试论污水生物除磷脱氮技术

本文论述了磷、氮与富营养化的关系并介绍了几种除磷脱氮工艺。各种除磷脱氮工艺的特点各异,适应于不同的条件。对于寒冷地区,进水BOD_5浓度较低条件下进行生物除磷,采用Phostrip工艺是较为适宜的。     

表面流人工湿地中氮磷的去除机理

人工湿地作为一种高效、低耗的污水处理新工艺已被广泛接受，特别是其在脱氮、除磷方面的应用逐步为人们所重视。本文深入地讨论了表面流人工湿地中各种生物、物理、化学过程对污水中各种形态含氮、含磷化合物的去除机理，及其具体途径、相关反应和反应类型，总结了国内外对各个过程影响因素、控制条件、反应速度、去除能力及相互之间协调拮抗作用的研究结果。虽然硝化／反硝化作用和土壤吸附沉淀作用已被公认为是表面流人工湿地脱氮、除磷的主要途径，但不同研究结果之间仍存在着明显差异，鲜有多介质环境条件下各种脱氮、除磷过程中多种氮、磷形态的质量平衡研究，而以此为基础的人工湿地生态动力学模型的研究则是深入了解人工湿地运行机理、设计和预测其处理效率，以及推动人工湿地污水处理工艺广泛应用的关键。     

实时控制技术在污水生物处理中的研究进展

针对目前污水处理厂采用固定时间控制策略所暴露出的问题，从污水生物处理反应机理上分析了溶解氮（DO），氧化还原电位（ORP）和pH值作为污水生物处理实时控制参数的可行性，得出污水处理过程中反应器内DO，ORP和pH的变化可以间接反应有机物降解和脱氮除磷过程，因此，在理论上可以应用DO，ORP和pH作为实时控制参数控制污水处理过程，综述了当前国内外应用DO，ORP和pH作为实时控制参数控制污水处理过程的研究进展，并分析了目前我国在此研究方向存在的问题，指出进一步加强对污水处理实时控制技术应用基础研究的必要性和紧迫性，并使其与智能控制技术相结合，最终实现污水处理自动化，参27     

新型填料床-逐级曝气池一体化反应器水处理技术

为解决低浓度污水处理工艺脱氮除磷过程中存在的微生物碳源不足的问题,本文研制了新型填料床-逐级曝气串联反应器.填料床分别采用珊瑚砂、竹炭颗粒、钢渣为填料,在好氧、厌氧兼顾的环境下,实现化学除磷、生物除氮.试验采用模拟生活污水,COD、TN、TP、氨氮的浓度为170—190 mg.L-1、27—30 mg.L-1、8—10 mg.L-1,23—25 mg.L-1.反应器在第27天启动成功,100 d稳定运行结果显示,当HRT为14 h,曝气池DO为3.5 mg.L-1,反应器处理效果良好,出水中COD、TN、TP、氨氮的浓度分别为30.7 mg.L-1、5.59 mg.L-1、1.0 mg.L-1、4.67 mg.L-1,达到《城镇污水处理厂污染物排放标准》(GB18918—2002)中的一级B排放标准.经钢渣填料床处理后的污水,TP浓度降到1 mg.L-1左右,在不排泥的情况下,实现TP的高效去除,同时有效避免了除磷与脱氮过程对碳源的竞争,实现了生物法对水体中富余氮、磷的高效去除.     

软性填料序批式生物膜法的内源脱氮与外源脱氮

本文在软性填料序批式生物膜法同步脱氮除磷工艺探讨研究的基础上，再加一缺氧段，以进行反硝化，进一步提高脱氮效率，并对内源脱氮及不同添加比时的外源脱氮进行了比较，确定了该法脱氮除磷的最佳工艺及相应的工艺参数。     

三种生物除磷工艺的比较

比较了Ａ／Ｏ法、Ａ＾２／Ｏ法和ＳＢＲ法生物除磷工艺。结果表明，它们的除磷效果好；污染含磷量达６％以上、除磷系数达０．０４左右，是常规好氧生物处理的３倍。在系统除磷系数相同的条件下，Ａ＾２／Ｏ法取好，是常规好氧法的３倍；ＳＢＲ法次之，高速率Ａ／Ｏ法因不能经反硝化作用脱氮，去氮效果与常规好氧法相同。     

