人工湿地高效好氧反硝化菌的分离鉴定及反硝化特性研究

从增氧型复合垂直流人工湿地中采集样品,利用间歇曝气法富集好氧反硝化菌,并进行分离纯化,共得到10株好氧反硝化菌。其中编号为B13的菌株在初始硝态氮含量为277.23mg·L-1、碳氮比为5的条件下,24h的硝态氮去除率达92.80%,亚硝态氮积累只有12.57mg·L-1,脱氮速率达到20.58mg·L-·1h-1。16S rDNA序列分析表明,该菌与Pseudomonas stutzeri同源性达100%。选用四因素三水平L（934）正交试验表设计实验,通过测定对硝态氮去除能力和亚硝态氮的积累量,研究碳源、碳氮比（C/N）、pH以及溶解氧含量（DO）4种不同因素对B13号菌株好氧反硝化性能的影响。结果表明,该菌株对硝态氮的去除率最大可达99.88%,几乎没有亚硝态氮积累。对硝态氮去除率影响最大的因素为碳氮比,其次为pH,溶解氧含量和碳源。对应的最优条件是碳源为葡萄糖,碳氮比为10,pH为9,溶解氧含量为1.84～3.57mg·L-1。     

反硝化技术对模拟养殖池塘修复的研究

浙江奉化市池塘的底泥经过反复培养、驯化,从中筛选、分离出反硝化细菌,在模拟实验条件下,研究其对不同浓度的硝酸盐氮和亚硝酸盐氮的去除情况,讨论反硝化菌种的生长情况。结果表明,在初始浓度为1、25、50mg·L^-1的硝酸盐氮和亚硝酸盐氮模拟池塘中,随着实验的进行,对污染物的去除效果逐渐提高。其中在1mg·L^-1的浓度组中,3d内硝酸盐氮和亚硝酸盐氮去除率就分别达到了95．8％和90．2％;在25mg·L^-1的浓度组中,第6d硝酸盐氮和亚硝酸盐的去除率分别为93．8％和87．8％;在50mg·L^-1的浓度组中,第6d硝酸盐氮和亚硝酸盐的去除率分别为89．7％和78．7％。此外,反硝化菌对硝酸盐氮的去除效果略优于亚硝酸盐氮,而且硝酸盐氮和亚硝酸盐氮的浓度越低,对其去除效果越好,达到稳定状态的时间越短。在模拟池塘中,菌种的生长情况与硝酸盐氮和亚硝酸盐氮的浓度呈负相关,即污染物的浓度越高反硝化菌的生长情况越差。对反硝化菌的生态影响因子研究表明,其反硝化最适宜的pH值为6～7,温度为25～35℃;而且在同一pH值和温度条件下,硝酸盐氮和亚硝酸盐氮浓度越低,反硝化菌对其去除效果越好。     

茶园一株异养硝化-好氧脱氮菌的鉴定及特性研究

经过菌株富集培养、 分离纯化等一系列步骤,从山东茶园土壤中筛选出一株菌株F1,通过对其进行16S rRNA测序及生理生化指标的测定,结合负染电镜观察结果,参照《伯杰细菌鉴定手册》鉴定该菌株属于黄杆菌属。同时对其硝化和反硝化脱氮能力进行了研究。结果表明,菌株F1能在利用有机物的同时进行硝化和反硝化脱氮作用。经过60 h的培养,在硝化培养基上对氨氮的去除率达到84.54%,对亚硝酸盐的去除率达到91.87%; 在反硝化培养基上对硝酸盐的去除率达到79.17%,对亚硝酸盐的去除率达到84.30%; 在以铵态氮为初始氮源的条件下脱氮能力最强。     

