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2012~2013-Monitoring and management of dioxin, heavy metals and hazardous air pollutants

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Major works of this project included the emission source sampling of dioxin and heavy metals (Pb, Cd, and Hg), the emission source inquiry of dioxin, the analyses of ambient environment (air‚ leaves and soil), risk assessment, the emission source sampling of odor, regulation-disseminating campaign, guidance meeting of dioxin reduction, and technology transfer. The achievements of this project in 2012 are described as below: 1. This project was checked the information of 148 stacks. Most factories were corresponded to the regulation or operating condition of license. However, few factories have some miss, which will be checked in the next year. 2. The mean total PCDD/Fs concentration obtained from 39 emission sources are lower than the regulation limit of Taiwan EPA. However, the mean total PCDD/Fs concentration of stationary source WFB5-D (0.592 ng I-TEQ/Nm3) is higher than the regulation limit of Taiwan EPA (0.5 ng I-TEQ/Nm3). Because of the boiler and APCDs of WFB5-D were discontinued. 3. This project was choice twenty samples from the emission source of PCDD/Fs to analyze the pollutants, including PBDD/Fs, PBDEs, and PCDEs. The results revealed that some combustion sources of PCDD/Fs also contain the emission of PBDD/Fs, PBDEs, and PCDEs. Higher PBDE concentrations were obtained from various combustion sources, including power plants, secondary aluminum smelters, and electricfurnaces. 4. The existing emission sources of heavy metals (Pb, Cd, and Hg) were surveyed, including 2 MSWIs, 8 IWIs, 3 MWIs, 4 EAFs, 6 ALS, 1 VCM, 3 WFBs, 6 CFBs, 1 CEM and 1 DUC. The concentrations of heavy metals (Pb, Cd, and Hg) from 35 emission sources are lower than the regulation limit of Taiwan EPA. Compared with previous results, the concentrations of heavy metals of MSWIs, IWIs and MWIs are lower or constant. 5. The mean PCDD/F concentrations of ambient air, leaves and soil were 0.0282 pg I-TEQ/Nm3, 1.32 pg I-TEQ/g and 0.860 pg I-TEQ/g, respectively. The results indicated that the mean PCDD/F concentrations in Siaogang district were higher than other districts in Kaohsiung city. It might be due to the emission intensity and exhaust amount of factory. 6. In this project, the AERMOD model was applied to evaluate the concentration of dioxins and their dry and wet deposition in the environment, and then Human Health Risk Assessment Protocol (HHRAP) model was used to calculate the concentration of each environmental media and the amount of exposure in each pathway. By integrating these two models, it is estimated that risk contribution of dioxins and heavy metals emitted from stationary emission sources sampled and monitored in the exposure scenario with calculating site-specific transfer factors in 2011. The cancer risk values are ranged from 6.25E-10 to 1.97E-08, and the top three affected areas are located in Siaogang, Linyuan, and Nanzih districts. Moreover, the non-cancer risk values are ranged from1.38E-05 to 8.45E-05, and the first three affected areas are located in Lingya, Nanzih, and Siaogang districts. The districts located in northeast Kaohsiung are the lower-risk region in which Namasia district is the area accepting least cancer and non-cancer risk. 7. The odor samples obtained from 40 stack flue gases were lower than the regulation limit of Taiwan EPA. 8. The project invited the experts to give some evaluations and suggestions for 4 stationary sources in Kaohsiung city. The experts suggested secondary copper smelters need to reduce the chlorine compositions of feedstocks, such as coal and flux. For ALS, the feedstocks should be managed and APCDs need to maintain regularly. Black smog emmited from the stacks of two cremations would be caused by incomplete combustion. The cremations need to revise the operating conditions of combustion equipments.
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