Performance of Anammox granular sludge bed reactor started up with nitrifying granular sludge

The anaerobic ammonia oxidation(Anammox) granular sludge bed reactor was started up successfully with nitrifying granular sludge. During the operation, the nitrifying granular sludge was gradually converted into Anammox granular sludge with good settling property and high conversion activity. The Anammox reactor worked well with the shortest HRT of 2 43 h. Under the condition that HRT w as 6 39 h and influent concentration of ammonia and nitrite was 10 mmol/L, the removal of ammonia and nitrite was 97 17% and 100 00%, respectively. Corresponding volumetric total nitrogen loading rate and volumetric total nitrogen conversion rate were 100 83 mmol/(L·d) and 98 95 mmol/(L·d). The performance of Anammox reactor was efficient and stable.

Design and study on hydraulics characteristic of multistage anaerobic granular sludge reactor

This article provides some ideas about several key parameters in design of multistage anaerobic granular sludge reactor （MA（iSR）, and an MAGSR was designed by these ideas. By experiment this paper studies the productivity of biogas and circulation flux of wastewater. The results indicate that in certain scope the circulation flux increases in linear with the biogas productivity rise. The result by the experiment and by the hydraulics model about the circulation flux is different. The circulation flux can be several or more than ten times of the influence.

Experimental Study on Granular Sludge Cultivation Based on IC Reactor

[Objective]We aimed to discuss the optimal conditions of sludge granulation on the basis of IC reactor.[Method]By using the formulated glucose wastewater,we studied the rapid cultivation of granular sludge as well as its influencing factors,so as to discuss the optimal conditions of sludge granulation.[Result]Through the static culture outside of IC reactor and dynamic culture in IC reactor,granular sludge appeared within a training cycle,with particle size of 1.0-1.5 mm.In IC reactor,when COD concentration of influent water was 5 000 mg /L,rising velocity was 0.9 m /h,pH was around 7,and auxiliary materials (like flocculant and active carbon) and mature granular sludge were added to the actor during the training process,the granulation process of sludge was accelerated.[Conclusion]The research could provide references for the rapid start-up of IC reactor.

Development of a novel modified EGSB reactor for municipal sewage treatment at ambient temperatures

A novel modified expanded granular sludge bed(EGSBm) reactor was developed for anaerobic treatment of municipal sewage with mixed liquid recirculation instead of effluent recirculation commonly adopted by a conventional EGSB(EGSBc) reactor.Performances of these two reactors were compared in treating municipal sewage at ambient temperatures ranging from 8 to 26 ℃.At an upflow liquid velocity(Vup) of 10.3 m/h,the mean concentrations of filtrated COD(CODfilt) and COD of the EGSBm effluent were determined to be 59.4 and 95.9 mg/L,respectively,which were significantly lower than those of the EGSBc effluent operated under identical experimental conditions.When the organic loading rate was suddenly increased from 1.2 to 7.2 kg COD/(m3·d),the EGSBm regained the removal efficiency of previous operation phase in 10 d.Hydrodynamic characteristics of the reactors were compared using the residence time distribution(RTD) model.It was found that the treatment efficiency of EGSBm kept increasing as the Vup increased.The polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis(PCR-DGGE) technique was used to analyze the microbial diversity in EGSBm.Fingerprinting pattern indicated that some species in the inoculating sludge were still reserved in the granular sludge of EGSBm,moreover,several new species occurred.

Effect of inorganic carbon on anaerobic ammonium oxidation enriched in sequencing batch reactor

The present lab-scale research reveals the enrichment of anaerobic ammonium oxidation microorganism from methanogenic anaerobic granular sludge and the effect of inorganic carbon(sodium bicarbonate)on anaerobic ammonium oxidation.The enrichment of anammox bacteria was carried out in a 7.0-L sequencing batch reactor(SBR)and the effect of bicarbonate on anammox was conducted in a 3.0-L SBR.Research results,especially the biomass,showed first signs of anammox activity after 54 d cultivation with synthetic wast...

