生物脱氮除磷工艺的现状与发展

为遏制水体的富营养化,氮、磷的排放标准日趋严格,生物脱氮除磷工艺能有效地去除水体中的氮、磷.文中介绍了生物脱氮除磷的传统工艺和新发展的工艺,并认为今后应对生物脱氮除磷机理加以深人的研究,并对今后的发展趋势作了展望.     

城市污水脱氮除磷结合工艺评述

城市污水脱氮除磷结合工艺是一种重要的水污染控制技术,根据脱氮与除磷机理之间的冲突,比较分析了目前主流的脱氮除磷结合工艺的优缺点,同时提出了一些建议.     

人工湿地脱氮除磷特性研究

针对流域水体富营养化加剧和二级处理水氮磷指标较高的问题,提出以人工湿地对二级出水继续低耗、理想地脱氮除磷。研究中通过对照不同进水水质条件下,不同结构人工湿地的脱氮除磷效能,探讨了人工湿地内的主要脱氮除磷途径。研究表明,表面流湿地内植物对氨氮吸收／吸附和硝化过程为主要氮转化途径,潜流湿地内直接反硝化过程为主要脱氮途径,脱氮效率30％～40％;磷在人工湿地内主要依赖除磷填料床的物化吸附、共沉淀去除,除磷效率达80％以上。     

改进型双泥反硝化除磷脱氮工艺 --一种可望从根本上解决脱氮除磷矛盾的新工艺

在对单污泥系统同时脱氮除磷内在矛盾分析的基础上,探讨了目前国内外双泥系统优化脱氮除磷的可行性,提出了强化解决氮磷矛盾的新工艺——改进型双泥反硝化除磷脱氮工艺。本研究利用SBR反应器对改进型工艺进行了实验室模拟,并为该系统的进一步完善提出了建议。     

浅论生物除磷脱氮的机理及工艺

对污水生物法除磷脱氮的机理作了简要分析，并介绍了几种高效、经济、实用的生物除磷脱氮工艺。     

改良A2/O工艺的工程实践

城市污水处理厂采用多点进水的改良A2/O生物脱氮除磷工艺,取得了较好的脱氮除磷效果.在工艺运行中,通过采取有效的调控措施,保证了生化池脱氮除磷各反应单元的溶解氧要求,得到了较佳的工艺运行参数控制范围.     

城市污水生物脱磷除氮工艺的新进展

阐述了生物除磷和反硝化脱氮的机理，由此引出脱氮除磷在基质竞争和泥龄方面的矛盾，提出了解决该矛盾的两种可行方案：针对方案，着重介绍了目前脱氮除磷工艺的新进展。     

改良A^2/O工艺的工程实践

城市污水处理厂采用多点进水的改良A^2/O生物脱氮除磷工艺,取得了较好的脱氮除磷效果.在工艺运行中,通过采取有效的调控措施,保证了生化池脱氮除磷各反应单元的溶解氧要求,得到了较佳的工艺运行参数控制范围.     

生物脱氮除磷工艺的研究进展

为遏制水体富营养化的恶化，氮，磷的排放标准日趋严格，生脱氮除磷工艺能有效地去除水体中的氮、磷。通过对现有的生物脱氮除磷传统工艺和新近发展工艺的介绍和分析，指出经济、高效、低能耗是其发展的方向，同时认为今后应加强对生物脱氮除磷机理更深入的研究，大力开发技术成熟，高效经济又符合我国国情的新工艺。     

城镇污水AAOA高标准除磷脱氮技术开发与应用

针对城镇污水在高标准除磷脱氮过程中碳源不足的问题,提出了基于多路径协同的AAOA除磷脱氮技术,探究了 AAOA系统实现高标准除磷脱氮对进水C/N的要求,并对实际城镇污水处理进行了实验研究.结果表明:当进水C/N分别为6、7.5、9时,系统TN去除率分别为74.12％、84.90％、90.05％,TP去除率分别为48.2...     

