五种预处理方式对超滤膜处理松花江水的效能比较

采用中试对比考察了不同预处理方式(包括混凝、砂滤、混凝-砂滤、高锰酸钾-混凝-砂滤、粉末活性炭)对超滤膜渗透性能及其对去除松花江水中污染物的影响.结果表明:以松花江水为原水,在超滤膜之前进行预处理是必要的.其中单独混凝会使膜通量降低,投加高锰酸钾使膜通量显著增加,并可延缓膜通量的下降速度,投加粉末活性炭对提高膜通量作用不大;不同预处理均能保证超滤膜出水浊度低于O.3 NTU,大于2 μm颗粒数少于10个/mL;此外,不同的预处理均能提高超滤膜对水中有机物的去除效果,高锰酸钾-混凝-砂滤-超滤对DOC、UV254的去除率分别为37.5%、28%.     

粉末活性炭—超滤组合工艺处理长江陈行原水

以长江陈行水库原水为研究对象,探讨了粉末活性炭—超滤组合工艺对水中CODMn、UV254、浊度、氨氮等去除效果,评价投加粉末活性炭后超滤膜跨膜压差(TMP)的变化情况.结果表明:超滤膜出水CODMn均值为1.10 mg/L,平均去除率为48.7％,UV254均值为0.016 cm-1,平均去除率为76.2％;组合工艺对水中氨氮具有一定的去除效果,对总铁、总锰去除效果显著,出水浊度保持在0.031 NTU以下.粉末活性炭投加于沉淀池之前,对于改善出水水质、减轻膜污染起到了较好的效果.     

强化混凝技术处理东太湖原水研究

在常规混凝工艺确定的最佳处理条件下,考察了单独高锰酸钾(KMnO4)和次氯酸钠(NaClO)预氧化、单独投加粉末活性炭(PAC)以及KMnO4和PAC联用对混凝处理东太湖原水的强化效果。结果表明,聚氯化铝和硫酸铝的最佳投加量分别为20mg/L和30mg/L,聚氯化铝的混凝效果明显优于硫酸铝;投加KMnO4对浊度、CODMn和UV254的去除均有一定程度提高,但不利于原水氨氮的去除;投加PAC有显著的强化混凝作用,各指标去除率均有所提高;KMnO4和PAC联用能进一步提高水中UV254的去除率;预氧化大大提高了混凝对氨氮的去除效果,投加1mg/L NaClO对氨氮去除率可达100%。     

高锰酸钾强化混凝—陶瓷微滤膜集成工艺处理水源水研究

采用高锰酸钾强化混凝—陶瓷微滤膜集成工艺处理水源水,主要考察了不同高锰酸钾投加量对集成工艺中膜污染状况和出水水质的影响。结果表明,在混凝过程中投加高锰酸钾进行预氧化,与单独的混凝—陶瓷微滤膜集成工艺相比,膜污染速率下降,降低了不可逆膜污染;出水水质得到一定程度的提高,其中UV254、CODMn、DOC、TN去除率分别提高了约3%、10%、5%、16%。另外,出水浊度<0.1 NTU,出水颗粒数水平也得到了很大改善。     

水厂示范工程滤池处理排涝期水质的试验研究

针对排涝期水中高氨氮和有机物污染问题,研究了示范工程滤池联用曝气系统对水中氨氮、亚硝酸盐氮、CODMn和UV254的去除效果。结果表明高压增氧曝气对增加滤池水中的溶解氧含量最有效,活性无烟煤和活性炭滤池对污染物的去除效果显著优于砂滤池,高压增氧曝气与活性无烟煤滤池联用对污染物的去除效果最好,对氨氮、亚硝酸盐氮、CODMn和UV254的平均去除率分别达到73.57%、87.93%、42.65%和37.21%。     

以IBAC为核心处理洗浴废水的试验研究

根据洗浴废水的水质特征,采用原水→混凝沉淀-过滤→固定化生物活性炭(Immobilized Biological Activated Carbon,IBAC)→微滤膜(MF)→UV消毒→出水的工艺流程.混凝沉淀-过滤物化预处理单元可以有效地减少洗浴废水中的各类污染物.IBAC生化处理单元,实现有机污染物、LAS、浴臭等有效去除,是保证出水合格的根本措施.微滤膜发挥物理截留作用、UV消毒杀死细菌和总大肠菌群.出水水质达到＜城市供水水质标准＞(CJ/T 206-2005).     

