes through input transformation processes, which, after being transformed into the final product, generate a significant amount of waste that often does not have a specific destination, being accumulated in heaps in industries. Among the waste generated, there are remains of damaged blocks and ash resulting from the burning of firewood for the production of ceramics. For some years, supplementary cementitious materials have been studied due to environmental concerns about the amount of cement used in the world, since its production emits carbon dioxide (CO2) into the atmosphere. However, there are still few studies focused on the implementation of biomass ash in concrete and mortar. Therefore, the aim of this study is to characterize and evaluate the pozzolanic activity of residual ash from kilns in the ceramic industry in Crateús-CE. For this, samples of the ash resulting from the burning of dry wood in the region (mofumbo and jurema) were collected and sieved through a 200 sieve with an opening of 75 μm. dispersive) and pozzolanic potential (Determination of the performance index with Portland cement at 28 days and Determination of pozzolanic activity with lime at 7 days). In view of the results obtained, the ash showed a high concentration of calcium in its composition (86.23%) and a sum of SiO2, Al2O3 and Fe2O3 contents of 2.34%. In addition, it showed a decrease in the mortar resistance value of approximately 25%. Although the ash did not show the characteristics of a pozzolanic material, its use may be considered in future studies regarding alkaline activation, given its high concentration of calcium.