给水管壁生物膜附着异养菌与水中悬浮菌活性比较

使用生物膜培养反应器（RAB），在实验室的可控条件下，待挂片上的生物膜达到稳定后进行间歇运行，分别对生物膜中异养菌及水中悬浮菌的活性进行了研究。结果发现，在间歇运行模式下，AOC浓度随着运行时间的延长而不断下降，经过了24h后由最初的64μg／L下降到28μg／L（以乙酸碳计）。水中的悬浮菌和生物膜中异养菌的数量均随着运行时间先增加后下降，但前者波动较大。在前12h，悬浮菌和生物膜上附着细菌的活性都有所增加，之后悬浮菌的活性迅速降低，而生物膜上附着细菌的活性仅有小幅度下降，表明其对环境的适应能力要强于水中的悬浮菌。     

动态膜生物反应器处理公路服务区污水

动态膜生物反应器(DMBR)结合了传统生物处理和膜过滤的优点,能处理高浓度污水。介绍了某公路服务区污水采用动态膜生物反应器处理系统工程的工艺特点、建设情况、技术经济指标及设计经验等。该工程的运行实践表明,动态膜生物反应器适用于公路服务区污水处理。     

自生动态膜生物反应器处理城市污水的中试研究

分别利用筛绢和钢丝网作为自生动态膜生物反应器的基材并进行了处理城市污水的中试研究.结果表明,钢丝网组件和筛绢组件的出水水质相差不大,出水COD分别为57.5 mg/L和50.4 mg/L,NH 4-N分别为1.39 mg/L和2.84 mg/L;在运行了25 min后出水浊度可降至5NTU以下并保持稳定;出水SS接近于零.钢丝网组件的平均通量为30.3 L/(m2·h),筛绢组件的平均通量为51.9 L/(m2·h),后者比前者高71%,但钢丝网的强度明显高于筛绢.     

重力出流式MBR处理生活污水及毛纺废水

针对膜生物反应器(MBR)能耗高的问题，开发了一种利用生物反应区内液位水头的重力出流式MBR。采用该反应器处理生活污水和毛纺废水，处理出水水质达到了《城市污水再生利用——城市杂用水水质》(GB／T 18920-2002)标准。试验结果表明：选择合适的曝气量不仅有助于提高膜通量、有利于控制膜污染，还有利于生物反应器中氧的传递。MBR系统中污泥浓度为12g／L、表观气速从O．028m／s上升到O．085m／s时，混合液中与清水中氧总转移系数的比值基本维持在O．27～O．29的水平。     

新型膜生物反应器的设计及其性能研究

结合无泡曝气原理和气体反冲洗方法,设计了一种新型的一体式膜生物反应器(MBR),并将其与传统MBR进行了对比.结果表明,当处理黄麻生物脱胶废水时,在相同的运行条件下,新型MBR中混合液的DO含量明显高于传统MBR,对COD的去除效果也明显好于传统MBR;另外,与传统MBR相比,新型MBR具有膜过滤压力小、膜污染轻、能耗低等优点.     

Kinetics of nitrate and perchlorate removal and biofilm stratification in an ion exchange membrane bioreactor

The biological degradation of nitrate and perchlorate was investigated in an ion exchange membrane bioreactor (IEMB) using a mixed anoxic microbial culture and ethanol as the carbon source. In this process, a membrane-supported biofilm reduces nitrate and perchlorate delivered through an anion exchange membrane from a polluted water stream, containing 60 mg/L of NO₃⁻ and 100 μg/L of ClO₄⁻. Under ammonia limiting conditions, the perchlorate reduction rate decreased by 10%, whereas the nitrate reduction rate was unaffected. Though nitrate and perchlorate accumulated in the bioreactor, their concentrations in the treated water (2.8 ± 0.5 mg/L of NO₃⁻ and 7.0 ± 0.8 μg/L of ClO₄⁻, respectively) were always below the drinking water regulatory levels, due to Donnan dialysis control of the ionic transport in the system.Kinetic parameters determined for the mixed microbial culture in suspension showed that the nitrate reduction rate was 35 times higher than the maximum perchlorate reduction rate. It was found that perchlorate reduction was inhibited by nitrate, since after nitrate depletion perchlorate reduction rate increased by 77%. The biofilm developed in the IEMB was cryosectioned and the microbial population was analyzed by fluorescence in situ hybridization (FISH). The results obtained seem to indicate that the kinetic advantage of nitrate reduction favored accumulation of denitrifiers near the membrane, whereas per(chlorate) reducing bacteria were mainly positioned at the biofilm outer surface, contacting the biomedium. As a consequence of the biofilm stratification, the reduction of perchlorate and nitrate occur sequentially in space allowing for the removal of both ions in the IEMB.     

