淹没式MBR处理啤酒废水的净化效能研究

在投加营养物质,保持COD:TN:TP=100:5:1的条件下,淹没式MBR对啤酒废水中的COD、NH 4-N有着较好的去除效果,系统稳定时COD与NH 4-N的平均去除率均在90%以上,而且MBR工艺对进水有机负荷的冲击具有较强的短时适应能力,当COD污泥负荷由0.27g/g·d突然增加至0.54g/g·d时,出水COD浓度未出现明显的波动。通过GC/MS分析得出,膜组件出水中剩余的有机物主要为高分子量的烷烃类,膜组件对于保证系统的最终出水水质起到了关键的作用。     

A novel nearly plug‐flow membrane bioreactor for enhanced biological nutrient removal

The feasibility of enhanced biological nutrient removal by a new process called nearly plug‐flow membrane bioreactor (NPFMBR) is studied. Results of long‐term observations showed that average removal degrees of (1) chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) reached 95%, 85%, and 89%, respectively, at the steady operation period. Process success was further corroborated by batch experiments. Data of specific oxygen uptake rates demonstrated the abundance and/or high activities of ammonium oxidation bacteria and nitrite oxidation bacteria in the sludge. Observed specific rates of nitrification, denitrification, phosphorous release/uptake of the sludge were higher than those reported in previous research. Because of the unique flow pattern of sludge and alternant aerobic–anoxic operating conditions in the bioreactor, mass transfer and biotransformation of nutrients were expected to be improved. The NPFMBR could offer a new option for the wider application of MBRs. © 2012 American Institute of Chemical Engineers AIChE J, 59: 46–54, 2013     

SRT对膜生物反应器（MBR）的污泥活性和硝化性能的影响

考察了SRT分别为10 d和不排泥2种情况下MBR的运行效果和污泥特征的变化,研究结果表明,随着SRT的减小,比耗氧速率从不排泥时的10.2 mg O2/g SSh增加至SRT为10 d时的15.9 mg O2/g SSh,排泥有助于提高污泥的活性。不排泥运行和SRT为15 d两种情况的处理效果基本相同,去除效率均超过90%,继续提高氨氮负荷,M2出水NH4-N浓度增加,因此污泥停留时间应该根据不同的水质来设定。     

壳聚糖投加对MBR污泥混合液性质及膜污染的影响

通过试验研究了壳聚糖投加对膜一生物反应器中污泥混合液的颗粒粒径、污泥粘度、污泥脱水性能,溶解性微生物产物（SMP）及胞外聚合物（EPS）的影响。探讨了投加壳聚糖减缓膜污染的原因。结果表明投加壳聚糖提高了反应器对COD、TN、TP及NH3-N的去除效果。投加壳聚糖能够降低混合液粘度,增大污泥粒径,使污泥比阻值下降约80％。提高了污泥脱水性能,并降低了反应器中SMP的含量,从而降低了膜污染速率。     

MBR和BAF用于城市污水深度处理的工艺特性比较

采用膜生物反应器(MBR)和曝气生物滤池(BAF)2种工艺分别对以生活污水为主的城市污水进行深度处理,以达到污水回用的目的.中试结果表明,在平均水温仅为5℃的情况下,MBR工艺的处理效果明显优于BAF,MBR_4~+工艺对COD、BOD＿5、NH_4~+-N和TP的去除率分别可以达到75%、92%、95%和90%,,而BAF对COD、BOD_5、NH_4~+_N和TP的去除率仅为70%、78%、29%和82%.经核算,MBR和BAF的污水处理运行费用分别为0.82元·m~(-3)和0.55元·m~(-3).与BAF相比,MBR具有处理效果优良、出水稳定、占地面积少,且维护管理方便等特点,因此,在以污水回用为目的的实际工程中推荐采用MBR工艺.     

