Results of sludge incineration tests on a demonstrative fluidised bed furna
ce are reported and discussed. They show that particulate, heavy metals and
acidic compounds in the emissions can be easily controlled both when sludg
e is spiked with chlorinated hydrocarbons up to a chlorine concentration in
the feed of 5%, and when the afterburner is switched off. As for organic m
icropollutants, polynuclear aromatic hydrocarbons (PAH) were much lower tha
n the Italian limits of 10 mug/m(3) (no limits are at present considered in
the European Directives). Dioxins (PCDDs) and furans (PCDFs) in some tests
exceeded the limit of 0.1 ng/m(3) (TE) but the concentrations in the fly a
shes were much lower, thus evidencing a possible presence of contaminants i
n gas phase. PAHs and PCDD/PCDFs were not depending on the afterburning ope
ration, the presence of organic chlorine in the feed sludge and the copper
addition to sewage sludge.