城市污水处理厂排水对河流沉积物的影响

Urban Sewage Treatment Plant Drainage to the Research on the Effects of River Sediment

通过对距城市污水处理厂排水口下游约500 m、1000 m、1500 m处的沉积物进行实验分析,得出城市污水处理厂排水对河流沉积物理化性质的影响(以合肥市某城市污水处理厂为研究对象)。研究表明,随着离城市污水处理厂排水口距离的变化,沉积物的理化性质呈现出一定变化规律:沉积量随着离排水口的距离增加而减少,泥质由黑色粘稠状逐渐向黄灰色砂质变化。随季节变化,沉积物的理化性质也会有一定的变化。沉积物中所含的TP、TN和有机质随着离排水口的距离增加而减少,其冬季高于夏季含量约20%,可能是冬季温度低微生物活动减弱所造成。各个收样点不同时间段的沉积物粒径分布主要集中于4到63微米之间,所占比例接近于50%,距离排水口近收样点的沉积物粒径大于500微米的含量接近于0,较远的收样点大粒径的含量有所增加。距排水口较近收样点的沉积物间隙水含量较高,但是TS和VS(基于TS)的含量随距离变化的影响不明显。季节的变化对VS的影响比较明显,夏季沉积物中VS的含量比冬季高出10%左右。

Of urban sewage treatment plant outfall from about 500 m and 1000 m and 1500 m downstream of sediment experiment analysis, it is concluded that urban sewage treatment plant drainage effect on the physical and chemical properties of river sediment（in hefei city sewage treatment plant as the research object）. Studies have shown that as the distance from the city sewage treatment plant outfall than change, the physical and chemical properties of sediment presents a certain change rule： sedimentary decrease with increasing distance from the drain, argillaceous has black, sticky gradually change to yellow grey sandy.The seasons change, the physical and chemical properties of sediments have certain changes. TP, TN and organic matter in sediments and reduce with increasing distance from the drain, the winter than the summer content about 20 % and may be winter low temperature caused by microbial activity.Each received points in different periods of sediment particle size distribution is mainly focused on 4 to 63 microns, the proportion of close to 50 %, close drain to collect samples of sediment particle size is larger than 500 microns levels close to zero, the received far points in the content of large particle size increases.Of sample from port relatively close to the sediment interstitial water content is higher, but the TS and VS（TS） based content changing with distance effect is not obvious.The obvious seasonal changes impact on VS, summer sediments VS content is about 10 % higher than in the winter.