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With the promulgation of the urban sewage treatment plant pollutant discharge standards \At present, many of our sewage treatment plant for low carbon and nitrogen than poor urban sewage phosphorus removal, the effluent TP can not reach sewage discharge an A standard, there is an urgent need technical upgrading. In the traditional process, generally using a single-sludge system, the microorganisms was suspended mixed growth. Biological nutrient removal process nitrifying bacteria and phosphorus accumulating bacteria coexist on the same activated sludge system, two generations of difference, both in activity in the best condition is difficult to ensure through the mud Control SRT , leading to the presence of some of the drawbacks, such as nitrification is not ideal, phosphorus removal, sludge settling deterioration. In this paper, a two-sludge system based on biological aerated filter nitrification start, run, and sludge characteristics. A run cycle 7.5h after 20d of anaerobic / aerobic training aerobic phosphate accumulating bacteria were dominant; anaerobic / anoxic culture 27d dominant strain of denitrifying phosphorus removal bacteria activity sludge. Studies have shown that: (1) removal of major pollutants, the system has reached a high level, up to about 90% of the total phosphorus removal, COD removal rate was about 89%, ammonia removal efficiency of up to about 73% water, almost not monitoring nitrate and nitrite. After the final process improvement, major pollutants in the final effluent have reached an A standard GB18918-2002. (2) denitrifying phosphorus removal bacteria stable performance, increased with the increase of pH phosphorus release; increasing temperature increase in the amount of phosphorus release, but should not be too high, the best temperature is about 30 degrees; acetic acid anaerobic phosphorus release the biggest role, followed by glucose, ethanol, methanol; NO3-existence of denitrifying phosphorus removal bacteria anaerobic phosphorus release inhibition will occur only when its denitrification anaerobic phosphorus release; appropriate improve the organic load of sludge help to improve the amount of phosphorus release, but not too large, the ultimate organic load 0.12gCOD/gMLSS, beyond this range continues to increase organic load to increase the amount of phosphorus release a negligible role. (3) the more traditional obligate aerobic phosphorus the bacteria removal process, denitrifying phosphorus removal bacteria can save about 50% and 30% of the COD and oxygen consumption, 50% of the corresponding reduction in the amount of excess sludge. Relative to the traditional craft with a carbon dual-use \Efficient phosphorus removal, effluent phosphorus concentration to achieve an A standard.
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