盐泥除盐的膜清洗技术研究

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膜法处理高盐度废水的初步研究

膜法处理高盐度废水的初步研究金可勇1 ,周勇1 ,郑宏林1 ,刘立芬2(1 杭州水处理技术研究开发中心浙江杭州 310012)(2 浙江工业大学, 浙江杭州 310012)摘要：高盐度废水用普通的生化法或膜法的处理效果都不理想或运行费用太高。

本文研究是结合纳滤膜法处理与生化处理的组合工艺处理该类废水，达到盐水回收的目的。

关键词：高盐度废水; 纳滤膜; 生物处理; 组合工艺目前, 水资源的短缺和水体污染已严重制约了我国的经济发展、社会进步和人民生活水平的提高，解决水体污染问题非常迫切。

2003年我国每生产1亿元GDP需排放20余万吨废水，这个指标比1990年增长84.8%。

环境污染的加剧，又不断加大治理环境污染的费用支出。

为此我国每年环境污染治理投资总额数千亿元，约占全国GDP的2%，从中可以看出水污染对我国的影响非常大。

在一些干旱地区和沿海地区，水资源短缺特别是水质性短缺问题更为严重，为了缓解淡水资源日益紧缺的局面，一些沿海地区已经推行海水直接利用于工业生产和生活用水，如在香港冲厕海水量已达413×105m3/d，约为全港淡水总用量的17%，这些活动导致了排放废水中含有大量的无机盐。

另外，一些工业如杀虫剂、除草剂、有机过氧化物、制药和染料等化学制造业，淹制品、海产品加工厂等，其生产废水中都含有大量的无机盐。

含盐废水的排放带来十分严重的环境污染，特别是工业含盐废水，除受到本身高浓度盐的限制外，还含有大量的有毒、难降解有机物[1-7]。

这些废水都由于含盐量高用传统的生化法不能处理或处理后达不到排放标准，更不要说盐水回收的问题了。

对于该类废水如采用膜法处理一般有反渗透、纳滤、电渗析等方法。

本研究针对该类废水用普通生化法处理效果不理想而用膜法处理又存在膜污染的技术难题，提出采用低脱盐耐污染复合膜来处理该类废水的技术。

由于是低脱盐的复合膜，产水与原水盐浓度差距比较小，解决了操作压力过高的问题；而对于用膜法处理该类废水最为关键的膜污染问题，本研究通过制备新型纳滤膜，研究其对高盐度废水的处理效果。

