不同预处理方式对超滤膜深度处理印染废水效能影响的研究

以印染废水处理站的二级出水为原水,考察了不同预处理方式(砂滤、微絮凝、微絮凝直接过滤)对超滤膜性能及其去除印染废水中污染物的影响。结果表明,砂滤随着运行时间的延长造成膜的不可逆污染,微絮凝可缓解膜污染,微絮凝直接过滤对膜污染在微絮凝基础上有所改善;不同预处理方式均能保证出水浊度小于0.1NTU;微絮凝直接过滤预处理工艺对CODCr去除率接近70%,微絮凝直接过滤处理方法能有效缓解膜污染,对浊度和有机物的去除效果较好,是较有优势的预处理工艺。     

絮凝-超滤组合工艺深度处理印染废水及阻力分析

采用絮凝-超滤组合工艺对工业印染废水的二级生化出水进行深度处理,探讨了絮凝、超滤及絮凝-超滤联用对废水中COD和浊度等去除的效果,从膜通量和膜阻力的角度分析了絮凝对减轻膜污染的作用.结果表明,超滤具有较好的除浊功能,去除率高达92%,COD去除率仅43%,PAC投加量为50mg·L~(-1)时,单独絮凝对浊度去除率可达60.5%,但对COD去除率低于20%.絮凝-超滤联用不仅能提高产水水质,使浊度和COD去除率分别达到99.8%和54%,而且对提高产水通量和减轻膜污染效果显著.通过阻力计算表明,直接超滤的阻力主要为可恢复阻力,不同压力下R_r/R_(ir)值均在0.7以上,絮凝+冲洗可大幅减小膜阻力,因而更适于工业化应用.     

混凝过滤-超滤-膜系统深度处理酒精废水试验研究

采用混凝过滤-超滤-膜系统对酒精废水的二级生化出水进行了深度处理,探讨了混凝过滤-超滤预处理对COD、浊度的去除效果,考察了反渗透膜的脱盐性能及不同清洗方式对反渗透膜通量恢复的影响。结果表明,混凝过滤-超滤预处理对废水COD和浊度去除效果显著,其对应去除率达到40%和99%以上;膜系统产水浊度、硬度、总铁质量浓度分别小于0.1 NTU、0.03 mmol/L和0.3 mg/L,电导率处于60～120μS/cm之间;混凝过滤出水和反渗透产水分别满足循环冷却水补充用水和锅炉补充水要求,混凝过滤配合消毒处理费用0.71元/m3,混凝过滤-超滤-膜系统处理总成本2.94元/m3,整套工艺具有较好的应用前景。     

PVDF超滤膜用于城市污水深度处理的试验研究

采用混凝沉淀-超滤组合工艺进行了城市二级出水深度处理的试验。结果表明,超滤膜对浊度、UV254、COD、PO43--P的平均去除率分别为100%、21.2%、28.36%、31.5%,超滤膜分离系统的产水率为84.6%。超滤前加混凝沉淀预处理,可以提高水中有机物的去除率,同时减轻了膜污染。     

曝气生物滤池-微絮凝过滤处理污染水源水的中试

采用曝气生物滤池(BAF)-微絮凝过滤工艺对受污染的河道水进行中试规模的试验研究,着重考察BAF和微絮凝过滤对污染物的综合处理效果.结果表明,当进水氨氮、COD、浊度和TP分别为15～25 mg/L、30～40 mg/L、7～15NTU和0.9～1.5 mg/L时,工艺对氨氮、COD、浊度和TP的去除率分别为89.0%、62.2%、90.1%和64.8%,出水远优于直接的混凝沉淀过滤工艺,可用于印染工业生产.     

微絮凝-超滤和混凝-沉淀-过滤处理微污染水库水对比试验

对微污染水库水采用微絮凝-超滤工艺和常规混凝-沉淀-过滤工艺进行对比试验。中试结果表明，微絮凝-超滤工艺出水水质稳定，对浊度、病原体微生物、有机物的去效果，都优于常规工艺。     

焚烧厂渗滤液厌氧出水组合工艺深度处理中试研究

采用"(改性预处理-管式超滤)+两级DT+树脂吸附"组合工艺深度处理垃圾焚烧发电厂渗滤液厌氧出水,中试实验结果表明:混凝沉淀-管式超滤单元运行稳定,且能有效去除污水中的悬浮物,降低浊度,对COD的去除率41.8%,对总硬的去除率28.1%;DTRO单元运行压力上涨平稳,污染物去除率高,其中COD、氨氮去除率分别达99.2%、99.2%;该组合工艺系统稳定可靠,出水COD 25 mg/L、氨氮1.6 mg/L,满足城镇污水处理厂污染物排放标准(GB18918-2002)中一级A标准,是一种可行的工艺。     

