垃圾渗滤液中有机污染物对厌氧氨氧化的影响研究

采用好氧活性污泥和厌氧颗粒污泥混合接种启动UBF厌氧氨氧化反应器,共耗时165d。反应器启动成功后,容积负荷达到了0.17kg总氮/(m3·d),NO2--N与NH4+-N去除率分别为100%和93%。在此基础上进行垃圾渗滤液有机物浓度梯度实验,研究其在不同有机物浓度下对厌氧氨氧化反应的影响作用。实验结果表明:NH4+-N和NO2--N的去除率随有机物浓度的增加依次降低。当TOC浓度小于100mg/L时,厌氧氨氧化运行稳定,NH4+-N和NO2--N的去除率分别达80%和95%以上;当TOC浓度大于200mg/L时,厌氧氨氧化反应减弱,体系中出现了明显的异氧反硝化反应;当TOC浓度大于500mg/L时,厌氧氨氧化反应几乎完全停止。由于该垃圾渗滤液有机污染物多为难降解的大分子,具有毒性、易降解,有机物的含量较少,因此认为其对厌氧氨氧化的毒性抑制远比竞争性抑制大。     

垃圾渗滤液对厌氧氨氧化混培菌活性的影响研究

采用厌氧复合床,经自养型反硝化过程转化,成功启动了厌氧氨氧化反应器,共耗时165d。反应器启动成功后,容积负荷达到了0.17kg总氮/(m3.d),NO2--N与NH+4-N去除率分别为100%和93%。在此基础上,研究了垃圾渗滤液的亚硝化出水对厌氧氨氧化混培菌活性的影响。研究结果表明:在低质量浓度基质(NH+4-N～60mg/L,NO2--N～60mg/L)条件下,垃圾渗滤液亚硝化出水对厌氧氨氧化反应产生了微弱的影响,氨氮的平均抑制率为10.73%,亚氮的平均抑制率为11.71%。     

有机碳对氨氧化细菌及氨氧化古菌的影响

氮是水生态系统初级生产力的限制性生源要素,也是造成黑臭水体的重要污染物。微生物是氮循环的驱动泵,硝化作用及反硝化是微生物的特有过程,也是氮素生物地球化学循环以及氮素去除过程中最为关键的步骤。通过分析体系中氮转化、氨氧化古菌(AOA)及氨氧化细菌(AOB)数量和活性对不同有机炭的响应发现,有机碳的添加增大了氨氧化古菌在氨氧化菌群中的比例,而氨氧化细菌比氨氧化古菌对铵根离子的降低更为敏感体系的潜在硝化速率与氨氧化细菌的氨单加氧酶基因拷贝数具有正向相关性。本研究结果对如何通过促进水体自身氮转化活性而快速削减水体中氨氮提供了指导。     

厌氧氨氧化脱氮技术的研究进展

介绍厌氧氨氧化技术机理以及与此相关的微生物生理生态学特征,综述该脱氧技术研究现状及具体应用以及不同反应器应用厌氧氨氧化技术的脱氧情况,比较不同脱氧工艺,探讨了厌氧氨氧化技术未来的研究重点。     

厌氧氨氧化处理稀土废水试验研究

采用UASB反应器,在最短时间内,预处理稀土冶炼过程中排放的较高浓度的NH4+-N废水。通过试验得出,反应器内的最佳控制温度为20～30℃,pH值为7.0～8.0,C/N比为3.5～4.5,此时微生物活性最好,表明用低C/N比预处理高浓度的NH4+-N废水是可行的。提高UASB反应器负荷,污泥可以很快适应高浓度废水,说明其具有处理高浓度废水且高负荷运行的可行性。     