脱盐中清洗纳滤膜的新方法

An innovative backwash cleaning technique for NF membrane in groundwater desalination:Fouling reversibility and cleaning without chemical detergentWenli Jiang a ,b ,Yi Wei a ,b ,Xueli Gao a ,b ,⁎,Congjie Gao a ,b ,Yuhong Wang ca Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Ocean University of China,Qingdao 266100,Shandong,Chinab College of Chemistry and Chemical Engineering,Ocean University of China,Qingdao 266100,China cNational Center of Ocean Standards and Metrology,Tianjin 300112,ChinaH I G H L I G H T S •A novel cleaning method was developed.•This method was used in nano ﬁltration membrane cleaning for the ﬁrst time.•Direct osmosis backwash was worked by injection of high salinity solution.•There was a strong driving force to lift and sweep the foulants from membrane.•The permeate water ﬂux recovery was more than 99.78%with cleaning for 10min.a b s t r a c ta r t i c l e i n f o Article history:Received 2November 2014Received in revised form 17December 2014Accepted 18December 2014Available online 29December 2014Keywords:Membrane fouling Nano ﬁltration Direct osmosis High salinityBackwash cleaningMembrane fouling is the main problem during the nano ﬁltration (NF)process of brackish water desalination due to the existence of natural organic matter,especially humic acid (HA).Moreover,the conventional membrane cleaning method would do great harm to the environment because large amount of chemicals were employed.In order to control organic fouling,a novel cleaning method via direct osmosis backwash (DOBW)by injecting high salinity (HS)solution was developed.Different operating conditions for HS-DOBW technology in the actual process were systematically investigated.The results demonstrated that there was a strong driving force to lift and sweep the foulants from the membrane surface which would be carried over to the brine.The optimal conditions in terms of HS (150kg/m 3NaCl solution)ﬂow rate of 0.121L/min were selected for the subsequent experiments.The results showed that the fouling could be almost fully reversible (more than 99.78%permeate water ﬂux recovery),and the membrane needed to be cleaned for about 10min because of the appearance of HA on membrane surface at the fouling time of 24h.Most importantly,the HS-DOBW technology is very effective in keeping the membrane continuously clean and ensuring stable permeate production.©2014Elsevier B.V.All rights reserved.1.IntroductionPotable water scarcity is one of the greatest challenges around the world,because of the increasing water demand and the decreasing availability of pure natural water resources [1,2].Especially in some hydroponic inland places,the groundwater is rich in ﬂuorine,arsenic and salinity.Nano ﬁltration (NF)is a pressure driven membrane-based desalting process and is considered world-wide as one of the most promising technology among various water treatment processes [3].Groundwater desalination with NF membrane,an effective means to obtain fresh water,eases the worries about the water resource crisis.Galanakis et al.[4]have successfully conducted NF of brackish ground-water using a polypiperazine membrane with a high mineral fouling resistance.This study contributed to the development of NF applica-tion for the production of low cost drinking water in touristic regions (i.e.,islands,coasts and hotel areas),where water de ﬁciency is mainly a seasonal but growing problem.However,membrane fouling is an unavoidable long-standing prob-lem which has a strong impact on the ef ﬁciency of this process.When fouling occurs on the membrane surface the permeation decreases,the trans-membrane pressure increases,the permeate quality may de-crease and the membrane may be damaged [5].In order to minimize NF plant deterioration due to fouling,the fouled membranes are ad-dressed through extensive pretreatment and periodic chemical cleaningDesalination 359(2015)26–36⁎Corresponding author at:Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Ocean University of China,Qingdao 266100,Shandong,China.E-mail addresses:gxl_ouc@ ,haichaodiyin123@ (X.Gao)./10.1016/j.desal.2014.12.0250011-9164/©2014Elsevier B.V.All rightsreserved.Contents lists available at ScienceDirectDesalinationj o u r n a l h o m e pa ge :ww w.e l s e v i e r.c o m /l o c a t e /d e s a land disinfection[6–9,27].In any case,due to the downtime resulting from frequent NF operation stoppage,these widely used methods will not only result in low effectiveness of production and high cost of cleaning agents,but also create environmental issues related to the waste chemical disposal.Therefore,it is strongly desired toﬁnd a new method to reduce or even eliminate chemical cleaning.Pressure-driven backwashing,which is a common practice in microﬁltration and ultraﬁltration processes,is an effective means of fouling control.But it is not applied in NF membranes,as the high back-pressure may rupture the composite membranes[6,10].Spiegler and Macleish[6,11]proposed the means of introducing an osmotic driv-ing force for backwashing.Osmotic backwashing can be induced when the feed-side osmotic pressure exceeds the applied hydraulic pressure across the membrane.Development of direct osmosis(DO)technology has been in-creasingly attractive for backwash cleaning of reverse osmosis(RO) because it is highly efﬁcient and eco-friendly[11].Spiegler,Macleish, Semiat's group,Avraham and Liberman et al.[3–6,12–19]have al-ready studied DO technology.Spiegler and Macleish[4,11]investi-gated DOBW of RO membranes and they found thatﬂux of the RO membrane fouled with ferric hydroxide could be restored after DOBW.However,it took at least30min for each backwash opera-tion.Ando et al.[20,21]implemented a permeate back pressure in the range of0.05–0.3MPa for backwash of a spiral wound RO mem-brane module.Rychen et al.[22]studied a new DOBW process run-ning with no pressure supplied at the permeate side.And then Semiat's group[5,13,23]conducted fundamental research on this conclusion.They studied the effects of feed concentration,backwash time and feed operating pressure on the DOBWﬂow rate.Soon after-wards,Avraham et al.[5]reported that there were two distinct stages for the permeate backﬂow rate vs.time.In Stage I,the back-washﬂow rate was the highest at the beginning and sharply declined with time.In Stage II,the backwashﬂow rate then slowed down until leveled off[4,13].They suggested that the DOBW period should be controlled within Stage I,maybe less than20s.And theﬂux of the RO membrane newly fouled by CaCO3could be resumed to its origi-nal level after the DOBW with0.5%NaCl solution over20s.Liberman[24–27]reported a new DOBW technology for RO mem-brane cleaning,where a high salinity solution(HS)was injected into the feed water over a few seconds.It was reported that in a seawater RO desalination process,a super-saline solution made of17%NaCl could be injected to create a net driving force of55bar for the DOBW process[4,26].And now with the development of this technology,it had been applied in four brackish water RO trains at Dshanim Factory in Israel[28].Hitherto a lot of studies on the DOBW method have been con-ducted and all of the above-mentioned researches are about RO membrane.However,there is no study on the DOBW method used for NF membranes.Both RO and NF are all pressure-driven processes, so the HS-DOBW technology may be applied in the NF membrane cleaning.The study of its application in potable water production from salinity-rich groundwater with NF membrane has not been re-ported.Therefore,previous studies provide a preliminary indication regarding the potential of employing the HS-DOBW technique for NF membrane cleaning.In this paper,the main purpose is to investigate the HS-DOBW mechanism for a singleﬂat sheet NF membrane and identify its main parameters.A simpliﬁed mathematical model was developed to predict the DOBW stage accurately and veriﬁed by corresponding experiments which is possible to understand and control the back-wash process of zero-applied pressures.Effects of major parameters and operating conditions were systematically investigated and opti-mized via a laboratory-scale operation for future practical imple-mentation in the case of zero-applied pressure,where osmosis forces alone drive the DOBW process,i.e.,atmospheric pressures al-lows on both sides of the NF membrane.2.Theory2.1.Driving force of the HS-DOBW processFig.1illustrates a comparison of the driving force in NF and HS-DOBW processes.Just like reverse osmosis(RO),NF is also a pressure-driven process.And the pressure is provided by exoteric power energy. Unlike NF,osmosis or FO or DO process is driven by the different osmo-sis pressures between two solutions separated by a semi-permeable membrane[29].The semipermeable membrane allows water to sponta-neously pass through it from higher water chemical potential side to the lower side,i.e.,passage of water is from the lower salt concentration side to the higher one because the lower the salt concentration is,the higher the water chemical potential is,which phenomenon was observed in1748[16].And the theoretical osmosis pressureΠof a salt solution can be calculated using the Van't Hoff Eq.(1).