炭砂过滤-膜处理组合工艺中试研究

对预臭氧-混凝沉淀-炭砂双层过滤-微(超)滤组合工艺进行了中试研究,试验结果表明该处理工艺可有效去除浊度,保证出厂水浊度在0.1NTU以下及出水的微生物安全性,对氨氮的去除率可达95%左右,CODMn去除率可达50%左右.     

生物预处理后续工艺中生物砂滤柱的性能研究

对黄浦江原水生物预处理后续工艺中的生物砂滤柱性能进行研究。在不同氨氮浓度的工况下,探讨了生物砂滤柱对氨氮、有机物等指标的去除,分析了生物砂滤柱的生物活性,同时总结了主要设备的设计运行参数。通过中试运行效果表明:在进水中平均氨氮浓度为1.73 mg/L,停留时间6.8 min下,氨氮平均去除率达到91.6%,同时CODMn和UV254的去除率分别为7.9%和7.5%。     

臭氧-生物活性炭控制有机物和消毒副产物研究

南方某水厂采用的臭氧-生物活性炭给水深度处理工艺稳定运行了6年,为了解工艺长期运行过程中在活性炭性能指标下降后,是否还能有效地去除有机物和消毒副产物,开展了试验研究。重点考察臭氧-生物活性炭对水中有机物和氯化消毒副产物的去除效果,通过与常规处理出水水质的对比,探讨其去除有机物和消毒副产物的优势。结果表明,臭氧-生物活性炭是一个长期有效的去除有机物和氯化消毒副产物的控制手段。该工艺对CODMn、TOC、UV254的去除率分别为43.2%、24.0%、58.8%;对THMsFP去除率为40.1%;对三氯甲烷和三氯乙醛的去除率分别达到54.5%和70.7%。在臭氧-生物活性炭组合处理工艺中,活性炭池是去除有机物和消毒副产物的关键工艺。     

臭氧—平板陶瓷膜新型净水工艺中试研究

为应对饮用水源受到的有机物和氨氮的复合污染,对混凝—臭氧/陶瓷膜—活性炭池新型净水工艺进行中试研究。结果表明,臭氧可以在线控制膜污染,臭氧投加量2mg/L,间歇提高臭氧投加量至5mg/L时,陶瓷膜跨膜压差在通量100L/(m2·h)下运行5d后增长小于2kPa。臭氧促进了陶瓷膜对颗粒物的去除,投加臭氧时膜出水中大于2μm粒径的颗粒数低于10个/mL。新型净水工艺能有效去除受污染原水中的有机物和氨氮,工艺对UV254的去除率为65%~95%,CODMn去除率为71%~98%,出水CODMn低于0.5mg/L;原水氨氮3.5mg/L时,工艺出水氨氮0.1mg/L,且无亚硝态氮积累,氨氮基本转化为硝态氮。此外,新型净水工艺对卤乙酸生成势的去除率高于85%,大大提高了工艺出水的安全性。实现了传统工艺与深度处理工艺的叠加集成,对水厂升级改造具有重要意义。     

Correlations between silt density index,turbidity and oxidation-reduction potential parameters in seawater reverse osmosis desalination

The reverse osmosis method is one of the most widely used methods of seawater desalination at present.Hydrophilic and desalting membranes in reverse osmosis systems are highly susceptible to the input pollutants.Various contaminants,including suspended organic and inorganic matter,result in membrane fouling and membrane degradation.Fundamental parameters such as the turbidity,the amount of chlorine injection,and silt density index(SDI)are the most predominant parameters of fouling control in the membranes.In this study,the operation system included a water intake unit,a pretreatment system,and an RO system.The pretreatment system encompassed a clarifier,a gravity sand filter,pressurized sand filters,and a cartridge filter.The correlation between the amount of chlorine injection in terms of the oxidation-reduction potential(ORP)and the SDI value of the input water was investigated at a specified site next to the Persian Gulf.The results showed that,at certain intervals of inlet turbidity,injection of a certain amount of chlorine into the raw water has a distinct effect on the decrease of SDI.     

