化工学报Issue(12)：4985-4996,12.DOI:10.3969/j.issn.0438-1157.2014.12.046
长泥龄改良A2/O工艺的短程硝化反硝化除磷
Shortcut nitrification and denitrifying phosphorus removal in improved A2/O technique with long SRT
摘要
Abstract
Aiming at solving the contradiction of sludge retention time (SRT) between nitrification and dephosphorization, and enhancing the simultaneous nitrogen (N) and phosphorus (P) removal efficiency of the low C/N (P) ratio domestic sewage in the traditional A2/O process, an improved A2/O technique with long SRT was developed. The novel process could select and strengthen the activated sludge, and enrich the denitrifying phosphorus accumulating organisms (DPAO) with long SRT effectively. After washing out nitrite oxidizing bacteria (NOB), the reactor ran under the condition of SRT=19.6 d, and sludge concentration (MLSS)=5.5 g·L−1, hydraulic retention time (HRT)=8.2 h, sludge return ratio (R)=90%, nitrated liquid reflux ratio (r)=250%, dissolved oxygen (DO)=1.5—0.3 mg·L−1 for the A2/O zone. HRT=4 h, aeration cycle was 1 h, aeration time was 1 min (DO=0.3—0.5 mg·L−1) and settling time was 59 min for the intermittent aeration zone. Average removal rate of COD, NH+4-N, TP and TN reached 88.71%, 99.2%, 93.77% and 89.52% respectively, nitrosation rate (NO−2-N/NO−x-N) was up to 97.2%, and DPAO/PAO ratio in sludge was 95.5%, and the final effluent met the first class level A of the GB 18918—2002 standard. It was found that about 72.96% of COD in sewage was utilized by DPAO for PHA production to accumulate P, 15.75% of COD was consumed by heterotrophic denitrifying bacteria, and about 41.96% and 31.31% of N were wiped off through phosphorus removal and heterotrophic denitrifying. The discharged sludge was mainly composed of the biomass of DPAO and denitrifying bacteria, accounting for 82.74% and 17.24% respectively. The technique could reduce 58.76% of carbon source consumption and 44.6% of sludge discharge comparing to the traditional nitrogen phosphorus removal pathway.关键词
A2/O/厌氧/需氧/废水/低C/N比/反硝化除磷/短程硝化Key words
A2/O/anaerobic/aerobic/waste water/low C/N ratio/denitrifying phosphorus removal/partial nitrification分类
资源环境引用本文复制引用
罗亚红,李冬,鲍林林,许达,蔡言安,张杰..长泥龄改良A2/O工艺的短程硝化反硝化除磷[J].化工学报,2014,(12):4985-4996,12.基金项目
国家科技重大专项水专项（2012ZX07202-005）。@@@@supported by the National Water Pollution Control and Management Technology Major Projects (2012ZX07202-005) （2012ZX07202-005）
