Study On The Full-Scale Trial With CASS Process In Qunli Wastewater Treatment Plant

With growing awareness of environmental protection, environmental protection, voice rising, the increasingly serious water pollution situation would inevitably lead to people's attention, increasing the intensity of water pollution control. As the land has become tighter and the increasingly stringent requirements of nitrogen and phosphorus removal, covers an area of provincial, nitrogen and phosphorus removal process a good CASS sewage wastewater treatment in the city to get a wide range of applications.CASS process in order to further promote the city sewage waste water treatment applications, the research is based on comprehensive improvement of Harbin Engineering Hejiagou important part of the group of the engineering force of sewage treatment plants as test object. Subjects activated sludge from the sewage treatment plant cultivation and domestication process of commissioning, trial run to the official running a series of research and study and study the key factors affecting the start of the CASS process, commissioning and operation of the impact.By inoculation of culture, after thirty days to complete the activated sludge acclimation, CASS into the commissioning process, the effluent COD mean removal rate of 76.9%, TP effluent standards, and the average removal rate of NH₃-N was only 41.4%, and the effluent were not standard, the mean reached 26.03mg/L. Thus, during the commissioning phase will focus on nitrogen removal system for debugging. Because the influent organic load fluctuations, coupled with winter water temperature is too low, nitrogen removal system until the end of 2011, three successful commissioning, thus, into the trial operation of wastewater treatment plant stage. 30 days after the trial run at full capacity, the effluent COD, BOD5, NH₃-N, TN, SS, TP average was 51.2mg/L, 14mg/L, 7.11mg/L, 18.62mg/L, 20mg/L, 0.66mg/L, wastewater treatment plant effluent quality and stability, to meet the design standards.Wastewater treatment plant in order to determine reasonable operating conditions, the present study, the effect of CASS Process aeration time and the drainage of more than two factors were studied. 3h and 4h with aeration time, COD, NH₃-N, TN, TP, the average removal rate was 89.7%, 83.3%, 60.36%, 91.5% and 88.0%, 91.0%, 63.7%, 91.8%; with 1/3 and 1/4 drain when the ratio of operating conditions, COD, NH₃-N, SS, TP, the average removal efficiency was 86.3%, 84.9%, 91.8%, 89.1% and 88.5%, 87.1% 93.2%, 90.9%. Longer aeration time and the smaller drainage is better than the sewage treatment, aeration time in the 3h and 1/3 of operating conditions than the drainage conditions, water quality and stability standards, and therefore, the use of 1/3 of the drainage 3h aeration time ratio and is more reasonable. Determine the water 1h, aeration 3h, 1h, and precipitation 1h decanter idle more reasonable as sewage treatment plants operating cycle.