International Conference on Energy, Water and Environmental Science & Technology

Inorganic polymers, more commonly referred to as geopolymers , are alumino- silicate materials which have desirable physical and chemical properties as a binder, for a diverse range of potential applications, including: construction & infrastructure industries, immobilisation of toxic, hazardous and radioactive wastes and fire resistant composites, with a much smaller Carbon footprint than traditional Portland cements. In this paper, chemical activation of binder made from industrial by-products viz., fly ash and Ground Granulated Blast Furnace Slag (GGBS) by geopolymerisa tion is discussed. The influences of the concentration of activator (made from mixing sodium hydroxide and sodium silicate solutions) and activator to binder ratio (A/B) on performance characteristics and micro structure of binder are reported. Based on the experimental studies, the optimum Si/Al ratio is found to be 0.50 with maximum strength of binder system of 25 % Fly ash + 75% GGBS cured at room temperature being65MPa. Applications of Geoplymer technology in the brick production have been made with the optimized mix proportions. The mechanical strength of paver blocks tested and it was found that Geopolymer blocks containing (25% Fly ash +75% GGBS) with A/B ratio of 0.7 possessed relatively high compressive strength of 35MPawhich is much above the desired compressive strength in a building block. The micrographs and the XRD patterns provide an insight into the product morphology of geopolymers. The lower carbon footprint of Geopolymeric composition in comparison with Portland-based cement is quantified in this paper and hence, the application of Geopolymer technology substantially reduces the green house gas emission of the construction industry.