Study Of Constructed Wetland Application In Cold Area

Constructed wetland is a recently developed technology of wastewater treatment.There are many advantages of this technology: high removal capacity, simpleconstruction, low investment costs, low maintenance and operation costs, simpleoperation and maintenance. which is adapted to sewage treatment of village and smalltown absent of capital and techniciano However, the current constructed wetlands have low hydraulic loading rate, low nitrogen and phosphorus removal efficiency, and occupylarge ground area. The aim of this paper is to look for optimal hydraulic loading rates, simple operation and maintenance, and good substrate of constructed wetland to solutethe above problems.This paper analyzed definition,character,sort,function of constructed wetland by consulting foreign and national documents. And we discussed domestic and overseas actuality and expectation of about constructed wetland.We made a experiment for subsurface constructed wetland. We chose stuffing material,stuffing thickness and wetland plants as technique parameter and researched its' effect to purifying efficiency of constructed wetland and resulted the best technique parameter. Then we used this experiment to project and researched efficiency of subsurface constructed wetland. We introduced the design and conformation of subsurface constructed wetland building in cold area, and analyzed the data of pollutant in sewage such as COD, B0D5, TN and TP to validate feasibility of application of constructed wetland in cold area. And article advanced some ameliorated measure to extend constructed wetland building.After adding heat preservation and measuring annual water quality, we confirmed the sewage treatment efficiency of constructed wetland built in cold area in winter.According to the analysis of experiment and project discussed above, it concluded that: Locale datum measured in completed project showed that constructed wetland can be used to treat sewage in winter and technique of sewage treatment of constructed wetland is feasible in cold area. Stuffing makeup and ratio are the key of constructed wetland running chronically,stably and treating sewage reaching water quality. We can improve removal efficiency of BOD of constructed wetland in cold area and ability of treating sewage in cold area by design proper superstratum.