共查询到19条相似文献,搜索用时 93 毫秒
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污泥运行指标对A/A/O氧化沟生物脱氮的影响研究 总被引:1,自引:0,他引:1
采用实际城市污水,研究污泥回流比、污泥龄和污泥浓度(MLSS)对中试A/A/O氧化沟脱氮的影响。结果表明:系统脱氮能力随污泥回流比增大而增强,大于90%时,NH4+-N和TN去除率没有明显提高,还会增加能耗。污泥回流比为60%~90%,泥龄为15~20 d时脱氮效果较好,还需根据进水负荷和脱氮效果进行调节。MLSS对工艺同时硝化反硝化(SND)有显著影响,当MLSS从3 000 mg/L增至6 000 mg/L时,NH4+-N去除率从81.7%增至98.8%,TN去除率从47.2%增至66%,SND/TN从19.8%增至37.4%。 相似文献
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采用A/A/O氧化沟反应器处理低碳源城市污水,考察了DO浓度对硝化及反硝化过程的影响,分析DO浓度与同步硝化反硝化(SND)脱氮反应速率的关联性。研究发现,较适宜的DO浓度范围为1.0~1.5 mg/L,DO浓度降低会影响氨氮降解,硝化效果急剧变坏的临界溶解氧浓度范围为0.8~1.5 mg/L,而DO浓度过高则不利于主反应区SND脱氮,同时较多的溶解氧内回流至缺氧区会破坏其脱氮环境。当DO<2.0 mg/L时,NO-3-N生成速率与NH+4-N氧化速率之比与DO之间线性关系较好;SND随着DO浓度的升高而受到抑制,当DO>2.0 mg/L时,NO-3-N生成速率与NH+4-N氧化速率之比与DO之间基本不呈线性关系,系统中基本不发生SND反应。 相似文献
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采用人工配水,通过控制进水p H值为7.5~8.2、DO为0.4~0.7 mg/L、污泥龄9~13天等实验条件,经过两个阶段共46d的驯化培养,在厌氧/好氧/缺氧(A/O/A)SBR反应器内实现短程同步硝化反硝化与除磷过程的耦合。系统稳定运行后,对一个典型周期内水质的变化情况进行了测定和分析,系统对COD、NH+4-N、TN、TP的去除率分别为94.8%、97.6%、89.4%、93.1%。在此基础上,探讨了不同进水p H、不同曝气量对系统运行稳定性的影响。结果表明:随着p H的改变,系统对去除氮、磷的稳定性呈现不同的变化趋势;而过高的曝气量,会造成系统内的短程硝化向全程硝化转变。 相似文献
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介绍了A/O法生物脱氮工艺的特点,分析了焦化废水处理过程中进水水质、废水温度、溶解氧和pH值等对A/O生物脱氮工艺的影响。经生产调试和优化操作,系统运行稳定,各项参数指标控制在工艺要求范围内,出水酚≤0.3mg/L、氰≤0.2mg/L、COD≤50mg/L、氨氮≤8mg/L,达到国家排放标准。 相似文献
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Xin Zhou Yaxin Li Yi Zhao Xiuping Yue 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2013,88(2):305-310
BACKGROUND: Biological treatment efficiency of coking wastewater is rather poor, especially for chemical oxygen demand (COD) and ammonia‐nitrogen (NH$_{4}^{+}$ ‐N) removal due to its complex composition and high toxicity. RESULTS: A pilot‐scale anaerobic/anoxic/oxic/oxic (A2/O2) biofilm system has been developed to treat coking wastewater, focusing attention on the COD and NH$_{4}^{+}$ ‐N removal efficiencies. Operational results over 239 days showed that hydraulic retention time (HRT) of the system had a great impact on simultaneous removals of COD and NH$_{4}^{+}$ ‐N. At HRT of 116 h, total removal efficiencies of COD and NH$_{4}^{+}$ ‐N were 92.3% and 97.8%, respectively, reaching the First Grade discharge standard for coking wastewater in China. Adequate HRT, anoxic removal of refractory organics and two‐step aerobic bioreactors were considered to be effective measures to obtain satisfactory coking effluent quality using the A2/O2 biofilm system. The correlation between removal characteristics of pollutants and spatial distributions of biomass along the height of upflow bioreactors was also revealed. CONCLUSION: The study suggests that it is feasible to apply the A2/O2 biofilm process for coking wastewater treatment, achieving desirable effluent quality and steady process performance. © 2012 Society of Chemical Industry 相似文献
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膜生物反应器处理己内酰胺生产废水 总被引:2,自引:1,他引:2
为了更加有效地提高己内酰胺生产废水生化处理装置抗高浓度废水冲击能力,在原A/O处理系统中采用膜生物反应器技术对己内酰胺生产废水进行生化处理。工业应用结果表明:由于己内酰胺废水中氨氮含量较高,膜生物反应器进水pH值应该控制在8.5~9.5,以保证系统有效的硝化反应,去除氨氮;当进水COD、氨氮的质量浓度分别控制在2 000、200 mg/L以内时,出水COD、氨氮的质量浓度分别小于70、15 mg/L。处理后的水质能够达到国家一级排放标准。 相似文献
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Donal Mulkerrins Clodagh Jordan Sinead McMahon Emer Colleran 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2000,75(4):261-268
Considerable research has been performed on biological nutrient removal (BNR) systems which remove the problematic nutrients, nitrogen and phosphorus, that cause eutrophication. This research focussed on setting up two laboratory‐scale anaerobic/anoxic/oxic (A/A/O) systems and investigating their reliability while undergoing various parameter changes. Pump failure, in the first trial, R1, led to a decrease in pH, exposure of the sludge to relatively low nitrate concentrations and reduction of the suspended solids concentration within the system. This adversely affected the phosphorus removal efficiency. Shock loading the system with increased influent phosphate concentrations for 56 days was shown to aid remediation of the phosphorus removal efficiency to values between 65 and 70% (w/w). The second trial, R2, highlighted the presence of bacteria capable of P‐uptake under anoxic conditions (in the presence of nitrate). The characteristic anaerobic P‐release was also evident. The bacteria responsible for phosphate uptake under anoxic conditions are thought to be the denitrifying phosphate removing bacteria (DPB). However, the presence of higher nitrate concentrations retarded the P‐removal efficiency to some extent. Secondary release of P was evident in the clarifier of the A/A/O system during the R2 trial and especially during times of increased nitrate concentrations in the system. Between 20 and 40% (w/w) of the P taken up in the oxic stage of the system was released in the clarifier at various stages throughout the trial. © 2000 Society of Chemical Industry 相似文献
