FREMGANGSMAADE TIL FJERNELSE AF TUNGMETALFORBINDELSER FRA FILTERSTOEVET VED AFFALDSFORBRAENDINGSANLAEG OG ROEGGASAFSTOEVNINGS- OG GASRENSNINGSANLAEG

摘要

Heavy metal compounds are removed from the filter dust of industrial plants by thermal separation, by heating of the filter dust in a reaction vessel (4) up to the vaporisation temperature and quenching of the resulting heavy metal vapours in a cooler (13), condensing, subliming and taking off. Carrier gas (9) or circulating gas (16) is used for fluidising the filter dust, or a vacuum pump (32) is used for vaporising the heavy metal compounds under reduced pressure. Additives are used for promoting the vaporisation or conversion of the heavy metals into more volatile compounds. In plants operating continuously or discontinuously, the fine dust is advantageously separated off before the removal of the heavy metals and further treated separately.