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Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) and heavy metals emitted from hazardous waste incinerators have aroused public concern due to the risks to the environment and human health. In the study, phase distribution, migration, and relationship of PCDD/F and heavy metals (arsenic, cadmium, chromium, copper, mercury, nickel, plumbum, zinc) are investigated in a typical hazardous waste incinerator. The PCDD/F mass concentrations and toxic equivalent quantity are reduced to 3.26 ng/Nm3 and 0.0484 ng/Nm3 by air control pollution devices, with 93.1% remove efficiency. High sulfur content in hazardous waste results in low PCDD/F and heavy metals emissions. Moreover, migration analysis of PCDD/F mass concentrations indicates that vast PCDD/F migrates to the mixtures with sodium bicarbonate and activated carbon (52.4%), followed by fly ash (21.8%), sodium hydroxide solution (19.3%), and atmosphere (6.49%). Furthermore, TCDF isomers (37%) dominate among the PCDD/F congeners, while 1,2,3,4,6,7,8-HpCDF (20%) dominates among 2,3,7,8-substituted congeners. Deduced by the ratio of PCDF/PCDD, the dominant mechanism of PCDD/F is de novo synthesis and chlorobenzene route synthesis. Based on the relative enrichment index, heavy metals are classified into three types: volatile heavy metals (plumbum, zinc, cadmium, mercury), medium volatile heavy metals (copper, chromium, arsenic), involatile heavy metals (nickel). Additionally, copper is inclined to deposit into the bottom slag as CuSO 4 rather than the volatile substance due to high levels of sulfur dioxide (3000 parts per million). The migration behavior of heavy metals is dependent on the volatility properties of these metals. Statistically, PCDD/F emissions have the highest correlation coefficient with plumbum (r = 0.815), followed by nickel (r = −0.798). Besides, the PCDD/F formation is promoted by the volatile heavy metal, prevented by medium volatile heavy metals. The study not only provides a comprehensive understanding of PCDD/F and heavy metals characteristics but also effective and feasible strategies to reduce the toxic pollutants emissions in large-scale hazardous waste incinerators. [Display omitted] • Phase profiles of dioxin along air pollution control devices are revealed. • High sulfur content in hazardous waste results in low emissions. • The most (52.4%) dioxin emissions migrate to active carbon & bicarb. • The migration behavior of heavy metals is dependent on the volatility properties. • The dioxin formation is promoted by the volatile heavy metals. [ABSTRACT FROM AUTHOR]

Ten years ago, Spain was hit by a severe economic crisis (2009–2013), while the economy recovered in 2014. In the present study, the source changes of PM 10 from pre- and post-economic crisis to economic recovery were investigated using receptor model (Positive Matrix Factorization: PMF). PM 10 samples were collected during 2014 at six different sites in Andalusia, located in the southern Spain (1–7° W, 37–39° N). Seven source factors were identified as soil dust (17.9–34.8%), road traffic (12.2–25.9%), industrial emission (1.2–16.6%), oil combustion (0–16.1%), sea salt (5.0–15.7%), secondary nitrate (<0.05–30.4%) and secondary sulfate (4.4–15.1%). The soil dust source had the greatest influence on these six stations, followed by the road traffic source. The area was seriously affected by industrial pollution, even to the suburban and rural areas. Industry source contribution showed an increase trend from financial crisis periods to economic recovery, and the contribution in 2014 was even higher than pre-crisis level. As a result, the concentrations of heavy metals (Zn, Cu, Pb, Cr and Ni) in the atmosphere were significant increased, thus enhanced their toxicity and health risks for people. The economic recovery after the financial crisis in Spain may be at the expense of emission control targets and air pollution. Image 1 • This work studied the particulate matter compositions and sources in Spain. • Seven source factors were identified by Positive Matrix Factorization model. • Soil dust had the greatest influence in study area, followed by road traffic source. • Industry contribution showed an increase trend from financial crisis to recovery. • Increased industry source resulted to the increases of the atmospheric heavy metals. [ABSTRACT FROM AUTHOR]