Π¼nc∅RTð1Þwhere n is the number of ions;c is the salt concentration(M),ϕis the osmosis coefﬁcient;R is the universal gas constant (0.082057L·atm·K−1·mol−1),and T is the temperature(K).2.2.Simplest mathematical modelThe present simplest mathematical model together with experi-mental data that were assigned to point at two backwash stages com-prises the backwash mechanism.Measurable variables of the DOBW process were needed to verify the theory[23].One of these variables was the DOBWﬂux through the membrane,dV/dt′:dV t0ÀÁdt0¼A m DdÂ106∂C0;tðÞ∂yð2Þwhere A m(m2)was the membrane area,D(m2/s),d(m),t'(s)and V(t') (mL).C,t and y were dimensionless.A second measurable variable of the DOBW process was the DOBW accumulated volume,V(t'),entering the feed channel at a dimensional time,t'.V(t'),obtained by integrating Eq.(2)with DOBW time,t':V t0ÀÁ¼A m dÂ106Zt∂C0;tðÞ∂y dt:ð3ÞEq.(3)was the main outcome of the DOBW model.It may be applied to experimental data sets for the model's veriﬁcation,predictability and further understanding,followed by control of the DOBW process.Eq.(3)parison of the driving force in NF and HS-DOBW processes.27W.Jiang et al./Desalination359(2015)26–36has one adjustable parameter,α,which may be determined by ﬁtting Eq.(3)to a speci ﬁc data set.2.3.Foulant lifting and sweepingFig.2shows a schematic of foulant accumulation in NF process and foulant lifting and sweeping during HS-DOBW cleaning [16,28].The ex-perimental situation that underlined the present model is as follows:the DOBW process starts as soon as the NF stops.Physically,after HS solution is injected into the feed water over a few seconds,the start mo-ment of the backwash process is when the net applied pressure drops below the osmotic pressure,Δπ.The HS solution enters the feed channel like a wave which occupies one or two membrane elements and moves towards the brine outlet.This is the moment at which the permeate water start to diffuse through the NF membrane and through the CP layer into the feed region,and then drain away [13].As a result,the foul-ing and/or scaling components are lift up vertically from the membrane surface.Meanwhile,velocity of the HS solution in the feed channel grows on its way to the brine due to the permeate “up ”suction,which induces an additional horizontal force to ﬂush the feed bi-nation of the lifting up with the increased velocity of HS solution pro-vides both stripping and sweeping effects to effectively clean the membrane surface and remove the foulants from the feed spacer.The water,when transfers through the membrane and CP layer,dilutes the salt concentration subject to diffusion and ﬂow laws while possibly removing the fouled layer.It was reported [1]that there were two distinct stages for the permeate back ﬂow rate vs.time.The ﬁrst backwash stage,characterized by high backwash ﬂow rate,ends when the salt concentration in the CP layer becomes lower than the salt bulk concentration.In Stage II,the backwash ﬂow rate then slows down until leveled off and water keeps diffusing into the feed space against the salt concentration.When no water feed to the membrane,it is reasonable to assume that time dependent water concentration in the feed side of the membrane is continuously reduced towards asymptot-ically pure water level.At the same time,transient process of salt con-centration dilution continues at the feed side.3.Experiments3.1.Reagents and NF membranesAll of the reagents were analytical grade except NaCl,and deionized water (DIW)was used throughout.HS solutions were prepared with in-dustrial grade NaCl.The NF membranes employed in this study were purchased from Zhejiang Mei Technology Co.,Ltd (China).The membranes employed in this experiment were installed in a laboratory-scale NF stack purchased from Shandong Tianwei Mem-brane Technology Co.,Ltd (Shandong,China).The main characteristics of the membranes are listed in Table 1.boratory-scale experimental set-up and synthetic groundwater qualitySchematic diagram of the fouling and subsequent HS-DOBW cleaning experiments performed with the NF-3A membrane in a laboratory-scale cross-ﬂow test unit was shown in Fig.3.The membrane test unit was equipped with a feed reservoir,a pressure vessel containing the mem-brane module,a circulation and pressurization pump with a security value and two pressure gauges,a thermometer for temperature measure-ment in the circulation reservoir [30]of a membrane cell,an automatic circulating cooling device for temperature control,and a ﬂow meter on the feed water pipe.A HS tank,a DIW tank and two peristaltic pumps were added for the process of HS-DOBW.The membrane cell was a rect-angular plate-and-frame unit,containing a ﬂat membrane sheet placed in a rectangular channel of 12.6cm 2effective membrane area.Both perme-ate and retentate were recirculated.The cross ﬂow velocity and the oper-ating pressure were adjusted by using a bypass valve in conjunction with a back-pressure regulator.In this paper synthetic groundwater was prepared according to the ratio of each ion in groundwater in northwest China,and the main ions in the synthetic solution and their corresponding concentrations are shown in Table 2.3.3.Analytical methodsAll the membrane samples were dried at 303.15K in hood for 24h.Subsequently,many relevant tests were measured.The contamination degree of NF membrane and cleaning ef ﬁciency of HS-DOBW method were measured with attenuated total re ﬂectance-Fourier transform in-frared spectroscopy (ATR-FTIR),energy dispersive spectrometer (EDS)and atomic force microscope (AFM).Permeate ﬂux recovery was also tested to demonstrate the cleaning ef ﬁciency of the novel technique.In the whole experiment,all samples were diluted to suitable levels for analysis.The content of arsenic in permeate samples was analyzed by using the AFS-230dual-channel atomic ﬂuorescence spectropho-tometer.Each sample was measured ﬁve times,so as to get more accu-rate results.The salinity was analyzed by using a conductivity meter (DDS-307A).Table 1The main characteristics of the NF membranes.ItemNF-3AUnit Type bFlat sheet membrane –Material bPolyamide –Surface charge b Negative –NaCl rejection b 38.0%MgSO 4rejection b 99.5%DIW permeability a 57.84L·m −2·h −1Operation pressure b 15–27kg Operation pH b2.0–10.0–Cleaning temperature b54°CNF test condition:NaCl 2g/L &MgSO 42g/L in water at 1.0MPa.aThe values were measured in the study.bInformation was provided by themanufacturer.Fig.2.Schematic of NF:foulant accumulation and HS-DOBW cleaning:foulant lifting and sweeping.28W.Jiang et al./Desalination 359(2015)26–363.3.1.ATR-FTIR analysisIn order to investigate the changes in chemical bonds in membrane surfaces,ATR-FTIR (Tensor 27,BRUKER OPTIK GmbH)was employed.The spectra were recorded in the range of 600–4000cm −1.3.3.2.SEM –EDS analysisThe membrane samples were cut into 6mm ×6mm size and coated with gold powder in the surfaces by a sputter coating machine before the observation of SEM –EDS (XL 30,Philips).The images of membrane surface were taken by SEM,and the surface element contents were analyzed by EDS.To get the average values,5different sites on each of three membrane samples prepared under the same fouling conditions were tested for the element contents [31].3.3.3.Roughness measurementAFM was used to measure the roughness of the membrane surface and examine the cleaning ef ﬁciency.The force measurements were carried out with a NanoScope 3D multimode AFM controller (Veeco Metrology Group/Digital Instruments).Measurements were per-formed in tapping mode with etched silicon TESP probes (spring constant 42N/m).Resolution of 512×512data points at 1Hz per image was used to collect the images.Membrane samples were cut into 10mm ×10mm size and then were put onto the substrate to be observed.A high accuracy morphology diagram of the membrane surface could be achieved and it re ﬂected the ion repulsion between the membrane surface and the probe.Then the roughness of the membrane surface and the degree of pollution could be reached.3.3.4.Permeate ﬂux analysisFlux (J )is the volume of permeate (V )collected per unit membrane area (A )per unit time (t ),which is calculated as:J ¼V =At :ð4ÞPermeate samples were collected for arsenic concentration and sa-linity determination and the membrane permeate ﬂux was measured at speci ﬁed time intervals.In order to assess the cleaning ef ﬁciency of HS-DOBW method,ﬂux recovery ratio (FRR)was calculated based on Eq.