双泥膜法SBR脱氮除磷效果研究

通过实验室小试，以人工模拟生活污水为研究对象，考察了基于反硝化除磷理论开发的双泥膜法SBR工艺的脱氮除磷效果。长期试验结果表明：双泥膜法SBR工艺能使硝化菌和除磷菌各自在最佳的环境中生长，解决了传统工艺中脱氮和除磷的矛盾，节省了碳源和能源，并取得了稳定高效的脱氮除磷效果。在进水C∶N∶P为25∶5∶1，换液比为75%的情况下，系统对COD，TP和NH⁺₄-N的平均去除率分别为89.13%、96.12%和86.78%。     

CAS-BT复合反应器同步脱氮除磷试验研究

在CAST反应器中引入自制悬浮填料,构成了CAS-BT复合反应器,采用人工配制废水,对其同步脱氮除磷效果进行了试验研究.试验结果表明,当TN为178.05 mg/L、TP为28.32 mg/L时,CAS-BT工艺取得了很好的同步脱氮除磷效果,TN和TP的去除率分别达到97.55%和98.10%.进行同步脱氮除磷时,CAS-BT比其他的水处理工艺更具优势.     

污泥回流比对厌氧/好氧工艺除磷效果影响的研究

以长距离输送的合流制污水为进水,考察不同污泥回流比下厌氧/好氧(A/O)工艺对COD、N、P的去除效果,深入研究污泥回流比对生物除P代谢过程的影响.结果表明,污泥回流比对COD及NH+4-N的去除没有明显影响,但对TN、TP、PO3-4-P的去除影响较大.随着污泥回流比的增大,聚磷菌(PAO)的厌氧释P量逐渐减小,P的去除率逐渐降低.减小污泥回流比,可延长A/O工艺厌氧池实际HRT,增加PAO在厌氧池可有效利用的碳源,使PAO在厌氧池充分释P,从而提高除P效率.     

Understanding the granulation process of activated sludge in a biological phosphorus removal sequencing batch reactor

The granulation of activated sludge was investigated using two parallel sequencing batch reactors (SBRs) operated in biological nitrogen and phosphorus removal conditions though the reactor configuration and operating parameters did not favor the granulation. Granules were not observed when the SBR was operated in biological nitrogen removal period for 30 d. However, aerobic granules were formed naturally without the increase of aeration intensity when enhanced biological phosphorus removal (EBPR) was achieved. It can be detected that plenty of positive charged particles were formed with the release of phosphorus during the anaerobic period of EBPR. The size of the particles was about 5-20 μm and their highest positive ζ potential was about 73 mV. These positive charged particles can stimulate the granulation. Based on the experimental results, a hypothesis was proposed to interpret the granulation process of activated sludge in the EBPR process in SBR. Dense and compact subgranules were formed stimulated by the positive charged particles. The subgranules grew gradually by collision, adhesion and attached growth of bacteria. Finally, the extrusion and shear of hydrodynamic shear force would help the maturation of granules. Aerobic granular SBR showed excellent biological phosphorus removal ability. The average phosphorus removal efficiency was over 95% and the phosphorus in the effluent was below 0.50 mg L⁻¹ during the operation.     

Toward a high-rate enhanced biological phosphorus removal process in a membrane-assisted bioreactor.

A membrane enhanced biological phosphorus removal (MEBPR) process was studied to determine the impact of hydraulic retention time (HRT) and solids retention time (SRT) on the removal of chemical oxygen demand (COD), nitrogen, and phosphorus from municipal wastewater. The MEBPR process was capable of delivering complete nitrification independent of the prevailing operating conditions, whereas a significant improvement in COD removal efficiency was observed at longer SRTs. In the absence of carbon-limiting conditions, the MEBPR process was able to achieve low phosphorus concentrations in the effluent at increasingly higher hydraulic loads, with the lowest HRT being 5 hours. The MEBPR process was also able to maintain optimal phosphorus removal when the SRT was increased from 12 to 20 days. However, at higher suspended solids concentrations, a substantial increase was observed in carbon utilization per unit mass of phosphorus removed from the influent. These results offer critical insights to the application of membrane technology for biological nutrient removal systems.     

Taking advantage of aerated-anoxic operation in a full-scale University of Cape Town process.