生物反应器电子受体反硝化聚磷PAOs-GAOs竞争及N2O释放特性

利用厌氧-缺氧-好氧序批式生物反应器（Anaerobic/Anoxic/Oxic-Sequencing Batch Reactor, An/A/O-SBR）,以乙酸钠为电子供体,NO3-/NO2-为电子受体,控制反硝化电子受体电子需求为90 mmol/L,经长时间驯化,考察了不同电子受体驯化SBR反硝化除磷及N2O释放特性,并利用化学计量法确定了聚磷菌（Phosphorus Accumulating Organisms, PAOs）和聚糖菌（Glycogen Accumulating Organisms, GAOs）间竞争关系。结果表明,NO3-还原过程中,SBR系统总氮（Total Nitrogen, TN）和总磷（Total Phosphorus, TP）去除率均达95%以上,平均N2O产率为2.4%,PAOs转化碳源（CODin）和反硝化脱氮比例分别为62.0%和76.2%。NO2-增加,厌氧段糖原（Gly）酵解性能增强,Gly消耗与碳源转化比例（ΔGly/CODin）由0.67增至0.80,PAOs活性受抑制,聚磷（Poly-P）合成减少,GAOs竞争优势增强。NO2--N为30 mg/L,SBR内TP去除率降至50.5%,平均N2O产率达9.9%,PAOs转化碳源和脱氮比例分别降至36.0%和50.6%。PAOs-GAOs共生体系内,GAOs反硝化脱氮过程,削弱了高NO2-对PAOs反硝化除磷的抑制,缺氧阶段NO2-/HNO2积累耦合GAOs反硝化脱氮比例增加,导致高NO2-下TP去除率下降和N2O产率增加。     

脱氮副球菌的好氧反硝化特性及对养殖水体中氮素的控制

以一株脱氮副球菌（Paracoccus denitrificans）为试验菌株,研究了其在好氧环境下的最适生长条件以及在不同溶氧条件下对NO2--N、NO3--N的转化去除情况。结果表明,脱氮副球菌好氧下的最适生长温度为30℃,最适生长pH值为7.0。在溶解氧比较充足的情况下（6.6～7.3mg.L-1）,脱氮副球菌对NO2--N、NO3--N的去除以同化吸收为主,少部分是经由反硝化作用去除,最大去除率可达100%和97.58%。随着溶氧的降低,脱氮副球菌的反硝化能力增强,NO2--N、NO3--N通过反硝化作用去除的比例增加。将活菌数≥109个.mL-1的脱氮副球菌按1.0、2.5mg.L-1的浓度加入养殖水体,在10d内可使养殖水体中的NH4＋-N下降41.89%～49.23%,NO2--N下降33.33%～42.86%,NO3--N下降48.28%～67.74%,对养殖水体中的氮素污染具有较好的控制效果。研究显示,脱氮副球菌的好氧反硝化作用可以为养殖水体有氧条件下的脱氮提供一条新的思路。     

养殖废水中异养硝化细菌的分离筛选和鉴定

为了获得脱氮功能强的异养硝化菌株用于养殖废水的脱氮处理,通过富集、分离和纯化等步骤,并结合格利斯试剂检验菌株硝化能力的方法,从某养猪场污水处理池污泥中分离筛选了4株具异养硝化功能的菌株,分别标号为79、84、L116、L117,通过16SrDNA序列分析和美国全自动微生物分析仪Biolog鉴定,4株菌均为粪产碱杆菌（Alcaligenesfaecalis）,并验证了这4株菌的硝化能力。结果表明,当液体培养基初始氨氮浓度为90mg.L-1左右时,在振荡培养48h内,菌株79、84、L116、L117培养基中氨氮和总氮均快速下降,氨氮去除率分别达到44.4%、47.9%、61.3%和56.4%,总氮（除菌）去除率达到39.9%、38.5%、43.4%和40.7%。     

一株具有多途径氮代谢功能的荧光假单胞菌

为研究全自养脱氮过程，采用斯凯尔曼亚硝化单胞杆菌培养基，从南京某城市污水处理厂序批式处理系统（SBR）中分离得到一株具有多途径氮代谢功能的荧光假单胞菌Pseudomonas fluorescens dN13。该菌株在有氧条件下，无有机碳源存在，能进行氧化NH3-N产能代谢生长；有有机碳源存在且NO2^- -N和NO3^- -N的浓度较高时，它能将NO2^- -N和NO3^- -N还原为NH3-N。在厌氧条件下，只有乙酸钠作碳源时，该菌株仍能进行硝酸亚硝酸还原（反硝化）作用。在这个具有多途径氮代谢功能的菌株细胞内，硝化反硝化过程耦合成为可能。     

一株根际好氧反硝化菌的筛选及其反硝化条件研究

为丰富好氧反硝化菌株种类,本文从不同环境样品中富集筛选好氧反硝化细菌,最终得到一株高效根际菌株RWX31,其在初始NO3--N浓度140 mg/L时24 h去除率为82％,并在好氧条件下可进行反硝化作用产生N2O.通过单因素试验研究该菌株进行反硝化作用的条件和特性,结果表明,菌株RWX31最适培养基条件分别为:以柠檬酸钠为碳源,接种量为1％,Mg2+浓度为0.05 g/L,反硝化初始氮源中NO2--N比例为0.最适培养条件为:温度28℃～32℃,pH为7.0～7.5,C/N为8～ 12,DO浓度约6.5 ～ 7.0 mg/L.在这些培养条件下菌株NO3--N去除率可增至90％以上.菌株RWX31的NO3--N去除能力高于以往报道的反硝化菌株,是一株具有实际应用价值和潜力的菌株.     

