浮萍净化N·P污染性能的研究

Study on the Purification Efficiency of Duckweed on Nitrogen and Phosphorus Pollutes

[目的]明确浮萍净化污水TN和TP的特点，筛选高效净化氮磷有机污水的浮萍优化品种。[方法]从扬州市和昆山市各采样点选取的当地3种有代表性的浮萍品种为供试材料，以经稀释5倍、10倍的牛场厌氧废水为供试污水，设置5种不同浮萍对2种不同浓度污水的10组净化处理，在实验室条件下考察了不同浮萍品种对不同浓度污水氮和磷的净化效果。[结果]污水TN和TP浓度随浮萍处理时间（0～10d）增加而持续降低；紫萍属浮萍对TN和TP的净化能力优于浮萍属浮萍；浮萍对稀释5倍的供试污水TN和TP的最大去除率分别为71．14％和81．00％；浮萍对稀释10倍的供试污水TN和TP的最大去除率分别为92．18％和91．33％。[结论]紫萍属浮萍可作为适合长江三角洲地区的高效净化氮磷有机污水的浮萍优化品种。

[ Objective ] The study aimed to definite the characters of duckweed for purifying TN and TP in sewage and screen the optimized duckweed variety that could purify N and P effectively in organic sewage. [ Method ] With 3 kinds of representative local duckweed varieties selected from the each sample place in Yangzhou City and Kunshan City resp. as the tested materials and the anaerobic wastewater diluted at 5 times and 10 times from the cattle Farm as the tested sewage,10 groups of purification treatments matching with 5 different duckweeds on 2 concn, of sewage were set up to investigate the effect of different duckweed variety on the purification effect of N and P in sewage with different concn, under lab condition. [ Result ] TN and TP cohen, in the sewage were decreased constantly with the increase of duckweed treating time in 0 - 10 d. The purification ability of Spirodela Schleid on TN and TP was higher than that of Lemna L. The maximal removal rates of duckweed on TN and TP in sewage diluted at 5 times were 71.14% and 81.00% resp. and that in the sewage diluted 10 times were 92.18% and 91.33% resp. [ Conclusion] Spirodela Schleid could be taken as the optimized duckweed variety that was suitable to purify N and P effectively in organic sewage in Yangtze River delta region.