Biological Nutrient Removal in a Full Scale Anoxic/Anaerobic/Aerobic/ Pre-anoxic-MBR Plant for Low C/N Ratio Municipal Wastewater Treatment

A novel full scale modified A2O （anoxic/anaerobic/aerobic/pre-anoxic）-membrane bioreactor （MBR） plant combined with the step feed strategy was operated to improve the biological nutrient removal （BNR） from low C/N ratio municipal wastewater in Southern China. Transformation of organic carbon, nitrogen and phosphorus, and membrane fouling were investigated. Experimental results for over four months demonstrated good efficiencies for chemical oxygen demand （COD） and NH4^＋-N removal, with average values higher than 84.5%and 98.1%, re-spectively. A relatively higher total nitrogen （TN） removal efficiency （52.1%） was also obtained at low C/N ratio of 3.82, contributed by the configuration modification （anoxic zone before anaerobic zone） and the step feed with a distribution ratio of 1：1. Addition of sodium acetate into the anoxic zone as the external carbon source, with a theoretical amount of 31.3 mg COD per liter in influent, enhanced denitrification and the TN removal efficiency in-creased to 74.9%. Moreover, the total phosphate （TP） removal efficiency increased by 18.0%. It is suggested that the external carbon source is needed to improve the BNR performance in treating low C/N ratio municipal waste-water in the modified A^2O-MBR process.     

不同污泥龄下MBBR-MBR和MBR的脱酚脱氮性能比较

通过平行运行MBBR-MBR和MBR,保持进水水质和其他操作条件相同的条件下,对比两个反应器在不同污泥龄下对NH3-N、COD、TN和间甲酚的降解效率,分析MBBR－MBR和MBR各自的脱酚脱氮性能。试验表明：不同污泥龄下MBBR—MBR的处理效率均。蒋于MBR。当污泥龄为8d时,MBBR－MBR对NH3-N的去除效率是MBR的2．4倍：当污泥龄为20d时,MBBR－MBR对NH3－N、TN、COD、间甲酚的去除效率分别为95．4％、82．6％、99．4％和99．6％。     

The effect of COD/N ratio on process performance and membrane fouling in a submerged bioreactor

Influent chemical oxygen demand/nitrogen (COD/N) ratio is used to control fouling in membrane bioreactor (MBR) systems. However, COD/N also affects the physicochemical and biological properties of MBR biomass. The current study examined the relationship between COD/N ratio in feed wastewater and extracellular polymeric substances (EPS) production in MBRs. Two identical submerged MBRs with different COD/N ratios of 10:1 and 5:1 were operated in parallel. The cation concentration and floc-size of the sludge were measured. The composition and characteristics of bound EPS and soluble microbial products (SMP) under each COD/N ratio were also examined. Batch tests were conducted in 1000 mL bottles to study the process of the release of foulants from the sludge when 1 g of (NH₄⁺-N)/L was added. Results showed that the influent COD/N ratio could change the physicochemical properties of EPS and SMP. Moreover, excessive NH₄⁺ in the supernatant could facilitate the role of NH₄⁺ as a monovalent cation, the replacement of the polyvalent cation in bound EPS, and even the extraction of EPS components from the surface of the sludge to form new SMP.     

Comparison of removal of pharmaceuticals in MBR and activated sludge systems

Membrane bioreactors (MBRs) nowadays attract serious attention for the treatment of municipal wastewater, due to recent technical innovations and drastic cost reductions of the employed membranes. Especially the high biomass concentrations and long sludge retention times are favorable for the biodegradation of organic pollutants, resulting in high rate treatment systems. These characteristic features of MBR technology are not merely advantageous for organic matter removal, but also likely promote a higher biodegradation efficiency of refractory organic pollutants. The increasing concern about the potential accumulation of micro-pollutants such as pesticides, pharmaceuticals and personal care products, in the aquatic environment triggered many investigations into their biological degradation or fate in wastewater treatment systems. In this work a short overview is presented on the current knowledge of removal of pharmaceuticals in MBRs compared to their removal in conventional activated sludge treatment system. In general, for slowly degradable pharmaceuticals the removal in MBRs is better due to the relatively long sludge ages, which leads to the development of distinct microbial communities in MBRs compared to activated sludge plants. Nevertheless, from the literature results it could not be concluded that pharmaceutical removal in MBR reactors is better as many other factors have been indicated that may affect biodegradation rates, which are not directly related to the reactor configuration.     