(5).FRR %ðÞ¼J w −J f wJ iw −J f wÂ100ð5Þwhere J iw is the pure water ﬂux before fouling;J fw is the pure water ﬂux after fouling;and J w is the pure water ﬂux after cleaning.Pure water ﬂux of membrane before and after fouling was measured.It was measured again after chemical cleaning.And all the pure water ﬂuxes were mea-sured under applied pressure of 1.0MPa,cross-ﬂow velocity of 1L/min,and temperature of 20.0±0.3°C.123450.81.01.2J / (L /m 2/h )Time / (min)Fig.4.Effects of HS and DIW ﬂow rate on cleaning ef ﬁciency.Table 2The main compositions in the synthetic groundwater.Main parameters Concentration Unit K +7.500ppm Na +882.9ppm Ca 2+58.92ppm Fe 3+0.375ppm Cl −653.2ppm SO 42−1271ppm NO 3−0.605ppm Mg 2+61.00ppm HCO 3−108.8ppm As(V)0.7ppm HA30ppmFig.3.Schematic experimental unit for NF fouling and cleaning.29W.Jiang et al./Desalination 359(2015)26–363.4.Membrane fouling and cleaning protocolsEach backwash experiment was conducted after running the exper-imental system for about 15min to assure steady state NF operation.Backwash time starts at the stop moment of the NF process,by stopping the applied pressure as quickly as possible,to minimize the shift time between NF and backwash processes.Several operation conditions such as HS-DOBW feed-ﬂow rate of both draw solution and feed solu-tion,valence state of ions,concentration of HS,the moment to start cleaning and the duration time.Three simple steps were added for HS-DOBW treatment orderly:(1)close the permeate valve V P ,concen-tration valve V C and feed ﬂow valve V F to pause the NF process (full lines in Fig.3);(2)open valve V H ,V HE and V D ,V DE over the desired time to inject HS and DIW into the NF membrane module by two peri-staltic pumps (BT/101S,Baoding Lead Fluid Technology Co.,Ltd,China)to start the HS-DOBW process (dotted lines in Fig.3);and (3)re-sume the normal NF operation via opening V P ,V C and V F after comple-tion of a HS-DOBW treatment.It should be pointed out that one to four conditions were tested in one day during the HS-DOBW trials for optimization of operating conditions and the ef ﬁciency of HS-DOBW method on NF fouling control would be validated in a long-term contin-uous plant operation in the next study.4.Results and discussion4.1.Optimization of operating conditions for HS-DOBW treatment 4.1.1.Effect of HS-DOBW feed-ﬂow rate on permeate rateFig.4summarized the results of a set of experiments which tested the in ﬂuence of the HS and DIW ﬂow rate.A HS-DOBW run was operat-ed using a HS solution and DIW at a certain ﬂow rate.After the system reached a steady operation,the backwash process was operated for each ﬂow rate.It could be observed that the permeate ﬂux of DIW through the membrane decreased dramatically with the cleaning timefrom 0to 2min and then decreased gently as the cleaning time increased.The reason for this behavior was related to a concentration polarization (CP)effect on the membrane wall.Then the high salinity solution was diluted by the backwash permeate water with cleaning time and the backwash driving force was reduced subsequently.It made no difference among different ﬂow rates by reason of their ana-logical performances.Taking into consideration economic and other fac-tors comprehensively,the ﬂow rate of 0.121L/min was selected for the subsequent experiments.4.1.2.Selection of HS solutions on permeate rateOsmotic pressure (Π)of salt solution was calculated according to Eq.(1)with known density,so as to investigate the effect of valence state on HS-DOBW cleaning ef ﬁciency and obtain a feasible HS solution.We could clearly see the results in Table 3that the dose of NaCl was the least under the condition of producing the same osmotic pressure.Apparently,the ion quantity of Na 2SO 4and MgCl 2was 1.5times of NaCl and MgSO 4.So the concentration of NaCl and MgSO 4was 1.5times of Na 2SO 4and MgCl 2with the purpose of gaining the same osmot-ic pressure.Meanwhile,effect of different HS solutions on permeate rate were shown in Fig.5.It demonstrated that the permeate ﬂuxes produced by high salinity solutions did not change very signi ﬁpared with the other solutions,NaCl was the most effective one.On the whole,NaCl was selected as the ﬁnal HS solution thanks to its utmost ef ﬁciency and least dose.4.1.3.Effect of HS concentration on permeate rateIt was understood that a higher feed concentration will induce a larger driving force and a bigger backwash ﬂow rate according to Eq.(1).Some studies [3,14,16]have found that a HS with osmotic pressure of 35–100bar was needed and the corresponding NaCl con-centration should be 43–136kg/m 3[3]during backwash in RO.NaCl so-lutions with concentration in the range of 50–200kg/m 3were studied,0123451.32.63.95.2J / (L /m 2/h )Time / (min)Fig.6.Effect of HS concentration on permeate rate in HS-DOBW cleaning.Table 4Calculation of osmotic pressure for different potential HS solutions.NaCl concentration (kg/m 3)Osmotic pressure/Π(bar)5040.9310081.8611493.32125102.33136111.33150122.79200163.72123451.21.62.02.4J / (L /m 2/h )Time / (min)Fig.5.Effects of different HS solutions on permeate rate.Table 3The osmotic pressure and required dose of the representative four salts.Salt type Osmotic pressure (MPa)Concentration (mol/L)Salt dose (g)NaCl 7.183 1.587.75MgSO 47.183 1.5180Na 2SO 47.1831142MgCl 27.18319530W.Jiang et al./Desalination 359(2015)26–36so as to obtain a feasible osmotic pressure for NF membrane backwash.Osmolality of the corresponding NaCl solutions at different concentra-tions was measured and then was converted to osmotic pressure (Π)with the known density.The results were also shown in Table 4.The effect of HS concentration on permeate rate was shown in Fig.6.In the case presented,the permeate ﬂux of the HS-DOBW with different NaCl feed concentrations was calculated based on the backwash ﬂow rate.As shown,the ﬂux increased with driving force (osmotic pressure)in the range of 50to 150kg/m 3NaCl solution.While the permeate ﬂux was almost the same with NaCl concentration increased when it went beyond 150kg/m 3.So in order to economize the consumption of chem-ical salts and make it eco-friendly,the NaCl concentration of 150kg/m 3was engaged in the subsequent HS-DOBW cleaning processes.4.2.Membrane foulant identi ﬁcationIt was found that at the initial stage of NF process,the deposition of sulfate and carbonate of calcium was the main cause of membrane fouling.At the later fouling stage,besides calcium salts,complex organic foulant functional groups also deposited onto membrane surface and gradually formed a densely packed fouling layer [31].By contrast with organic foulant,the inorganic one was much easier to be cleaned.The membrane foulants of different operation time were identi ﬁed in detail by ATR-FTIR and SEM –EDX,for the sake of understanding the mem-brane fouling process during NF of brackish groundwater.4.2.1.Analysis by ATR-FTIRIn order to identify the compositions of organic and inorganic deposits on the membrane surfaces at different fouling stages,the FTIR spectra of membrane samples including virgin membrane andfouled membrane were compared and shown in Fig.7.HA was the only organic matter in the NF feed water,so it was necessary to know its molecular structural formula (Scheme 1).As shown in Scheme 1,HA was a complex organic matter with many functional groups of hydroxide radical (–OH)and carboxyl (–COOH).The FTIR spectrum for the virgin NF membrane showed characteristics of both polyamide barrier layer and polysulfone support layer [32–34].The broad band centered at 3550cm −1was attributed to the overlapping of bands from the stretching vibrations of O –H.The band at the range of 1680–1750cm −1was attributed to C _O stretching and blending vibra-tions.It was obvious that the transmittance was getting stronger and stronger with operating time,especially after 24h fouling with the band at the ranges of 3200–3650cm −1and 1680–1750cm −1.This was just because the existence of hydroxide radical (–OH)and carboxyl (–COOH),which indicated the deposition of HA on the membrane surface after 24h fouling.So in order to clean the mem-brane more easily,the cleaning time should be ﬁxed on the operating time of 24h.4.2.2.Analysis by SEM –EDXIn order to characterize the changes in morphology at different fouling stages,membrane samples including virgin membrane,and membranes of different time fouling were analyzed by SEM.From Fig.8,it was observed that after 5h and 12h operation,a large amount of white crystal substances appear in the fouling layer,which should be sulfate and carbonate of calcium as con ﬁrmed by ATR-FTIR analyses.After 24h and 36h operation,a densely packed fouling layer which could consist of both organic matters and inorganic salts was observed on the membrane surface.Combined with SEM,EDX was used to analyze the element contents in fouling layers [31,35].The results were shown in Table 5.It was observed that the content of carbon and oxygen was kept changing with fouling time.But the ratio of carbon/oxygen vs.operation time was almost the same as the virgin membrane when the operation time was in the range of 12h.The ratio began to decrease at the fouling time of 24h,which just meant that the HA appeared on the membrane surface after 24h operation,and its weight percent decreased from 5.533to 5.435,while the change was not very obvious.In order to fur-ther con ﬁrm the accurate time of HA appearing on membrane surface,the backwash (with NaCl solution,150kg/m 3)cleaning ef ﬁciencies for membranes with different ﬁltration time had been studied.As shown in Fig.9,at the cleaning time of about 10min,the FRR of membrane with 24,36and 48h ﬁltration reached 99.78%,92.87%and 86.95%,re-spectively.This should be caused by the deposition of organic foulants during NF of brackish groundwater as discussed above,and the osmotic pressure formed by high salinity solution was not suf ﬁcient to remove them.Many studies [2,14,31,36]have suggested that it was easier for the inorganic matters to be cleared from the membrane surface than the organic pollutants.So the critical point of HS-DOBW cleaning was ﬁxed on the operation time of 24h.Then the membrane was easier to be cleaned and its service life could be extended.T r a n s m i t t a n c eWave numbers / (cm -1)parison of the FTIR spectra of NF membrane samples at different fouling stages:(a)virgin membrane,(b)membrane of 5h fouling,(c)membrane of 12h fouling,(d)membrane of 24h fouling and (e)membrane of 120hfouling.Scheme 1.Chemical formula of humic acid (HA).31W.Jiang et al./Desalination 359(2015)26–36。

