Use of DC Plasma Treated Air Pollution Control (APC) Residue Glass as Pozzolanic Additive in Portland Cement

Air pollution control (APC) residues are hazardous waste generated from the air pollution abatement systems operating at energy from waste plants processing municipal solid waste. APC residues can be blended with glass forming additives and treated by direct current (DC) plasma technology, producing a stable, non-hazardous inert glass slag. This research has characterised the pozzolanic activity of this glass slag. The effects of glass cooling rate (quenched or air cooled) and particle size distribution have been investigated. The results show that quenched or fritted APC glass is significantly more pozzolanic than air-cooled glass. The optimum blended Portland cement paste, which maximises APC glass utilization and has the best properties, contained 20 wt % fritted APC glass slag. This blended Portland cement paste had low water demand, developed a dense microstructure and had high compressive strength (~100 MPa). The research has demonstrated that the glass slag resulting from DC plasma treatment of APC residues is pozzolanic and has potential to be beneficially reused in blended cements.