陶氏4英寸超滤膜的运行方式

陶瓷超滤膜工作原理2019.10.26陶氏超滤膜可去除溶液中的大分子、胶体、蛋白质、微粒等，具有使用压力低、产水量大、便于操作的特点。

通过测试中空纤维超滤膜装置深度净化制酒原水的处理效果，证明超滤膜净水装置能有效地消除水在管网中的二次污染，进一步提高水质。

陶氏超滤膜工作原理是在常温下以一定的压力和流量，利用不对称微孔结构和半透膜介质，以膜两侧的压差为动力的一种新型膜分离技术。

超滤膜特有的0.01—0.1um孔径可有效阻留细菌，大多数病毒，胶体以及淤泥。

从而达到分离、分级、纯化、浓缩目的。

超滤膜特征1、超滤膜具有超小的孔径，能够高效的去除颗粒物，细菌，大部分病毒和胶体，并结合着均匀的膜空和外压式结构，可以确保组件在多种复杂的水质条件下，仍然可以保证高效稳定的运行。

当压力增大时，可以通过反冲洗和气洗的方式进行清洗和维护，延长膜的寿命。

2、超滤膜的孔径超小，确保高效过滤，水质达到用水标准。

除菌率可达到99.99%。

3、陶氏超滤膜材质超强，可以延长使用寿命。

独特的双层结构膜丝，抗化学性较强，足以抵抗强酸强碱的侵蚀，机械的强度高，不易断裂。

4、陶氏陶瓷超滤膜结构抗压力强，能够保证持续低能耗稳定运行。

其外压结构，过滤面积更大，进水要求低，适合的原水范围更广阔。

外压的膜丝不易堵塞，清洗频率大幅降低、节约能耗，节省成本。

陶瓷超滤膜应用领域1、陶瓷超滤膜作用：陶氏陶瓷超滤膜SFP 2660对细菌和大多数病毒的去除率可达到99.9%。

过滤精度高，保证饮水安全。

2、RO预处理：超滤具有高效的固体分离和去除截留病原体等特点，还能够适应海水复杂的变化，因此被广泛应用于海水淡化(RO)预处理，为RO系统提供高质量的产水，保证系统的稳定运行。