除盐水站膜分离技术

除盐水站膜分离技术第一部分膜分离技术膜法分离技术一般可分为四类：微滤（MF）、超滤（UF）、纳滤（NF）、反渗透（RO），它们的精度按照以上顺序越来越高。

1、微滤（MF）:能截留0.1~1微米之间的颗粒，微滤膜允许大分子有机物和溶解性固体（无机盐）等通过，但能够阻挡悬浮物、细菌、部分病毒及大尺度的胶体透过，微滤膜两侧的运行压差（有效推动力）一般为0.7bar。

2、超滤膜（UF）：能截留0.002~0.1微米之间的颗粒和杂质和大分子有机物，用于表征超滤膜的切割分子量一般介于1000~100000之间，超滤膜两侧的运行压差一般为1~7bar。

3、纳滤（NF）：截留物质的大小约为0.001微米，截留有机物的分子量大约为200~400左右，对单价引力子盐溶液的去除率低于高价阴离子盐溶液，如氯化钠和氯化钙的脱除率为20~80%，二硫酸镁和硫酸钠的脱除率为90~98%，纳滤一般用于去除地表水的有机物和色度，拖出深井水的硬度和放射性镭，部分去除溶解性盐类，浓缩食品以及药剂分离的有用物质，纳滤两侧运行压差一般为3.5~16bar。

4、反渗透（RO）：是最精密的膜法分离技术，它能够阻挡所有溶解性盐类及分子量大于100的有机物，但允许水分子透过，反渗透膜的脱盐率一般大于98%，反渗透膜两侧的压差一般大于5bar.5、渗透：稀溶液中的溶剂（水分子）自发地透过半透膜（反渗透膜和纳滤膜）进入浓溶液（浓水）侧的溶剂（水分子）流动现象。

6、渗透压：某溶液在自然渗透的过程中，浓溶液侧液面不断升高，稀溶液侧的液面相应减低，指到两侧形成的水柱压力抵消了溶剂的迁移，溶液两端的液面不再发生变化，渗透过程达到平衡点，此时的液柱高差称为该溶液的渗透压。

7、反渗透原理：即在进水（浓溶液）侧施加操作压力以克服自然渗透压，当高于自然渗透压的操作压力施加于浓溶液侧时，水分子自然渗透的流动方向就会逆转，进水（浓溶液）中的水分子部分通过魔成为稀溶液侧的净化产水。