厌氧/缺氧/好氧生物接触氧化处理低碳氮比污水的物料平衡

为了提高低碳氮比污水的治理效果,提出了厌氧/缺氧/好氧-生物接触氧化脱氮除磷工艺(anaerobic anoxic oxic-biological contact oxidation,A2/O-BCO),研究了该工艺处理生活污水的脱氮除磷性能,建立了该系统处理过程的碳(以化学需氧量计,chemical oxygen demand,COD)、氮、磷的物料衡算公式,同时分析评价了不同硝化液回流比(100%,200%,300%,400%)下各指标的物料平衡情况。结果表明,该工艺在充分利用原水碳源、深度脱氮除磷方面具有较强的优势,系统COD主要在A2/O中厌氧段被利用,通过反硝化聚磷菌反硝化除磷脱氮;系统COD的物料衡算公式平衡百分比分别为96.4%、99.6%、98.7%和98.3%,氮的物料衡算公式平衡百分比分别为99.7%、98.2%、99.2%和96.5%,磷的物料衡算公式平衡百分比分别为92.0%、98.1%、93.3%和90.4%;荧光原位杂交表明生物膜中有厌氧氨氧化菌存在,且其数量占全菌比例的0.6%~2.7%,生物接触氧化的氮损失可能是由于发生了厌氧氨氧化反应;在硝化液回流比为300%时,系统氮、磷去除效果最好,出水达到国家城镇污水处理厂污染物排放标准一级A标准。该研究有助于更好地理解和分析工艺系统有机物、氮和磷的分布及变化情况,并且为评价试验数据的可靠性以及数学模型的建立提供了理论依据和指导,能更好地推广到分散型、量小且日变化系数较大的农村生活污水的治理事业中。     

地下水硝酸盐去除中反硝化微生物的研究进展

地下水硝酸盐污染已经成为一个全球问题,由于饮用高硝酸盐含量的地下水会增加高铁血红蛋白症和癌症风险,地下水硝酸盐污染受到越来越多的关注。反硝化脱氮是地下水硝酸盐脱氮的主要途径之一。本文就参与地下水硝酸盐去除的反硝化微生物种类、反硝化机理、碳源类型以及地下水污染中微生物作用的国内外研究现状进行了较全面系统的评述。在此基础上,提出了该类研究中存在的不足,包括实验室研究较多但野外研究较少,野外原位应用中对特定微生物特性方面研究缺乏,碳源利用率低和硝酸盐去除速度慢,去除过程中有效微生物的代谢途径仍不清楚等问题。针对这些问题,本文认为以后的研究应该进一步开发野外原位应用中反硝化微生物资源,并借助先进的分子方法和功能基因鉴定此类特殊微生物的种类、功能及其生态学行为,选择最佳碳源,完整深入地了解地下水硝酸盐去除中微生物的代谢过程,识别反硝化过程中氮的来源与去向,为寻找提高处理效率的方法提供理论依据,真正将理论和实践结合起来。     

Mercury pathways in municipal wastewater treatment plants

A nine-week sampling and analysis program was completed at a large municipal wastewater treatment plant to characterize the fate of Hg entering the plant. Mercury removal in primary treatment averaged 79%, and the average Hg removal across the entire plant was approximately 96%. Mercury loadings on the secondary (activated sludge) treatment process were elevated to near plant influent levels due to the recycle of spent scrubber water from sewage sludge incinerator emissions control equipment. This internal recycle of spent incinerator scrubber water resulted in elevated Hg loadings to the incinerators, and effectively reduced the Hg control efficiency of the emissions control equipment to near zero. Measurements indicate that approximately 95% of the Hg mass entering the plant is discharged to the atmosphere via sludge incinerator emissions. These results indicate that municipal wastewater treatment facilities can remove Hg from wastewater quite effectively; however, where wastewater sludge is incinerated, almost the entire mass of Hg removed from the wastewater can be discharged to the atmosphere.     

