闻陆鹏　崔康平　慈曾福等

摘要

随着南淝河清淤的结束，针对清淤及南淝河自身特点，考察南淝河清淤前后10个采样点水体中COD、TN和TP含量以及底泥中TN、TP、有机质和重金属等主要污染指标的变化。结果表明，由于河流污染的复杂性，对清淤效果的评估缺乏有效的预测和方法体系，清淤作为单一的治理措施从根本上很难改变南淝河水体的污染现状，水质依然会回到清淤前水准。清淤后，表层底泥中TN、TP和有机质含量的平均降幅分别为41.90%、41.96%和29.80%；由于河流底泥氮磷释放会造成水体污染，一定程度上缓解水体氮磷污染压力。清淤后Pb的最大去除率为58.5%，平均去除率达42.9%；Zn的最大去除率为86.4%，平均去除率51.2%；Cr的最大去除率为48.0%，平均去除率32.2%，很好地控制了重金属污染风险。

关键词 南淝河；清淤；水质；污染原因

中图分类号 S181.3；X703 文献标识码 A 文章编号 0517-6611（2015）15-199-03

The Changes of Main Pollution Indices before and after Nanfei River Dredging

WEN Lupeng1， CUI Kangping1*， CI Zengfu2 et al

（1. School of Resources and Environmental Engineering， Hefei University of Technology， Hefei， Anhui 230009； 2. Hefei Municipal Drainage Management Office， Hefei， Anhui 230001）

Abstract With the end of Nanfei River dredging， aiming at dredging and Nanfei River characteristics， the content of COD， TN， TP and variation of main pollution indices（TN， TP， organic matter and heavy matter） in 10 sampling sites before and after dredging were investigated. The results showed that， due to the complexity of river pollution， assessment of the effect of dredging lack of effective prediction method system， dredging as a single treatment measure was fundamentally difficult to change Nanfei River water， water quality will still return to former levels. The average dropped on the surface of sediment dredging in TN， TP and organic matter were respectively 41.9%， 41.96% and 298%； the release of nitrogen and phosphorus in river sediment will cause water pollution， to some extent alleviate the pressure of nitrogen and phosphorus pollution. After dredging Pb the maximum removal rate was 58.5%， the average removal rate of Zn reached 42.9%； the maximum removal rate was 86.4%， the average removal rate was 51.2%； the maximum law of averages 48% Cr， the average removal rate of 322%， very good control of the risk of heavy metal pollution.

Key words Nanfei River； Dredging； Water quality； Pollution causes

南淝河是合肥的母亲河，贯穿合肥市，有着其特殊的地位和重要性[1]，一直以来，南淝河吸纳着合肥市大量的生活、生产等废水，其水质的优劣也深受广大市民的关注。河底淤泥富含多氮、磷等物质以及有机质[2]，可以通过聚磷菌和其他的细菌作用进入河水中，释放到上覆水中，容易引起河水富营养化，造成河道的污染，另外底泥中还含有大量的重金属，底泥污染严重[3]。 清淤作为控制水体富营养化的一种措施，可以有效保证水体质量，清除沉积物中所含的多氮、磷等物质以及有机质，减少沉积物中的污染物向水体中排放[4]。合肥市在2000年前后曾利用河道疏浚工程清理过南淝河河底淤泥，而在这之后除了小规模的清淤外就再也没有大规模地清理过。……