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1.
广州地区设置的管道直饮水项目较多,调查显示,广州地区的小区直饮水新建项目处理工艺逐步由反渗透向纳滤膜技术过渡。以广州金山谷项目小区直饮水系统设计为例,介绍其直饮水系统的处理工艺流程、纳滤膜设备、管网设计及管材的选用,并对项目进行了相应的经济分析。  相似文献   

2.
该文针对珠江广州河段水体污染严重,直接威胁到广州市供水安全的情况,提出除了开发新水源及工程调水解决水源水质问题外,还可从净水处理的角度出发,通过改良净水工艺——在传统的常规处理工艺中增加生物预处理及纳滤膜(NF)处理,从而从另一方面有效保障广州市的供水安全。  相似文献   

3.
针对当前饮用水水源的污染特征,提出了以纳滤为核心的饮用水深度处理工艺,分析了纳滤膜的截留和扩散机理,探讨了纳滤膜对水中有机物及矿物质的分离效果及影响因素,构建并评价了以纳滤膜为核心的饮用水深度处理工艺系统,为饮用水深度处理开辟了新的途径。  相似文献   

4.
文章以锡林浩特市巴彦宝力格水源地供水工程为例,将纳滤膜系统设计应用在地下水软化和除氟处理工艺中,根据原水水质化验结果选择相应型号膜元件,同时对纳滤膜系统进行优化设计,根据工程投资估算和经济评价对该系统产水水价进行了测算。  相似文献   

5.
纳滤膜技术及其应用的研究进展   总被引:6,自引:0,他引:6  
随着膜技术的发展,20世纪80年代出现的纳滤膜弥补了反渗透与超滤之间的空白。纳滤膜(nanofiltration membrane,NF)又称“疏松型”反渗透膜。通常情况下,膜的截留相对分子质量界限为200~1 000。与截留相对分子质量相对应的膜孔径为1~3 nm,故将这类膜称为纳滤膜。纳滤膜可以截留糖类等低相对分子质量有机物和高价无机盐(MgSO4等),但对单价无机盐的截留率低(仅为10%~80%),具有相当大的透过能力。由于单价盐可以自由透过纳滤膜,使得膜两侧因离子浓度不同而造成的渗透压差远远低于反渗透膜。在相同通量条件下,纳滤膜所要求的驱动压力比反渗透膜要低得多。一般纳滤的操作压力为0.5~1.5 MPa。由于纳滤膜的这种独特分离性能,确定了它在水软化和低相对分子质量有机物纯化浓缩的地位。此外,纳滤膜能有效去除许多中等相对分子质量溶质,如消毒副产物的前驱物、残留农药和某些色素等,因而在水净化处理和脱色中得到广泛应用。  相似文献   

6.
采用锰砂/石英砂滤池与纳滤膜组合工艺处理含砷水,考察锰砂/石英砂、纳滤膜(NF90、HL)、锰砂/石英砂滤池与纳滤膜组合工艺对水中砷的去除效果.结果表明,三价砷(As(Ⅲ))和五价砷(As(Ⅴ))经锰砂/石英砂过滤后能得到很好的去除,原水砷浓度250 μg/L,出水砷浓度小于50μg/L;纳滤膜对五价砷(As(Ⅴ))的去除能力很高,能达到90%以上,但是对三价砷(As(Ⅲ))的去除率不理想,为40%~60%;锰砂/石英砂复合滤池与纳滤膜组合工艺对水中砷有很好的去除效果,出水砷浓度均小于10μg/L,是理想的饮用水除砷方法.  相似文献   

7.
饮用水中纳滤技术的应用与发展   总被引:5,自引:0,他引:5  
罗敏  王占生 《给水排水》2001,27(11):7-9
综述了纳滤膜在饮用水处理中的应用现状与未来的发展趋势 ,并提出了饮用水处理中纳滤膜的选择准则。  相似文献   

8.
《中国水利》2008,(10):82
技术简介 ①系统采用超滤膜(UF)和纳滤膜(NF)组件串联。对经过常规处理(混凝-沉淀-过滤-消毒)的饮用水进行深度处理; ②设备简单,运行方便,膜组件可以拆卸组装,运输到灾区作为应急饮用水处理的最后一道防线,可以有效地去除水中的病毒、溶解性有机物、盐类等。  相似文献   

