Process for the disposal of flue gas residues

Abstract

Solid residues obtained in flue gas purification, in particular flue dusts, are disposed in an environmentally compatible and economical manner by acid extracting heavy metals from the residues, precipitating the heavy metals from the extract, separating the precipitate from the mother liquor, subjecting the precipitate containing heavy metals to mechanical stress during which procedure the water contained in the precipitate is released and the precipitate itself is resuspended, and then adding a hydraulic binder to the resuspended precipitate containing heavy metals and/or to the extracted residues separately from one another. The binder-containing mixture can be used to form moldings which, after hardening, are employed for the erection of boundary walls in a landfill, Additionally or alternatively, the plastic binder-containing mixture can be introduced in the form of layers into preformed landfill spaces, where it then hardens.