15N同位素稀释法测定燕麦根际固氮菌固氮量的研究

用15N同位素稀释法对接种到燕麦上的不同固氮菌的固氮能力进行了测定,结果表明:固氮菌处理的地上植株15N原子百分超为1.0871%～1.3791%,其中Pseudomonas spN4最低(1.0871%);植株地下部分为1.0921%～1.2751%,Pseudomonas spN4也是最低(1.0921%)。Pseudomonas spN4、A.lipoferumO6和Zoogloea spW6固氮能力较好。植株全氮含量增加2.08%～39.58%,A.lipoferumO6处理的全氮含量最高(39.58%)。接种固氮菌能够提高燕麦的全氮含量、固氮百分率和固氮量。     

Short-Term Effects of Wastewater Land Application on Soil Chemical Properties

Land application of wastewater has been accepted as an effective wastewater treatment method and disposal option in semiarid and arid areas in the world. Although it has economical, environmental, and social benefits, it is sometimes questioned as an environmentally sound method. Water mass balance method has proved to be an effective approach to designing a wastewater land application system to remove nitrogen at the municipal wastewater treatment plant at the City of Littlefield, Texas, USA. The study in this paper was to evaluate the short-term effects of wastewater land application on soil chemical properties at the same site from 16 June 2006 to 28 June 2007 with the system designed by the water mass balance method. Soil samples were taken at the start and at the end of this study at different depths from soil surface down to 91 cm at the research site (54?×?18 m), and analyzed for pH, total Kjeldahl nitrogen, nitrate–nitrogen, ammonia–nitrogen, electrical conductivity, calcium, magnesium, sodium, and sodium adsorption ratio. The results showed that there was no negative change of those soil chemical properties during the research period in this wastewater land application system designed by water mass balance method.     

污泥反硝化除磷-诱导磷结晶工艺中硝化池内的微生物特性

为了探究双污泥系统下反硝化除磷-诱导磷结晶工艺中硝化池内微生物特性,该文利用原位荧光杂交（fluorescence in situ hybridization,FISH）技术、电子显微镜扫描（scanning electron micrograph,SEM）方法和Image-Pro Plus（IPP）软件考察了该工艺中硝化细菌的种群结构、形态和硝化污泥微观三维结构图。结果表明：该工艺中硝化池内氨氧化细菌（ammonia-oxidizing bacteria,AOB）数量要多于亚硝酸盐氧化细菌（nitrite-oxidizing bacteria,NOB）,占总细菌的比例分别为46.2%,28.5%,且AOB处于污泥颗粒外层而NOB处于污泥颗粒内层,可能由于NOB利用AOB的代谢产物所致;工艺中硝化细菌多以球形或短杆菌为主,NOB生长时多以几个细胞形成小团聚体,而AOB生长时则形成大的团聚体;通过硝化污泥微观三维结构发现,污泥外层呈密实状而内层较疏松且有空洞存在,可能由于污泥外层和内层微生物的丰度差异、营养物质和溶解氧的浓度差异所致。此外,与传统的单污泥污水处理工艺相比,双污泥工艺明显地增强了硝化细菌的生长和富集能力。     

Land Disposal of Centrate from Biosolids Production

Arid land and riparian plants were irrigated with a liquid wastewater stream (centrate) from biosolids production at a municipal sewage treatment facility. Centrate containing approximately 1000 mg/l ammonia nitrogen was diluted with Tucson city tap water to provide treatments of 2.5, 5, 10, 25, 50, and 100% centrate, along with a dilution water control. Plants grown in 19-l containers in a greenhouse were irrigated daily with 6.7 l of solution over a 7-week period. All species exhibited a fertilizing effect at concentrations up to 5 and 10% centrate, equivalent to approximately 50 and 100 mg/l NH₃–N, but then inhibitory above 100 mg/l. No plants survived on the 50 or 100% treatments. If centrate were to be diverted from the wastewater facility to be disposed of on the land, it was estimated that the total nitrogen content of the biosolids produced by the plant would be reduced by 11%. This reduction would have only a small impact on the value of the biosolids for soil amendment applications.     

Anammox反应器的启动及其菌群演变的研究

为了研究工艺条件对反应器内微生物多样性的影响,该论文采用城市污水处理厂活性污泥接种,通过培育硝化污泥,进行了启动厌氧氨氧化(Anammox)反应器的试验,并对启动过程中细菌的多样性变化作了跟踪研究。研究结果表明,以好氧活性污泥作为接种物,可成功地培育硝化生物膜;通过反应器运行条件的控制,硝化生物膜可从进行好氧氨氧化反应过渡到进行厌氧氨氧化反应。在此过程中,异养型细菌的数量大幅度下降,硝化细菌、反硝化细菌和厌氧氨氧化细菌的数量增大,推测它们都与厌氧氨氧化作用有关。运用PCR-DGGE技术证明,随着反应器运行时间的延长,菌群发生明显变化并呈现简化趋势。     

