EOW—MBR组合工艺处理偏二甲肼废水

利用EOW-MBR组合工艺处理偏二甲肼废水,并与MBR工艺的单独处理效果进行对比。结果表明:EOW-MBR组合工艺对偏二甲肼废水有良好的处理效果,在原水COD_(Cr)为800～1000 mg/L,偏二甲肼为300 mg/L的条件下,组合工艺出水COD_(Cr)为55 mg/L,偏二甲肼为0.3～1.5 mg/L,COD_(Cr)处理结果优于《航天推进剂水污染物排放标准》(GB 14374-93)要求,偏二甲肼处理结果接近GB 14374-93要求。而采用MBR工艺单独处理时,出水COD_(Cr)在90 mg/L左右,偏二甲肼在45 mg/L左右。处理结果与组合工艺相比较差,尤其是偏二甲肼远远超过GB 14374-93排放要求。     

Sub-critical fouling in a membrane bioreactor for municipal wastewater treatment: experimental investigation and mathematical modelling

Fouling is a major limitation for the application of membrane bioreactors (MBRs) in municipal wastewater treatment; the critical flux concept represents a valid tool for process optimisation in planning fouling control strategies. The paper presents the results obtained on a large pilot MBR equipped with a plate-and-frame ultrafiltration membrane. The experimental assessment of flux criticality was carried out by flux-stepping tests showing the positive impact of liquid temperature on the value of the critical threshold. The reliability of short-term tests was then verified over a long period by determining the time of sustainability, t(sust), of six different sub-critical fluxes ranging between 17 and 30Lm(-2)h(-1). An exponential fitting was observed in terms of fouling rate both before and after t(sust), though fouling after t(sust) is likely to be ascribed not only to cake formation. Finally, a new mathematical formulation was proposed according to the local flux approach to model the sub-critical TMP transients. The model involves both bound and free forms of EPS and, once experimentally calibrated, it provided a fair prediction of the TMP jump.     

MBR膜在NAVECO发动机分公司污水改造工程中的应用

通过在好氧池加膜生物反应器来取消二沉池,解决了传统活性污泥法占地面积大的问题。结果表明:膜生物反应器易于一体化实现自动控制,操作管理方便并能够保证出水水质稳定可靠,在NAVECO发动机分公司实际应用中取得了良好的效果。     

AO/MBR/臭氧氧化工艺处理制衣废水

对天津某制衣厂废水处理系统存在的水量和水质等问题进行调研分析,在充分利用原有处理构筑物和设备,同时利用厂区周围空地的前提下,采用AO/MBR/臭氧催化氧化工艺进行扩容和升级。工程运行结果表明,改造工艺经调试运行稳定,处理出水BOD5、SS、色度等达到《城市污水再生利用城市杂用水水质》(GB/T18920-2002)标准。     

Characterisation of hydrodynamics induced by air injection related to membrane fouling behaviour

The study focuses on fine bubble and spherical cap bubble injection in case of outside/in fibres immersed in a tank. The objectives are to quantify liquid circulations and shear stresses along the membrane and to understand their effects on the fouling resistance. Thus, both filtration experiments and hydrodynamic characterisation were performed in the same aeration conditions. Only particle cake deposit was studied as fouling mode and the hydrodynamics was characterized experimentally by 2-phase flow particle image velocimetry (PIV) and numerically with the CFD code FLUENT. Results presented in this paper are limited to tight hollow-fibres to well understand hydrodynamics without fibre motion. One important result is that mean values of wall shear stress are very low (maximum 0.25 Pa) eliminating the wall shear stress as a mechanism able to explain filtration performances for a non-confined aeration without fibre displacement. In addition, an analysis has been conducted in terms of horizontal liquid flow toward the membrane. The quantification of this flow allowed to conclude that i) for a given local bubble flow rate, there is no influence of the kind of aeration on this horizontal flow rate; and ii) the filtration performances can be correlated with this horizontal flow. The reason might be an over concentration of particles near the membrane surface induced by this flow.     

电镀工业园区污水处理部分工艺的选型

依据电镀集中园区废水的特点采取有针对性的分类收集,采用化学法＋膜生物（MBR）＋RO膜脱盐处理工艺达标排放和回用,对比了部分常见工艺的特点,包括中水回用系统的设计注意事项,强调电镀污水源头分流的意义。     

Engineering design approaches for minimum fouling in submerged MBR

A contributor to success in managing membrane operations is to be able to identify suitable engineering design approaches to slow down the membrane fouling rate. Two such approaches were discussed in this study, namely: (1) offsite chemical and mechanical cleaning, and (2) air scouring. A longer subsequent operation time was observed after a membrane was cleaned chemically compared with mechanically. For air scouring during membrane operation, the investigation aimed at determining the crossflow velocity induced by coarse and fine bubble diffusers. Higher crossflow velocities were obtained with the latter. Uniformly distributed fine air bubbling might possibly have caused less uplift resistance and induced higher crossflow velocities. Such air scouring, at critical aeration intensity, was able to prolong the membrane operation for up to 8 months without needing chemical or mechanical cleaning.     

污水处理中膜生物反应器的应用研究

膜生物反应器（MBR）是通过膜强化生化反应的污水处理新技术,具有污染物去除效果好,污泥产率低的优点.本文主要对现有的MBR形式和特点进行了归纳,对其应用中存在的问题进行了分析并提出了改进措施,并通过具体试验对其应用情况予以说明.     

计算流体力学对膜生物反应器水力学特征的模拟研究

通过计算流体力学(CFD)中的FLUENT软件,对膜生物反应器内流场和流态进行模拟,定量给出了其流速与剪切力的分布.研究了膜组件距离反应器底部不同距离时的水力学情况和水力学条件.对比了膜生物反应器中,玻璃纤维编织管式膜组件与平板膜组件,由于构型不同所导致的水力学条件差异.结果表明,从雷诺数和质量流速率参数分析,玻璃纤维编织管式膜组件的水力学条件更好,更有利于膜污染的防治.探讨了单个与多个曝气器情况下的流速分布,结果表明,后者流速分布更为均匀.由本文研究结果可知,计算流体力学可以作为一个有力的工具应用于MBR及其膜污染控制研究中.     

北京市北小河再生水厂MBR工艺介绍

北小河再生水厂是在原北小河污水处理厂基础上改扩建而成的,采用膜生物反应器( MBR)工艺,处理规模为6万m3/d,是目前国内市政污水处理中最大规模的MBR工程.工程于2008年4月试运行,7月正式运行,水厂运行稳定,出水水质优良,出水满足《城市污水再生利用城市杂用水水质》(GB/T18920-2002)中“车辆冲洗”水...