Formation behavior of PCDD/Fs during waste pyrolysis and incineration: Effect of temperature, calcium oxide addition, and redox atmosphere

Environ Pollut. 2024 Apr 17:124011. doi: 10.1016/j.envpol.2024.124011. Online ahead of print.ABSTRACTThe clean and efficient utilization of municipal solid waste (MSW) has attracted increasing concerns in recent years. Pyrolysis of MSW is one of the promising options due to the production of high-value intermediates and the inhibition of pollutants at reducing atmosphere. Herein, the formation behavior of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during MSW pyrolysis and incineration was experimentally investigated and compared. The influence of reaction temperature, CaO addition, and redox atmosphere on PCDD/Fs formation were compared and discussed. The results showed as the pyrolysis temperature increased, the mass concentration and international toxicity equivalence quantity of PCDD/Fs initially peaked at ∼750 oC before declining. Most of the generated PCDD/Fs were concentrated in the liquid and gaseous products, accounting for ∼90% of the total. Among liquid products, octachlorodibenzo-p-dioxin (O8CDD), 2,3,4,7,8-pentachlorodibenzofuran and 1,2,3,4,6,7,8-heptachlorodibenzofuran (H7CDF) were the most crucial mass concentration contributors, while in gas products, high-chlorinated PCDD/Fs, such as O8CDD, octachlorodibenzofuran (O8CDF) and 1,2,3,4,6,7,8-H7CDF were predominant. Compared to incineration, the formation of PCDD/Fs was 7-20 times greater than that from pyrolysis. This discrepancy can be attributed to the hydrogen-rich and oxygen-deficient ...
Source: Environmental Pollution - Category: Environmental Health Authors: Source Type: research