THERMAL-BEHAVIOR OF PAHS, HEXACHLOROBENZENE AND PCDDS PCDFS ADSORBED ON LIGNITE COKE FROM FLUE-GAS CLEANING MUNICIPAL WASTE INCINERATORS/

Lignite coke is increasingly employed as an adsorbent for flue-gas cle aning, for example, in waste incinerators. The aim of the studies desc ribed here was to verify the assumed deposition reliability of moving bed adsorbers even in the case of operational malfunction. To this end , the occurrence of glow clusters in coke beds loaded with various pol lutants such as polyaromatic hydrocarbons (PAHs), hexachlorobenzene (H CB), polychlorinated dibenzodioxins and dibenzofurans (PCDDs, PCDFs) w as simulated and the thermal behavior of adsorbed compounds recorded b y quantitative measurement of the coke pollutant and of the desorption gases. Assuming an incident that would lead to the spontaneous igniti on of the adsorber, the results of our studies show that due to the de sorption or decomposition reactions of PAHs, PCDDs and PCDFs, as well as HCB as a model substance for high-chlorinated compounds, only small fractions of pollutants are released.