【作者】 杨志；

【导师】 章北平；

【作者基本信息】 华中科技大学 ， 建筑与土木工程， 2017， 硕士

【摘要】 城市化的高速发展,必然伴随着环境问题的日益严峻,水环境污染是发展过程中不可避免的环境问题。水环境污染中除了氮磷营养元素、悬浮颗粒物等常规污染物,多环芳烃等持久性有机污染物因其高毒性而受到了大家的广泛重视。本文选取武汉市青山区和洪山区作为采样区域,以常规污染物及多环芳烃为研究对象,对其污染特征进行研究分析,并对多环芳烃进行来源解析。对于降雨径流中的常规污染物,两城区表现出一致性,但略有差别。从不同的下垫面因素对比来看,pH基本呈弱碱性;悬浮颗粒物浓度(SS)与电导率在路面径流明显高于屋面径流;碳氮元素在油毡屋面与沥青屋面径流中浓度最高,路面径流次之,瓦屋面和水泥屋面径流中最低,与《地表水环境质量标准》对比的结果显示,几乎所有的下垫面径流均达到Ⅴ类水或劣Ⅴ类水,污染较为严重。对于降雨径流中多环芳烃,不同下垫面中多环芳烃的场次降雨径流事件平均浓度(EMC)由大到小依次为:水泥屋面>水泥路面>沥青路面>瓦屋面/琉璃瓦屋面>广场>停车场>油毡屋面>沥青屋面;低环组分占比较高,平均在80%以上,中高环组分浓度较低。四环组分浓度由大到小依次为:芘>苯并(a)蒽>荧蒽>?,五至六环组分中,茚并(123-cd)芘浓度最高。中高环组分在屋面径流中浓度由大到小依次为:油毡屋面/沥青屋面>琉璃瓦屋面>瓦屋面>水泥屋面,在路面径流中浓度由大到小依次为水泥路面>沥青路面>停车场/广场。初始冲刷效应在各下垫面普遍存在。降雨特征、下垫面材料及使用年限、下垫面周围条件、交通情况、污染物累积程度及大气污染状况等对污染物浓度及初始冲刷效应存在较大影响。使用特征比值法对两城区降雨径流中多环芳烃的来源进行初步判定,来源为不完全燃烧源和石油泄漏源的混合源。进而使用主成分分析/多元线性回归模型(PCA/MLR)和正定矩阵因子分解模型(PMF)对水样中多环芳烃来源进行定量解析,两种模型得到的结果较为接近,化石燃料的燃烧、机动车排放及石油泄漏和挥发是降雨径流中多环芳烃的主要来源,并计算得到各来源贡献率。更多还原

【Abstract】 The rapid development of urbanization was bound to be accompanied by the increasingly serious environmental problems.Water environmental pollution was an inevitable environmental problem in the development process.In addition to the conventional pollutants such as nitrogen and phosphorus nutrients,suspended particulates,polycyclic aromatic hydrocarbons and other persistent organic pollutants have absorbed widely attention because of their high toxicity.In this paper,the Qingshan District and Hongshan District of Wuhan were selected as the sampling areas.Conventional pollutants and Σ15PAHs were selected as the research objects.The pollution characteristics of pollutants and sources apportionment of Σ15PAHs were analyzed.For conventional pollutants in rainfall runoff,the two urban areas showed consistency,but slightly differed.For the contrast of different underlying surfaces,pH was basically weak alkaline,the concentration of SS and the conductivity in road runoff were significantly higher than in the roof runoff.The carbon and nitrogen elements had the highest concentration in the runoff of the linoleum roof and the asphalt roof,followed by road runoff.The lowest concentration was in the runoff of tile roof and cement roof.The result of comparison with "surface water environmental quality standard" showed that almost all of the underlying surface runoff were of grade Ⅴ or inferior Ⅴ water.The pollution was serious.For Σ15PAHs in rainfall runoff,the order from large to small of the EMC concentration of Σ15PAHs in different underlying surfaces was cement roof> cement pavement > asphalt pavement > tile roof / glazed tile roof > square > parking lot > linoleum roof > asphalt roof.Low-ring components accounted for a higher proportion,more than 80% in average.The concentration of medium and high-ring components was low.The concentrations of 4 rings were in the order of PYR > BaA > FLA > CHR.The concentration of IcdP was the highest in 5-6 ring components.The concentrations of medium and high ring components from large to small in roof runoff were: linoleum roofing / asphalt roofing> glazed tile roof > tile roof > cement roof,in the road runoff were: cement pavement > asphalt pavement > parking lot / square.The first flush effect was common in every underlying surface.Rainfall characteristics,underlying surface material and service life,the surrounding conditions of underlying surface,traffic conditions,the accumulation of pollutants and air pollution conditions had great impact on the concentration of pollutants and the first flush effect.Using the characteristic ratio method,the sources of PAHs in rainfall runoff of two urban areas were preliminary determined.The source was a mixed source of incomplete combustion source and oil leakage source.PCA/MLR and PMF were used to quantitatively analyze the sources of PAHs in rainfall runoff.The results obtained by the two models were close to each other.The combustion of fossil fuels,motor vehicle emissions and oil spill and volatilization were the main sources of PAHs in rainfall runoff and the contribution rate of each source was calculated.更多还原