膜生物反应器中膜污染机理与应对

膜生物反应器是将膜分离技术和生物反应器结合而成的一种新型污水处理工艺,文章主要针对膜生物反应器中膜污染进行了综述,分析了膜污染途径,并提出了应对措施。     

膜生物反应器最佳组合工艺及其污水处理特性研究

为选择膜生物反应器的最佳组合工艺,采用实际生活污水研究了不同生物反应器型式对膜分离及其污水处理特性的影响,并对其操作条件进行了初步研究。结果表明:     

MBR在污水处理中的应用与研究进展

膜生物反应器(MBR)是近年来受到广泛关注的污水处理与回用领域的新技术之一.综述了膜生物反应器水处理技术在国内外的应用及研究进展,分析了膜组件性能、混合液特性与操作参数等方面对膜污染形成的影响,指出了预防和控制膜污染的措施,其中包括膜组件自身优化设计、改善工艺运行条件及其膜污染的清洗,最后展望了膜生物反应器技术的前景.     

膜组器结构优化及工艺运行参数调整研究

膜生物反应器技术是当前最先进的污水处理技术之一,在世界范围内广泛应用于市政污水处理领域。该技术有着出水水质好、占地小、污泥排放量少、运行稳定、操作简单等优点。但是一次性投资及运行费用较高等问题阻碍了其在污水处理中的推广应用。传统连续曝气控制膜污染是膜生物反应器最大耗能部分,约占整个系统能耗的60%左右。为有效降低膜生物反应器工艺的运行费用,同时保证曝气控制膜污染的效果,笔者从膜片间距,结合曝气方式、气水比3方面进行研究,以优化膜组器结构实现膜生物反应器工艺运行费用的根本性降低。经研究发现当膜片间距为24 mm,气水比为30:1,曝气方式为曝气10 s停10 s的频率时,曝气控制膜污染的效果与连续曝气控制膜污染效果相似,甚至更好。以此研究为基础,确定了针对北京市郊区县农村排放污水的膜生物反应器工艺的运行参数:污泥浓度为(5～12)g/L;气水比为(20～40)∶1;每(2～3)个月进行1次在线清洗,清洗药剂浓度为3 g/L;自吸泵抽停比为7∶1。     

膜生物反应器(MBR)在农村污水处理中的应用

<正>膜生物反应器(MBR)是将生物处理与膜分离技术相结合而形成的一种高效污水处理新工艺。膜的孔径只有0.1～0.4微米,具有高效的截流作用和分离作用,将微生物完全截流在反应器内,使废水中的污染物高效降解和高效分离,得到优质的出水。MBR技术彻底变革了传统的水处理工艺,实现了同步解决水污染和水资     

膜生物反应器的技术经济分析

膜生物反应器 (MBR)是通过膜分离技术强化污水生物处理的新技术。综述了该技术在我国的应用现状 ;并对MBR进行初步的技术经济分析。研究结果表明 :影响膜生物反应器运行费用的关键因素为膜通量和使用寿命     

膜-生物反应处理工艺中微生物对系统的影响

膜-生物反应器是近年来污水处理研究的热点,但受膜污染因素的影响,使其在实际应用中发展缓慢.由于膜-生物反应器的运行机理不是在生物反应器和膜组件的基础上简单叠加,并且由于生物特性和种类的改变,因此对系统的影响也不同于传统的活性污泥法.由于其独特的运行方式使微生物种类、数量发生变化,微生物在膜-生物反应器中不仅仅只起到去除...     

膜生物反应器工艺处理生活污水中试研究

膜生物反应器是将污水的生物处理和活性污泥的过滤分离结合在一起的一种新型的污水处理工艺。本研究中对膜生物反应器工艺处理城市生活污水进行了中试研究,研究的内容包括:(1)对膜生物反应器工艺     

膜—生物反应处理工艺中微生物对系统的影响

膜—生物反应器是近年来污水处理研究的热点,但受膜污染因素的影响,使其在实际应用中发展缓慢。由于膜—生物反应器的运行机理不是在生物反应器和膜组件的基础上简单叠加,并且由于生物特性和种类的改变,因此对系统的影响也不同于传统的活性污泥法。由于其独特的运行方式使微生物种类、数量发生变化,微生物在膜—生物反应器中不仅仅只起到去除有机物和脱氮、除磷的作用,对系统的运行也产生了一定的影响,尤其是对膜污染的影响。该文从微生物角度对其进行阐述,以期为膜污染治理提供一份参考。     

三种型式膜-生物反应器工艺运行特性研究

研究了三种不同型式的生物反应器即活性污泥反应器（ＡＳＲ）、生物膜反应器（ＢＲ）和复合式反应器（ＨＲ）分别与膜分离相组合时的运行特性。结果表明不同膜－生物反应器组合工艺之间，污染物去除效率相差不大，但膜通透量却存在明显差异。膜－复合式反应器组合工艺的产水率最高。膜面污染物及其影响因素分析表明，膜面污染物主要为固体污泥和溶解性有机物，分别与生物反应器混合液中悬浮污泥浓度和上清液有机物浓度相关。膜－复合式生物反应器膜面沉积的污泥量和吸附的有机物量均居中。因而膜通透量最大。     

Characteristics of membrane fouling in submerged membrane bioreactor under sub-critical flux operation.

