Application Research On Domestic Sewage Treatment By PKA Constructed Wetland

This paper studies on the application of matrix composite constructed wetland, monitoring three different matrix composite constructed wetlands with different plants, different substrates and different configurations for about one year, and investigating different types of constructed wetlands' polluted water purifying effect, influencing factors and removal mechanism of pollutants,contaminants to be detected are mainly CODcr, NH3-N, TP and BOD5. In order to understand matrix composite artificial wetland technology operating rules and mechanisms to deal with pollution in the water, select the appropriate matrix, providing the initial operating parameters matrix composite artificial wetland technology in wastewater treatment. Then this is a reference of the PKA constructed wetland in the sewage treatment and water restoration.After the constructed wetlands are stable, according to “Surface Water Environment Quality Standard”(GB3838-2002), detect and analyze the three wetlands' inlet and outlet water, and then category the water in accordance with the amount of the pollutants in the water.Summarize three wetland pollutant removal as follows:1. The three constructed wetlands on CODcr removal rate between 74.3%-91.6%, NH3-N removal rate is between 83.1%-98.1%, in the case of TP removal lowest was 77.8%, the highest 97%, BOD5 removal rate of between 77.7%-96.6%, removal of contaminants are substantially above 80%, and even some more than 90%, indicating,generally speaking, a high matrix composite artificial wetland sewage treatment rate is better than the ordinary constructed wetland.2. Although the three constructed wetlands have different pollutant removal capacity,but in fact the bigger difference results from the season. As the seasons change, the removal of pollutants is very different. And without exception, three constructed wetlands' pollutants removal rates from highest to lowest are summer,autumn,spring and winter. Wherein BOD5 most affected by seasonal changes.3. After comprehensive comparison of contaminant removal efficiency, the dielectric layer laying and other standards, the first constructed wetland has highest removal rate, longest utility time, so it can save money, with more economic benefits. Therefore, it's the best example for promotion.The results show that matrix composite constructed wetland technology is relatively good sewage treatment technology. Although the removal efficiency of pollutants reduces in winter and spring, it remains above 70%. Finally, combining the three constructed wetland pollutant removal and outlet water quality, the matrix proportion plan of the first one is most prominent. Therefore, in similar circumstances, the first one can be a sample to promote.