清洁剂在海水淡化膜清洗中的应用优化

清洁剂在海水淡化膜清洗中的应用优化海水淡化是一种重要的技术，用于将海水中的盐分和杂质去除，以生产出可供人类使用的淡水。

在该过程中，膜清洗是海水淡化的关键步骤之一。

清洁剂在膜清洗中的应用对于提高膜的效率和延长膜的使用寿命起着重要作用。

本文将对清洁剂在海水淡化膜清洗中的应用进行优化探究。

首先，选择合适的清洁剂是确保膜清洗效果的关键。

清洁剂的选择应考虑到以下几个方面：清洁效果、膜的材质和结构、环境友好性以及成本效益。

清洁剂应能够有效去除膜表面的污染物，但同时不会对膜材料造成损害。

此外，环境友好性也是选取清洁剂时需考虑的因素，优先选择对环境影响较小的清洁剂。

最后，成本效益也是选择清洁剂时需要考虑的因素，应选择在清洁效果和成本之间取得平衡。

其次，在清洁剂的使用上，应注意适量使用，避免过量使用清洁剂造成的浪费和环境负担。

清洁剂的使用浓度应根据膜表面的污染程度进行调整，以达到最佳的清洗效果。

过量使用清洁剂不仅会浪费资源，而且可能对环境造成污染。

因此，在清洁剂的使用上，需要根据实际情况进行合理的浓度调整。

此外，优化清洁剂的使用时间和清洗频率也是关键。

在实际操作中，根据膜的运行时间和膜的清洗需求，合理安排清洗时间和清洗次数。

清洗时间过长会造成清洁剂的浪费，同时也会影响膜的使用寿命。

而清洗频率过低则会影响膜的清洁效果，适当增加清洗次数可以保持膜的良好工作状态，提高海水淡化的效率。

此外，结合机械清洗和化学清洗相结合也是优化清洁剂应用的一种方法。

机械清洗可以通过物理力量去除膜表面的污染物，而化学清洗则是通过清洁剂溶解和分解污染物。

综合使用机械清洗和化学清洗可以提高清洗效果，并且减少对膜的损伤。

在实际操作中，可以先进行机械清洗，去除大部分污染物，再进行化学清洗，以达到最佳的清洗效果。

最后，定期监测清洗效果也是优化清洁剂应用的重要措施。

通过监测清洗后膜的通量恢复率和溶解性固体残留物含量可以评估清洗效果。

如果清洁剂的应用没有达到预期的效果，可以进行调整，选择更合适的清洁剂或调整清洗方式，以提高清洗效果。

平板膜处理卤水净化处理盐泥的方法

平板膜处理卤水净化处理盐泥的方法我跟你说啊，这平板膜处理卤水净化处理盐泥的事儿，我可是折腾了好长时间，总算找到点门道。

一开始，我真的是瞎摸索。

我就想啊，这平板膜到底咋和盐泥卤水联系起来呢？我先试着直接把含盐泥的卤水往平板膜那弄，就像是把一团乱麻直接塞到一个精致的梳子里面，肯定不行啊。

盐泥把膜孔都给堵住了，根本就过不去，这就是我最开始失败的尝试。

后来，我想到要先处理一下盐泥，不能这么粗放地对待平板膜。

我就先对盐泥进行了初步的沉淀。

这就好像先把沙子和水的混合物静置一下，让沙子先沉到底部一样。

可是这个时候问题又来了，沉淀后的盐泥上层卤水看起来纯净了些，但是还是有一些细小的盐泥颗粒，这些小颗粒跑到平板膜那里，还是会造成堵塞。

然后我就想，这是不是像洗菜一样，得多洗几次才能干净啊。

于是我进行了多次的沉淀，每次都把上层相对干净的卤水慢慢倒出来，重新沉淀。

多经这么几个回合，卤水是干净了不少，再去接触平板膜的时候，情况好了一些，但还是没有达到理想状态。

接着我就想可能得对卤水再有一些预处理。

我对卤水进行了简单的过滤，找了一些比较疏松的材料来简单地拦一下那些可能残留的盐泥小颗粒。

这个方法有点效果，但还是不太对。

有一次我突然意识到，我们可以调整卤水进入平板膜的压力。

我以前只是觉得只要能让卤水过膜就行，没太在意压力。

就好比水龙头开得太大，水溅得到处都是还不好控制，压力太大也让整个处理过程变得很糟糕。

所以我开始小心翼翼地调整压力到一个合适的值，多试了几次之后，发现还真让我找着点感觉了。

不过我还是不太确定这个压力对不同成分的卤水是不是都适用，但至少目前这个方法让我看到了平板膜处理卤水净化盐泥有成功的希望。

我觉着啊，要是谁还想再试试这个方法，不妨就从这些方面入手，一步一步地摸索，肯定也能找到最适合的方法的。

别像我一开始那样，毫无头绪地乱搞，得慢慢总结经验。

这中间肯定还得不断地尝试新东西，比如说找不同的过滤材料来优化预处理，或者是更精准地控制沉淀的时间，我想多研究研究肯定能把这个事情办得更好。

水处理最常用物理化学法：膜法除盐工艺总结，全在这篇文里了

水处理最常用物理化学法：膜法除盐工艺总结，全在这篇文里了欢迎加入环保技术交流圈，在这里你将和万千环保同行一起学习环保技术，得到疑难问题指导和同行交流，最大限度提升环保从业专业技能！本期主题：环保水处理，物理化学法之，反渗透膜工艺，最全攻略介绍！张工培训矩阵号：淼知水圈-最纯粹的环保发烧友大家好，欢迎来到淼知水圈！连续几天给大家分享了有关于活性污泥法指示微生物的小知识，有尾丝虫、膜袋虫和“萌宠”水熊，今天不再分享有关微生物的知识了，咱们换个口味，说一说物理化学法中最常见的一种工艺——膜法水处理。

大家都知道，在水处理中常见的膜有两种：生物膜和物理膜（包括UF、NF、RO等），咱们今天说的膜，并非生物膜，而是RO膜。

希望小伙伴们不要弄混哦~好了，闲话不说，直进主题，下面就让我们来看一看有关于RO膜的那点事儿。

膜法水处理的构成：1、预处理2、膜处理装置3、后处理预处理的作用：1、去除悬浮固体、胶体和各种有机物；2、抑制和控制微溶盐的沉淀；3、调节进水温度和pH；4、杀死和抑制微生物的生长；5、防止铁、锰等金属氧化物和二氧化硅的沉淀。

▲不同粒径的固体颗粒分类以及其对应的去除方式选择▲不同膜的进水要求，注意括号内的数值为最大值淤泥密度指数SDI值：判断反渗透和纳滤进水胶体和颗粒污染程度的最好技术是测量进水淤积指数(SDI值)，有时也称为污染指数(FI值)。

它是设计RO/NF预处理系统之前应该进行测定的重要指标，同时在RO日常操作时也需定时地检测(地表水一般建议每天三次)。

淤积指数的测定方法在美国材料工程协会ASTM标准测试方法D4189-82中已作了规定。

测量仪器：◆47mm直径测试膜盒；◆47mm测试用膜片(孔径0.45μm)；◆1～5bar(10～70psi)压力表；◆调压针型阀▲淤积指数测量仪测量步骤：◆ 将测试膜片小心放在测试膜盒内，用少许水润湿膜片，拧紧“O”形密封圈，将膜盒垂直放置，还应注意膜片有正反面的区别；◆ 调节进水压力至2.1bar(30psi)并立即计量开始过滤500mL水样的时间t0(通过连续不断的调节，使进水压力始终保持不变)；◆ 在进水压力为2.1bar(30psi)下连续过滤15分钟；◆ 15分钟后继续记录过滤同样500mL所需的时间t15，保留滤器上的膜片以便作进一步的分析预处理的方式：◆ 水的混凝与沉淀处理；◆ 水的多介质过滤；◆ 水的活性炭过滤；◆ 水的软化；◆ 其他预处理。

