Characterics of PAH Emission from the Asphalt Plants

• Main Authors: Wen-Hui Chao, 趙雯蕙
• Other Authors: Wen-Jhy Lee
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/80364284683700151423

碩士 === 國立成功大學 === 環境工程學系 === 88 === The characteristics of PAH (polycyclic aromatic hydrocarbon) emission from the asphalt plants were investigated. Samples were collected from six asphalt plants located at the eastern Taiwan. The samples of flue gas from six stacks of asphalt concrete mixers (S) and one stack of the asphalt heater (H), ambient air samples from unloading port (M) and from the boundary of plants, and from the fly ashes of the air pollution control devices (APCDs) are also collected and analyzed. Major results are as follows: (1) the mean concentration of total PAHs, ΣHM-PAHs and BbF+BaP+DBA are 3430, 90.5 and 2.54μg/Nm3, repectively. Since there are residents living near the asphalt plant, the emission of PAHs may cause adverse effect to the people. (2) Mean concentration of total-PAHs in the ambient air of unloading port is up to 6340 ng/m3, and may result in harmful health effect on the workers in the asphalt plants. This point need to be assessed in the future. (3) Mean emission factor (EF) for total PAHs, ΣHM-PAHs and BbF+BaP+DBA of the asphalt plant (S+H+M) are 2660, 402 and 4.55 mg/ton-product, respectively. Among these three major sources, S has major contribution on total-PAH emission. The contribution fraction of EF by S is up to 77.6 %. However, the unloding port of asphalt concrete (M) played a vital role on the emission ofΣHM-PAHs; its contribution fraction of HM-PAH EF is 84.3 %. (4) Mean removal efficiencies of total-PAHs by cyclone and bag-house are 6.68 % and 2.57 %, repectively. Both cyclone and bag-house have higher removal efficiencies forΣHM-PAHs. However, these two APCDs have very low removal effiiencies for the low molecular weight PAHs in the gas phase.