A review on the formation and remediations of polychlorinated dibenzo p-dioxins and dibenzo-furans (PCDD/Fs) during thermal processes with a focus on MSW process

Abstract

Polychlorinated dibenzo-p-dioxins and dibenzo-furans (PCDD/Fs) are notorious pollutants classified as persistent organic pollutants (POPs), which even at trace levels can bio-accumulate in the environment and have negative effects on organisms. Due to their adverse health effects, countries around the globe have introduced stringent emission standards to reduce the formation of PCDD/Fs. Using data in the literature over the past two decades (2001 to 2023), this review discussed the PCDD/F emissions from incineration facilities, E-waste recycling, iron sintering, secondary metal smelting plants, and crematories. But the review only focused on pollutants and remediation strategies from the incineration processes. There are two heterogeneous mechanism pathways that lead to the formation of PCDD/Fs, firstly, the De novo phase, using macromolecules of carbon or polycyclic aromatic hydrocarbons to begin the synthesis, and secondly, the condensation reaction beginning with the rearrangement of the molecular structure of the precursor compound. On the remediation strategies, adsorption injections were the most preferred method; however, recent studies reported other strategies such as catalytic filtration systems, an electron beam system, and good combustion practices. This review concluded that a lot has been done to manage and prevent PCDD/F formation efficiently to the level which no longer poses a hazard to human health and the environment. Graphical abstract

State-of-the-Art and Recent Advances in the Abatement of Gaseous Pollutants from Waste-to-Energy

“…In the energy recovery section of the process, the reformation of undesired by-products (PCDD/Fs in particular) must be prevented. Reducing the residence time of dust-laden gas in the 450 • C to 200 • C temperature zone reduces the risk of the formation of PCDD/Fs and similar compounds [51]. The potential for PCDD/F production is increased by dust removal devices (such as electrostatic precipitators and bag filters) operating at temperatures higher than 200 • C in high dust zones.…”

Health benefits and health risks of contaminated fish consumption: Current research outputs, research approaches, and perspectives

“…Dioxins are highly toxic chemicals that can be present in the fatty tissues of some fish species [ 85 ]. These compounds are formed as byproducts of industrial processes such as waste incineration and chemical manufacturing [ 94 ]. They are persistent in the environment and can accumulate in the food chain, posing a risk to human health.…”

Optimizing the Elimination of Dioxin-Like Compounds (PCDD/Fs and PCBs) Through Effective Combustion Practices in the Flue Gas in the Medical Waste Incineration Facility

“…PCDD/Fs and dioxin like polychlorinated biphenyl (dl-PCBs) are known contaminants belonging to the group of compounds classified as Persistent Organic Pollutants (POPs). PCDD/Fs compounds are created in all processes associated with the combustion of organics within the presence of different chlorine compounds (modern and domestic coal burning, waste incinerators, sinter plants, cement industry, ferrous and non-ferrous metallurgy, engine transport) [2][3][4]. Due to their lipophilic nature, they are known to bio accumulate, are carcinogenic and pose a significant health risk even at low concentrations [5].…”