浑河沈阳城区段下游底泥污染物释放试验

Experimental Study on Contaminated Sediment Releasing in Downstream of the Hunhe River of Shenyang

目的研究温度及pH值对底泥污染物释放的影响,分析浑河沈阳城区段下游底泥污染物的释放规律.方法采用浑河沈阳城区段下游四个断面底泥进行静态试验,分析静止状态、不同温度、不同pH值下底泥污染物(CODCr和NH4+-N)的释放规律.结果静止状态下,铁路大桥断面底泥CODCr和NH4+-N释放量最大,公相屯断面最小;30℃时比4℃时各断面底泥CODCr和NH4+-N释放量大、释放速率快;pH值为10比pH值为4更易于底泥污染物CODCr和NH4+-N的释放.结论底泥污染物释放与底泥污染程度有关,污染程度越高则释放能力越强;水温高促进底泥中CODCr和NH4+-N的释放,水温低抑制底泥中CODCr和NH4+-N的释放;酸性条件与碱性条件比较,碱性条件能促进底泥中CODCr和NH4+-N的释放.

The purpose of this study is to research the influence of different temperatures and pH values on contaminated sediment releasing,and analyze its regulations in downstream of the Hunhe River of Shenyang.By the static experiment on contaminated sediment of four cross sections in downstream of the Hunhe River of Shenyang,regulations of contaminated sediment releasing were analyzed under stationary state,different temperatures and pH values.The results are showed as follows.In static state,the release values of CODCr and NH＋4-N were the greastest in Railway Bridge section,and which were the least in Gongxiang Tuen section.The release values of CODCr and NH＋4-N in 30℃were greater than in 4℃,and the release rates of CODCr and NH＋4-N in 30 ℃ were faster than in 4 ℃.The CODCr and NH＋4-N in sediment in pH=10 were easier to release than in pH=4.This study clearly indicates that contaminated sediment releasing are related to the pollution level of contaminated sediment,the higher level of pollution is,the stronger the ability of releasing will be.The release of CODCr and NH＋4-N in sediment is promoted in the high temperature and it is inhibited on the contrary condition.Comparing different conditions of acidic and alkaline,the release of CODCr and NH＋4-N in sediment is promoted in the alkaline conditions.