Preparation and Characterization of Lime Activated Unfired Bricks Made with Industrial Wastes

Abstract

Utilization of fly ash can reduces the solid waste disposal problem and minimization of pollution also. Conventional production of bricks usually utilizes clay and shale as the source material and requires high temperature (900– 1000 °C) kiln firing which is energy intensive, adversely affect the landscape, and can release high level of waste materials. Utilization of fly ash for making lime activated bricks not only give the waste utilization but also save earth shale as well as energy consumption and CO2 emission. The present study deals with the utilization of fly ashes for making lime activated fly ash bricks and their different property characterization after a normal water curing method up to 21 days. The crushing strength was observed 2.02, 3.17 and 5.32 MPa for 7, 14 and 21 days curing respectively. On the other hand apparent porosity and water absorption was observed 52, 52 , 50 and 46, 47 and 43% for 7 , 14 and 21 days curing respectively. The SEM-EDAX analysis was observed the initial formation of CASH phase along with free silica particle. But increasing curing time many new phases were observed such as CSH, CAH etc which reduce free silica particles present inside the bricks, responsible for further increase in strength.