纳滤膜净化地下水时预处理工艺的选择研究

针对不同地下水水质,分别以活性炭、石英砂、锰砂进行预处理,采用纳滤膜工艺制取优质饮用水。旨在为不同地区、不同水质的地下水净化探索一种更为有效的预处理方法。研究表明,活性炭更适合用作有机污染物含量较高的浅层地下水的预处理;而石英砂、锰砂更适合用作铁、锰含量较高的深层地下水的预处理。也可以将几种预处理工艺联用,以获得更好的效果。     

Effects of flocculent aggregates on microfiltration with coagulation pretreatment of high turbidity waters.

Immersed membrane systems, and those with in-line coagulation, have been extensively applied in drinking water systems. Sedimentation is usually replaced by membrane processes in both systems. In these systems, voluminous flocculent aggregates formed during coagulation could be potential foulants. When raw waters with high turbidity are introduced, particle loadings to membrane due to coagulation pretreatment are enormous and thus could increase fouling. In general, during the rainy season, the turbidity of the Han River water, which supplies drinking water for the City of Seoul, Korea, is more than a hundred times higher than usual. Therefore, effects of floc on membrane fouling were investigated with highly turbid waters. Two turbidity concentrations, 40 and 200 NTU, were formulated by the addition of kaolin (used as a natural particle surrogate) to the Han River raw water. The results showed that the flux decline behaviours of the highly turbid waters were different from those of natural raw water. Coagulation pretreatment was very effective at reducing membrane fouling. Flocculent aggregates showed a negative effect on the flux decline but a positive effect on the membrane cleaning efficiency.     

集成膜技术工业废水深度处理回用试验研究

试验采用超滤+反渗透集成膜分离技术,目的是研究其集成工艺处理有色冶金工业废水的合理性和可行性。超滤试验主要测试了在不同水质情况下超滤膜的相关运行参数,主要测定指标有超滤系统的进水、产水和反冲洗水的水量,运行压力,出水浊度,SDI值等;反渗透试验主要测定指标有电导率,反渗透系统的进、出水量,运行压力等。试验研究表明:以预处理+超滤+反渗透组成的集成膜处理工艺,能够满足有色冶金工业废水处理回用的要求。     

舰船反渗透海水淡化膜法预处理系统在线清洗方法的研究

利用连续处理高浊度海水试验,比较了舰艇反渗透海水淡化预处理系统分别采用气水在线双洗和药剂加气在线清洗时,滤过水SDI、浊度以及系统跨膜压差的变化趋势。结果表明,两种在线清洗方法都能够使系统滤过水SDI≤5、浊度≤1.0 NTU,达到舰船反渗透海水淡化装置的进水水质要求;但药剂加气在线清洗系统滤过水SDI多介于2.0～2.5之间,浊度≤0.75 NTU,系统跨膜压差≤43 kPa,波动范围较小,变化趋势平缓,更有利于舰船反渗透海水淡化膜法预处理系统的稳定运行。     

Foulant characterization of the NF membranes with and without pretreatment of biologically treated wastewater.