纤毛状生物膜脱氮除磷工艺调试研究

纤毛状生物膜脱氮除磷工艺(CNR)是一种高效的生物脱氮除磷工艺.好氧池中纤毛状生物膜填料的添加,固化了大量世代时间长的硝化菌,提高了硝化反应速度,而且成功地解决了好氧段硝化菌与聚磷菌的泥龄矛盾.通过对天津某污水处理厂进行CNR工艺中试,得出结论如下:填料比表面积大,微生物附着量高达1 350～1 500g·m~(-2);填料容易挂膜、脱膜,无堵塞现象,更不需要反冲洗,维护管理简单;填料上形成的生物膜中,微生物体系稳定,种群丰富,微生物相包括钟虫(vorticella)、轮虫(rotaria)、表壳虫(arcella)、吸管虫(tokophrya)等;采用CNR工艺对污水处理,常规项目的去除率均达到80%以上,出水水质除总氮达到一级B标准,其他均达到<城镇污水处理厂污染物排放标准>(GB 18918-2002)的一级A排放标准.     

基于ASM2D的广州市城市污水水质特征及碳源构成研究

城市污水处理厂提标改造的核心是生物高效脱氮除磷,而碳源是关键因素;充分利用碳源,既能提高脱氮除磷效率,又可节省投资。要提升污水处理工艺脱氮除磷效率的潜力,就有必要对城市污水的水质特征,特别是其中的碳源构成进行可靠的检测分析。文章分析了广州市2012—2016年18个季度的水质监测数据,并依据活性污泥数学模型ASM2D,采用膜过滤、曲线分析、差量计算等方法,获得了作为碳源的有机污染物COD的构成比例。结果表明,由于中心城区的功能趋同,广州市城市污水水质亦趋同,COD和BOD5没有显著性差异,进水COD质量浓度约为200 mg?L~(-1)左右,BOD5约为90 mg?L~(-1),可生化性稳定为0.47。在碳源构成中,溶解性COD稳定,均值为48.55 mg?L~(-1),其中可发酵的易生物降解有机物(SF)、发酵产物(SA)和惰性溶解性有机物(SI)分别为23.43、15.62和9.50 mg?L~(-1);颗粒性COD波动大,其中慢速可生物降解有机物(XS)占总COD的43.76%,根据可利用碳源计算的碳氮比和碳磷比分别达到5.57和61.19,相比传统水质指标提高20%以上,具有较大的生物高效脱氮除磷潜力,慢速可生物降解有机物是实现这一潜力的关键。研究结果可为广州市城市污水厂设计、改造、运营提供依据;结合计算机模拟技术,采用多点进水和多种回流,有助于充分利用碳源,提升活性污泥工艺的脱氮除磷效率。     

利用污水资源生产微藻生物柴油的关键技术及潜力分析

21世纪人类面临着能源与水资源的双重危机与挑战。微藻制备生物柴油和微藻深度脱氮除磷分别是开发新能源和污水深度处理方面的热点研究,但二者的单一系统均存在一定的局限性。基于微藻培养的污水深度处理与生物柴油生产耦合系统可以克服上述单一系统的局限性,在深度处理污水的同时,以污水为资源制备微藻生物柴油。藻种筛选是耦合系统的前提与重点,其筛选原则为在二级出水条件下生长快、氮磷去除效率高和单位藻细胞油脂含量高。合适的藻细胞分离收获及油脂提取技术能够降低能耗;而油渣厌氧发酵可充分回收其中的能量,同时减少油渣对环境造成的不利影响。根据耦合系统的工艺特点,每年全国利用该耦合工艺以生活污水为原料生产微藻生物柴油的潜力约397万t。     

