Effect of partial replacement with thermally processed sugar cane bagasse on the properties of mortars

Resumo

Sugar cane bagasse is a residue of the sugar-alcohol industry, and its main destination is represented by burning
boilers for power generation. The bagasse cogeneration of power produces a sugar cane bagasse ash
(SCBA) residue that does not have a useful destination. Ashes are commonly studied as pozzolan in Portland
cement production. International Standards indicate the use of pozzolan with up to 50% substitution. In the
present work, we investigate the use of SCBA as an addition in Portland cement. For this purpose, Portland
cement was prepared by substituting cement with 0, 10, 20, and 30% processed SCBA in volume. The ashes
were processed by re-burning and grinding and were then characterized by scanning electron microscopy, Xray
diffraction, laser granulometry, X-ray fluorescence spectrometry, the Chapelle method, and pozollanic
activity. To evaluate the cement with substitution, we used the mortar recommended by NBR 7215. The mechanical
properties of the cements with replacement were analysed through tests of the compressive strength
and flexural strength of mortars. The results appear interesting and support the possible use of SCBA in the
production of cement from the aspect of mechanical properties evaluated.