好氧MBR与序批式MBR处理生活污水的比较

比较了中试规模的好氧式膜生物反应器及序批式膜生物反应器处理生活污水的效果。结果表明，两者对COD及氨氮的去除效果相当，且都具有良好的抗冲击负荷能力；在总氮去除上，序批式膜生物反应器优于好氧式膜生物反应器；在稳定运行阶段，当好氧式膜生物反应器及序批式膜生物反应器处理同等水量时，过膜阻力增加率分别为1．68和1．03kPa／m。通过测定膜丝上多糖的含量分析了两者在膜污染速率上存在差异的原因，发现序批式膜生物反应器膜丝上的多糖含量要少于好氧式膜生物反应器。     

不同中水回用模式的技术经济分析

根据国内外中水回用的工程实践，总结了目前城市中水回用的典型处理工艺、回用途径，提出了城市中水回用的7种模式，从技术经济角度分别对这几种模式进行了分析，提出了适合我国国情的城市中水回用模式，展望了我国中水回用的发展趋势。     

Membrane bioreactor for the drinking water treatment of polluted surface water supplies

A laboratory membrane bioreactor (MBR) using a submerged polyethylene hollow-fibre membrane module with a pore size of 0.4 microm and a total surface area of 0.2 m2 was used for treating a raw water supply slightly polluted by domestic sewage. The feeding influent had a total organic carbon (TOC) level of 3-5 mg/L and an ammonia nitrogen (NH(3)-N) concentration of 3-4 mg/L. The MBR ran continuously for more than 500 days, with a hydraulic retention time (HRT) as short as 1h or less. Sufficient organic degradation and complete nitrification were achieved in the MBR effluent, which normally had a TOC of less than 2 mg/L and a NH(3)-N of lower than 0.2 mg/L. The process was also highly effective for eliminating conventional water impurities, as demonstrated by decreases in turbidity from 4.50+/-1.11 to 0.08+/-0.03 NTU, in total coliforms from 10(5)/mL to less than 5/mL and in UV(254) absorbance from 0.098+/-0.019 to 0.036+/-0.007 cm(-1). With the MBR treatment, the 3-day trihalomethane formation potential (THMFP) was significantly reduced from 239.5+/-43.8 to 60.4+/-23.1 microg/L. The initial chlorine demand for disinfection decreased from 22.3+/-5.1 to 0.5+/-0. 1mg/L. The biostability of the effluent improved considerably as the assimilable organic carbon (AOC) decreased from 134.5+/-52.7 to 25.3+/-19.9 microg/L. All of these water quality parameters show the superior quality of the MBR-treated water, which was comparable to or even better than the local tap water. Molecular size distribution analysis and the hydrophobic characterisation of the MBR effluent, in comparison to the filtered liquor from the bioreactor, suggest that the MBR had an enhanced filtration mechanism. A sludge layer on the membrane surface could have functioned as an additional barrier to the passage of typical THM precursors, such as large organic molecules and hydrophobic compounds. These results indicate that the MBR with a short HRT could be developed as an effective biological water treatment process to address the urgent need of many developing countries that are plagued by the serious contamination of surface water resources.     

Recent advances in membrane bioreactors (MBRs): Membrane fouling and membrane material

Membrane bioreactors (MBRs) have been actively employed for municipal and industrial wastewater treatments. So far, membrane fouling and the high cost of membranes are main obstacles for wider application of MBRs. Over the past few years, considerable investigations have been performed to understand MBR fouling in detail and to develop high-flux or low-cost membranes. This review attempted to address the recent and current developments in MBRs on the basis of reported literature in order to provide more detailed information about MBRs. In this paper, the fouling behaviour, fouling factors and fouling control strategies were discussed. Recent developments in membrane materials including low-cost filters, membrane modification and dynamic membranes were also reviewed. Lastly, the future trends in membrane fouling research and membrane material development in the coming years were addressed.