3、废水回用：陶氏陶瓷超滤膜低能耗，高分离效率的特点，既能对废水进行有效的净化，又能回用其中的有用物质，同时还可节省能源。

使超滤成为废水回用和废水资源化的主要应用技术。

陶氏陶瓷超滤膜利用超小孔径的双皮层结构H—PVDF膜，高效去除颗粒物，细菌，大部分病毒和胶体。

Dow Water & Process SolutionsIntegraPac™ Module andSkid Product ManualVersion 1May 2013This manual is confidential. It is the property of Dow Water & Process Solutions. The contents may not be reproduced, transferred or released to any third party without the written permission of Dow Water & Process Solutions.Table of Contents1. Introduction (1)2. Description of DOW™IntegraPac™ Ultrafiltration Module (2)2.1 IntegraPac™ Module and Skid Features (2)2.2 IntegraPac™ Module and Skid Specifications (5)2.3 IntegraPac™ Module and Skid Installation (8)3. Shipping and Storage (9)4. DOW IntegraPac™ Ultrafiltration Process Description (11)4.1 Process Operations (11)4.2 Pretreatment (16)4.3 Cleaning (17)Summary of Information (17)4.4 Fouling (17)5. Operating Information (18)5.1 Start Up (18)Pre-start checks (18)Start Up (18)Module rinsing (19)5.2 Integrity Testing procedures (19)Pressure hold/decay (19)Visual inspection test (19)5.3 Shut Down (20)Manual shut down (20)Equipment shut down during automatic operation (20)5.4 Operating and Cleaning Logs (20)ReferencesFigure 1: Material Size and Membrane Process Guide (1)Figure 2: Wall Cross Section of the Hollow Fiber (2)Figure 3: IntegraPac TM Module Photograph (3)Figure 4: IntegraPac™ Skid Components (4)Figure 5: Module Reference for Dimensions (5)Figure 6: IntegraPac™ Skid Reference for Dimensions (7)Figure 7: Installation™ Drawing of Module (8)Figure 8: Pallet of IntegraPac™ Modules for Shipping (9)Figure 9: Filtration Step for DOW UF Modules (12)Figure 10: Air Scour Step for DOW UF Modules (12)Figure 11: Air Scour Drain for DOW UF Modules (13)Figure 12: Top Backwash Step for DOW UF Modules (13)Figure 13: Bottom Backwash Step for DOW UF Modules (14)Figure 14: Forward Flush Step for DOW UF Modules (14)Figure 15: Chemically Enhanced Backwash "Top" Step for DOW UF Modules (15)Figure 16: Chemically Enhanced Backwash "Bottom" step for DOW UF Modules (15)Figure 17: Clean in Place Cleaning Step for DOW UF Modules (16)Figure 18: Pressure Hold Test Schematic (20)TablesTable 1: IntegraPac TM Module Connections (5)Table 2: IntegraPac™ Module Dimensions and Specifications (5)Table 3: IntegraPac™ IP-51 and IP-77 Skid Details (6)Table 4: Glycerin addition for Freezing Point Depression (11)Table 5: DOW Ultrafiltration IntegraPac™ Modules and Skids Operating Conditions (11)Table 6: Qualified Feed Water Quality Parameters (17)Table 7: Summary of Cleaning Processes (17)DOW™ IntegraPac TM Ultrafiltration Module and Skid Product Manual1. IntroductionUltrafiltration (UF) involves pressure-driven separation of materials from a feed solution. The technology achieves separation through sieving and is used to remove particulate and microbial contaminants, but does not remove ions or molecules of low molecular weight. The process typically operates with a feed pressure of 4 to 100 psig (0.28 to 6.9 bar). UF plants are automated and have low operational labor requirements. Depending on the feed water quality, these systems can require frequent cleaning. UF membranes generally may have a service life of five years or longer, depending on system operations. UF technology is commercially available in tubular, hollow-fiber, plate and frame, flat sheet, and spiral wound configurations.UF membranes reject solutes ranging in size from 0.005 microns and larger. Figure 1 provides a guide to the relationship between common material sizes, separation processes, and pore size measurements. The UF membrane process separates molecules in solution on the basis of size. The pore size and molecular weight cut-off (MWCO) are often used to characterize a membrane. The pore size is the nominal diameter of the openings or micropores in the membrane expressed in micron (micron meters µm). The MWCO is the molecular mass or weight of a solute that rejects greater than 90 percent. The unit of measurement for MWCO is the Dalton (D).Different membrane materials with the same nominal MWCO may have differing solute rejection. Pore size distribution and uniformity rather than the chemical nature of the membrane material may cause this effect. Because factors other than pore size or MWCO affect the performance of membranes, challenge studies are used to demonstrate membrane performance and benchmark different membranes.Figure 1: Material Size and Membrane Process GuideThe DOW Ultrafiltration hollow fiber membrane shown in Figure 2 is 1.3 mm outside diameter and 0.7 mm inside diameter and is made from PVDF polymer. The fibers are strong because of a combination of the polymer type,The 0.03 μm nominal pore size combines high filtration performance and high flux. The smaller pore size provides stabile long term filtration performance