Treatment of methanol wastewater in external circulation anaerobic reactor with different inoculums

In order to guide the inoculums selection for the anaerobic treatment of methanol wastewater in the engineering application,two 7 L bench-scale external circulation (EC) anaerobic reactors were operated to investigate the inoculums of anaerobic granular sludge and anaerobic digested sludge,focusing on the efficiency and process stability.The effect of impact concentration and temperature on the performance was studied.The results demonstrated that anaerobic granular sludge as the inoculums could complete the start-up more rapidly than the anaerobic digested sludge,and above 90% COD removal were achieved at the organic loading rate of 10 to 15 kgCOD/(m3·d).The effect of impact COD on the methanogenic activity of sludge was weak and the removal efficiencies recovered gradually in the two reactors.The COD removal efficiencies reduced swiftly to 50%-60% due to the impact temperature.The results indicated that the complex bacterial groups in anaerobic digested sludge benefited to enhance the reactor's capacity for withstanding the temperature shock at some extent.

Anaerobic hydrogen production of molasses from mixed microbial communities immobilized by activated granular carbon

Molasses wastewater was evaluated as substrate for biohydrogen production by anaerobic fermentation in a novel continuous mixed attached growth reactor ( CMAGR ) with aeration pretreated sludge attached onto granular activated carbon under continuous flow condition.It was indicated that the CMAGR system was operated at the conditions of influent COD of 2000～6000mg / L , hydraulic retention time ( HRT ) of 6hand temperature of 35 ℃ , when the pH value and oxidation-reduction potential ( ORP ) ranged from 4.16and-434 mV respectively , stable ethanol-type fermentation was formed with the sum of ethanol and acetate concentration ratio of 89.3%to the total liquid products after 40days operation.The H 2 content in biogas and chemical oxygen demand ( COD ) removal were estimated to be 46.6% and 13% , respectively.It was also investigated that the effects of organic loading rates ( OLRs ) on CMAGR hydrogen production system.It was found that hydrogen production yield increased from 3.72 mmol / hL to 12.51 mmol / hL as OLRs increased from 8 kg / m 3 d to 32 kg / m 3 d.The maximum hydrogen production rate of 12.51mmol / hL at a OLR of 32kg / m 3 d and the maximum hydrogen yield by substrate consumed was 130.57 mmol / mol happened at OLR of 16 kg / m 3 d.Greater pHs appeared to be favour to butyrate production and the maximum of 0.51mol / mol was obtained at pH of 4.14.However , ethanol / acetate ratio was greater than 1.1at pH fluctuated between 3.4 - 3.6and 4.1 - 4.4which indicated that these pHs were favour to ethanol type fermentation.Therefore , the continuous mixed attached growth reactor ( CMAGR ) could be a promising attached growth system for biohydrogen fermentation.

Quick start-up of EGSB reactor treating fresh leachate of municipal solid waste

An expanded granular sludge bed （EGSB） reactor inoculated with anaerobic granular sludge was started up with its COD removal performance, self-balancing of pH, biogas production rate and characteristics of the granular sludge during the start-up period being investigated. The results indicated that the EGSB reactor can be started up successfully in 27 d by increasing the organic loading rate rapidly. The removal efficiency of COD was maintained above 93% with influent COD concentration of 25 000 mg/L and OLR of 37.94 kgCOD/（m 3 ·d）. The EGSB reactor with good pH self-balancing could be fed with fresh leachate of low pH value （4 5）. The biogas production rate was closely related with OLR and COD reduction. Every gram of COD fed （consumed） to the reactor produced 0.34 L STP （0.36 L STP ） biogas with 0.21 L STP （0.23 L STP ） methane. Thus, 65% 70% of the produced biogas was methane. Sixty one percentage of COD fed to the reactor was converted to methane, another 33% was converted to biomass by metabolism, and the other 6% was left in the liquid phase. The specific methanogenic activity （SMA） of the granular sludge had increased by 92% after 27 d dynamic incubation. The granular sludge in the reactor had good settlement performance with majority diameter of 1 2 mm.