Recently, the membrane bioreactor (MBR) process has become one of the novel technologies to enhance the performance of biological treatment of wastewater. Membrane bioreactor process uses the membrane unit to replace a sediment tank, and this can greatly enhance treatment performance. However, membrane fouling in MBR restricts its widespread application because it leads to permeate flux decline, making more frequent membrane cleaning and replacement necessary, which then increases operating and maintenance costs. This study investigated the sludge characteristics in membrane fouling under sub-critical flux operation and also assessed the effect of shear stress on membrane fouling. Membrane fouling was slow under sub-critical flux operation. However, as filamentous microbes became dominant in the reactor, membrane fouling increased dramatically due to the increased viscosity and polysaccharides. A close link was found between membrane fouling and the amount of polysaccharides in soluble EPS. The predominant resistance was the cake resistance which could be minimized by increasing the shear stress. However, the resistance of colloids and solutes was not apparently reduced by increasing shear stress. Therefore, smaller particles such as macromolecules (e.g. polysaccharides) may play an important role in membrane fouling under sub-critical flux operation.     

一体式膜生物反应器膜污染防治理论研究

从理论上分析了一体式膜生物反应器内曝气量与污水流量、反应器设计高度、主副腔过流面积的关系,膜外污染错流临界流速与抽吸压力及主腔宽度的关系,膜管内污染的临界速度与膜管径、膜壁吸力的关系,并得出采用化学方法消除膜污染的原理。     

Fouling with aerobic granule membrane bioreactor

Aerobic granulation (AG) and membrane bioreactor (MBR) are two promising, novel environmental biotechnological processes that draw interest of researchers working in the area of biological wastewater treatment. Membrane fouling in the combined aerobic granular membrane bioreactor (AGMBR) process and the conventional MBR process was investigated in this work. The irreversible fouling on hollow-fibre membranes in both reactors were observed with the multiple staining and confocal laser scanning microscope technique. Following physical and chemical washing, the external fouling layers were mostly removed. However, the biofilms built up in the interior surface of membrane remained and contributed to the irreversible fouling resistance. AGMBR retained most cells with granules, thereby reducing their penetration through membrane and thus the chance to form internal fouling layer. The internal biofilm layer was principally composed of live cells embedded in a matrix of proteins and polysaccharides, with that on AGMBR denser and thicker than that on MBR. Prevention of development of internal biofilm is essential to reduce irreversible fouling of AGMBR and MBR membranes.     

Effect of membrane characteristics on the performance of membrane bioreactors for oily wastewater treatment

Influence of membrane material and pore size on the performance of a submerged membrane bioreactor (sMBR) for oily wastewater treatment was investigated. The sMBR had a working volume of about 19 L with flat sheet modules at the same hydrodynamic conditions. Five types of micro- and ultra-polymeric membranes containing cellulose acetate (CA), cellulose nitrate (CN), polyamide (PA), polyvinylidene difluoride (PVDF) and polyethersulfone (PES) were used and their filtration performance in terms of permeability, permeate quality and fouling intensity were evaluated. Characterization of the membranes was done by performing some analysis such as pore size distribution; contact angle and scanning electronic microscopy (SEM) microphotograph on all membranes. The quality of permeates from each membrane was identified by measuring chemical oxygen demand (COD). The results showed more irreversible fouling intensity for membranes with larger pore size which can be due to more permeation of bioparticles and colloids inside the pores. Membrane characteristics have a major role in the preliminary time of the filtration before cake layer formation so that the PA with the highest hydrophilicity had the lowest permeability decline by fouling in this period. Also, the PVDF and PES membranes had better performance according to better permeate quality in the preliminary time of the filtration related to smaller pore size and also their better fouling resistance and chemical stability properties. However, all membranes resulted in the same permeability and permeate quality after cake layer formation. An overall efficiency of about 95% in COD removal was obtained for oily wastewater treatment by the membranes used in this study.     

Hybrid membrane bioreactor for water recycling and phosphorus recovery.