膜法脱盐技术及膜法分离过程

膜法脱盐技术及膜法分离过程反渗透和纳滤过程单独、或与离子交换法、或其它分离过程相结合，可以降低再生剂的费用和废水排放量，也可以用来制备高纯水，在电厂与热法结合时，可以提高设备的利用率和水的利用率。

下图示意性地给出了主要脱盐过程适用于进水含盐量所对应的经济范围，即离子交换法、电渗析法、反渗透法及蒸馏法四种脱盐方法的最典型的操作范围。

目前常规的过滤过程可以按照脱除颗粒的大小进行分类，传统的悬浮物的过滤是通过水流垂直流过过滤介质来实现的，全部的水量完全通过过滤介质，全部变成出水流出系统，类似的过滤过程包括：滤芯式过滤、袋式过滤、砂滤和多介质过滤。

这种大颗粒过滤形式仅仅对粒径大于1 微米的不溶性固体颗粒有效。

为了除去更小的颗粒和可溶性盐类，必须使用错流式的膜过滤，错流式膜过滤对与膜表面平行的待处理流体施加压力，其中部分流体就透过了膜表面，流体中的颗粒等被排除在浓水中，由于流体连续地流过膜表面，被排除的颗粒不会在膜表面上累积，而是被浓水从膜面上带走了，因此一股流体就变成两股流体，即透过液和浓缩液。

膜法液体分离技术一般可分为四类：微滤(MF)、超滤(UF)、纳滤(NF)和反渗透(RO)，它们的过滤精度按照以上顺序越来越高。

微滤(MF)微滤能截留0.1~1 微米之间的颗粒，微滤膜允许大分子有机物和溶解性固体（无机盐）等通过，但能阻挡住悬浮物、细菌、部分病毒及大尺度的胶体的透过，微滤膜两侧的运行压差（有效推动力）一般为0.7bar。

超滤(UF)超滤能截留0.002~0.1 微米之间的颗粒和杂质，超滤膜允许小分子物质和溶解性固体（无机盐）等通过，但将有效阻挡住胶体、蛋白质、微生物和大分子有机物，用于表征超滤膜的切割分子量一般介于1,000~100,000 之间，超滤膜两侧的运行压差一般为1~7bar。

纳滤是一种特殊而又很有前途的分离膜品种，它因能截留物质的大小约为1 纳米（0.001 微米）而得名，纳滤的操作区间介于超滤和反渗透之间，它截留有机物的分子量大约为200~400 左右，截留溶解性盐的能力为20~98%之间，对单价阴离子盐溶液的脱除率低于高价阴离子盐溶液，如氯化钠及氯化钙的脱除率为20~80%，而硫酸镁及硫酸钠的脱除率为90~98%。

NACE膜技术处理高盐废水的实验研究的开题报告

NACE膜技术处理高盐废水的实验研究的开题报告一、选题背景：随着工业化进程的加快，废水排放密度不断加大，这使得废水处理成为一个严峻的问题。

其中，高盐废水处理是其中一项重要的难题，因为高盐废水中的盐类浓度过高，直接排放会对生态环境和人类健康造成严重威胁。

因此，处理高盐废水的技术一直是废水处理领域中的难点和热点。

NACE膜技术是一种新型的高效膜处理技术，它利用特殊的膜材料进行操作，能够有效地去除高盐废水中的盐分和其它污染物，提高废水处理的效果。

因此，本研究选取了NACE膜技术来处理高盐废水，为地下水资源的保护和环境安全做出一定的贡献。

二、研究目的：本研究的目的是探究NACE膜技术对高盐废水的处理效果，通过构建实验模型，研究NACE膜技术处理高盐废水的适用性、理论原理和操作方法，从而为生产应用提供参考和借鉴。

三、研究方法：本研究采用实验室模拟的方法，通过构建陶瓷膜、正渗透膜和反渗透膜的NACE处理系统，对不同盐浓度的模拟高盐废水进行处理。

在此基础上，配合SEM、TEM、FTIR等分析技术，对NACE膜的形态、结构、功能等进行全面分析。

四、研究内容：1. 概述NACE膜的基本原理2. 构建NACE膜处理高盐废水的实验系统3. 在实验系统中对不同盐浓度的废水进行处理，对去除率进行测定，并分析处理机理4. 利用SEM、TEM、FTIR等技术对NACE膜的形态、结构、功能等进行分析五、研究意义：现在高盐废水的处理刻不容缓，选取NACE膜技术将有助于解决高盐废水问题，同时也将有助于提高环境保护、水资源利用效率和废水综合利用率等方面做出新的贡献。

此外，本研究将为进一步深入研究和应用NACE膜技术提供技术和理论基础。

科技成果——高效低温膜蒸馏高盐水处理技术

科技成果——高效低温膜蒸馏高盐水处理技术成果简介
膜蒸馏技术是一种采用疏水性微孔膜的新型膜脱盐技术，该技术常压脱盐，操作运行方便；可处理高浓度盐溶液，产水率远远高于其它膜分离技术。

膜蒸馏脱盐技术分离效率高、环境友好，且便于与其它净化处理过程耦合与集成，在水的淡化、化学物质回收、高盐废水处理及回用等领域具有巨大应用前景。

技术特点
（1）常压进行，设备构造简单，操作运行方便；
（2）仅有水蒸汽能透过膜孔，产水水质纯净；
（3）可处理高浓度盐溶液，产水率远高于其它脱盐技术；
（4）可利用工业废/余热以及太阳能、地热等绿色热源。

技术成熟度成熟应用
市场前景
该技术在高盐废水回用处理，实现“零”排放，减少环境污染负荷，大幅度提高水资源利用率方面展现了广阔的产业化和工业化应用发展前景，尤其该技术的产业化及工业化应用可有效解决制约我国水环境污染治理、节能减排、区域社会经济可持续发展的高盐废水达标排放问题。

应用情况
目前该项技术已经在国内的多家企业，对不同的高浓度工业废水进行了示范应用，如内蒙达拉特旗火电厂反渗透浓盐水、山东铝业公
司氧化铝生产过程的碱性浓水、甘肃金川电解镍生产过程的高浓度硫酸钠废水、中石化环氧氯丙烷生产过程的高浓度氯化钙废水、山东染料厂的高盐度高色度废水、吉林糠醛厂的高浓缩酸性糠醛废水、北京大兴电子荧光屏酸性高磷废水、印钞厂酸性电镀废水等。

