| 溶质迁移模型在地下水有机污染源识别中的应用 |
| 摘要点击 2115 全文点击 1361 修订日期：2011-09-30 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 地下水 四氯乙烯(PCE) 三氯乙烯(TCE) RT3D 多元回归分析 |
| 英文关键词 groundwater PCE TCE reactive transport in 3-dimensions (RT3D) multiple regression analysis |
|
| 中文摘要 |
| 采用现场调查与数值模拟的方法,借助RT3D(reactive transport in 3-dimensions),对我国北方某城市局部地区地下水中的四氯乙烯(PCE)和三氯乙烯(TCE)污染来源进行了识别,对污染输入强度进行了反演,并利用Matlab中的Stepwise函数,对影响污染物输入强度的因素进行了多元回归分析.研究结果显示,研究区地下水中的PCE和TCE主要来源于区内使用有机溶剂的工厂和企业.地下水中的PCE和TCE存在天然衰减,在173天中, 3个点的PCE浓度分别衰减了93.15%、61.70%和61.00%; TCE分别为70.05%、73.66%和63.66%.通过模拟识别出的4个点状污染源在模拟期间共向含水层中输入0.9106 kg PCE和95.6938 kg TCE.回归分析结果显示,大气降水与包气带厚度是有机物输入地下水的主要影响因素.35 cm深的包气带中PCE和TCE浓度介于0~5 mg·kg-1之间.以上结果表明,区内地下水中PCE和TCE来源于地表释放的有机污染物.有机污染物一部分在向下迁移过程中自然衰减了,一部分进入包气带,然后又进入了含水层.由于本区第四系以砂卵砾石为主,所以大气降水促进了PCE和TCE向含水层的迁移. |
| 英文摘要 |
| Investigation and numerical simulation, based on RT3D(reactive transport in 3-dimensions)were used to identify the source of tetrachloroethylene (PCE) and trichloroethylene (TCE) in the groundwater of a city in the north of China and reverse the input intensity. Multiple regressions were applied to analyze the influenced factors of input intensity of PCE and TCE using Stepwise function in Matlab. The results indicate that the factories and industries are the source of the PCE and TCE in groundwater. Natural attenuation was identified and the natural attenuation rates are 93.15%、61.70% and 61.00% for PCE, and 70.05%、73.66% and 63.66% for TCE in 173 days. The 4 source points identified by the simulation have released 0.9106 kg PCE and 95.6938 kg TCE during the simulation period. The regression analysis results indicate that local precipitation and the thickness of vadose zone are the main factors influencing organic solution transporting from surface to groundwater. The PCE and TCE concentration are found to be 0 and 5 mg·kg-1from surface to 35 cm in vadose zone. All above results suggest that PCE and TCE in groundwater are from the source in the surface. Natural attenuation occurred when PCE and TCE transporting from the surface to groundwater, and the rest was transported to groundwater through vadose zone. Local precipitation was one of the critical factors influencing the transportation of PCE and TCE to aquifer through sand, pebble and gravel of the Quaternary. |
|
|
|