氨化细菌对植物浮岛人工湿地中有机氮强化分解

鉴于人工植物浮岛生态塘出水氨氮浓度高、去除率较低这一难题,将实验室筛选的一株具有高效氨化能力的工程菌应用于植物浮岛人工湿地中进行强化分解有机氮试验,以提高植物浮岛生态系统中有机氮、氨氮的去除效果。菌株动力学试验研究表明：有机氮分解反应符合零级反应,降解速率为0.76 mg/(L·h),在48 h时有机氮的分解率为81.80%。采用常绿植物蕙兰构建植物浮岛污水处理模拟生态系统,以未加菌剂做为对照组,以加入氨化细菌菌剂做为试验组,进行对比试验。结果表明,在48 h时未加菌剂的植物浮岛中有机氮的分解率为75.66%,有机氮质量浓度为8.23 mg/L;加入菌剂的植物浮岛中有机氮的分解率为86.50%,有机氮质量浓度为4.40 mg/L,加入菌剂比未加菌剂时有机氮的分解率提高了11.16%,有机氮质量浓度降低3.83 mg/L。在72 h时,加入菌剂的植物浮岛中氨氮质量浓度为6.74 mg/L;而未加菌剂在72 h时氨氮还未开始降解,在144h时氨氮质量浓度为9.86 mg/L-1。加入氨化细菌菌剂后,植物根系能够更多的吸收氨氮,为植物根系周围的微生物群提供了充足的氧气进行硝化作用,提高了植物浮岛对氮素的去除效果。该研究可为人工湿地中提高氮素去除效果提供参考。     

Performance of Phragmites Australis and Cyperus Papyrus in the treatment of municipal wastewater by vertical flow subsurface constructed wetlands

The use of constructed wetlands to treat municipal wastewater reduces energy consumption and therefore economic costs, as well as reduces environmental pollution. The purpose of this study was to compare the purification capacity of domestic wastewater using two species of plants sown in subsurface constructed wetlands with vertical flow built on a small scale that received municipal wastewater with primary treatment. The species used were Phragmites Australis and Cyperus Papyrus. For this purpose, a constant flow of 0.6 m³ day⁻¹ was fed from the primary lagoon to each of the two wetlands built on a pilot scale with continuous flow. Each unit was filled with granite gravel in the lower part and with silicic sand in the upper part of different granulometry, the porosity of the medium was 0.34, with a retention time of 1.12 days and a hydraulic load rate of 0.2 m day⁻¹. To analyze the purification capacity of wastewater, physical, chemical and biological parameters were monitored during three months. Samples were taken at the entrance and exit in each experimental unit. The results obtained in the experimental tests for the two species of plants, indicated that the Cyperus Papyrus presented a greater capacity of pollutants removal as biochemical oxygen demand (80.69%), chemical oxygen demand (69.87%), ammoniacal nitrogen (69.69%), total phosphorus (50%), total coliforms (98.08%) and fecal coliforms (95.61%). In the case of Phragmites Australis retains more solids. The species with greater efficiency in the treatment of municipal wastewater for this study was Cyperus Papyrus.     

人工湿地-电活性菌藻膜技术处理养猪废水中试试验

人工湿地由于具有运行成本低、维护简单等优点而被广泛应用于养殖废水处理。然而,人工湿地技术普遍存在污染物去除效率受温度影响大等问题。在该研究中,通过构建电活性菌藻生物膜来强化人工湿地系统,对养猪废水进行了自然温度下的处理效能与微生物群落研究,在室外开展了18个月试验,结果表明：电活性菌藻生物膜强化组在夏季化学需氧量、氨氮、硝态氮、总氮、总磷、亚硝态氮的去除率分别达到98.26%、97.96%、85.45%、95.07%、94.64%和85.45%。在冬季化学需氧量、氨氮、硝态氮、总氮、总磷、亚硝态氮的去除率分别达到96.10%、91.56%、75.29%、89.94%、92.12%和83.15%。具有良好低温适应性。强化组冬季化学需氧量、氨氮、硝态氮、总氮、总磷、亚硝态氮的出水浓度均满足《禽畜养殖业污染物排放标准》（GB18596—2001）。相比未构建电活性菌藻生物膜的对照组,以上污染物去除率均分别提高。电活性菌藻膜在冬夏季节的优势微生物均为Cyanobium、Shewanella、Azoarcus,群落结构稳定性高,有利于促进冬季污染物去除率,为提高系统污水处理可靠性提供了保障。