人工介质对富营养化水体中氮磷营养物质去除特性研究

Performance of artificial medium for removing nutrients in eutrophic water

采用人工介质富集微生物对太湖梅梁湾水源水中氮磷营养物质的去除特性进行了试验研究．中试结果表明：随着介质密度和水力停留时间的增加,对氮磷营养物质的去除率均有提高．介质密度为26．8%、水力停留时间为5d时,人工介质对TN、TP、氨氮、亚硝态氮的去除率分别为26．6%、72．1%、43．2%、79．4%,可见人工介质对富营养化水体中氮磷营养物质有较好的去除效果．增加水流速度消除了池内的溶解氧和氧化还原电位的分层现象,提高了NH_4^+-N和NO_2^-N的去除效果,没有降低TP、PO_4^(3-)-P、DTP的去除效果,说明沉淀作用并不是去除水体中氮磷营养物质的主要途径．人工介质表面富集了大量的微生物,通过硝化-反硝化作用是富营养化水体水质改善的主要途径．

Pilot test was made for the removal of nutrients in eutrophic source water through the use of enriched microbes by artificial medium. The results indicated that the nutrient elements removal efficiency enhanced as the medium density and hydraulic retention time （HRT） increased. The removal rates of total nitrogen （TN）, total phosphorus （TP）, ammoniacal nitrogen, nitrite nitrogen were 26.6%, 72.1%, 43.2% and 79.4% respectively under the medium density of 26.8% and HRT of 5d. It is evident that enriched microbes on the artificial medium can effectively remove the nutrient elements in the eutrophic source water. Because of increasing the water velocity, the delimination phenomena of the dissolved oxygen （DO） is lowered and oxidation-reduction potential （ORP） is eliminated. The removal ratio of ammonia nitrogen, nitrite nitrogen was enhanced slightly whereas the elimination effect of TP, phosphate, dissolved total nitrogen （DTN） did not. So the sedimentation isn＇t the main approach of nutrient elements removal in source water. The large quantity of microbes is enriched on the surface of artificial medium. The nitrification and denitrification is one of the main mechanisms for water quality improvement in eutrophic water.