膜技术用于硬水脱盐

・
６２・
矿产综合利用
２０１６年
表２氢氧化钠用量脱除钙镁效果影响
Ｔａｂｌｅ２Ｅｆｆｅｃｔｏｆｓｏｄｉｕｍｈｙｄｒｏｘｉｄｅｄｏｓａｇｅｏｎｒｅｍｏｖｉｎｇｏｆｃａｌｃｉｕｍａｎｄｍａｇｎｅｓｉｕｍ
成本在２０— ３０ｔ。在目前金价较低的情况下，一
般企业难以承受如此高的用水成本。
收稿日期：２０１５ — １２ — ０８
作者简介：季常青（１９８１一），男，工程师，主要研究方向为湿法冶金、环保、资源综合利用研究。
本文通过合理的膜芯选型试验与分离工艺研
究，考察采用膜处理工艺分离除镁的经济、技术可行性，以最大程度的降低原水中钙、镁离子的浓度，减少氰化调碱过程中，石灰或片碱的投加量，以达到降低氰化成本的目的。
３．２膜运行压力与水通量关系
ＺＪ．ＮＫ膜芯对该高盐原水通量与压力之间的关
系见图１。
Ｚ
当面
嘲｛Ｌ鹫
表３氢氧化钠＋碳酸钠用量对除钙镁效果影响
Ｔａｂｌｅ３Ｅｆｆｅｃｔｏｆｄｏｓａｇｅｏｆｓｏｄｉｕｍｈｙｄｒｏｘｉｄｅ＋ｓｏｄｉｕｍ

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井下回注、制建筑用材（如制砖、水泥、石膏、涂料和无机纤维板等）和有用成分的分离提取（如碳酸钙、氢
氧化镁、氧化镁、七水硫酸镁、硫酸钡和氯化钙等）．们曾采用盐泥制备吸附材料和高分子填充料等我，
对盐泥进行处理取得了较好的结果Ｊ但是盐泥中含有大量的ＮＣ，占总质量的１％一１％，量．ａ１约１７大
重点考察，对膜孔径、过程参数对处理效果的影响进行系统研究．结果表明，Ａ在Ｐ＝０２ａ．ＭＰ，４
＝０５６ｍｓ质量浓度为１，．７／，％Ｔ＝３５±３Ｃ下，用孔径为０２ｔｎ的ａＡ２３陶瓷膜清洗盐￣采．ａ．ｌ０
收稿日期：０００．２２１．２２
基金项目：江苏省高校自然科学研究重大项目（９５０Ｏ）０Ａ３ｏ１作者简介：吕静品（９４）１７一，女，江苏沛县人，助理研究员，硕士研究生，研究方向为新型环境材料及膜分离技术
第２期过滤）．
吕静品等：盐泥除盐的膜清洗技术研究
Ｏ引言
盐泥是氯碱、盐行业卤水净化工艺中产生的废渣，制含有碳酸钙、氧化镁、氢氯化钠以及铁、钡盐等，由于产出量大（通常每生产一吨氢氧化钠排出约０３．的盐泥）成分复杂，．～０９ｍ，直接排放带来环境污染，如何对其进行综合利用是困扰行业的一个难题＿］目前已有报道的盐泥综合利用方法主要有盐泥１．卫
泥，有较好的除盐效果．具污染膜在０１ｏＬＨＯ．ｍｌＮ溶液中浸泡煮沸约３ｉ，０／０ｍｎ然后水冲洗，膜通量基本恢复．
关键词：陶瓷膜；泥；除盐盐中图分类号：７Ｘ９文献ቤተ መጻሕፍቲ ባይዱ 识码：Ａ文章编号：６１８６２１）２０３．４１７．７（０００ —１４０６
Ａｐ．２０ｒ０１
盐泥除盐的膜清洗技术研究
吕静品，赵宜江
（．１南京工业大学化学化工学院，江苏南京２００；１０９２３０）２３ｏ２淮阴师范学院江苏省低维材料化学重点建设实验室，．江苏淮安
摘
要：针对盐泥悬浮颗粒体系，用国产无机陶瓷膜，采对盐泥除盐膜清洗工艺的可行性进行
便，膜通量高，再生能力强等优异的材料性能，致使它在液体分离领域应用日益广泛，它独特的错流过滤
方式，异的物理、学性能和机械强度，优化为超细粉体的生产提供了新型的分离与洗涤技术．
本文针对盐泥悬浮液这一体系，采用无机陶瓷微滤膜，对微滤处理盐泥的技术可行性进行考察，重
１５３
１２膜过滤装置．
实验装置如图１所示．液槽中的浆料依靠重力作用，液槽流至离心泵，从由离心泵提供运行总动力，使浆料在整个系统中循环．过出水阀门的调节，以给予膜管一定的压力，通可浆料在压力作用下，部分大回流至液槽中，而少部分则经膜管渗透从组件侧面出口流出．在渗透的过程中，而盐泥被截留在膜管表面．速及过滤压差由各阀门来调节控制．流
点对膜孔径、程参数等进行系统研究，过为无机陶瓷微滤膜技术应用于盐泥除盐工艺中提供数据基础．
１实验部分
１１材料与试剂．
单管陶瓷膜由南京工业大学膜科学技术研究所提供，材料为ａ０，径分别为Ｏ２０５和膜一１孔．，．
０８．膜面积为００８，．／ｔｍ，．３膜管内径（）７ｎ膜管长度为１ｃ，０２ｍＩ为ｎ，Ｄｉ５ｍ盐泥由江苏安邦电化有限公司
氯碱厂提供，Ｎ３Ａ）自上海久亿化学试剂有限公司，ＨＯ（Ｒ购去离子水为实验室自制（经过Ｏ２／．ａｎ的滤芯
ＮＣ的存在势必会影响其开发利用和性能．ａ１因此，在使用之前需要将其中的 №ａ清洗掉．如果直接用水去清洗，会浪费大量的水资源，且不容易清洗干净．将而近年来发展的无机陶瓷膜因具有化学稳定性好（耐酸、耐碱、耐有机溶剂、耐高温、耐微生物侵蚀）机械性能好、径分布窄等突出优点，且清洗方，孔并
第９卷第２期
２１００年４月
淮阴师范学院学报（自然科学）
ＪＵＮＬＯＵＩＩＥＣＥＳＣＬＥＥ（ａｒｃｎｅＯＲＡＦＨＡＹＮＴＡＨＲＯＬＧＮｔａＳｉｃ）ｕｌｅ
Ｖ１９Ｎ．０．０２
１一液槽，一离心泵，一转子流量计，一温度计，一压力表（２３４５表压）－膜组件，一滤液槽，一电子天平，９，６７８一计算机．
图１膜过滤装置流程图
１３膜清洗方法．实验结束后对陶瓷膜进行必要的清洗，清洗方法为：先在０１ｏＬＩ０溶液中浸泡、沸约．０ｍｌＮ３／－Ｉ煮