膜生物反应器脱氮除磷工艺的研究进展

膜生物反应器是近年新发展起来的高效污水处理工艺，文章重点介绍了膜生物反应器的脱氮除磷工艺；单一反应器间歇曝气膜生物反应器工艺和A/O形式的膜生物反应器工艺。总结了国内外研究的工艺特点、技术参数和处理效果。分析了技术参数，运行方式对处理效果的影响，提出了今后研究方向和应用前景。     

N2O emission from a sequencing batch reactor for biological N and P removal from wastewater

Nitrous oxide （N2O） is a greenhouse gas that can be released during biological nitrogen removal from wastewater. N2O emission from a sequencing batch reactor （SBR） for biological nitrogen and phosphorus removal from wastewater was investigated, and the aims were to examine which process, nitrification or denitrification, would contribute more to N2Oemission and to study the effects of heterotrophic activities on N2O emission during nitrification. The results showed that N2O emission was mainly attributed to nitrification rather than to denitrification. N2O emission during denitrification mainly occurred with stored organic carbon as the electron donor. During nitrification, NaO emission was increased with increasing initial ammonium or nitrite concentrations. The ratio of N2O emission to the removed ammonium nitrogen （N2O- N/NH4-N） was 2.5% in the SBR system with high heterotrophic activities, while this ratio was in the range from 0.14% to 1.06% in batch nitrification experiments with limited heterotrophic activities.     

On-line controlling system for nitrogen and phosphorus removal of municipal wastewater in a sequencing batch reactor (SBR)

The objectives of this study were to establish an on-line controlling system for nitrogen and phosphorus removal synchronously of municipal wastewater in a sequencing batch reactor (SBR). The SBR for municipal wastewater treatment was operated in sequences: filling, anaerobic, oxic, anoxic, oxic, settling and discharge. The reactor was equipped with on-line monitoring sensors for dissolved oxygen (DO), oxidation-reduction potential (ORP) and pH. The variation of DO, ORP and pH is relevant to each phase of biological process for nitrogen and phosphorus removal in this SBR. The characteristic points of DO, ORP and pH can be used to judge and control the stages of process that include: phosphate release by the turning points of ORP and pH; nitrification by the ammonia valley of pH and ammonia elbows of DO and ORP; denitrification by the nitrate knee of ORP and nitrate apex of pH; phosphate uptake by the turning point of pH; and residual organic carbon oxidation by the carbon elbows of DO and ORP. The controlling system can operate automatically for nitrogen and phosphorus efficiently removal.     

Practical consideration for design and optimization of the step feed process

Based on the anoxic/oxic (A/O) step feed process, a modified University of Cape Town (UCT) step feed process was developed by adding an anaerobic zone and adjusting sludge return pipeline. Performance evaluation of these two types of processes was investigated by optimizing operational parameters, such as the anaerobic/anoxic/oxic volumes, internal recycle ratios, and sludge retention times, for removal of chemical oxygen demanding (COD), nitrogen, and phosphorus. Results showed high removal efficiencies of COD of (85.0±1.7)%, ammonium of (99.7±0.2)%, total nitrogen (TN) of (85.5±1.7)%, phosphorus of (95.1±3.3)%, as well as excellent sludge settleability with average sludge volume index of (83.7±9.5) L·mg^-1 in the modified UCT process. Moreover, (61.5±6.0)% of influent COD was efficiently involved in denitrification or phosphorus release process. As much as 35.3% of TN was eliminated through simultaneous nitrification and denitrification process in aerobic zones. In addition, the presence of denitrifying phosphorus accumulating organisms (DNPAOs), accounting for approximately 39.2% of PAOs, was also greatly beneficial to the nitrogen and phosphorus removal. Consequently, the modified UCT step feed process was more attractive for the wastewater treatment plant, because it had extremely competitive advantages such as higher nutrient removal efficiencies, lower energy and dosages consumption, excellent settling sludge and operational assurance.     