改良UCT分段进水脱氮除磷工艺性能及物料平衡

采用改良UCT分段进水试验装置研究了该工艺处理实际生活废水的脱氮除磷性能,建立了该系统碳(COD)、氮、磷的物料衡算公式,并以稳态条件下试验数据为基础分析评价了各指标的物料分布情况。结果表明,工艺出水水质稳定,抗冲击负荷能力较强,平均出水COD、总氮、总磷含量分别为43.5、8.51、0.29mg·mL-1,满足国家城镇生活污水一级A排放标准。此外,根据建立的物料衡算公式及工艺各反应区污染物指标的转化途径分析发现,高达67.1%的反硝化脱氮作用(包括缺氧反硝化和好氧同步硝化反硝化)是该工艺深度脱氮的根本原因;系统反硝化和释磷过程利用的COD占总去除量的62.1%,体现了该工艺充分利用原水碳源的优势;氮素和COD的平衡率均高达99.8%,证明了所建立的公式的有效性。系统对磷的去除主要依赖于排放的剩余污泥,占总量的71.7%。     

AO工艺同步脱氮除磷效能的研究

采用A／O同步脱氮除磷工艺处理模拟污水,调整DO、HRT、内回流、进水污染物的浓度等影响因素,考察了该工艺单位活性污泥处理污水中TN、TP的能力。结果表明,当好氧区DO控制在0．6mg／L左右,HRT控制在10h,内回流比控制在1：1时,单位活性污泥处理污水TN、TP的能力最强,单位活性污泥TN去除速率达到14×10^-3mg／（L·mg MLVSS·h）,单位活性污泥TP去除速率达到0．14×10^-3mg／（L·mg MLVSS·h）,AO系统实现了同步硝化反硝化和反硝化除磷。     

SRT对膜生物反应器出水水质的影响及其控制途径的研究

膜生物反应器中MLVSS为4000-5000mg／L时,COD的去除率可达98％左右,但随SRT的继续延长,污泥浓度的增加,使得内源呼吸加剧和大量微生物死亡,导致上清液COD上升,SMPnd含量增加,出水COD存在波动性,但COD的去除率仍在94％左右。高污泥浓度下的MBR反应器中投加粉末活性炭后,由于粉末活性炭对SMPnd有很强的吸附作用,因此反应器对COD的去除率增加。     

污泥浓度对MBR净化效果影响试验研究

在不排泥条件下,膜生物反应器(MBR)内的污泥浓度MLSS和MLVSS都随时间不断累积,而反映污泥活性的MLVSS/MLSS则不断减少。研究中发现,MLSS对MBR运行效果影响显著:TN的去除率随污泥浓度增加而增加,而COD的去除率随MLSS的增加先降后升,TP的去除率则先升后降,且二者均在污泥浓度6500 mg/L时达到极值,NH3-N的去除效果则随着污泥负荷的增加呈降低趋势。     

多点进水改良型复合A2/O处理低C/N污水

以低C/N比城市生活污水为研究对象,重点考查了改良A²/O工艺的脱氮除磷性能。原水按一定比例分配给厌氧池和缺氧池,以合理分配厌氧释磷和缺氧反硝化所需的碳源;在好氧池和缺氧池中分别投加填料,以稳定系统的硝化和反硝化效果,提高系统的脱氮性能;厌氧池和缺氧池出水都直接进入好氧池。在进水COD/TN平均为5.54,HRT为11 h,SRT为15 d,MLSS为3000～4000 mg·L^-1,污泥回流比为50%条件下,通过三种不同进水分配比以及三种混合液回流比的对比试验研究,得到系统最佳进水分配比5:5,对分配脱氮和除磷所需碳源更加合理;而混合液回流比为200%,过高会破坏缺氧池的溶解氧环境,过低又会导致缺氧池反硝化作用不能充分发挥。在最优工况下COD、NH₃-N、TN和TP出水水质分别为29.7、0.1、11.8和0.42 mg·L^-1,平均去除率分别达到87.8%、99.7%、72.4%和91.3%,出水优于国家GB 18918-2002一级A排放标准,并且在缺氧池中发生了明显的反硝化除磷现象。     

