【摘要】 以SBR成功富集后的反硝化聚磷菌（DPBs）为研究对象,分别考察了污泥龄（SRT,35、25、15 d）及pH值（7. 5、8. 0、8. 5）对反硝化除磷过程的影响.结果表明,SRT从35d缩短至25d,使活性污泥浓度（MLVSS）从2 821 mg·L^-1降低为2 301mg·L^-1,而污泥负荷（F/M,以COD/MLVSS计）从0. 256 kg·（kg·d）^-1增加至0. 312 kg·（kg·d）^-1,虽然净释磷量及净吸磷量有所下降,但是由于污泥活性的增加,此阶段厌氧释磷、缺氧吸磷及比反硝化速率均达到最高,分别为25. 07、15. 92及9. 45mg·（g·h）^-1,污泥含磷率从4. 78%升为5. 33%,出水PO₄^3--P浓度保持在0. 5 mg·L^-1以下,即PO₄^3--P去除率稳定在95%以上;当SRT进一步缩短为15d时,MLVSS低至1448 mg·L^-1,污泥中DPBs占聚磷菌（PAOs）的比例从82. 4%骤降为65. 7%,表明过短的SRT使得DPBs逐渐从系统中流失,此阶段污泥含磷率降至3. 43%,释磷、吸磷及比反硝化速率亦出现不同程度的降低.随着pH值的升高（7. 5～8. 0）,厌氧释磷及缺氧吸磷速率也升高,pH值为8. 0时分别达到25. 86 mg·（g·h）^-1和16. 62 mg·（g·h）^-1;当pH超过8. 0后,除磷效率快速下降,推测为磷化学沉淀导致.更多还原

【Abstract】 In this work,the effects of the sludge retention time（ SRT,35,25,or 15 d） and pH（ 7. 5,8. 0,8. 5） on denitrifying phosphorus removal were investigated using denitrifying phosphorus bacteria（ DPBs） enriched in a sequencing batch reactor（ SBR）.The results indicated that shortening the SRT from 35 d to 25 d resulted in a decrease in the mixed liquor volatile suspended solids（ MLVSS） from 2 821 to 2 301 mg·L^-1,while the sludge loading rate（ F/M） increased from 0. 256 kg·（ kg·d）^-1 to 0. 312 kg·（ kg·d）^-1. Although the quantity of net phosphorus release and net phosphorus uptake decreased at this stage,the rates of anaerobic phosphorus release,anoxic phosphorus absorption,and denitrification reached their highest levels with values of 25. 07,15. 92,and 9. 45 mg·（ g·h）^-1,respectively,due to the increased sludge activity. Consequently,the phosphorus content of the sludge increased from 4. 78% to 5. 33%,and the removal rate of PO₄^3--P was stable at above 95% with an average effluent PO₄^3--P concentration below 0. 5 mg·L^-1. When the SRT was further shortened to 15 d,the MLVSS decreased to values as low as 1 448 mg·L^-1,and the proportion of DPBs in the phosphorus accumulating organisms（ PAOs） decreased from 82. 4% to 65. 7%,indicating that the DPBs were gradually washed out from the system due to the excessively short SRT. At this stage,the phosphorus content of sludge decreased to 3. 43%,while the rates of phosphorus release,phosphorus absorption,and denitrification also decreased to some extent. When the pH was increased（ 7. 5-8. 0）,the anaerobic phosphorus release rate and the anoxic phosphorus absorption rate also increased,and reached 25. 86 mg·（ g·h）^-1 and 16. 62 mg·（ g·h）^-1,respectively,at a pH of 8. 0. When the pH exceeded 8. 0,the phosphorus removal efficiency dropped rapidly,supposedly due to phosphorus chemical precipitation.更多还原