In this study, different pretreatment methods such as ferric chloride (FeCl3) flocculation and powdered activated carbon (PAC) adsorption were evaluated in terms of their capability in removing effluent organic matter (EfOM) and the characteristics of the foulants on the NF membranes. A detailed experiment was conducted with two NF membranes (NTR 729HF with MWCO 700 daltons and LF 10 with MWCO 200 daltons). With pretreatment, the concentration of organic matter on the membranes decreased to 5.671 x 10(-3) (NTR 729HF) and 4.940 x 10(-3) (LF 10) mg EfOM/cm2 of membrane from 6.372 x 10(-3) (NTR 729HF) and 4.979 x 10(-3) (LF 10) mg EfOM/cm2 of membrane. The MW of the solute fraction of biologically treated sewage effluent (BTSE) ranged from 250 daltons to about 3573 (the most important being 250-520 daltons). The weight-averaged MW values of the foulants on the NTR 729HF membrane reduced from 304 daltons without pre-treatment to 208 daltons with pretreatment. In the case of EfOM, the small molecules (MW 300 to 500 daltons) are mainly responsible for the membrane fouling. Thus, the MW distribution of organic matter in the effluent and in the foulant can be used as a representative tool to evaluate the efficiency of pretreatment and NF and in the selection of their operating conditions.     

微滤膜法饮用水处理工艺中膜污染控制的研究

采用150 m3/d的微滤膜法饮用水处理中试研究了膜污染的控制方法,包括反冲洗、混凝预处理以及在线的通量维护措施--EFM(Enhance Flux Maintenance).结果表明,单独采用水反冲洗时,膜比通量的恢复效果较差,采用气水联合反冲洗时效果明显好转,膜污染速率降低为原来的44%.混凝预处理能够很好地控制膜污染,其主要作用在于降低滤饼层阻力和减轻不可逆膜污染.在研究的范围内,混凝剂投加量越高,对膜污染的控制作用越好.EFM能够阶段性地去除膜污染,有效地恢复膜比通量,因而能够显著地延长化学清洗周期,减少化学清洗频率.     

在线混凝-超滤联用工艺用于小城镇给水的应用研究

采用在线混凝-超滤联用工艺对某水塘水进行中试研究.试验结果表明,将常规处理作为超滤的预处理时,膜压差增加迅速,无法保持稳定运行.将在线混凝作为超滤的预处理时,膜压差增加缓慢.通过比较不同的混凝剂抑制压差和去除有机物的效果,发现聚硫酸铁均优于聚氯化铝.次氯酸钠和高锰酸钾预氧化的试验结果表明,尽管高锰酸钾去除有机物和三氯甲烷生成潜能的效果较好,但膜压差增加较快.在线混凝-超滤联用工艺处理后出水的CODMn可低于3 mg/L.     

UF-RO组合工艺处理循环冷却排污水的研究

在电力循环冷却排污水回用系统中,采用UF-RO组合工艺对循环排污水进行去浊除盐.通过现场试验,考察了超滤在循环冷却排污水回用中作为反渗透预处理的可行性;在工程实践中确定了系统实际运行工艺参数并对运行成本进行了分析.该工艺为循环冷却排污水的再利用开辟了一条新途径,既节约了水资源,又减少了环境污染.     

Membrane-flocculation-adsorption hybrid system in wastewater treatment: micro and nano size organic matter removal .

Cross flow microfiltration with in-line flocculation reduces the fouling of membranes thus leading to high quality product water. A detailed experimental study conducted with an artificial suspension (particle size distribution similar to that of surface water) revealed that the filtration rate can be increased by several times by adopting in-line flocculation. In-line flocculation-microfiltration is therefore an attractive technique to reduce internal clogging while improving the permeate flux significantly. A detailed ultrafiltration (UF) study was conducted with biologically treated sewage effluent with pretreatment by flocculation and powdered activated carbon adsorption. The TOC removal by the NTR 7410 UF membrane alone was 43.6%. The TOC removal increased significantly by the use of pretreatment: 69.3% by flocculation and 91% by flocculation followed by adsorption. The organic colloidal portion (between 3,500 dalton and 0.45 microm) in the biologically treated effluent was removed up to more than 65% by the pretreatment of flocculation. The molecular weight of the biologically treated effluent ranged from 250 to about 3,573 dalton with the highest fraction in the range of 250-845 dalton. By the incorporation of pretreatment, the majority of both large and small molecular weight organic matter was removed. This hybrid system led to practically no filtration flux decline in membrane filtration.