Environmental impact of industrial plants combustion processes: kinetic and formation/destruction mechanisms of PolichlorinatedDibenzo-p-Dioxins and PolichlorinatedDibenzoFurans

The aim of the project was to study the mechanism of formation and degradation of PolyChlorinatedDibenzo-p-Dioxins (PCDDs) and PolyChlorinatedDibenzoFurans (PCDFs) in combustion processes. Today the challenge is to demonstrate that the conclusion based on laboratory scale experiments and the models coming from the results are useful tools to estimate emissions and to prevent or reduce PCDD/F (sum of PCDDs and PCDFs) formation in the flue gas cleaning system of plants. Following this, the study was developed at two different scales: Laboratory scale. The native carbon oxidation and PCDD/F formation were simultaneously studied at different temperatures (230-350 °C) and times (0-1440 min) in order to establish a direct correlation between the disappearance of the reagents and the formation of the products. The kinetic runs were conducted in a experimental set up where conditions were chosen to gain information on the role of fly ash deposits in cold zone of the plant in PCCD/F formation reaction Real plant scale. An extensive experimental study of a secondary aluminium casting plant flue gas cleaning system was performed. In particular, on the strength of the knowledge obtained by laboratory studies and the results of the samplings, the best strategies to prevent PCDD/F formation were identify and Air Pollution Control Device (APCD) performance was improved.