Population dynamics on anaerobic sludge granulation in UASB reactors

Three UASB reactors were operated to investigate the population dynamics of anaerobic sludge granulation. It is found that the increase of bacterial population relates to the bacterial status in anaerobic food chain and relates to sludge organic loading rates. In order to form granular sludge, it is necessary to have sufficient amount of different groups of bacteria in the sludge. In our experiment, the population of fermentative bacteria, propionate degraders, butyrate degraders and methanogens is about 107-8, 105-7, 105-7 and 105-7 cells/ml respectively at the appearance of granular sludge. Filamentous methanogenic bacteria are found to be the important species in sludge granulation. Based on the results obtained, a descriptive model is proposed to describe the microbial characteristics of granulation.

Anaerobic tapered fluidized bed reactor for starch wastewater treatment and modeling using multilayer perceptron neural network

treatability of synthetic sago wastewater was investigated in a laboratory anaerobic tapered fluidized bed reactor （ATFBR） with a mesoporous granular activated carbon （GAC） as a support material. The experimental protocol was defined to examine the effect of the maximum organic loading rate （OLR）, hydraulic retention time （HRT）, the efficiency of the reactor and to report on its steady- state performance. The reactor was subjected to a steady-state operation over a range of OLR up to 85.44 kg COD/（m^3·d）. The COD removal efficiency was found to be 92% in the reactor while the biogas produced in the digester reached 25.38 m^3/（m^3·d） of the reactor. With the increase of OLR from 83.7 kg COD/（m^3·d）, the COD removal efficiency decreased. Also an artificial neural network （ANN） model using multilayer perceptron （MLP） has been developed for a system of two input variable and five output dependent variables. For the training of the input-output data, the experimental values obtained have been used. The output parameters predicted have been found to be much closer to the corresponding experimental ones and the model was validated for 30% of the untrained data. The mean square error （MSE） was found to be only 0.0146.

废水处理硝酸盐异化还原与厌氧氨氧化/反硝化耦合工艺构建

采用厌氧膨胀颗粒污泥床反应器(EGSB)处理含COD、氨氮和硝氮的模拟废水,旨在高浓度有机废水处理系统中快速构建厌氧氨氧化(Anammox)运行工艺。通过接种少量Anammox污泥和逐步提高氨氮浓度的操作方式,在连续运行58d后,系统成功启动Anammox反应,此时的总氮和COD去除率稳定在97%和98%以上。物料衡算显示,Anammox反应途径对氮的去除贡献逐渐增加,硝酸盐异化还原(DNRA)耦合Anammox和反硝化共同促进了系统的同步脱氮除碳。对微生物群落分析发现,Candidatus Kuenenia相对丰度由0.27%快速升高至35.87%,DNRA菌(Ignavibacterium、Thermogutta)及反硝化菌(Azospira、Gp3)在体系内共存。通过基因注释法,检测出了Anammox、DNRA、硝酸盐还原及亚硝酸盐还原关键基因。运行过程中,颗粒污泥颜色变红且粒径增大;胞外聚合物(EPS)分析表明多糖(PS)和蛋白质(PN)含量增加而PN/PS下降;三维荧光光谱发现腐殖酸类物质增多。研究结果为高浓度有机含氮废水高效处理提供了一种新的工艺途径。

好氧颗粒污泥快速成粒的影响因素及在连续流反应器研究进展

从水力选择压、交替的盛宴-饥荒期间、接种污泥种类、微生物生长基质组成4个方面综述了影响好氧颗粒污泥的快速成粒因素。并结合以上因素综述了基于连续流反应器的好氧颗粒污泥培养的研究进展。介绍了现有AGS研究的局限性并对未来发展方向提出建议。

