Submerged Membrane Bioreactor for Vegetable Oil Wastewater Treatment

A bench‐scale submerged membrane bioreactor (SMBR) was employed to treat vegetable oil plant wastewater with complete sludge retention. Treatment performance and membrane fouling of the SMBR were investigated. The system stably removed high amounts of total organic carbon, oil, and ammonia from vegetable oil wastewater and reduced the chemical oxygen demand, demonstrating the great potential of the SMBR in removing pollutants. The membrane fouling layer was not only governed by deposition of organic substances composed of extracellular polymeric substances like proteins, polysaccharides etc., and oil substances but also by inorganic elements. Organic foulants coupled to inorganic precipitation enhanced the formation of a gel layer and triggered severe membrane fouling in the SMBR.     

Experimental Study and Design of a Submerged Membrane Distillation Bioreactor

A hybrid process incorporating membrane distillation in a submerged membrane bioreactor operated at elevated temperature is developed and experimentally demonstrated in this article. Since organic particles are rejected by an ‘evaporation’ mechanism, the retention time of non‐volatile soluble and small organics in the submerged membrane distillation bioreactor (MDBR) is independent of the hydraulic retention time (mainly water and volatiles). A high permeate quality can be obtained in the one‐step compact process. The submerged MD modules were designed for both flat‐sheet membranes and tubular membrane configurations. The process performance was preliminarily evaluated by the permeate flux stabilities. The module configuration design and air sparging used in the MDBR process were tested. Flux declines were observed for the thin flat‐sheet hydrophobic membranes. Tubular membrane modules provided more stable permeate fluxes probably due to the turbulent condition generated from air sparging injected inside the tubular membrane bundles. The experiments with the submerged tubular MD module gave stable fluxes of approximately 5 L/m² h over 2 weeks at a bioreactor temperature of 56 °C. The total organic carbon in the permeate was consistently lower than 0.7 mg/L for all experiments.     

Behavior of Membrane Scaling During Crossflow Filtration in the Anaerobic MBR System

Abstract

Fouling of membrane bioreactor (MBR) has been studied intensively. Because of the high concentration of carbonates, scaling can be a serious problem in anaerobic bioreactor, which attracts little attention. In this study, the wastewater was treated with an anaerobic process followed by either a submerged or a side‐stream aerobic membrane reactor. The wastewater was spiked with calcium to investigate the effect of scaling on membrane filtration. Very little scaling was detected in the external membrane system (the side‐stream MBR). Results from chemical cleaning of internal membrane system indicated that the flux decline caused by membrane scaling was far more severe than that by membrane fouling. However, the flux decline from membrane scaling can be effectively recovered by the chemical cleaning of EDTA and NaOCl.     

膜生物反应器膜污染的研究进展

从膜的结构性质、反应器操作条件、处理液微生物性质三个方面介绍了膜生物反应器膜污染机理研究的进展,总结了优化膜生物反应器设计、调节膜生物反应器操作条件、在线超声控制、化学方法等膜污染控制的常用方法,对未来膜污染研究进行了展望。     

Influence of Dissolved Organic Carbon and Suspension Viscosity on Membrane Fouling in Submerged Membrane Bioreactor

Abstract

This paper deals with the membrane fouling in membrane bioreactor (MBR). Based on the experimental data obtained in the MBR pilot plant study, the influence of F/M ratio on the irreversible and reversible fouling was discussed in the wide range of MLSS concentration. In the case of lower MLSS concentration (2,000–3,000 mg/L), irreversible fouling rate of membrane increased with increasing F/M ratio because of the accumulation of DOC in the mixed liquor. It seems that soluble microbial products with the similar size of the membrane pore will be most responsible for the irreversible fouling. In the case of higher MLSS concentration (8,000–12,000 mg/L), reversible fouling rate of membrane increased with increasing F/M ratio because of the increased suspension viscosity caused by the increased activated sludge size or volume even in the same MLSS concentration.     

膜生物反应器(MBR)浸没式膜元件及组件

常见的浸没式膜元件及组件是由微滤和超滤膜制造的,这些膜是由高分子材料制成的,对污染物主要起截留分离作用。膜的材料要求耐受化学、微生物腐蚀,有机物、胶体、固体物质污堵,水压周期性变化,湍流冲击、气体抖动。膜元件外形尺寸具有多样性,不同品牌膜互换难度大。膜组件由若干个膜元件并联组成。建议在膜生物反应器的应用中在考虑膜元件及组件性能的同时加强生物处理工艺研究。     

