Particulate PCDD/F size distribution and potential deposition in respiratory system from a hazardous waste thermal treatment process

Sheng-Lun Lin; Wei Tang; Jhong-Lin Wu; Yen-Yi Lee; Chih-Lung Wang; Wei-Hsin Chen

doi:10.1016/j.envres.2022.113806

Particulate PCDD/F size distribution and potential deposition in respiratory system from a hazardous waste thermal treatment process

Environ Res. 2022 Nov;214(Pt 2):113806. doi: 10.1016/j.envres.2022.113806. Epub 2022 Jul 19.

Authors

Sheng-Lun Lin¹, Wei Tang¹, Jhong-Lin Wu², Yen-Yi Lee³, Chih-Lung Wang⁴, Wei-Hsin Chen⁵

Affiliations

¹ School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, China.
² Environmental Resource and Management Research Center, National Cheng Kung University, Tainan, 70101, Taiwan.
³ Center for Environmental Toxin and Emerging-contaminant Research, Cheng Shiu University, Kaohsiung, 83347, Taiwan; Department of Food and Beverage Management, Cheng Shiu University, Kaohsiung, 83347, Taiwan.
⁴ Center for Environmental Toxin and Emerging-contaminant Research, Cheng Shiu University, Kaohsiung, 83347, Taiwan; Department of Civil Engineering and Geomatics, Cheng Shiu University, Kaohsiung, 83347, Taiwan.
⁵ Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan, 70101, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung, 407224, Taiwan; Department of Mechanical Engineering, National Chin-Yi University of Technology, Taichung, 411030, Taiwan. Electronic address: weihsinchen@gmail.com.

PMID: 35863447
DOI: 10.1016/j.envres.2022.113806

Abstract

The particulate polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) of various sizes produced from the waste incinerators might have different toxicities, deposition characteristics, and potential health effects in the respiratory system, and their total toxicity equivalent (TEQ) concentration has been strictly regulated in recent years. There is a knowledge gap on the effects of air pollution control devices on particle size distributions (PSDs) of PCDD/Fs and their TEQ deposition. A hazardous waste thermal treatment plant equipped with an advanced scrubber, a cyclone demister, and activated carbon adsorption coupled with a baghouse filtration was investigated in this study. An 8-stage impactor was used to collect the particle distribution of PM₁₀ and bounded PCDD/Fs from the gas stream at four sampling points located before and after each control unit. A "TEQ_DE" index is defined for the toxicity deposition of PM₁₀-PCDD/F in the respiratory system. The advanced scrubbers significantly reduced the PM₁₀-PCDD/F levels, especially for those with sizes ≥0.6 and ≤ 0.4 μm. Additionally, the cyclone also showed a better performance than the general dry gas treatment but had an efficiency drop with 1.5-4 μm particles. The PM₁₀-PCDD/F loads in the final adsorption-filtration unit were eased and effectively removed the PM₁₀-PCDD/Fs to sizes ≤0.5 or≥1.5 μm. The total TEQ_DE was 0.00052 ng WHO-TEQ Nm^-3 and had a peak level of 0.000157 ng WHO-TEQ Nm^-3 at 1.2 μm. PSDs were more sensitive to the PSDs of PM mass at high PM levels but strongly correlated with the PSDs of "PM₁₀-PCDD/Fs/PM₁₀" at low PM₁₀ loads. Consequently, the advanced control system could effectively remove the PM₁₀-PCDD/Fs and might extend the adsorption-filtration lifetime. However, the PM₁₀-PCDD/Fs ≤ 0.4 μm had a higher TEQ deposition rate and should be further considered in emissions and ambient air quality evaluations.

Keywords: Cyclone demister; PCDD/Fs; Particle deposition; Particle sized distribution; Scrubber.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Air Pollutants* / analysis
Benzofurans* / analysis
Dibenzofurans
Dibenzofurans, Polychlorinated
Dust
Environmental Monitoring
Hazardous Waste
Incineration
Polychlorinated Dibenzodioxins* / analysis
Respiratory System

Substances

Air Pollutants
Benzofurans
Dibenzofurans
Dibenzofurans, Polychlorinated
Dust
Hazardous Waste
Polychlorinated Dibenzodioxins