低溶解氧丝状菌污泥微膨胀在SBR中的可行性

为了考察污泥微膨胀低能耗方法在间歇序批式(SBR)反应器中应用的可行性,采用实际生活污水进行试验,研究了污泥膨胀的启动、过度膨胀的抑制以及微膨胀的维持方法。结果表明,在pH7.0～8.0,温度(23±0.5)℃时,连续进水和单纯设置好氧段可以快速启动低氧丝状菌污泥膨胀。减少好氧时间和设置前置缺(厌)氧段可以有效地抑制丝状菌繁殖。微膨胀启动成功后,根据反应条件及处理要求的改变及时调整SBR运行方式,可将系统稳定地维持在微膨胀状态。低氧微膨胀状态下处理实际生活污水,出水氨氮浓度、磷浓度和悬浮物浓度(SS)可分别控制在4.5mg.L-1、0.2mg.L-1和5.0mg.L-1以下。每周期中联合利用DO、pH等在线参数可以实时了解系统生化反应的进程。     

溶解氧和碳源在人工湿地脱氮中的耦合关系分析

硝化-反硝化过程是人工湿地脱氮的主要途径。如何同时保障硝化-反硝化这一重要脱氮机制的畅通是提高湿地脱氮效率的关键。对溶解氧和碳源在人工湿地脱氮中的作用及其主要来源进行了描述,重点论述并分析了溶解氧和碳源在人工湿地脱氮中的耦合关系,合理调整进水中的碳氮比被认为是提高湿地脱氮效率的关键。     

低碳源条件下反硝化同步除磷脱氮的研究

对低碳源条件下反硝化同步除磷脱氮的影响因素进行了研究.结果表明,在低碳源情况下,硝基氮的消耗与磷的吸收呈线性关系,在厌氧段维持合适硝基氮与磷的质量比,可较好地实现同步去除氮磷,而污泥泥龄控制不当则影响反硝化除磷的效果.     

含盐污水SBR法生物脱氮模糊控制参数

为考察含盐污水SBR法生物脱氮实现模糊控制的可行性和有效性,以实际含盐生活污水作为研究对象,考察了脱氮过程DO、pH变化规律以及盐度冲击下pH的变化规律。结果表明含盐污水SBR法脱氮过程DO曲线变化不规律,应采用pH值为模糊控制参数。不同盐度下pH曲线有相似规律,曲线上出现的反映生物脱氮进程特征点：跃升点a（break point）、氨氮谷点b (ammonia valley)、硝酸盐峰c（nitrate apex）与有机物降解结束、硝化完成和反硝化完成有很好的对应关系;盐度升高后a、b推后出现;10 g•L^-1系统受盐度冲击时pH曲线依然遵从变化规律,但随着冲击盐度的升高特征点出现位置有所变化。冲击盐度高于30 g•L^-1,pH曲线逐渐趋于平缓,特征点a、b不明显但延长曝气时间时能够出现, c点受影响较小。     

Start‐up and enrichment of a granular anammox SBR to treat high nitrogen load wastewaters

BACKGROUND: Landfill leachate is characterized by low biodegradable organic matter that presents difficulties for the complete biological nitrogen removal usually performed by conventional biological nitrification/denitrification processes. To achieve this, the anaerobic ammonium oxidation (anammox) process is a promising biological treatment. This paper presents an anammox start‐up and enrichment methodology for treating high nitrogen load wastewaters using sequencing batch reactor (SBR) technology. RESULTS: The methodology is based on the gradual increase of the nitrite‐to‐ammonium molar ratio in the influent (from 0.76 to 1.32 mole NO₂^?‐N mole^?1NH₄⁺‐N) and on the exponential increase of the nitrogen loading rate (NLR, from 0.01 to 1.60 kg N m^?3 d^?1). 60 days after start‐up, anammox organisms were identified by polymerase chain reaction (PCR) technique as Candidatus Brocadia anammoxidans. After one year of operation, NLR had reached a value of 1.60 kg N m^?3 d^?1 with a nitrogen (ammonium plus nitrite) removal efficiency of 99.7%. The anammox biomass activity was verified by nitrogen mass balances with 1.32 ± 0.05 mole of nitrite removed per mole of ammonium removed and 0.23 ± 0.05 mole of nitrate produced per mole of ammonium removed. Also, enrichment of anammox bacteria was quantified by fluorescence in situ hybridization (FISH) analysis as 85.0 ± 1.8%. CONCLUSIONS: This paper provides a methodology for the enrichment of the anammox biomass in a SBR to treat high nitrogen loaded wastewaters. Copyright © 2007 Society of Chemical Industry     