9.
管道直饮水处理系统的优化研究硕士生 :王伟川 导师 :柯水洲(湖南大学土木工程学院  410 0 82 )对水质问题的发展历程及国内外饮用水水质标准作了简要介绍 ,分析了国内管道直饮水的现状 ,提出了管道直饮水水质标准 ,重点研究了管道直饮水的处理工艺及消毒方法的优缺点。分别以泉水和城市自来水为原水 ,通过生产性试验确定了用于管道直饮水净化的较优化工艺。试验研究的主要结论如下 :(1)“活性炭 +反渗透 +臭氧”是用于管道直饮水净化的较好工艺 ,能有效去除水中 (地下水或自来水 )的浊度、色度、CODMn及细菌等杂质 ,出水能符合《饮…  相似文献   

10.
采用几种材料分别进行苦咸水淡化试验,考察了不同试验条件下的处理效果,结果表明,几种材料中纳滤膜对苦咸水的处理效果最佳。探讨了影响纳滤膜脱盐效率的因素,研制了适合于农牧区使用的小型苦咸水淡化器样机。  相似文献   

11.
12.
Efficiency of membrane processes for taste and odor removal.   总被引:2,自引:0,他引:2  
The occurrence of tastes and odors (T&O) in drinking water is considered as one of the main problems by the drinking water companies. Thus, several treatment processes were developed over the years to control T&O including air stripping, activated carbon and oxidation using ozone. However, little information is available in the literature on the use of membranes for T&O removal. Therefore, the objectives of this paper are to present potential of membrane processes for removal of taste and odor causing compounds. Several membranes were tested including ultrafiltration (UF), UF combined with powdered activated carbon (PAC), nanofiltration (NF) and low pressure reverse osmosis (LP RO) membranes. The results of this study indicate that the combination of UF with PAC is effective for T&O control whereas the benefit of NF and LP RO remains unclear for T&O control.  相似文献   

13.
In the carwash industry, water recycling is necessary to be in accordance with present and upcoming environmental laws. As this is not possible with traditional techniques, membrane processes (like ultrafiltration (UF) and nanofiltration (NF)) are technically and economically evaluated in this study. Concerning the technical part, there needs to be a compromise between a high permeate permeability on the one hand and a high permeate purity on the other hand. Depending on the use of the purified wastewater, ultrafiltration (to recycle wastewater in the main wash cycle) or nanofiltration (to recycle wastewater in the rinsing step) would be the optimal choice. Concerning the financial part, the implementation of membrane processes in the wastewater purification installation is economically feasible, especially when expensive tap water is used as pure water. These positive evaluations imply that membrane processes can be useful to recycle wastewater in the carwash industry, on condition that the right membrane type (with the least membrane fouling) and the right process format (e.g., hybrid process of UF and/or NF with a biological treatment) is selected.  相似文献   

14.
Chemicals that are known or suspected of being endocrine disrupting chemicals (EDCs) have received increased attention over the past decade for their potential presence in drinking water sources. This study focuses on the development of a hybrid system that combines the advantages of nanofiltration (NF) and homogeneous catalytic oxidation, which include compactness, operational facilitation, high treatment efficiency, and selective reaction capability. Iron(lll)-tetrasulfophthalocyanine (Fe-TsPc) was employed as a homogeneous metal catalyst to degrade bisphenol-A (BPA), a representative EDC. The treatment efficiency of BPA as well as operational characteristics of the hybrid system was investigated to examine the applicability of this technique to decrease the concentration of EDCs in drinking water. Fe-TsPc homogeneous catalyst revealed a remarkable activity in degrading BPA under acidic condition. The high rejection of Fe-TsPc catalyst in the feed stream by the membrane for its large molecular weight (976 Da) and functional group (SO3(-) X4) allowed the continuous use of the catalyst for BPA oxidation reaction. The NF with Fe-TsPc/H2O2 hybrid system turned out to have higher BPA treatment efficiency comparing with the NF-only system since the hybrid system reduced BPA concentration in the feed stream by catalytic destruction of BPA as well as it mitigated concentration polarization on the surface of the membrane.  相似文献   

15.
Water supply for human consumption requires certain quality that reduces health risks to consumers. In this sense, the process of disinfection plays an important role in the elimination of pathogenic microorganisms. Even though chlorination is the most applied process based on its effectiveness and cost, its application is being questioned considering the formation of disinfection by-products (DBPs). Therefore, alternative disinfectants are being evaluated and some treatment processes have been proposed to remove DBPs precursors (organic matter. This paper reports the results of disinfection of a non conventional source of water (aquifer recharged unintentionally with raw wastewater) with peracetic acid (PAA) and ultraviolet radiation (UV) as well as nanofiltration (NF) followed by chlorination to produce safe drinking water. The results showed that a dose of 2 mg/L PAA was needed to eliminate total and faecal coliforms. For UV light, a dose of 12.40 mWs/cm2 reduced total and faecal coliforms below the detection limit. On the other hand, chlorine demand of water before NF was 1.1-1.3 mg/L with a trihalomethane formation potential (THMFP) of 118.62 microg/L, in contrast with chlorination after NF where the demand was 0.5 mg/L and THMFP of 17.64 microg/L. The recommended scheme is nanofiltration + chlorination.  相似文献   