To evaluate the potential benefits or limitations of aeratedanoxic operation in high-rate biological nutrient removal processes, we conducted a full-scale experiment in a University of Cape Town (UCT)-type wastewater treatment plant by reducing oxygen supply and increasing flowrates within one treatment train so that aerated-anoxic conditions (i.e., zones that receive oxygen but maintain dissolved oxygen concentrations below 0.5 mg/L) could be implemented in a section of the aerated zone. With this retrofitted configuration, total nitrogen removal increased from 54 to 65%, but was limited by the organic carbon available for denitrification. Furthermore, the significant reduction in dissolved oxygen concentrations in the aerated zone did not negatively affect enhanced biological phosphorus removal, demonstrating that the implementation of an aerated-anoxic zone within a UCT-type reactor can contribute to a reduction in operational costs and a slight improvement in total nitrogen removal, without compromising the extent of phosphorus removal.     

低曝气下PAC强化SBR工艺同步脱氮除磷

采用序批式反应器(SBR)处理模拟生活污水,研究不同曝气量(30、24、18和12 L/h)下活性污泥同步脱氮除磷规律,并在最佳曝气量下,比较了粉末活性炭-序批式反应器(PAC-SBR)和SBR的脱氮除磷效率,分析了低曝气下PAC-SBR的运行特性和优越性。实验结果表明,当曝气量为24 L/h时,SBR内出水效果较好,其COD、TN和TP的平均去除率分别可以达到90.02%、81.13%和88.12%。在这个最佳曝气量下,PAC-SBR具有明显的优势,其COD、TN和TP的平均去除率均高于SBR,并且PAC-SBR具有较好的污泥沉降性能和较高的活性污泥浓度。在PAC-SBR中,活性污泥以PAC作为微生物载体强化了生物降解效果,并改善了低曝气下污泥絮体的结构,促使反应器内先后形成缺氧-厌氧-微氧/缺氧-缺氧的环境,利于同步硝化反硝化和反硝化聚磷,提高了PAC-SBR的同步脱氮除磷效率。     

A-A2/O工艺脱氮实践运行效果及优化

A-A²/O工艺是预缺氧/厌氧/缺氧/好氧组成的生物脱氮除磷工艺，广州市某污水处理厂采用该工艺处理城市污水，具有同时去除有机物、脱氮除磷能力，但是TN去除率较低。分析了其TN去除率低的原因，并提出相应措施。该水厂针对本厂水质特征以及影响工艺脱氮性能的主要因素，优化了工艺控制参数，提高了TN去除率和TN达标保证率。     

A-A~2/O工艺脱氮实践运行效果及优化

A-A2/O工艺是预缺氧/厌氧/缺氧/好氧组成的生物脱氮除磷工艺,广州市某污水处理厂采用该工艺处理城市污水,具有同时去除有机物、脱氮除磷能力,但是TN去除率较低。分析了其TN去除率低的原因,并提出相应措施。该水厂针对本厂水质特征以及影响工艺脱氮性能的主要因素,优化了工艺控制参数,提高了TN去除率和TN达标保证率。     

Evaluation of membrane bioreactor process capabilities to meet stringent effluent nutrient discharge requirements.

A six-stage membrane bioreactor (MBR) pilot plant was operated to determine and demonstrate the capability of this process to produce a low-nutrient effluent, consistent with the nutrient reduction goals for the Chesapeake Bay. Biological nitrogen removal was accomplished using a multistage configuration with an initial anoxic zone (using the carbon in the influent wastewater), an aerobic zone (where nitrification occurred), a downstream anoxic zone (where methanol was added as a carbon source), and the aerated submerged membrane zone. The capability to reliably reduce effluent total nitrogen to less than 3 mg/L as nitrogen (N) was demonstrated. A combination of biological (using an initial anaerobic zone) and chemical (using alum) phosphorus removal was used to achieve effluent total phosphate concentrations reliably less than 0.1 mg/L as phosphorus (P) and as low as 0.03 mg/L as P. Alum addition also appeared to enhance the filtration characteristics of the MBR sludge and to reduce membrane fouling. Aeration of the submerged membranes results in thickened sludge with a high dissolved oxygen concentration (approaching saturation), which can be recycled to the main aeration zone rather than to an anoxic or anaerobic zone to optimize biological nutrient removal. Biological nutrient removal was characterized using the International Water Association Activated Sludge Model No. 2d. The stoichiometry of chemical phosphorus removal was also consistent with conventional theory and experience. The characteristics of the solids produced in the MBR were compared with those of a parallel full-scale conventional biological nitrogen removal process and were generally found to be similar. These results provide valuable insight to the design and operating characteristics of MBRs intended to produce effluents with very low nutrient concentrations.