【摘要】：大氣干濕沉降是大氣中污染物去除的主要方式。本研究采集了太原市2013年8月到2014年10月期間的干沉降和雨水樣品,分析和報道了其中16種優(yōu)控PAHs水平,探討了干沉降和雨水中PAHs分布特征和影響因素,并進(jìn)一步估算了太原市PAHs干沉降和雨水通量及生態(tài)風(fēng)險,為了解太原市大氣PAHs干沉降和雨水去除機制和環(huán)境地球化學(xué)效應(yīng)提供基礎(chǔ)數(shù)據(jù)。主要得出以下結(jié)論:(1)干沉降中PAHs水平為19.61~61.91μg/g,均值為33.85μg/g。2~3環(huán)、4環(huán)和5~6環(huán)PAHs所占百分比分別為54.56%、29.12%和16.32%。(2)濕沉降(雨水)中總PAHs(溶解態(tài)+顆粒態(tài))水平為965.97~44393.80 ng/L,溶解性PAHs為350.90~10704.0 ng/L,顆粒態(tài)PAHs為332.45~35532.68 ng/L。顆粒態(tài)PAHs占總PAHs的67.28%。2~3環(huán)PAHs在總PAHs、溶解態(tài)PAHs、顆粒態(tài)PAHs中所占百分比分別為67.56%、70.97%、65.54%。(3)PAHs干濕沉降通量為6560.90~16289.60 ng/(m2·d),其中干沉降通量為4196.4~14769.8 ng/(m2·d),濕沉降沉降通量為319.98~10608.0 ng/(m2·d)。大氣干沉降是太原市大氣PAHs的主要去除方式。據(jù)此,2013年太原市大氣PAHs干濕沉降總量為31.57t,其中干沉降為23.90 t,濕沉降為7.67 t。(4)BaP的毒性當(dāng)量濃度分析顯示,干沉降中16種PAHs的TEQ濃度范圍為0.86~2.80μg/g,雨水中16種PAHs的TEQ濃度范圍為26.94~2456.28 ng/L。值得注意的是,所有雨水樣品中BaP毒性當(dāng)量濃度均高于國家地表水相關(guān)標(biāo)準(zhǔn)限值,具有較高的生態(tài)風(fēng)險。生態(tài)效應(yīng)區(qū)間法對干沉降中PAHs進(jìn)行風(fēng)險評價發(fā)現(xiàn)處于中等或較高生態(tài)風(fēng)險。(5)PAHs特征比值顯示干濕沉降中PAHs主要來自燃煤和石油源。主成分分析顯示燃煤、機動車尾氣、煉焦是太原市干濕沉降中PAHs三個主要來源。
[Abstract]:Atmospheric dry and wet deposition is the main way to remove pollutants from the atmosphere. In this study, dry deposition and Rain Water samples from August 2013 to October 2014 in Taiyuan City were collected, 16 kinds of optimized PAHs levels were analyzed and reported, the distribution characteristics and influencing factors of PAHs in dry deposition and Rain Water were discussed, and the dry deposition and Rain Water flux and ecological risk of PAHs in Taiyuan were further estimated, which provided basic data for understanding the mechanism of atmospheric PAHs dry deposition and the removal mechanism of Rain Water and environmental geochemistry effects in Taiyuan. The main conclusions are as follows: (1) the level of PAHs in dry deposition is 19.61 ~ 61.91 渭 g / g, the mean value is 33.85 渭 g / g 路2, the percentages of PAHs in 4 rings and 5 鈮，

本文編號：2506912