Evaluation by XRD analysis of the influence of grinding process in the pozolanic activity of sugar cane bagasse ash

ABSTRACT The recovery and utilization of residues in cement-based matrices, aiming a suitable destination, are increasing because they have pozzolanic properties, so these materials may reduce the consumption of Portland cement. In this paper, it was produced ashes by processing (grinding) sugar cane bagasse ash (SCBA) from a mill located in the state of Pernambuco. The ashes were submitted to a prior process of drying in a drying oven and sieving for the removal of contaminating materials (leaves, stones and others), this material was named CAN. The remaining material was divided into four fractions and each of them was submitted to a burning temperature: 300°C, 400°C, 500°C and 600°C. In order to produce samples, it was adopted a sieving procedure composed by a set of sieves with 200 and 400 mm mesh openings, and grinding in the ball mill for seven hours. As a result, it was obtained four levels of fineness: CAN#200, CAN#400, CANP400 and CANM7H. The samples were characterized by X-ray fluorescence spectrometry, X-ray diffraction, true specific gravity by gas pycnometry and specific surface area by the Blaine method. The SAI of samples with SCBA presented satisfactory results only for the ashes ground for 7 hours. The grinding presented fundamental importance for increasing pozzolanic potential of SCBA.