Experimental Study On Quality Guarantee Of Urban Lakes Water Landscape By Constructed Wetland

With the fast development of modern society, the water pollution has become a serious problem, especially the reality of low concentration, area of non-point pollution problem has already become the archcriminal of (e.g. rivers, lake etc) the water quality deterioration to surface water.In developed countries, such as Europe and USA, the using of artificial wetland to handle the related research and technology rain is developing fast, and get the attention of governments. But in China, the research of using artificial wetland handle stormwater runoff also less. Due to our country economy is still not developed well, so the low cost of artificial wetland light pollution treatment of large-scale water is suitable for our country situation. However, our country over a vast territory, the weather and climate is different, topography characteristic is differ in thousands ways, so, in different places should to combine with local actual condition of experiment research, in order to explore and local situation of artificial wetland is consistent with the related conditions and stormwater runoff valuable parameters.Research content includes three aspects:â‘ Water area ground stormwater runoff characteristic monitoring analysis of the palm springs residential district.â‘¡Removal characteristics of various kinds of pollutant for artificial wetland in constant load all the year.â‘¢Influent and effuent pollutants changes characteristic of the artificial wetland in the shock load.Papers made the following main research results:â‘ The four basic pollutants from monitoring stations, pollutants concentration in SS and COD each rainfall concentration is high, is the main pollutant of stormwater runoff. From three kinds of pollutant concentration of absolute value of rainfall, found cumulating sunny days in different rainfall, the initial pollutant density has a great deal of difference. From the graph on changes in rainfall contaminants each pollutant concentration, rainfall early to rise, reached a peak, the specification has obvious effect of the initial. On June 19th, such as the highest concentrations of CODcr even reached at 176mg/L, while in the reduced gradually, die down until to stable.â‘¡The annual artificial wetland test run of 220 days,idle 145 days at shut-down period , palm lake water relatively keeping stable operation all year-round, annual rainfall of artificial wetland under the impact load has 22 days, the number of inlet running 10% of artificial wetland all year-round. Professing artificial wetland is still in a relatively constant water load operation most of the time. Impact load mainly concentrated in the summer monsoon rains. Issue of artificial wetland of palm springs has good rejection to all classes of pollutants when in constant duty, except TP, rejection of SS,NH4+-N all in advance of 80%, effluent mean of all classes of pollutants are superior to the average urban sewage recycle water lake landscape appreciation of water quality requirements GB/T18920-2002) and surface water environment quality requirements of lakesâ…¤class(GB3838-2002) . SS of effluent can keep under 20mg/L all the year round after the treatment of artificial wetland. Total rejection keep from 83% to 90%, maintain high levels of removal. This can be professed that the plants and packing of artificial wetland have strong filtering and tackle to SS. Removal of NH4+-N in the artificial wetland has high consistency with the removal of total nitrogen. Removal efficiency of CODCr keep stable all year-round, hardly be influenced by the changes of temperature&season. Although the total rejection on TP isn,t ideal, but summer has the highest removal efficiency of the year, in advance of 65%.â‘¢Impact load for the two sequence of rainfall, sunny days cumulating long,it will make total rainfall has more storage capacity for ASV, make wetland has effective detention, cushion and cut under the condition of heavy rain, be equal to strengthen the contact time of artificial wetland and runoff, and improve the treatment effect. On July 26th, heavy load test of shock, due to the impact load in successive pool formed surface short flows phenomenon, make later rain directly into the artificial wetland, artificial wetland due to the processing function, performance at CODCr, NH4+-N and TP in shock loading for low concentration area, especially such as flow initial producing NH4+-N and TP concentration even more than the NH4+-N and TP concentration of inflow. When the inflow of artificial wetland recover to the rain after afthomogenisation of storage pond by pumping, the inflow pollutants concentration except SS, all to rising at a extent and then flatten out.