This paper deals with the performance of hybrid membrane bioreactor (MBR) combining the precoagulation/sedimentation and membrane bioreactor. The hybrid MBR not only produces the treated water with excellent permeate quality but also shows much lower membrane fouling than the conventional MBR. It may come from its extremely low F/M ratio to maintain the low viscosity even in the high MLSS concentration range of about 20,000 mg/L. Some results of microbial community analysis in MBRs was conducted to demonstrate the other reason for its lower membrane fouling. Hybrid MBR has a high potential to be used for the recycling use of the municipal wastewater. Coagulated sludge produced in the hybrid MBR is a promising phosphorus resource. This paper also contains a recent progress of phosphorus recovery technology, which uses a new phosphoric acids absorbent, i.e. the hexagonal mesostructured zirconium sulfate (ZS). The ZS has the extremely high adsorption capacity of phosphoric acids through anion exchange. The adsorbed phosphoric acids are released from the ZS in a high pH range of about 13.     

膜生物反应器的实验研究及在水处理中的应用

膜生物反应器的实质是由膜组件和生物反应器两部分组成，通过强化生化反应的水处理新技术，本介绍了膜生物反应器(MBR)的水处理机理、特点、应用类型、存在的问题，以及膜生物反应器在水处理中的应用情况。     

Optimal performance of an immersed membrane bioreactor equipped with a draft tube for domestic wastewater reclamation.

One of the options to prevent membrane fouling is to implement air lifting that can improve the cake removal from the membrane surface. This study presents the results of tests that were carried out at the Institutes for Desert Research, Kiryat Sde-Boker, Israel, and focused on the influence of hydrodynamic conditions on fouling in a pilot-scale immersed membrane bioreactor (IMBR) using a hollow fiber membrane module of ZW-10 (Zenon Environmental, Canada) under ambient conditions. In this system, the cross-flow velocities across the membrane surface were induced by one conical and four cylindrical draft-tubes. The relationship between the crossflow velocity and the aeration intensity, the influence of the crossflow on fouling rate under various hydrodynamic conditions were investigated and optimal operating conditions were obtained. Optimal operating conditions were reached during the long-term experiment period (70 days) for the treatment of domestic wastewater. The system was stable without external chemical cleaning. The results showed that the permeate was of high quality, and the removal of COD and BOD was 94.0% and 98.8%, respectively.The crossflow near the membrane surface reveals a major contribution for minimizing membrane fouling, and could offer guidelines for future design of similar systems.     

Removal of cyanide from acrylonitrile wastewater using gas membrane

Acrylonitrile wastewater is one of the most refractory industrial wastewaters as it contains cyanide at a high concentration. This study introduced a safe, effective and economic strategy, that is, use of the gas membrane to acrylonitrile wastewater treatment. Due to the complicated constituents of acrylonitrile wastewater, cyanide removal rate by gas membrane is very low. In order to enhance HCN removal, the operational conditions were optimized; pre-treatment strategies for fouling mitigation were also proposed and tested for acrylonitrile wastewater. The optimal operational parameters were achieved at an acidified pH of 5.0, wastewater velocity of 0.14 m s(-1), NaOH concentration of 10% and a temperature of 40 °C. The major factor affecting HCN removal was the pH of the acidified wastewater. The reason for the low removal rate was further explored and found to be the decrease of HCN transfer coefficient, which was caused by membrane fouling. Furthermore, the predominant foulants have been identified as colloidal organic materials and inorganic salts. Alkalization, which is effective in reducing these materials, has been proven to be most effective in mitigating membrane fouling and improving HCN removal, which was also confirmed by a pilot-scale study. The overall removal rate was therefore significantly enhanced to 87.1%.     

Bio-layer management in anaerobic membrane bioreactors for wastewater treatment.

Membrane separation technology represents an alternative way to achieve biomass retention in anaerobic bioreactors for wastewater treatment. Due to high biomass concentrations of anaerobic reactors, cake formation is likely to represent a major cause of flux decline. In the presented research, experiments are performed on the effect of biomass concentration and level of gas sparging on the hydraulic capacity of a submerged anaerobic membrane bioreactor. Both parameters significantly affected the hydraulic capacity, with biomass exerting the most pronounced effect. After 50 days of continuous operation the critical flux remained virtually unchanged, despite an increase in membrane resistance, suggesting that biomass characteristics and hydraulic conditions determine the bio-layer formation rather than the membrane's fouling level. The concept of bio-layer management is introduced to describe the programmed combination of actions performed in order to control the formation of biomass layer over membranes.     

一体式膜生物反应器处理焦化废水

介绍了用一体式膜生物反应器(M BR)处理焦化废水的技术,讨论了对焦化废水中的COD,NH3-N和浊度的去除效果及影响因素。实验结果表明,一体式膜生物反应器用于处理焦化废水在技术上是可行的,调整合适的操作参数,其对焦化废水中的COD,NH3-N和浊度的平均去除率分别达到80%、95%、90%以上,操作简单,出水水质好,稳定,且优于国家一级排放标准,有一定的推广意义。