SBR法低温短程硝化实现与稳定的中试研究

短程生物脱氮技术对于节省能源和碳源具有重要意义,而低温条件下实现短程硝化一直是制约该工艺推广的重要难题。以实际城市污水为研究对象,应用 54 m³的SBR中试系统重点研究了低温条件下短程硝化的实现途径和稳定方法。试验结果表明,通过对系统的硝化反硝化过程进行实时过程控制,并采用分段进水的运行模式,系统在温度为11.8～25℃的范围内均达到了稳定的短程脱氮效果,平均总氮去除率在９６％以上,平均亚硝化率在95%以上。长期的实时过程控制优化了系统的污泥种群结构,是低温中试SBR系统短程硝化实现与稳定的决定性因素。     

锅炉给水除氧技术新进展

锅炉给水除氧是防止热力系统腐蚀的重要方法。本文分析了常用的物理除氧和化学除氧的优缺点,介绍了当前除氧技术研究的最新进展,详细描述了触媒型钯树脂催化加氢除氧和光催化加氢除氧技术,并对除氧技术的发展加以展望。     

膜组件与膜反应器除氧技术的比较研究

除氧是工业用纯水生产过程中的重要步骤。针对传统物理除氧和化学除氧的缺点，提出了膜反应器除氧的技术，并从除氧效果及其原理两方面与膜组件除氧技术加以比较，结果发现膜反应器可采用物理和化学方法结合去除水中的溶解氧，其出水溶解氧含量显示出很好的水平。     

城市污水自养脱氮系统中有机物与磷的回收

厌氧氨氧化的发现使开发低能耗城市污水处理技术成为可能,可通过生物吸附实现污水能源与资源的回收。强化除磷系统污泥龄(SRT)仅为2 d,系统抗冲击性强,污泥沉降性良好,污泥体积指数(SVI)低于50,可为自养脱氮系统提供稳定的进水,但系统污泥碳含量仅为37%。将反应器内好氧水力停留时间(HRT)降至 40 min后,实现有机物去除序批式反应器(SBR)的稳定运行,厌氧段COD去除率占总COD去除率的93.8%,这表明系统对有机物的去除主要为生物吸附作用,同时污泥碳含量提升至48%。由于异养菌对有机物的消耗利用与除磷菌的吸磷过程同时进行,若试验废水C/P比较低,可降低系统水力停留时间、提升碳的回收率并辅助少量的化学除磷手段,对系统厌氧搅拌时间、曝气时间及污泥龄进行优化,从而实现C与P的高效回收。     

高溶解氧环境下好氧亚硝化颗粒污泥短程硝化特性研究

研究好氧亚硝化颗粒污泥的快速形成及在高溶解氧环境下好氧亚硝化颗粒污泥的短程硝化特性。采用SBR反应器,在偏碱性、高溶解氧条件下,以好氧颗粒污泥和具有硝化功能的活性污泥为种泥驯化培养,分析好氧亚硝化颗粒污泥形成机理及对亚硝酸盐的积累能力。研究结果表明:12d可形成具有氨氮平均去除率97%、最高亚硝化率70%的好氧亚硝化颗粒污泥,反应器能持续稳定运行;溶解氧高低对好氧亚硝化颗粒污泥的亚硝化率影响不大。说明此方法能够快速形成具有高亚硝酸盐积累率的好氧亚硝化颗粒污泥。     