16.
为解决印染废水的资源化处理问题,针对实际印染废水研究了以超滤和纳滤膜分离技术为核心的印染废水处理及回用工艺在工程上的可行性。实验结果表明:还原染料废水采用超滤系统处理,膜出水水质即能够满足印染厂内回用水质要求;活性染料废水通过纳滤浓缩能够获得较好的染料回收效果。采用双膜膜分离系统(UF+NF)能够使两种染料废水的污染物均得到明显去除,还原性染料废水的总悬浮物、COD、浊度和色度的去除率达到了100%、95.21%、92.86%和100%;活性染料废水上述各项指标去除率达到100%、82.85%、98.46%和99.43%。双膜膜分离系统适用于工业印染废水处理及染料回收,是资源化处理印染废水的发展方向。  相似文献   

17.
Three-bore hollow fiber charged nanofiltration (NF) membrane was prepared by interfacial polymerization (IP). The results showed that the flux and rejection of NF membrane prepared in this study increased with the increasing in the operating pressure. The water flux decreased and rejection for obvious dyes increased as the solute concentration increased. The separation factor for mixture of Xylenol orange/NaCl decreased when NaCl concentration in solution increased and could reach to as high as 18. In addition, three-bore hollow fiber charged nanofiltration membrane prepared in this study has excellent stability for strong acid (pH = 3), strong alkali (pH = 11) and high temperature solution (80 °C).  相似文献   

18.
A combined system using nano MgO and nanofiltration (NF) membrane was established to purify polluted water in this experiment. The turbidity, permanganate index, UVA254, colony counts and the concentrations of NO3-, NO2-, NH4+, Fe, Mn and Mg of the effluents from each unit of this combined system were measured to investigate the pollutant removal of this system. Based on the results obtained, the combined nano MgO-NF system could efficiently remove many kinds of pollutants in this experiment, including organic matter, nitrogen species, heavy metals, suspended solids and bacteria. And the effluents could meet the standard of drinking water. Furthermore, increasing the nano MgO dosage could not elevate the removal ratio of the pollutants, but only increase the Mg content of the effluent. Thus, 0.05 g L(-1) of nano MgO may be a suitable dosage for 2,000 L of polluted water treatment. Also, the operating pressure of NF membrane had no significant effect on pollutant removal when the operating pressure of NF membrane was increased from 0.3 to 0.9 MPa.  相似文献   

19.
Dyeing wastewater was post-treated by using nanofiltration (NF) and reverse osmosis (RO) membranes. To reduce membrane fouling, poly (vinyl alcohol) (PVA) with a neutral charge was coated on NF and RO membranes. The effect of surface charge and surface roughness on membrane fouling was investigated. Dyeing wastewater was pre-treated by using coagulation, activated sludge process, and MF process to investigate the effect of the pre-treatment on the membrane fouling. It is demonstrated that the extent of fouling is significantly influenced by the surface roughness and the surface charge on the NF and RO membranes. A membrane with a smooth and neutral surface was fouled less. The pre-treatment was essential for avoiding NF and RO membranes fouling. The quality of the final permeate was acceptable for water reuse.  相似文献   

20.
利用纳滤和反渗透膜深度处理工艺进行长江原水水质净化中试研究,工艺流程为长江原水→混凝沉淀→沙滤→颗粒活性炭→纳滤/反渗透,比较纳滤、反渗透膜工艺对污染物特别是微量有机物苯系物、三氯乙烯及消毒副产物等的去除效果。结果表明膜工艺预处理能够有效地去除原水的浊度和部分污染物,有利于纳滤、反渗透的稳定运行。纳滤膜工艺的最佳操作压力是0.4 MPa,此压力下产水量为250 L/h,回收率为24%,SO42-,Cl-,NO3-和总硬度的去除率分别为91.7%,85.4%,85.2%,89.3%;采用浓缩水回流能兼顾较高的回收率和良好的去除率。2种膜工艺对苯系物与三氯乙烯的去除率均在95.7%以上;对消毒副产物也有较好的控制效果,其中大部分的削减率在63.7%以上。与反渗透膜工艺比较,纳滤膜工艺具有较低的生产成本。纳滤膜工艺净化出水中可部分保留对人体有益的矿物质,使得净化后的出水成为优质健康饮用水。  相似文献   

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