EPA-107-L102-02-A038

107

3,800 千元

科技發展-環境科學及技術之研究

2018/01/29

2018/12/31

周崇光

監資處

黃健瑋

中央研究院 環境變遷研究中心

環境監測及檢測

同位素、細懸浮微粒、污染來源鑑識

Isotope, PM2.5, Air Pollution Forensics

李崇德；張士昱

黃譯樘

02-27875983#

yitang@rcec.sinica.edu.tw

本計畫主要目的為應用前期計畫建立之PM2.5中的碳與鉛同位素分析技術，分析台中與彰化地區的重要污染源及大氣PM2.5的碳與鉛同位素特徵，並結合前期計畫的研究成果，評估台灣中南部地區 (台中、彰化、南投、雲林和嘉義) 的PM2.5污染來源。 本年度計畫增加台中與彰化地區的火力發電廠、鋼鐵廠和焚化爐三種污染源排放之PM2.5的採樣和化學組成的分析，結果顯示：1.) 鋼鐵廠和火力發電廠的分析結果顯示金屬元素有較高的貢獻量，其中鋼鐵廠排放的硫酸鹽約佔PM2.5質量濃度的13%；此外，排放的碳以化石碳為主，2.) 焚化爐排放的PM2.5濃度低於偵測極限 (< 172 μg/m3)，但化學組成分析結果顯示金屬元素是主要的組成。三種污染源的鉛同位素比值範圍廣泛。周界PM2.5 (豐原、大里、沙鹿、彰化和線西站) 的傳統化學組成分析結果顯示硫酸鹽、硝酸鹽、銨鹽和碳是重要的組成，顯示光化反應和燃燒行為是重要的污染成因。同位素特徵分析結果顯示，春季和夏季的δ13C數值無顯著差異，兩個季節的14C分析結果則顯示平均現代碳比例 (pMC) 分別為47%和48%，但鉛同位素比值有明顯的季節差異。綜合前期計畫與本期計畫共13個測站和7個污染源的碳與鉛同位素和PMF的分析結果，推論生質燃燒、工業排放 (煉油廠、鋼鐵廠、燃煤電廠與焚化爐) 和交通排放是重要的貢獻源，但不同測站的主要污染源不同。比較同位素與PMF的分析結果，本研究發現碳同位素與PMF的結合可增加碳污染源的鑑定能力，但鉛污染源需其他技術來提高污染源的鑑定效益。

同位素、細懸浮微粒、污染來源鑑識

EPA-107-L102-02-A038 期末報告.pdf

14MB

期末報告

2019/2/1 上午 12:00:00

The objectives of this study was to analyze the characteristics of carbon and lead isotope composition in fine particulate matters (PM2.5) and, in turn, identify the potential sources of PM2.5 in the central-southern Taiwan area with the isotopic fingerprints. During the period from the spring of 2018 to the summer of 2018, the ambient PM2.5 samples were collected at 5 sampling stations (Fengyuan, Dali, Shula, Changhua, and Xianxi sampling stations). In addition, this study also collected PM2.5 samples from 3 specific sources: coal-fired power plant, steel plant, and incinerator. The results reveal that the metals were the predominant species in the PM2.5 emitted from three specific sources. The particulate carbon emitted from the coal-fired power plant and steel plant were composed mostly of fossil carbon. The major constituents of the ambient PM2.5 in the study area included nitrate, sulfate, ammonium, and carbon. These results implied that photochemical reactions and burning activities were important cases of high PM2.5 level in the Taichung and Changhua areas. The averages of δ13C for ambient PM2.5 are -25.7‰ (-28.2 to -23.6‰) and -25.1‰ (-28.7 to -20.7‰) in the spring and summer, respectively. The pMC measurements indicated that the contributions from both fossil carbon and modern carbon were similar. The 206Pb/207Pb ratios were 1.1522 (1.1415~1.1638) and 1.1522 (1.1415~1.1638) in the spring and summer, respectively, and 208Pb/207Pb ratios were 2.4335 (2.4145~2.4507) and 2.4335 (2.4145~2.4507). Our results indicated that biomass burning, steel plant, coal-fired power plant, and incinerator were major pollution sources in south-central Taiwan area based on isotopic compositions and PMF analysis. In this study, we also compared the results on the pollution source identification between isotopic compositions and PMF. We found that the combination of carbon isotope and PMF can provide clear information on pollution source identification for carbon. However, it is necessary to use other technology for Pb pollution source identification.

Isotope, PM2.5, Air Pollution Forensics