针铁矿促进剩余污泥厌氧消化中的脱氮除碳

剩余污泥厌氧消化因其较低的能源转化率使其发展有所受限,且污泥中高浓度有机质也会影响脱氮效果。理论上,在含铁(Ⅲ)（氢）氧化物的厌氧消化系统中,微生物能通过异化铁还原去除有机物和氨氮（Feammox）,但两者同步去除还有待验证。因此本研究通过向污泥厌氧消化系统中添加针铁矿,探究铁(Ⅲ)（氢）氧化物对同步脱氮除碳的影响。结果显示,随着针铁矿添加量的增加,反应器中有机物浓度逐渐减少。当添加50mmol/L针铁矿时,甲烷累积产量达到695.1mL,相较于没有添加针铁矿的厌氧系统提升了30.3%;TS/VS去除率也提升了21.1%/33.8%,说明针铁矿可有效促进污泥减量化。添加针铁矿的反应器中总氮去除率也有一定提升,当针铁矿添加50mmol/L时,去除率达到21.0%。以上结果表明,添加针铁矿可以在污泥厌氧消化中起到同时脱氮除碳的效果。     

Start up of a pilot scale aerobic granular reactor for organic matter and nitrogen removal

Aerobic granulation is a promising technology for the removal of nutrients in wastewater. Since research to date is mainly focused at laboratory scale, a pilot‐scale sequencing batch reactor (100 L) was operated to obtain granular sludge in aerobic conditions grown on acetate as organic carbon substrate. Selective pressure created by means of decreasing settling time and increasing organic loading rate (OLR) enhanced the formation of aerobic granular sludge. Granules appeared after 6 days and reached an average diameter around 3.5 mm. The settling velocity value should be higher than 11 m h^?1 in order to remove flocculent biomass. The reactor treated OLRs varying between 2.5 and 6.0 g COD L^?1 d^?1 reaching removal efficiencies around 96%, which demonstrates the high activity and the ability of the system to withstand high OLR. Nevertheless, a rapid increase in the OLR produced a loss of biomass in the reactor due to breakage of the granules. Copyright © 2011 Society of Chemical Industry     

Modified carbon nitride as an efficient adsorbent for ammonia nitrogen with low concentration

The adverse effects of excessive ammonia on aquatic ecosystem have provoked the development of efficient methods for its removal. Here, we present a thermal copolymerization of melamine and sodium hydrogen carbonate and successfully introduce oxygen groups into the structure of g-C₃N₄, which is applied to low-concentration ammonia removal. Oxygen groups are introduced into g-C₃N₄ and increase its surface electron negativity. When the initial concentration of ammonia nitrogen is 18.74 mg L⁻¹, the lowest concentration of it after adsorption is 1.43 mg L⁻¹, and the ammonia nitrogen removal efficiency is 92.3%. The main reason for our material high performance on adsorption ammonium may be ascribed to deprotonated carboxylic acid, which has the ability to adsorb positively charged ammonium ions.     

自养脱氮工艺有机物去除段与硝化段精确分离的实现与实时控制

为了实现城市污水处理过程中的节能降耗,提出了三段式城市污水自养脱氮工艺,阐述了除有机物SBR在整套工艺中的重要地位,探讨了不同曝气量与污泥浓度条件下,除有机物SBR中有机物的去除特征与规律。结果表明,在不同的曝气量及污泥浓度条件下,COD降解结束前NO₂^--N与NO₃^--N的浓度均低于0.1 mg·L^-1,反应器进入COD难降解阶段后,NO₂^--N与NO₃^--N的浓度快速提高,可以认为在除有机物SBR内有机物的去除和硝化过程是分步进行的,即先进行有机物的去除,而后进行硝化过程。DO曲线与pH曲线的突越点与除有机物过程的终点始终保持一致,可将其作为实时控制参数监测有机物的去除终点,对好氧曝气过程进行实时控制。     

