Jm. Hernandez et al., Use of wastes of the sugar industry as pozzolana in lime-pozzolana binders: Study of the reaction, CEM CONCR R, 28(11), 1998, pp. 1525-1536
Mineralogical studies of different wastes of the sugar industry, mainly sug
ar cane bagasse ash and sugar cane straw ash, have shown that such by-produ
cts are likely to be pozzolanic. Their use in lime-pozzolana binders could
become an interesting alternative for developing countries. This paper pres
ents a study that was aimed at monitoring the reaction between lime and was
tes of the sugar industry having pozzolanic properties by evaluating 1) con
tent of calcium hydroxide, dependent on time; 2) development of the pore st
ructure, dependent on time; 3) study of the reaction products at different
stages; and 4) mechanical properties of hardened pastes. The presence of ca
lcium hydroxide was confirmed by x-ray diffraction analysis and thermogravi
metic analysis of powder from samples of hydrated lime-pozzolana pastes. Th
e reaction products in hydrated pastes were observed in a scanning electron
microscope, and the pore structure was assessed using a mercury intrusion
porosimeter: The results of the study show that sugar cane bagasse ash does
not act like a reactive pozzolana, mainly due to the presence of unburned
material and carbon, whereas sugar cane straw ash shows good gozzolanic act
ivity comparable to that of rice husk ash. (C) 1998 Elsevier Science Ltd.