超市废水的膜生物反应器中污泥特性之变化

在以处理超市废水实际工程的基础上,通过对污泥性质中的胞外聚合物（EPS）、溶解性微生物产物（SMP）、污泥粒径分布（PSD）变化的分析,得出污泥性质在接种膜生物反应器（MBR）后发生了明显的变化。对SMP的荧光分析发现,芳香族蛋白质类物质的量随着运行时间的增加有减小的趋势,而色氨酸类蛋白质类物质的量则相反。同时,发现EPS中荧光峰发生了显著的位移,说明了EPS性质发生了变化;通过对污泥的红外分析,发现污泥主要以糖类、蛋白质和脂肪族类物质为主,而随着时间的变化,污泥中的代表羟基基团的峰强度发生了明显的变化,说明污泥性质发生了变化;此外,通过PSD分析发现,污泥粒径中大粒径颗粒（大于100μm）是逐渐减小的,而小粒径颗粒（10μm）逐渐增多。     

二段淹没式膜生物反应器处理城市污水的研究

采用九保田板式膜,设计了二段淹没式膜生物反应器处理城市生活污水。运行结果显示,二段淹没式膜生物反应器能够增强高能级生物体蠕虫生长与少产污泥的目的。在污泥负荷为0.35~0.65g[COD]/(g[SS]·d)和容积负荷为2~5g[COD]/(L·d)的条件下,反应器出水COD和NH3-N的质量浓度分别为18.67mg/L和0.24mg/L,污泥产率为0.1kg[SS]/kg[COD]。     

MBR及其在难降解废水中的应用

膜生物反应器是将高效的膜分离技术与传统活性污泥法相结合的一种新型高效污水处理工艺。在膜生物反应器中,由平板膜及其构件组成的膜组件浸放于曝气池中,将曝气池中的细菌胶团和游离细菌全部保留在曝气池中,既能维持高浓度的活性污泥,污染物去除效率高,又能免去二沉池,保证出水悬浮物接近零的优良出水水质。重点阐述了膜生物反应器及膜生物反应器组件的分类及在难降解废水中的应用研究。     

一体式膜生物反应器（MBR）设备调试总结

文章主要介绍了一体式膜生物反应器（MBR）设备的调试运行。因设备中的关键部件——膜组件的存在与工艺的独特性——污泥不回流及微生物处于内源呼吸区；在调试过程孛为有效防止膜通量下降与达到出水水质标准；使得一体式膜生物反应器设备的调试与传统活性污泥处理工艺有所不同。     

膜生物反应器(MBR)处理废水的研究进展

文章综述了废水处理领域中的膜-生物反应器的基本特点、应用现状、存在问题以及国内外研究的进展,重点阐述了膜-生物反应器运行工艺、新型膜材料与器件,以及影响膜污染的因素与防治措施;并对今后的研究方向进行了展望。     

膜生物反应器工艺处理炼油废水中试研究

采用中空纤维膜生物反应器（MBR）工艺处理炼油废水,研究结果表明,MBR工艺可以有效的用于处理炼油废水,COD、氨氮和油去除率分别为92.9%、96.7%、84.7%,试验期间MBR出水COD平均为54.1mg/L,氨氮为1.85mg/L,油含量小于3.0mg/L。运行稳定后出水水质满足国家一级排放标准。     

The Effect of Pulsed Direct Current Field on the Membrane Flux of a New Style of Membrane Bioreactor

The effect of a pulsed direct current electric field on the membrane flux of an antifouling Membrane Bioreactor (MBR) designed and built in the laboratory was studied. The results showed that a pulsed direct current electric field had a significant effect on the membrane flux. The average membrane flux when using a pulse direct current electric field was between that of a steady electric field and that of no electric current under a trans‐membrane pressure drop of ΔP = 0.1 MPa and a pulsed direct current electric field strength of 20 V/cm. There was an optimum value of pulse intensity and pulse duration for the membrane flux. The shorter the pulse interval time was, the higher the frequency of power‐on, and the higher the average stable membrane flux of the MBR. This may have resulted from the fact that charged coarse particles and colloids account for 80 % of COD_cr and BOD₅ in urban domestic sewage. These particles and colloids moved away from the membrane surface at a certain electrical field strength, gradually thinning the particle sedimentary layer, reducing the membrane filtration resistance, and increasing the membrane flux significantly. However, the formation of a sedimentary layer on the membrane surface needed a significant amount of time and an appropriate pulse frequency while the MBR is powered on. This could save energy while keeping the membrane clean.     

Microbial Kinetics and Enzymatic Activities in Hybrid Moving‐Bed Biofilm Reactor‐Membrane Bioreactor Systems

A membrane bioreactor (MBR), a hybrid moving‐bed biofilm reactor‐membrane bioreactor (hybrid MBBR‐MBR_a) containing carriers in the anoxic and aerobic compartments, and a hybrid MBBR‐MBR_b containing carriers only in the aerobic zone were used in parallel and compared for treating municipal wastewater. The microbial kinetics and the evolution of the enzymatic activities of α‐glucosidase and acid and alkaline phosphatase as well as the bacterial diversity and bacterial community structure were studied to explain the removal of organic matter and nutrients. The MBR and the hybrid MBBR‐MBR_b showed the highest reduction percentages of chemical oxygen demand. Moreover, the hybrid MBBR‐MBR_b exhibited the highest removal performance of total nitrogen.     