废水生物脱氮中N_2O和NO_x的产生和作用

废水生物脱氮中N2O和NOx来源于硝化、反硝化、厌氧氨氧化和化学反硝化等过程.电子受体和供体浓度、pH、缓冲剂类型、有机负荷、微生物种类及其相互作用等都会影响这些气态中间产物的产生.NO2能够氧化氨和强化好氧和厌氧氨氧化,NO能够阻止C2H2对好氧氨氧化活性的抑制,两者对好氧氨氧化活性的恢复至关重要.所有这些表明,废水生物脱氮的气态中间产物N2O和NOx在氮的生物转化中具有重要的正面作用,甚至必不可少.基于NO2曝气技术和Brocadiaanammoxidans与Nitrosomonas协同作用的废水生物脱氮新技术开发是今后一段时间的重要研究方向.图4参35     

Effect of short-term atrazine addition on the performance of an anaerobic/anoxic/oxic process

In this study, an anaerobic/anoxic/oxic (A²O) wastewater treatment process was implemented to treat domestic wastewater with short-term atrazine addition. The results provided an evaluation on the effects of an accidental pollution on the operation of a wastewater treatment plant (WWTP) in relation to Chemical Oxygen Demand (COD) and biological nutrient removal. Domestic wastewater with atrazine addition in 3 continuous days was treated when steady biological nutrient removal was achieved in the A²O process. The concentrations of atrazine were 15, 10, and 5 mg·L^?1 on days 1, 2 and 3, respectively. The results showed that atrazine addition did not affect the removal of COD. The specific NH₄ ⁺ oxidation rate and NO₃ ^? reduction rate decreased slightly due to the short-term atrazine addition. However, it did not affect the nitrogen removal due to the high nitrification and denitrification capacity of the system. Total nitrogen (TN) removal was steady, and more than 70% was removed during the period studied. The phosphorus removal rate was not affected by the short-term addition of atrazine under the applied experimental conditions. However, more poly-hydroxy-alkanoate (PHA) was generated and utilized during atrazine addition. The results of the oxygen uptake rate (OUR) showed that the respiration of nitrifiers decreased significantly, while the activity of carbon utilizers had no obvious change with the atrazine addition. Atrazine was not removed with the A²O process, even via absorption by the activated sludge in the process of the short-term addition of atrazine.     

城市污水生物除磷系统的特点工艺及其改进

本文以废水生物除磷的原理及特点为基础，介绍了城市污水生物除磷的主要工艺及其改进方法。     

新型废水生物脱氮的微生物学研究进展

生物脱氮是含氮废水处理公认的最佳处理方式,随着对生物脱氮微生物学原理研究的不断深入,许多新的生物脱氮特殊菌株或菌群及微生物转化机制不断被发现.本文在传统生物脱氮过程机理上,结合最近国内外生物脱氮的新发现,就短程硝化反硝化、同时硝化反硝化、厌氧氨氧化的微生物学原理进行了阐述.图1表2参23     

Influence of carbon source and temperature on the denitrifying phosphorus removal process

To supply the valuable operating parameters for the popular usage of the new denitrifying phosphors removal process, it is essential to study the dominant biochemical reactions and the characteristics of denitrifying phosphorus removing bacteria (DPB). Thus, parallel batch experiments using DPB sludge were carried out to assess the effect of substrates (sewage, HAc, and endogenous carbon source) on denitrifying dephosphorus removal efficiency in this study. The results showed that the initial specific phosphorus release rate increased with the high concentration of the short-chain volatile fatty acids ratio in the influent, and sufficient phosphorus was released by DPB. This improved the subsequent denitrification and phosphorus uptake efficiency. The specific endogenous denitrification mainly relies on the internal carbon source (PHB) stored by poly-P bacteria. Denitrifying phosphorus removing bacteria were very hungry when the internal PHB was consumed. Consequently, the specific endogenous denitrification rate was low and the phosphorus uptake did not happen. On the other hand, in the experiment, the denitrifying phosphorus removal performance under two temperature conditions (8–10°C and 25–26°C) was also investigated and analyzed. It was found that the lower temperature decreased the specific phosphorus release and uptake rate, but did not inhibit the denitrifying phosphorus removal completely. Therefore, the negative influence of the low temperature on the overall phosphorus removal was not significant.