Title: Immobilization of Wastes by Metakaolin-Blended Cements

Author(s): J. Pera, E. Bonnin and M. Chabannet

Publication: Symposium Paper

Volume: 178

Issue:

Appears on pages(s): 997-1006

Keywords: blended cement; fly ash; latex; leaching; metakaolin; mortar.

DOI: 10.14359/6019

Date: 6/1/1998

Abstract:
Metakaolin-blended cements were used to stabilize two kinds of wastes: municipal incinerator fly ash and latex waste coming from the carpet industry. The physical and chemical properties of wastes were investigated and mortars containing these wastes were cast. A blended cement containing 20 % metakaolin was utilized to immobilize the incinerator fly ash which was introduced as a sand substitute in mortars. Leaching tests and microstructural investigations were carried out as well as mechanical tests. The results obtained show that metakaolin plays a beneficial effect in the stabilization of chlorides contained in such fly ash. Cements containing from 10 to 30 % metakaolin were used to cast mortars, in which latex was introduced as a sand substitute. Metakaolin reacted with the calcite contained in the latex and the C3A of portland cement to form carboaluminate. Leaching tests showed a good immobilization of this waste.