Characteristics and properties of a mixture containing fly ash, hydrated lime, and an organic additive

Laboratory tests were carried out to obtain the “stabilization” of a fly ashes (FA) from municipal solid waste (MSW) incinerator plant, by addition of hydrated lime (20% w/w). Room-temperature granulation of the mix with different amounts of water, containing a polyaminoalkylolic additive, was carried out in a rotating drum. The presence of the organic additive in the mixes increases the compressive strength of the granules seasoned at the room temperature; moreover, the leachability of the chromium (VI) ion in acid medium (standard test) decreases. Cylindrical specimens were also tested for both mechanical strength and leaching behaviors. The inertization with hydrated lime and organic additive is simpler and less expensive than any other method so far investigated. The FA was characterized by means of X-ray diffraction, thermogravimetry, chemical, and particle-size analyses.