宾馆生活污水的脱氮除磷

在克服常规脱氮除磷与反硝化除磷技术缺点的基础上将两者优势结合起来,设计了具有一个主反应池和两个较小污泥池的双泥SBR新工艺。处理臬宾馆实际生活污水,试验结果表明：COD、TN和TP的去除率达到90％、82％、93％,出水水质指标满足现行的《城镇污水处理厂污染物排放标准》（GB18918．2002）一级标准的要求。同时讨论了DO、污泥龄对系统运行的影响。     

流化床式MBR在高MLSS下污水处理研究

研究了高溶液悬浮固体浓度（MLSS）下流化床膜生物反应器污水处理的有关特性。实验结果表明,当MLSS为20～25g／L、填料填充率为59／6时,控制溶解氧（DO）为0．5～1．0mg／L、C／N为4～6、水力停留时间为4h,MBR工艺可实现很好的脱氮以及COD去除效果。在长期的实验中发现,此类型MBR在高MLSS有较好的耐冲击负荷能力、抗污染能力以及低污泥产率。     

污水处理厂提标改造工程深度处理方案

武汉某污水处理厂提标改造工程,将出水水质由现状一级A标准提升至接近地表Ⅲ类水标准(TN≤10 mg/L),经复核,采用"强化现状处理设施处理功能+新建深度处理单元"的方案.根据案例分析:深度脱氮单元采用反硝化深床滤池或MBR工艺;深度降解COD单元采用臭氧接触氧化工艺或活性炭吸附工艺.通过对"反硝化深床滤池工艺+臭氧接...     

Membrane bioreactor technology for wastewater treatment and reuse

Treatment technology for water recycling encompasses a vast number of options. Membrane processes are regarded as key elements of advanced wastewater reclamation and reuse schemes and are included in a number of prominent schemes world-wide, e.g. for artificial groundwater recharge, indirect potable reuse as well as for industrial process water production. Membrane bioreactors (MBRs) are a promising process combination of activated sludge treatment and membrane filtration for biomass retention. This paper will provide an overview of the status of membrane bioreactor applications in municipal wastewater reclamation and reuse in Europe and will depict their potential role in promoting more sustainable water use patterns. Particular attention will be paid to the impact of MBR technology on emerging pollutants. A case study will be presented on a full-scale MBR plant for municipal wastewater which is operated by Aquafin in Belgium.     

A Review of Membrane Fouling in MBRs: Characteristics and Role of Sludge Cake Formed on Membrane Surfaces

Abstract

Membrane bioreactor (MBR) has been deemed to be a promising technology for wastewater treatment and reclamation; however, the MBR filtration performance inevitably decreases with filtration time attributed to the deposition of soluble and particulate materials onto and into the membrane under the interactions between activated sludge components and the membrane. Cake layer formation on membrane surfaces has been a major challenge in the operation of MBRs under supra-critical flux operation, and/or caused by uneven distribution of aeration intensities, etc.; however, it was argued that a thin cake layer might improve filtration operation by some researchers. This paper provides a critical review on the formation mechanisms, properties, the role of sludge cake in membrane filtration, and the corresponding strategies of controlling cake fouling in MBRs. Drawbacks and benefits of the formation of sludge cake were also discussed in order to better understand the characteristics and role of sludge cake formation in MBRs.     

常规SBR反应柱中好氧污泥颗粒化及其特性

应用高径比为3.67的SBR反应柱R1培养好氧颗粒污泥,结果表明,经90 d培养即可获得粒径主要分布在0.5~1.0 mm、形状规则、结构密实的好氧颗粒污泥。R1中颗粒污泥MLSS为5 500 mg/L,SVI_(30)为36 m L/g,好氧颗粒污泥沉降性能明显优于常规活性污泥。应用培养的好氧颗粒污泥处理实际集成电路工业综合废水,废水COD、氨氮、TP和TN去除率分别在85%、80%、60%和47%以上。通过污泥产率分析得出,好氧颗粒污泥比活性污泥污泥原位减量41.5%。