A Bioelectrochemically‐Assisted Membrane Bioreactor for Simultaneous Wastewater Treatment and Energy Production

A bioelectrochemically‐assisted membrane bioreactor (BEAMBR), integrating a microbial fuel cell with a membrane bioreactor, was developed for energy recovery and efficient wastewater treatment. The stainless‐steel membrane module with biofilm, served not only as dynamic membrane separation device but also as biocathode. The effluent turbidity reached 0.8 NTU after stable operation, and particle with average size larger than 1.14 μm were effectively rejected from the mixed liquor by the dynamic membrane. The BEAMBR successfully removed the chemical oxygen demand and ammonium. With increasing hydraulic retention time and decreasing volumetric organic loading rate, the power production in this reactor was enhanced. The results showed that the BEAMBR is a promising process for efficient energy recovery and wastewater treatment.     

Microbial Fuel Cell Membrane Bioreactor in Wastewater Treatment,Electricity Generation and Fouling Mitigation

Membrane bioreactors (MBR) have gained much attention due to their ability to achieve higher treatment efficiency. However, high external energy consumption in aeration for membrane fouling mitigation has been limiting their application. Microbial fuel cells (MFC) can ideally extract energy from wastewater in the form of electricity and reduce membrane fouling. Thus, the use of MFC-MBR is rapidly expanding. However, the MFC-MBR design and operation is not fully mature and further research is needed to optimize the process efficiency and enhance the applicability. This review gives an overview of recent studies on the performances of MFC-MBR systems, regarding the design and configuration of the integrated system, irrespective of whether optimization was done or not in the operating system.     

硅橡胶膜生物反应器中乙醇发酵与渗透汽化的耦合

用硅橡胶膜生物反应器(SMBR)实验研究连续发酵-渗透汽化的耦合性能。发酵微生物采用酿酒干酵母,所用碳源为工业级葡萄糖。发酵过程由于产物抑制作用,在乙醇质量浓度达到73 g/L时趋于停滞,而耦合渗透汽化膜后,发酵罐内的乙醇质量浓度降低并维持在40 g/L,使发酵可以连续稳定地进行。在SMBR运行达到稳态后,乙醇的体积产率为4.02 g/(L.h)。发酵液中乙醇质量浓度维持在20~63 g/L,聚二甲基硅氧烷(PDMS)膜的总渗透通量为1 220~800 g/(m2.h),分离因子为5~9.2。与传统发酵和分离相同进料质量分数的乙醇溶液相比,乙醇发酵和渗透汽化在硅橡胶膜生物反应器中能相互耦合并得到强化。与较小规模耦合系统(发酵体积1 L和2 L)比较,性能稳定良好。     

乙醇发酵与渗透汽化在硅橡胶膜生物反应器中的耦合强化

用硅橡胶膜生物反应器(SMBR)实验研究了发酵-渗透汽化的耦合性能。发酵微生物采用酿酒活性干酵母,所用的碳源为工业级葡萄糖。间歇发酵过程由于产物抑制作用在乙醇浓度达到90g稬-1时就趋于停滞,而经耦合渗透汽化膜分离后,发酵罐内的乙醇浓度迅速降低并维持在40g稬-1,且发酵在此浓度下可以连续稳定地进行。 在SMBR运行达到稳态后,乙醇的体积产率为1.5gL-1h-1。SMBR中所用的聚二甲基硅氧烷(PDMS)复合膜由实验室自行制备,它能稳定分离含有酵母细胞的发酵液。当发酵液中乙醇浓度为92.7~49.5g稬-1时,PDMS复合膜的总通量为1490~1164g穖-2h-1,分离因子为6.9~7.8,与分离相同进料浓度的清洁模型溶液相比分别平均高出31%和14%。乙醇发酵和渗透汽化在硅橡胶膜生物反应器中能够相互耦合并得到强化。     

膜生物反应器中污泥膨胀对脱氮除磷的影响

膜生物反应器以其膜取代了常规活性污泥法中的二沉池的突出优点迅速成为污水处理的新的发展方向.试验研究了污泥膨胀时,膜生物反应器对脱氮除磷的影响.分别对比了在正常情况下和污泥膨胀时,膜生物反应器对CODCr、氨氮、TN、TP的去除率.试验结果表明:发生污泥膨胀后,对CODCr的去除率达到96.51%有所提高,对氨氮、TN、TP的去除率分别为75.9%、39.8%、19.7%均有不同程度的下降.     

丝状菌对膜生物反应器中溶解性有机物及膜污染的影响

该文以处理超市废水实际MBR工程为基础,通过对污泥膨胀过程中进出水、溶解性微生物产物(SMP)和胞外聚合物(EPS)中的溶解性有机物(DOM)特性的研究,发现SMP和进出水的DOM主要以蛋白质为主,且SMP较EPS含有更多大分子物质;同时发现SMP比EPS和进出水中含有更多50～100 kDa、100～500 kDa和...