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Pre-dried sewage sludge with high sulfur content was combusted in an electrically heated lab-scale fluidized-bed incinerator. The emission characteristics of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polycyclic aromatic hydrocarbons (PAHs) were studied. Coal and calcium oxide (CaO) were added during part of the sewage sludge combustion tests, in order to optimize combustion conditions and control SO_2 emission. The results indicate that the flue gases emitted during mono-combustion of sewage sludge were characterized by relatively high concentrations of SO_2, NOx and organic pollutants, due to the high sulfur, nitrogen, and volatile matter content of sewage sludge. The total 16 USEPA priority PAHs and 2,3,7,8-substituted PCDD/Fs produced from sewage sludge combustion were found, respectively, to be 106.14 μg/m~3 and 8955.93 pg/m~3 in the flue gas. In the case of co-combustion with coal (m_(sludge)/m_(coal) = 1:1), the 16 PAHs and 2,3,7,8-substituted PCDD/Fs concentrations were markedly lower than those found during mono-combustion of sewage sludge. During co-combustion, a suppressant effect of CaO on PCDD/Fs formation was observed.