Ni^(2+)诱导好氧颗粒污泥形成及处理高盐废水脱氮除磷研究

南疆地区的土壤表层含盐量大,漫灌用水引起盐分溶解,污染地表水,研究降解高盐废水脱氮除磷的技术尤为重要。在高径比(R_(H/D))为7.5的序批式间歇反应器(SBR)内接种活性污泥,以合成废水(含0.25 mg/L Ni^(2+))为进水,分析污泥颗粒化过程中的污泥形态、污染物去除性能、微生物群落的变化,以及盐度胁迫下颗粒污泥去除高盐废水中污染物的能力。结果表明,成熟的颗粒污泥呈黄色多元状,平均粒径为357μm,对废水中COD、TP和NH_(4)^(+)-N的平均去除率分别为95%、91.27%和94.5%,优势菌属为动胶菌属(Zoogloea)、黄杆菌属(Flavobacterium)和Unclassi⁃fied_f_Comamonadaceae,进水水质会改变微生物的相对丰度,而对菌群结构无明显影响;NaCl投加量为15 g/L时,COD、TP和NH_(4)^(+)-N去除率分别为86.7%、67.2%和62.6%,污泥保持良好的除碳能力,NaCl投加量超过15 g/L时,各指标的去除率均呈下降趋势。投加低浓度的重金属,加速了颗粒污泥的启动,并靶向选择脱氮除磷的微生物,对高盐废水中污染物的处理具有借鉴意义。

溶解氧浓度对好氧颗粒污泥形成及微生物群落演变的影响

曝气头深度与系统内的溶解氧(DO)浓度有关,而DO浓度对好氧颗粒污泥中微生物处理废水性能具有重要意义。采用高径比为7.5的序批式反应器(SBR)C0~C3,内接冷藏颗粒污泥,进水为混合废水,以SBR底部为起点曝气头分别设置在SBR的0H(有效高度简写为H)、1/3H、1/2H和H处,产生的DO分别为3、4、5、6 mg/L,分析SBR系统中污泥特性、污染物去除性能及微生物群落的动态变化规律。结果表明:60 d时,C0~C3中颗粒污泥中值粒径分别为952、1 325、1 020、725μm,悬浮固体质量浓度分别为3.99、6.74、3.18、6.90 g/L,胞外聚合物质量浓度分别为125.12、135.14、128.05、114.81 mg/g;对污水中COD、氨氮、总磷平均去除率均高达79%、74%和65%以上;富集了具有固氮的拜叶林克氏菌属(Beijerinckia)、脱氮的丛毛单胞菌属(Comamonas)和降解芳香烃的新鞘氨醇菌属(Novosphingobium)。通过调控曝气头深度,实现了不同功能微生物的富集,对好氧颗粒污泥的稳定运行有实际应用价值。

三维电极反应器电吸附深度处理含砷废水

水环境中砷的深度处理对减少环境污染和确保人类健康至关重要。自制了三维电极反应器,以活性炭颗粒为粒子电极材料,采用电吸附和物理/化学吸附联合模式实现As(Ⅴ)的深度处理。经优化后,As(Ⅴ)浓度可从0.5 mg/L降至0.032 mg/L,且均以H_(2)AsO_(4)-形式存在,无As(Ⅲ),表明不存在氧化还原反应。动力学研究发现,电吸附过程可分为三步:从溶液到电极材料表面的液膜扩散过程、从电极材料表面到内部孔隙的内扩散过程和电吸附接近平衡状态。为验证该工艺的循环性能,开展了电吸附-电脱附工艺研究,发现经过8次循环后,出水浓度仍仅为0.098 mg/L(低于0.1 mg/L的标准限值),实现了含砷废水的高效深度处理,但去除效率需提升、吸附后材料的处理仍需改进。

