Study On The Process Combined With Bio-Ecological Technology For Rural Sewage Treatment

Based on the characteristics and discharge standard of rural sewage , we designed a treatment device with anaerobic,water-dropping aerating bio-contact oxidation process and constructed wetlands.The dissertation investigates the process building up the device of experiment optimal processes, the effects of the removal on nitrogen and phosphorus in constructed wetland, and the effects of the removal of the combined process on some kinds of contaminations, includes the detailed descriptions on the following subjects:1. The processes of contact biofilm are experimentally studied, including: the removal effects of filling and their density on contaminations, and some important affecting factors of water-dropping aerating, such as the height of water-dropping, the shape of water-dropping baffle and the water load. By analyzing the experimental results, optimal processes are chosen.2. By analyzing the experimental results in constructed wetland in five months, the laws of change of the nitrogen in the direction of flow and the the effluent TP. In addition, the laws show the interaction of gypsum and Phosphorus in sewage. The dissertation gives some suggestions to improve the performance of constructed wetland according to the laws.3. The effects of the removal of the combined process on some kinds of contaminations are experimentally studied. The device is be continuously monitored , and the effects of the removal of the combined process on COD,TP and TN are be analyzed according to the results. This device presented good removal rate of contamination during operation period, the average removal ratio is 60.4%,73.5%,83.1%,the average concentration of COD,TN,TP was 37.88 mg/L,5.28 mg/L,0.36 mg/L, all these index were in acccord with the pollutant discharging standard.Finally, experiments demonstrate that the process combined with methane generating pit,water-dropping aerating contact biofilm and combined flow wetlands, which treat rural wastewater, is a new process, by using this process, high benefit and low cost can be got.