脉冲式SBR法深度脱氮工艺及其控制

在采用脉冲式SBR法处理城镇生活污水时,通过考察硝化-投加原水-反硝化-硝化-投加乙醇-反硝化这一反复过程,探求了DO、ORP和pH的变化规律,发现这些控制变量与有机物的去除及脱氮(硝化与反硝化)处理过程中各指标之间有很好的相关性.通过改变进水方式和进水量,充分利用原水中有机碳源,减少曝气时间,尽可能减少外碳源的投加量,既可以降低运行成本,又可以严格控制出水中的CODCr、氨氮和TN.结果表明,当进水CODCr在72.18～330.8 mg/L,NH4 -N在56.29～61.86 mg/L,在原水中反硝化碳源充足的情况下,采用脉冲式SBR法处理污水,反硝化结束时最终出水CODCr＜60mh/L,NH;-N＜0.92 ms/L,TN＜1.22 ms/L.     

Characterization of potentially bioreactive soil organic carbon and nitrogen by acid hydrolysis

Studies determined the potential of acid hydrolysis for estimating the bioreactive fraction of organic carbon in soils (SOC). Three soils (clay loam, silt loam, and sandy loam) were hydrolyzed with 1 M or 6 M HCl under reflux for up to 24 h. Results showed that 1.7 to 3.2 % of SOC could be liberated as CO₂ from the acid hydrolysis of soil. This readily hydrolyzed fraction should be a part of the bioreactive SOC. Higher amounts of soluble SOC and N as well as CO₂ were released from all soils by 6 M HCl than by 1 M HCl. Soluble SOC and N contents in both 1 M HCl and 6 M HCl hydrolysates of all soils increased rapidly during the initial 2 hours of hydrolysis, and then increased very gradually. The amounts of CO₂-C evolved correlated with the amounts of NH₄-N released during the acid hydrolysis (r = > 0.88). The ratio of SOC to soluble N was lower in 6 M HCl hydrolysate than in 1 M HCl. Hydrolysis of soil by 1 M HCl for 4 h appeared to be a promising approach for estimating the more bioreactive pools of SOC and N. This revised version was published online in August 2006 with corrections to the Cover Date.     

Simultaneous removal of TOC and TSS in swine wastewater using the partial nitritation process

BACKGROUND: Considering biological nitrogen removal, the partial nitritation connected with the anaerobic ammonium oxidation (anammox) process is a promising alternative for nitrogen elimination at high loading rates. The objective of the present study was to evaluate the establishment and operation of a partial nitritation process in an airlift reactor with simultaneous removal of total organic carbon and suspended solids using swine wastewater. RESULTS: The partial nitritation reactor was inoculated with a nitrifying sludge at 2.1 gTSS L^?1 and fed with an UASB reactor effluent. High organic carbon loading rates, above 2 kgTOC m^?3 d^?1 have been shown to be potential inhibitors of the partial nitritation process due to competition between autotrophic and heterotrophic bacteria. In this study, the partial nitritation process was established using undiluted swine wastewater, with HRT of 24 h, 1.84 mgO₂ L^?1 (SD = 0.41) DO, loading rate of 1.14 gTOC L^?1 d^?1 and 0.91 gN‐NH₃ L^?1 d^?1 for more than 100 consecutive days. At the same time, the system proved to be an effective tool in TOC and TSS removal, reaching 84.9% (SD = 9.3) and 83.1% (SD = 0.1), respectively. CONCLUSION: This result enhances partial nitritation application as a technology for high load nitrogen converting, and allows the possibility of connection with anammox reactors. Copyright © 2012 Society of Chemical Industry