Study On The Technical Testing And Operation Of Orbal Oxidation Ditch In Small Town

With social and economic continuous development, water environment has become a current problem amony many environmental pollution problems in the world. Urban sewage discharge without meeting the standard is the main source of water pollution in numerous rivers, lakes. Strengthening discharge standards of sewage water in urban and rural areas is the fundamental solution to environmental degradation. Increasing regional wastewater treatment plant construction, meanwhile, research on progress of water technology in wastewater treatment plants is not dispensable.The main content of this topic is about running debugging of Orbal oxidation ditch in the wastewater treatment plant in Hainan Province. Orbal oxidation ditch influencing factors during the operation, as well as nitrogen and phosphorus removal in Orbal principle of oxidation ditch were introduced. This sewage treatment plant influent raw water quality, sewage treatment process, the oxidation ditch process and Orbal commissioning and operation of methods based on the actual experience of the commissioning process were present detailly. The operational control points of biological nitrogen and phosphorus removal in Orbal oxidation ditch process was explained either.During the commissioning and operation of the process of Orbal Oxidation Ditch in the sewage treatment plant, the concentration and distribution of sludge mixture and dissolved oxygen of the channel was an important control parameter. In the case of low load water, sludge microbial growth was relatively slow, when the debugging time lasted over two months, during which the pollutant removal were gradually improved. The late commissioning of the indicators pollutants were stable under requirements of water GB18918-2002 Grade B. The results showed that, the pollutant removal rate was still high in Orbal oxidation ditch with the low load condition; the COD, SS, ammonia nitrogen TN, TP removal rates were 82.9%, respectively, 81.9%, 69.1%, 66.9 % and 72.8%. In the case of influent concentration increased volatility, the water quality kept stable, indicating that oxidation ditch resistance to shock load ability. Among processing units, the anaerobic tank removed most organic matter and denitrification and phosphorus release reaction occurred, which played a good complement in oxidation ditch process. But TN removal was less effective, through analysis, the dissolved oxygen oxidation in ditch outside the ditch changed between the 1.35~2.36 mg/L. The high level of dissolved oxygen in the hypoxic environment maked the outer ditch not ideal; simultaneous nitrification and denitrification decreased. Adjusting the transfer station with the disc number and frequency of dissolved oxygen concentration in the outside aeration ditch, the effects of nitrogen and phosphorus removal made sure, according to operating conditions to ensure.The phenomenonof black sludge and sludge decay in the commissioning was caused by low dissolved oxygen concentration in early slow microbial growth, which could be resolved by increasing the amount of aeration and sludge discharge. Economic analysis showed that during the operation, the cost was 0.61 yuan per ton, which was slightly higher than normal operating costs.Based on the sewage treatment plant, the study of Orbal oxidation ditch process of debugging and commissioning after the actual processing performance can be useful for the normal operation to provide technical support and theoretical basis.