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针对传统A2/O工艺存在的泥龄矛盾,将脱氮和除磷分置于前后2套不同的A/O系统中,第一级A/O采用活性污泥法除磷;第二级A/O采用生物膜法脱氮。以生活污水为处理对象进行试验研究。结果表明,在泥龄为6 d、水温为22~28℃,进水NH3-N、TP、COD的质量浓度分别为40~70、2.0~6.0、150~320 mg/L条件下,出水NH3-N、TP、COD的平均质量浓度分别为5.9、1.0、40 mg/L,均达到了城镇污水处理厂污染物排放标准(GB18918-2002)中的一级排放标准,其去除率分别为82.5%、69.7%、83.1%。 相似文献
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In this study, the performance of a sequencing batch biofilm reactor (SBBR) for removal of nitrogen and phosphorus from swine wastewater was evaluated. The replacement rate of wastewater was set at 12.5%throughout the exper-iment. The anaerobic and aerobic times were 3 h and 7 h, respectively, and the dissolved oxygen concentration of the aerobic phase was about 3.95 mg·L?1. The SBBR process demonstrated good performance in treating swine wastewater. The percentage removal of total chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), total nitrogen (TN), and total phosphorus (TP) was 98.2%, 95.7%, 95.6%, and 96.2%at effluent concentrations of COD 85.6 mg·L?1, NH4+-N 35.22 mg·L?1, TN 44.64 mg·L?1, and TP 1.13 mg·L?1, respectively. Simultaneous nitrification and denitrification phenomenon was observed. Further improvement in removal efficiency of NH4+-N and TN occurred at COD/TN ratio of 11:1, with effluent concentrations at NH4+-N 18.5 mg·L?1 and TN 34 mg·L?1, while no such improvement in COD and TP removal was found. Microbial electron microscopy analysis showed that the fil er surface was covered with a thick biofilm, forming an anaerobic–aerobic microenvironment and facilitating the removal of nitrogen, phosphorus and organic matters. A long-term experiment (15 weeks) showed that stable removal efficiency for N and P could be achieved in the SBBR system. 相似文献
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Elena Rustrian Jean Philippe Delgens Nicolas Bernet Ren Moletta 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1998,73(4):421-431
The objective of this study was to develop an integrated process for simultaneous removal of carbon, nitrogen and phosphorus from industrial wastewaters. The process consisted of a-two step anaerobic digestion reactor, for carbon removal, coupled with a sequencing batch reactor (SBR) for nutrient removal. In the proposed process, carbon is eliminated into biogas by anaerobic digestion: acidogenesis and methanogenesis. The volatile fatty acids (VFA) produced during the first step of anaerobic digestion can be used as electron donors for both dephosphatation and denitrification. In the third reactor (SBR) dephosphatation and nitrification are induced through the application of an anaerobic–aerobic cycle. This paper describes the first trials and experiments on the SBR and a period of 210 days during which the SBR was connected to the acidogenic and methanogenic reactors. It was shown that nitrification of ammonia took place in the SBR reactor, during the aerobic phase. Furthermore, denitrification and VFA production were achieved together in the acidogenic reactor, when the efflux of nitrates from the SBR reactor was added to the first reactor influx. The proposed process was fed with a synthetic industrial wastewater, the composition of which was: total organic carbon (TOC)=2200 mg dm−3, total Kjeldahl nitrogen (TKN)=86 mg dm−3, phosphorus under phosphate form (P-PO4)=20 mg dm−3. In these conditions, removals of carbon, nitrogen and phosphorus were 98%, 78% and 95% respectively. The results show that the combination of the two-step anaerobic digestion reactor and an SBR reactor is effective for simultaneous carbon, nitrogen and phosphorus removal. Reactor arrangements enabled zones of bacterial populations to exist. Complete denitrification occurred in the acidogenic reactor and hence the anaerobic activity was not reduced or inhibited by the presence of nitrate, thus allowing high TOC removal. Stable phosphorus release and phosphorus uptake took place in the SBR after coupling of the three reactors. A fast-settling compact sludge was generated in the SBR with the operational conditions applied, thus giving good separation of supernatant fluid. The benefits from this process are the saving of (i) an external carbon source for denitrification and phosphorus removal, (ii) a reactor for the denitrification step. © 1998 Society of Chemical Industry 相似文献