超滤集成工艺对西北村镇窖水处理的应用研究

研究了以超滤为核心,流程为颗粒活性炭-纳米金属簇-超滤-紫外线的集成净水工艺对原水中浊度、CODMn、氨氮的去除,进行了不同原水浊度下超滤的膜污染成因分析和化学清洗试验。结果表明,集成工艺出水浊度稳定在1 NTU以下,对CODMn和氨氮的平均去除率为29.86%和50.95%。出水水质达到了现行GB 5749-2006的要求。在短时间内较高浊度的进水对超滤膜不会造成不可逆的膜污染,但在持续较高浊度进水条件下膜阻力会快速提高并最终造成膜污染。对原水中的有机物和浊度进行更有效的预处理能减缓膜污染的进程,膜污染发生后进行有针对性的化学清洗能有效的恢复膜通量。     

大伙房汛期高浊污染二次絮凝超滤工艺研究

针对抚顺市突发强降雨导致大伙房水库原水浊度在短期之内迅速升高至982 NTU,水厂常规处理工艺难以应对高浊污染的情况,采用二次絮凝-超滤膜工艺代替原有过滤工艺作为水厂中远期工艺改造方案,对比进行了汛期过程中常规工艺和二次絮凝-超滤工艺对浊度、CODMn、细菌总数的去除效果实验。结果表明,采用二次絮凝-超滤工艺的出水水质能够满足GB5749-2006的要求,二次絮凝作为膜工艺的预处理可有效缓解膜污染,并且该工艺运行成本较低,可作为抚顺各水厂工艺改造备选方案。     

浸没式超滤膜组合工艺处理饮用水的中试研究

通过中试实验研究了混凝沉淀-超滤、混凝沉淀-砂滤-超滤和混凝沉淀-升流式曝气生物活性炭-超滤三种工艺处理饮用水的净水效果及对膜污染影响情况。结果表明,3种工艺的浊度和颗粒数去除率均能达到99%以上且不受原水水质影响,都能去除水中大多数的微生物和浮游动物,说明超滤膜组合工艺能有效的保证出水的生物安全性。超滤膜本身对水中溶解性有机物和氨氮的去除效果较差,相对于混凝沉淀-超滤工艺,选用混凝沉淀-砂滤-超滤工艺和混凝沉淀-升流式曝气生物活性炭-超滤工艺对COD_(Mn)、UV_(254)及氨氮的去除率分别提高了21.2%、18.2%、28.6%和40.8%、63.7%、59.2%,且这两种工艺的过滤阻力也远小于混凝沉淀-超滤工艺的过滤阻力。     

The Benefits of Ozone Treatment Prior to Flocculation Processes

The “microflocculation” effect of ozone in water treatment has received lately more interest, despite some lack of knowledge about the basic mechanisms and reactions. Practical studies at a direct filtration plant with preozonations show the advantages of ozone as coagulant at low dosages (1–2 mg/1) in improving filtrate quality and extending filter run times.     

低浊度废水的微絮凝变孔隙深层过滤

研究了微絮凝变孔隙深层过滤处理低浊度废水时,滤料粒径、絮凝剂种类、投加量、滤速等因素对过滤效果的影响。试验结果表明：由于变孔隙结构等原因,该系统具有用药量省、阻力损失小、出水量大及整床过滤效能好等优点。     

微絮凝纤维球过滤-超滤-纳滤组合工艺处理宾馆洗浴废水

以自主研制的涤纶高弹丝纤维球为滤料,提出了微絮凝纤维球过滤-超滤-纳滤组合工艺处理综合回用洗浴废水的方法.试验结果表明,超滤出水可以回用至宾馆厕所冲洗、绿化等环节,纳滤出水可以回用至宾馆洗衣和洗浴等水质要求较高环节,同时研究发现,膜组件经复合清洗剂清洗后,水通量恢复率可达到99%以上.     

