The Study And Application For Compound Constructed Wetland To Protect The Water Source Of Yuecheng Reservoir

In recent years, the water pollution problem is prominent in our country, and thedeterioration of water quality, water management problems should to be solved, thedemand for more efficient wastewater treatment technology is growing. Constructedwetland is a new sewage treatment technology developed in the1970s. Its principlescome from the natural wetland systems, and enhanced by artificial design, It uses thesynergies effect of plants, matrix and microorganisms to purify the sewage. It is widelyapplied in the control of non-point source pollution, all kinds of industrial wastewaterand domestic sewage treatment, purification and remediation of polluted rivers andlakes. This paper adopted two groups of compound constructed wetland which hadconducted a series of research on micro polluted river water. Through the experiments,analysis the purification effect of different pollutants in the artificial wetland, providethe scientific basis for the constructed wetland research, engineering design andoperation. By analyzing the change of different pollutants in constructed wetland alongtime and, the dynamic model is established. After the analysis of experimental data, themain results obtained are as follows:(1) The average removal of total phosphorus, turbidity, nitrate nitrogen, nitritenitrogen, total nitrogen, permanganate index rates in composite wetland1were:89%,93%,34.7%,89.4%,36.3%,46.5%.(2) The average removal of total phosphorus, turbidity, nitrate nitrogen, nitritenitrogen, total nitrogen, permanganate index rates in composite wetland2were:80.8%,84.3%,49.5%,97.4%,35.9%,50.4%.(3) The average PH value of the raw water was8.40in composite wetland, and theoutlet water PH value was8.07,8.06in the two composite wetlands.(4) Based on the research of the pollutant concentration changes along the way,finding biological ponds played a lesser role in decontamination, but in reducing thepollution load and high total removal rate, played a certain role. And its main purposewas to remove suspended substances, reduce the subsequent wetland load, preventwetland clogging, provide the source of carbon and dissolved oxygen for other wetlandunits. (5) Except cattail emergent plants pond, the removal of total phosphorus andturbidity are very good in the reed wetland, composite vertical flow wetland, stonecalamus subsurface flow wetland, canna subsurface flow wetland, ordinary vertical flowwetland, the removal rates were95%,98%; the effect of removing the total nitrogen andnitrate nitrogen is best in the reed wetland, the removal rate is49%,76.9%;the effect ofremoving the permanganate index was best in canna subsurface flow constructedwetlands, the removal rate is58.9%.(6) The removal rates of permanganate index, total nitrogen and nitrate nitrogen inthe reed subsurface flow wetland were better than other wetlands, the kVvalues were0.182,0.213,0.46; the correlation coefficient R values were0.896,0.909,0.915. Theremoval rate of phosphorus and turbidity in the composite vertical flow wetland werebetter than other wetland units, the kVvalues were1.248,1.047; the correlationcoefficient R values were0.917,0.896.(7) The decontamination effect of emergent plants pond was significantly lowerthan that of subsurface flow constructed wetland and vertical flow constructed wetland,But its action is similar to the biological pond, and the general decontamination effect issuperior than the biological pond.