No abstract

Heavy metal and polycyclic aromatic hydrocarbons (PAHs) in flue gas have received considerable attention in recent years due to their mutagenic or carcinogenic properties. The present study is carried out to investigate the influence of the quantity of heavy metals on PAHs formation in fly ash. A fluidized bed incinerator was used in this experiment to obtain fly ash of chemical similarity by incinerating various compositions of waste. The obtained fly ash, both with and without heavy metal, were used to adsorb the PAHs in the flue gas and to investigate the formation of PAHs in fly ash. The results indicate that carbon and heavy metals most greatly influence the formation of PAHs in the fly ash. Carbon is absorptive; heavy metals encourage not only absorption of PAHs but also catalyze PAHs formation.

Previous studies have shown that pollutants from incineration include heavy metal, PAH, PCB, PCDD and PCDF, which pose a threat to human health. It was also shown that most heavy metals were adsorbed on paniculate matter. However, the relations among heavy metals and organic compounds were seldom mentioned. The present study focuses on the relations among particle pollutants, PAH, heavy metals and carbon.The experiments were carried out in a bubbling fluidized bed with two consecutive cyclones, a wet scrubber and an activated carbon scrubber. The feedstocks primarily simulated sawdust, paint, and plastic containers that from the furniture manufacturing process. The results indicated that the influences of heavy metals on PAH formation during the incineration were due to metal catalysis and carbon adsorption.