厌氧氨氧化工艺及其污泥颗粒化的试验研究

厌氧氨氧化工艺是目前最经济简捷的一种新型生物脱氮工艺.本文以两种普通污泥分别接种两个UASB反应器,实现了厌氧氨氧化工艺的启动和稳定运行,培养获得了厌氧氨氧化颗粒污泥,并研究了各种因素对工艺运行的影响规律,结果表明:(1)以厌氧颗粒污泥与好氧活性污泥的混合物以及河底沉积物分别接种启动运行两个小试UASB反应器,以含氨氮和亚硝酸盐氮的无机配水为进水,分别经过115 d和210 d的运行,两个反应器均成功实现了厌氧氨氧化过程,氨氮去除率分别达50%和70%,氨氮去除负荷达0.35和0.29 kgNH3-N/(m3·d),相应的亚硝酸盐氮去除率分别为55%和67%;(2)在两个反应器随后146 d和306 d的稳定运行期间,工艺性能逐步上升,氨氮去除率分别达86%和95%,氨氮去除负荷达0.71和1.20 kgNH3-N/(m3·d),相应的亚硝酸盐氮去除率分别为83%和92%,所产气体中氮气含量高于96%;厌氧氨氧化工艺对进水负荷的突然变化有一定抵抗能力,但温度和溶解氧对工艺性能影响较大;(3)在两个反应器中均获得了厌氧氨氧化颗粒污泥,粒径约为0.6～1 mm,VSS/SS为0.6～0.8,颜色多呈棕黄色,也有少量小粒径颗粒呈红色,在扫描电镜下观察,发现颗粒中的优势菌为不规则球菌,与文献报道的厌氧氨氧化细菌类似;(4)在对颗粒污泥内部微观结构观察和研究的基础上,提出了三种厌氧氨氧化颗粒污泥的形成机理:蜕变附着生物膜机理、无机晶核附着生物膜机理和自凝聚机理;(5)对厌氧氨氧化工艺的主要影响因素进行了系统的研究,发现其最适温度在30～35℃之间,最适pH约为8.2,溶解氧对工艺的抑制作用很强,其浓度应控制在0.01 mg/L以下,由河底污泥培养获得的厌氧氨氧化污泥在上述最适条件下,最高氨氧化速率可达0.184 mgNH3-N/(mgVSS·d);(6)进水中一定浓度的有机物会对厌氧氨氧化工艺产生较大影响,有机物的引入会导致反硝化反应,产生基质竞争性抑制,进水中有机物的长期存在会导致污泥中异养细菌的生长,对厌氧氨氧化工艺产生不利影响.     

亚硝化-厌氧氨氧化工艺的试验研究

本文采用两种不同来源的活性污泥 ,利用ＣＳＴＲ反应器对亚硝化工艺处理高浓度氨氮自配废水进行了试验研究。试验结果表明 :(1)以处理饮料废水的活性污泥接种的ＣＳＴＲ反应器 ,从第 2 6天开始成功地实现了亚硝化 ,并从第 73天开始 ,反应器出水中检测不到ＮＯ3 -;反应器在进水氨氮容积负荷达到 1 4ｋｇ/(ｍ3 ·ｄ)时 ,氨氮去除率仍保持在 95 %以上 ;(2 )以处理生活污水的活性污泥为接种污泥的ＣＳＴＲ反应器 ,以高浓度氨氮废水在较高负荷下直接启动 ,从第 1天开始就成功地实现了亚硝化 ,至第 2 3天之后出水中检测不到ＮＯ3 -;亚硝化反应器的…     

好氧硝化污泥启动厌氧氨氧化试验研究

以好氧硝化污泥为培养污泥,采用经稀释的猪场废水启动厌氧氨氧化反应器,经过125 d的培养,根据ASBR反应器出水水样监测结果显示:ASBR反应器稳定运行后NH4+-N、NO2--N的去除率分别达到91.7%、92.0%,说明采用ASBR反应器,接种好氧硝化污泥可成功启动厌氧氨氧化反应器,验证了利用厌氧氨氧化工艺处理类似养殖废水的高氨氮废水的可能性.     

影响反硝化除磷与厌氧氨氧化耦合的因素

氧对厌氧氨氧化菌有毒,但在颗粒污泥和生物膜中的厌氧氨氧化菌对氧有较高的耐受能力,并且聚磷菌能消耗影响氧氨氧化菌生长的氧。厌氧氨氧化菌的生长无需有机物的参与,聚磷菌释磷需要吸收有机物,少量有机物的加入对厌氧氨氧化菌的活性影响不大。亚硝酸盐是厌氧氨氧化菌氧化氨的电子受体,较高浓度的亚硝酸盐对反硝化聚磷有抑制作用,但合适浓度的亚硝酸盐(该浓度可以通过驯化来提高)可以作为反硝化聚磷菌吸磷的电子受体。厌氧氨氧化过程中有硝酸盐生成,反硝化聚磷菌能利用这部分硝酸盐。另外,两类菌都适宜于中温略偏碱性的环境。因此,通过创造同时对厌氧氨氧化菌和反硝化聚磷菌有利的微生态环境,发挥两者在脱氮除磷方面的协同耦合作用,达到高度脱氮除磷,是极有前景的废水厌氧(缺氧)处理研究方向。     

低浓度氨氮条件下厌氧氨氧化反应器的启动研究

对低浓度氨氮(12mg/L)条件下厌氧氨氧化反应器的启动进行了试验研究,采用SBR在5个多月的时间内成功实现了厌氧氨氧化反应器的启动,并培养出了颗粒污泥。在稳定运行期间,氨氮和亚硝酸盐氮的去除率分别为94.5%和97.4%;氨氮、亚硝酸盐氮的容积负荷分别为11.4g/(m3·d)和11.1g/(m3·d)。     

Treatment of nitrogen-rich wastewater using partial nitrification and anammox in the CANON process.

