Prevention of electrofilter ash toxic leaching by embedding in composite materials

Abstract

Disposal of the fly ash may pose a significant risk to the environment due to the leaching of hazardous pollutants. The only sustainable solution for the pollution-prevention is the reapplication of fly ash as one of the components in construction material composites. There is a risk of leaching even when fly ash is built-in the construction composites and the goal of this investigation was to prove that leaching concentrations of toxic elements is in range assigned by actual regulations. Fly ash was applied in several composits: mortar, concrete and asphalt. The leachability of the potentially toxic elements from the fly ash based products was investigated. The leaching behavior and potential environmental impact of the 11 potentially hazardous elements was tracked: Pb, Cd, Zn, Cu, Ni, Cr, Hg, As, Ba, Sb and Se. A detailed study of physico-chemical characteristics of the fly ash is included. The overall results showed that most of the elements are more readily leachable from the fly ash in comparison with the fly ash based composites.