SUSTAINABLE SOLUTIONS FOR MANAGING ENVIRONMENTALLY HAZARDOUS WASTE MATERIALS: REAPPLICATION OF FLY ASH

Abstract

The disposal of the fly ash may pose a significant risk to the environment due to the possible leaching of hazardous pollutants. The only sustainable economic solution for the pollution-prevention of theenvironment is the reuse of fly ash in building materials. Some of building composites, in which fly ash iscombined with refractory components can withstand high temperatures. In this investigation testing composites were based on fly ash mixed with high-aluminate cement. Investigated fly ashes were previously subjected to mechano-activation. The leaching behavior and potential environmental impact of hazardous elements were analyzed. Mineral phase analysis by means of XRD was accented due to the fly ash high dependence on its origin. Crystalline phases were investigated by means of DTA. Scanning electron microscopy was used in microstructure analysis. The leachability of toxic elements was within allowedrange, thus investigated fly ashes can be replicated in building materials. Investigated fly ash-cement composites proved to have high physico-mechanical performances, but also good thermo-insulationcharacteristics. The overall results showed that application of the fly ash in building composites unsustainable solution for managing this environmentally hazardous waste material. Key words:fly ash, thermo-insulation, toxic elements, reapplication, building composites.