Partial nitrification combined with Anammox in a single reactor (the CANON process) is an energy-efficient N-removal technology that could substantially lower the N-load of a WWTP by separate treatment of nitrogen-rich side streams, preventing the need for extensive expansion and reducing the total energy requirement. This study looks at the enrichment of Anammox from activated sludge and its application in the CANON process on lab-scale. The aim was to identify the critical process control parameters necessary for successful operation of CANON. An Anammox culture capable of removing 0.6 kg N/m3/d was enriched in 14 weeks in a sequencing batch reactor. Nitrifying biomass was inoculated into the Anammox reactor (10% v/v) together with limited oxygen supply (< 8 mL/min) to initiate the CANON process in continuous culture. The small flocs formed by the biomass (< 1000 microm) were sensitive to low O2 concentrations (< 0.1 mg/L) which prevented simultaneous nitrification and Anammox. Operation with 20 min aerobiosis and 30 min anaerobiosis was necessary to achieve sustained, completely autotrophic N-removal for an extended period at a rate of 0.08 kg N/m3/d. Essential process control parameters for stable CANON operation were the nitrite concentration, oxygen concentration, pH and the temperature.     

Coupling the SHARON process with anammox: model-based scenario analysis with focus on operating costs.

The combined SHARON-Anammox process for treating wastewater streams with high ammonia concentration is discussed. Partial nitritation in the SHARON reactor should be performed to such an extent that an Anammox-optimal nitrite:ammonium ratio is generated. The SHARON process is typically applied to sludge digestion rejection water in order to relieve the ammonium load recycled to the main plant. A simulation study for realistic influent conditions on a SHARON reactor with a fixed volume and operated with constant air flow rate reveals that the actual nitrite:ammonium ratio might deviate significantly from the ideal ratio and might endanger operation of the subsequent Anammox reactor. It is further examined how the nitrite:ammonium ratio might be optimized. A cascade pH control strategy and a cascade O2 control strategy are tested. Simulation results are presented and the performance of the different strategies is assessed and quantified in an economic way by means of an operating cost index. Best results are obtained by means of cascade feedback control of the SHARON effluent nitrite:ammonium ratio through setting an O2-set-point that is tracked by adjusting the air flow rate.     

二次凝聚法去除受污染原水TOC的影响因素研究

基于已有的研究成果通过混凝烧杯试验就二次凝聚法的凝聚剂投加量比例、快速混合强度和pH范围等因素对原水TOC去除效果的影响进行了研究。试验结果表明,将常规凝聚的加药量等分2次投加能取得最好的原水TOC去除效果,高混合强度有利于去除原水TOC,二次凝聚的最佳pH范围与原水pH范围一致。     

Granular biomass capable of partial nitritation and anammox

A novel and efficient way of removing nitrogen from wastewater poor in biodegradable organic carbon, is the combination of partial nitritation and anoxic ammonium oxidation (anammox), as in the one-stage oxygen-limited autotrophic nitrification/denitrification (OLAND) process. Since anoxic ammonium-oxidizing bacteria grow very slowly, maximum biomass retention in the reactor is required. In this study, a lab-scale sequencing batch reactor (SBR) was used to develop granular, rapidly settling biomass. With SBR cycles of one hour and a minimum biomass settling velocity of 0.7 m/h, OLAND granules were formed in 1.5 months and the nitrogen removal rate increased from 50 to 450 mg N L(-1) d(-1) in 2 months. The granules had a mean diameter of 1.8 mm and their aerobic and anoxic ammonium-oxidizing activities were well equilibrated to perform the OLAND reaction. Fluorescent in-situ hybridization (FISH) demonstrated the presence of both beta-proteobacterial aerobic ammonium oxidizers and planctomycetes (among which anoxic ammonium oxidizers) in the granules. The presented results show the applicability of rapidly settling granular biomass for one-stage partial nitritation and anammox.     

Influence of temperature and salinity on microbial structure of marine anammox bacteria

Anaerobic ammonium oxidation (anammox) is a type of biological oxidation mediated by a group of Planctomycete-like bacteria. Members of the genus Candidatus Scalindua are mainly found in marine environments, but not exclusively. This group is cultured using different inoculums and conditions; however, its optimal growth conditions are not clear. Additionally, little information is known about the factors that influence the activity and the selection of a population of marine anammox bacteria. This study was conducted to investigate the influence of temperature and salinity on the marine anammox community. To accomplish this, an up-flow fixed-bed column reactor was operated, and quantitative fluorescence in situ hybridization (FISH) with probes specific to dominant marine anammox bacteria was conducted. Anammox activity was observed at 20 and 30 °C, but not at 10 °C. A nitrogen removal rate of 0.32 kg TN m(-3) day(-1) was obtained at 20 °C. These results suggest that temperature affects the activity (nitrogen removal rate) of anammox bacteria, while salinity does not affect the activity in the marine anammox biofilm.     

