Integrating satellite information, land use regression, and machine learning to estimate the spatiotemporal variation of ionic composition in PM across Taiwan.

The growing understanding of PM compositions has promoted the application of machine learning in exposure estimation. However, data-driven approaches may neglect the necessity for expert knowledge. This study presents a theory-guided approach combining land use regression (LUR), extreme gradient boosting (XGBoost), and Shapley additive explanations (SHAP) to estimate the spatiotemporal variation of ionic PM in Taiwan.

Gasification-MILD combustion technology with ash-sludge recirculation for reducing multi-phase net dioxin discharges from a waste incineration.

This study addresses the challenge of reducing "net" toxic pollutant discharge, specifically dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), while minimizing the energy consumption and costs associated with detoxification. Our research focuses on reintroducing fly ash and scrubber sludge (ASR) into a hazardous waste thermal treatment system equipped with gasification-intense low oxygen dilution (GASMILD) and an advanced air pollution control system (APCS). This approach yielded a remarkable PCDD/F removal efficiency exceeding 99.

Mitigation of PBDE net discharge in hazardous waste thermal treatment system through reintroducion of sludge and fly ash into GASMILD operations.

The presence of polybrominated diphenyl ethers (PBDEs) in consumer products, waste treatment processes, and treated ashes poses a significant environmental threat. Due to the lack of research on the removal of PBDEs during waste incineration, this study investigated the effectiveness of a Hazardous Waste Thermal Treatment System (HAWTTS) utilizing reburning of sludge and fly ash (SFA) with gasification-moderate or intense low-oxygen dilution (GASMILD) combustion for PBDE removal. The closed-loop treatment of sludge and ash within the HAWTTS provides a potential pathway for near-zero PBDE emissions.

Emissions of polychlorinated diphenyl ethers from a municipal solid waste incinerator during the start-up operation.

This study examines the emissions of polychlorinated diphenyl ethers (PCDEs) during the start-up processes of a municipal solid waste incinerator (MSWI). Both normal and modified emission control start-ups were tested. Fifteen samples were taken from the flue gas with increasing furnace temperature.

An analysis of extinction coefficients of particles and water moisture in the stack after flue gas desulfurization at a coal-fired power plant.

Two important factors that affect in-stack opacity--light extinction by emitted particles and that by water moisture after a flue gas desulfurization (FGD) unit--are investigated. The mass light extinction coefficients for particles and water moisture, k(p) and k(w), respectively, were determined using the Lambert-Beer law of opacity with a nonlinear least-squares regression method. The estimated k(p) and k(w) values vary from 0.

Atmospheric deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans on the soils in the vicinity of municipal solid waste incinerators.

This study focuses on the atmospheric deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) on the soils in the vicinity of two municipal solid waste incinerators (MSWIs), which were located in the Gangshan (GS) and the Renwu (RW) Townships of southern Taiwan. PCDD/Fs in the soils were sampled simultaneously with those in the ambient air and analyzed for 17 2,3,7,8-substituted PCDD/Fs. The results show that the mean contents of PCDD/Fs in the soils near MSWI-GS and MSWI-RW were 2.

Metal interference on luciferase activity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin in bioassays of recombinant mouse hepatoma cells.

This study will examine the effect of a series of metals on the luciferase activity expression induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) in H1L6.1 cells. A 2-level factorial design was employed to identify major influential metal species of four test metals (As(5+), Cr(6+), Cd(2+), and Pb(2+)) in the chemically activated luciferase expression (CALUX) of H1L6.

Human dietary exposure to polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in Taiwan.

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) levels in a total of 25 food items in Taiwan were surveyed. It was observed that shellfish and saltwater fish possessed the highest PCDD/Fs levels, 9.82 and 3.

Atmospheric dry deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans in the vicinity of municipal solid waste incinerators.

This study focuses on the atmospheric dry deposition flux of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the vicinity of the two municipal solid waste incinerators (MSWIs) located in southern Taiwan. PCDD/Fs in ambient air were taken and analyzed for seventeen 2,3,7,8-substituted PCDD/Fs during November 2004 and July 2005. Results show that the mean concentrations of PCDD/Fs in the ambient air near MSWI-GS and MSWI-RW were 0.

Fate of polychlorinated dibenzo-p-dioxins and dibenzofurans in a fly ash treatment plant.

To understand the fate of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in a fly ash treatment plant that used the Waelz rotary kiln process (hereafter the Waelz process), the samples of input and output media were collected and analyzed. The most important PCDD/F source in input mass was electric arc furnace (EAF) fly ash, which had a mean PCDD/F content of 18.51 ng/g and contributed more than 99% of PCDD/F input mass, whereas the PCDD/F input mass fractions contributed by the coke, sand, and ambient air were only 0.

Vertical ozone distributions observed using tethered ozonesondes in a coastal industrial city, Kaohsiung, in southern Taiwan.

This work presents the vertical distributions of ozone and meteorological parameters observed with tethered ozonesondes and meteorological radiosondes in the lower atmosphere during an ozone episode on March 25-27, 2003, in Kaohsiung City in southern Taiwan. Kaohsiung is a coastal industrial city with inland mountain ranges to the east. Extremely complicated ozone structures were identified that spanned day and night during the experimental period.