Process for vitrifying residues containing heavy metals with a chlorine content of more than 10 by mass and melting furnace for carrying out the process

摘要

Residues (18) with a chlorine content in excess of 10% by mass are converted into a melt (4) in a furnace (1) comprises main and exit sections (2, 5) with overhead heating. In the main section the residue constituents not embeddable into the melt are separated into two fractions (22, 23). The fraction (22) containing easily volatile constituents, in particular, heavy metals is evaporated and removed from the furnace together with the flue gas (14) for subsequent condensing and collection. The fraction (23) in the form of liquid salts with a low heavy metal content is separated and collected from the surface of the melt (4). The furnace is provided with a loading unit (15) for residues (18) and additives (20). In addition to overhead heating it is provided with electrodes (12) in the melt bath (3). The outer wall of the furnace main section (2) has an opening (16) for removal of liquid salts. The lower edge of this opening is 1-10 cm above the melt level determined by the overflow platform (8).