Inhibition effect of swine wastewater heavy metals and antibiotics on anammox activity

The feasibility of anaerobic ammonium oxidation (anammox) process to treat wastewaters containing antibiotics and heavy metals (such as the liquid fraction of the anaerobically digested swine manure) was studied in this work. The specific anammox activity (SAA) was evaluated by means of manometric batch tests. The effects of oxytetracycline, sulfathiazole, copper and zinc were studied. The experimental data of the short-term assays were fitted with an inhibition model to identify the half maximal inhibitory concentration (IC(50)). After 24 h exposures, IC(50)-values equal to 1.9, 3.9, 650 and 1,100 mg L(-1) were identified for copper, zinc, sulfathiazole and tetracycline respectively. The effect of prolonged exposure (14 days) to oxytetracycline and sulfathiazole was studied by means of repeated batch-assays. Anabolism and catabolism reactions were active during the inhibition tests indicating that anammox bacteria could grow even in the extreme conditions tested. Considering the average concentrations expected in swine wastewaters, the inhibitors studied do not seem to represent a problem for the application of the anammox process. However, in order to verify the effect of these compounds on the growth of anammox bacteria, continuous culture experiments could be conducted.     

烟酸对毛纺废水活性污泥处理系统的影响

烟酸是合成辅酶的原料,也是许多微生物生长所必需的维生素之一。以静态试验得出的烟酸最佳投加浓度为依据,采用连续流的实际毛纺废水活性污泥试验及对照系统,进行连续投加烟酸的试验,维持曝气系统内烟酸浓度1mg/L。在16d的投加期间,投加组的平均CODCr去除率为对照组的1.3倍,活性污泥平均总脱氢酶活性和平均内源呼吸脱氢酶活性分别为对照组的1.34倍和1.44倍。     

Laboratory study on factors influencing nitrogen removal in marble chip biofilters incorporating nitritation and anammox

It remains challenging to integrate nitritation and anammox in ecologically engineered treatment systems such as passive biofilters that are packed with natural materials and have low energy inputs. This study explored the factors influencing nitritation-anammox through parallel operation of two laboratory-scale biofilters packed with large and small marble chips respectively. Clean marble chips (mainly CaCO3) had an alkalinity dissolution rate of 130 mg CaCO3/kg marble d when water pH approached 6.5. Marble chips effectively increased water pH and provided sufficient alkalinity to support nitritation-anammox in the biofilters. Ammonium and total nitrogen removal decreased by 47 and 26%, respectively, when nutrients were not amended to influent. An influent nitrite concentration above 8.9 mg N/L could inhibit anammox in thin biofilms of biofilters. Nitritation-anammox was enhanced with a hydraulic retention time of 2 d relative to 7 d, likely due to enhanced air entrainment. Size of marble chips rarely made a significant difference in nitrogen removal, possibly due to sufficient surface area available for bacterial attachment and alkalinity dissolution.     

浅议IC卡水表性能及应用

IC卡水表是一种具有预付费功能的水量计量仪表。从水表采用的阀门、电池和水表抗攻击性能三个方面对IC卡水表进行探讨。建议IC卡水表使用先导式阀门,采用方便更换电池、卡口封闭性好的IC卡水表。     

建筑物密度及排列方式对小区地表径流的影响

由于建筑物密度及排列方式是影响城市小区地表径流过程的重要因素,利用二维浅水方程建立了城市小区降雨径流模型并用BH法模拟建筑物,在利用相关人工降雨试验结果对模型参数进行率定的基础上,研究了不同建筑物密度、整齐与交错两种排列方式对城市小区地表降雨径流过程的影响。结果表明,随着建筑物密度的增大,达到平衡流量的汇流时间延长,二者满足指数函数关系;同一建筑物密度,交错排列方式下的汇流时间较整齐排列方式下的增幅更大,且两种排列方式的汇流时间差值随着建筑物密度的增大而增大。在有建筑物的断面上,平均水深与平均流速均大于无建筑物情况,且随着建筑物密度的增大而增大;在无建筑物的断面上,平均水深与无建筑物情况相近,而平均流速小于无建筑物情况,且随着建筑物密度的增大而减小;阻力系数随着建筑物密度的增大而增大,当建筑物密度小于16%时,阻力系数增幅较缓,当建筑物密度大于16%后,阻力系数显著增大。