IC厌氧反应器处理OCC废水运行效率研究

某OCC制浆造纸企业新建了一座容积2900 m^(3)的IC厌氧反应器,并引入来自同类废水的厌氧颗粒污泥。启动21天后,IC厌氧反应器运行效果达到设计负荷,OCC制浆造纸废水处理量为15000 m^(3)/d,CODCr处理量为50000 kg/d,CODCr去除率72%~86%,出水挥发性脂肪酸稳定保持在30~110 mg/L,IC厌氧反应器在较短时间内完成效率提升。

好氧颗粒污泥处理低氨氮废水短程硝化研究

采用现有的好氧颗粒污泥,通过在序批式反应器(sequencing batch reactor,SBR)中接种颗粒污泥,基于人工模拟废水,研究好氧颗粒污泥处理低氨氮污水,实现短程硝化。结果表明,短程硝化效果受到有机物浓度、pH、氨氮浓度、排水比等因素的影响,当SBR反应器进水NH_(4)^(+)-N浓度为55mg/L左右时,NH_(4)^(+)-N去除率达到97.1%,亚硝酸盐氮积累率(Nitrite Accumulation Rate,NAR)达到95%,TN去除率达到35%以上,表明SBR反应器能够实现稳定的短程硝化效果。

连续流反应器中好氧颗粒污泥快速培养研究进展

好氧颗粒污泥(aerobic granular sludge,AGS)是目前最有前景的污水生物处理技术之一,采用连续流反应器(continuous flow reactor,CFR)进行AGS快速培养的技术近年来受到广泛关注。文中通过综述间歇式反应器(sequencing batch reactor,SBR)工艺实现快速颗粒化的调控方法、CFR强化颗粒化及优化控制,总结了目前SBR工艺实现快速颗粒化的主要措施,以及采用基于SBR颗粒化的原理在CFR中实现快速颗粒化的可行方案,包括选择压优化、饱食/饥饿(feast/famine)条件以及晶核策略(crystal nucleus)等。最后对CFR工艺实现快速颗粒化的应用前景进行了展望,并提出探究SBR中强化颗粒化的策略,将有望在未来更加深入地研究AGS在CFR中的形成机理。

低基质条件下厌氧氨氧化生物膜和颗粒污泥脱氮性能对比研究

在低基质质量浓度条件下,对海绵填料生物膜反应器和颗粒污泥反应器进行厌氧氨氧化的脱氮性能进行对比研究。研究结果表明:当进水NH4+-N和NO2--N质量浓度分别为(17.03±2.16)mg/L和(19.17±2.33)mg/L时,颗粒污泥厌氧氨氧化反应器的脱氮性能明显优于海绵填料生物膜反应器的脱氮性能;保持对NH4+-N和NO2--N的平均去除率为90%以上时,通过缩短水力停留时间,颗粒污泥反应器容积氮去除速率可达3.55 kg.N/(m3·d),而海绵填料生物膜反应器仅为0.94 kg·N/(m3·d);进水中NO2--N与NH4+-N的质量浓度比能影响反应器的化学计量关系。

林可霉素生产废水的厌氧生物处理工艺

采用单相中温升流式厌氧污泥床 (UASB)反应器厌氧生物工艺处理含有有毒难降解有机物的林可霉素生产废水 .当进水COD 80 0 0～ 1 4 0 0 0mg/L ,HRT约 1 0h时 ,COD容积负荷可达 2 0～ 35kg/(m3·d) ,COD去除率为50 %～ 55% .适时调整并维持较高的表面水力负荷 [0 .2～ 0 4m3/(m2 ·h) ]、较高的进水有机基质浓度 (COD为2 0 0 0～ 30 0 0mg/L)和污泥COD负荷 [0 2～ 0 5kg/(kg·d) ],并适当延长启动驯化时间可培养出沉降性好、污泥活性较高的颗粒污泥 .废水厌氧生物降解动力学符合Monod方程 ,动力学常数Vmax=1 3d- 1,Ks=81 33mg/L .废水中不可生物降解物质占总COD的比例约为 30 % ,这是废水COD去除率偏低的重要因素 .