Power Evaluation of the Los Angeles Oxygen–Fed Ozone System

The Los Angeles Department of Water and Power (LADWP) operates a 600 mgd (2,270 ML/day) direct filtration water treatment plant which includes a 7,900 lb/day (149 kg/hr) ozonation system. Ozone is applied as a preoxidant for the purposes of disinfection and microflocculation. The ozonation system is unique in that high purity oxygen is generated on–site and is used as the feed–gas in a once–through system. The process was selected through competitive bids and evaluated for total present worth from 20–year life cycle costs which included capital plus energy expenses. Power consumption (and penalty) was valued at $6,500/kW. System power demand was measured at nine ozone production rates. A minimum specific energy of 6.5 kWh/lb (14.3 kWh/kg) of ozone was observed when generating ozone at a concentration between 5 and 6 % (wt) [65 and 80 g/m³; where the standard temperature and pressure are 70F (21.11 C) and 1 atm, respectively]. The test methodology and data assessment considerations were developed jointly by the owner and manufacturer, and produced results with practical significance beyond the performance testing objective.     

Rheological behavior of blends of natural rubber and styrene–butadiene rubber latices

The rheological behavior of blends of natural rubber (NR) and styrene–butadiene rubber (SBR) latices has been studied with reference to the effects of blend ratio, shear rate, surface-active agents (casein and sodium carboxymethyl cellulose), and temperature. When the SBR content was less than 50%, the viscosities of the blends appeared to be a nonadditive function of the viscosities of the constituent homopolymers; i.e., a positive deviation was observed. This was due to the structural buildup of the SBR domains. The SBR domains underwent agglomeration and consequently so-called microflocculation took place. The viscosities of all the blends were found to decrease with increase of temperature and shear rate. The increase in temperature and shear rate marginally weakened the structural buildup as evidenced by the lowering of viscosity. As the SBR content in the system increased, the pseudoplasticity of the blend increased. Even in the presence of surface-active agents the blends showed composition-dependent positive deviation. However, surface-active agents marginally reduced the extent of structural buildup by reducing the microflocculation behavior of SBR domains. © 1995 John Wiley & Sons, Inc.     

双金属催化滤料生物滤池处理效果及对膜污染影响研究

双金属催化滤料生物滤池替代传统生物滤池,作为超滤膜系统的预处理工艺,可提高三氮的去除效率,保证产水水质稳定,显著减缓超滤膜污染,延长膜使用寿命。生物催化滤池内催化还原反应促进反硝化系统的进行,保证了水中硝酸氮和亚硝酸氮的分解去除;研究表明,生物催化滤池预处理较常规生物滤池可将TOC的去除率由73.2%提高到81.5%,其增加部分的主要成分为可引起膜污染的芳香蛋白类和富里酸类有机污染物。此外,双金属催化滤料增加了滤池的过滤精度,其出水胶体平均粒径明显小于常规生物滤池。催化还原反应产生的铁离子在过滤紊流的环境中微絮凝,进一步去除了微污染水源水中的胶体和悬浮物,减轻了胶体颗粒对超滤膜的污染。除具有常规滤池的生物降解、过滤作用外,双金属催化滤料生物滤池还具有催化还原和微絮凝的协同作用,显著提高了水中有机污染物和胶体颗粒的去除率,超滤膜污染得到有效减缓。     

纤维束滤料直接过滤废水的试验研究

论述了纤维束滤料直接过滤城市二级生化处理出水的试验情况。结果表明，纤维束过滤运行稳定，出水水质好，滤阻小，过滤周期长。     

水投加硫酸铝和三氯化铁后的过滤特性探讨

通过试验研究探讨了上向流聚苯乙烯滤料直接过滤原水时硫酸铝和三氯化铁的过滤特点，试验结果表明：对浊度为20NTU的原水，在硫酸铝和三氯化铁的投加量均为5mg／L时，三氯化铁过滤时出水浊度较低，但它引起的水头损失增长较快。试验结果还表明：上向流聚苯乙烯滤料直接过滤时，阳离子型聚合物T3010的投加量对过滤周期、出水水质、水头损失都有着非常重要的影响。     

Operating Strategy To Meet SWTR Disinfection Regulations At The Los Angeles Aqueduct Filtration Plant

Preozonation facilities were installed at the Los Angeles Aqueduct Filtration Plant originally to enhance coagulation assistance (microflocculation). The Surface Water Treatment Rule will amend this primary purpose to meeting disinfection standards. Additional ozone generation equipment and a revised ozone system operating strategy will be required to accomplish these changed objectives. The topics discussed in this paper are the considerations surrounding the development of a successful, cost-effective operating strategy. The strategy proposed herein was based on data collected between January and July 1991. On-line process monitoring plans and automated system control logic are described.