compared to microfiltration hollow fiber membranes. Dow has taken its Ultrafiltration technology to a new product format, referred to as IntegraPac TM modules and skids. This range includes interconnecting end caps that reduce skid capital costs and engineering design efforts.2. Description of DOW ™ Ultrafiltration IntegraPac ™ Module2.1 IntegraPac TM Module FeaturesThe DOW Ultrafiltration IntegraPac TM modules are made from high strength, hollow fiber membranes and are engineered to reduce design and fabrication requirements with features and benefits including:∙ 0.03 µm pore size for removal of bacteria, viruses, and particulates, a 6 log removal of bacteria, a 2.5 log removal on viruses and a <2.5 SDI guarantee with proper operation∙ PVDF fibers which offer strength, chemical and fouling resistance which allows for extended membrane life and consistent long term performance∙ Outside-In flow configuration which allows higher TSS feed waters, while maintaining reliable system performance and producing high quality filtrateInnovative end-cap design enables direct coupling of modules reducing the need for piping and manifolds. The outside-in flow configuration allows the use of highly effective air scour cleaning which enhances particle removal and improves recovery. A dead-end flow format achieves higher recovery and energy savings. The module housing design eliminates the need for separate pressure vessels while the vertical orientation allows easy removal of air from cleaning and integrity testing processes.Figure 2: Wall Cross Section of the Hollow FiberThe IntegraPac TM module is shown in Figure 3. There are six connections on each module. The top end cap includes 4”DN 100 concentrate ports and an 1½” DN 40 union for the. The bottom end cap includes 4” DN 100 feed ports and a 3/8” air inlet connection on the side allowing for easy access. Included with the module are the couplers, air fitting, and transparent filtrate elbow. The IntegraPac TM skid offering is shown in Figure 4.Selective ActiveArea0.3 mm Wall ThicknessFeed Outside to InFiltrateSubstructureFigure 3: IntegraPac TM ModuleFiltrateConcentrateFeedAirConnectionF i g u r e 4: I n t e g r a P a c ™ S k i d C o m p o n e n t sFeed flow enters and is distributed into the modules through the side feed ports located on the bottom end cap. Feed flow enters the module on the outside of the fiber. The air connection is located on the side of the bottom end cap and is used for air scouring and integrity testing. The concentrate (discharge of waste flows from the outside of fiber) and filtrate ports (inside of fiber) are located on the top cap.Table 1: IntegraPac TM Module and Skid ConnectionsModule DN 100 (4 inch) Coupler DN 40 (1.5 inch) Threaded Union 3/8 inch Threaded (G3/8”) Skid DN 100 (4 inch) FlangeDN 150 (6 inch) Flange DN 65 (2.5inch) FlangeTable 1 shows the type and size of the connections for the IntegraPac ™ modules. 2.2 I NTEGRA P AC ™ M ODULE AND S KID S PECIFICATIONSTable 2 shows dimensions and specifications for the IntegraPac TM modules as depicted in Figure 5. Table 3 includes the dimensions and specifications for the IntegraPac TM skids as depicted in Figure 6. Note that manufacturing and thermal expansion tolerances are not included in the dimensions below. Refer to the installation drawings for this information.Table 2: IntegraPac ™ Module Dimensions and SpecificationsFigure 5: IntegraPac ™ IP 51 and IP 77 Module Reference DrawingT a b l e 3: I n t e g r a P a c I P -51 a n d I P -77 S k i d D e t a i l si g u r e 6: I n t e g r a P a c ™ S k i d R e f e r e n c e f o r D i m e n s i o n sx a m p l e : 2x 7 t e g r a P a c I P -51-14 A r r a n g e m e n t2.3 InstallationDetailed installation instructions are provided for the Dow IntegraPac TM skids upon request. Figure 7 provides the installation details for DOW™ IntegraPac TM modules.Figure 7: Installation™ Drawing for IntegraPac™ IP 51 and IP 77 Modules3. Shipping and StorageTo control bacterial growth and prevent damage caused by fibers drying out, the DOW TM Ultrafiltration IntegraPac TM modules are wetted and stored in a non-hazardous standard storage solution containing pH buffered food-grade 1% wt. sodium metabisulfite (SMBS). At the end of the manufacturing process, storage solution is automatically injected into the modules and all inlet and outlet ports are sealed using plastic discs, couplings, and threaded plugs. If the modules will be exposed to low temperatures, glycerin can be added to the storage solution to prevent freezing. The modules are sealed in a plastic bag prior to boxing. Depending on the total number of modules and method of shipping, the modules are either shipped on pallets as shown in Figure 8 below or in crates. Skid components (underframe, air scour piping, filtrate piping) are shipped in a separate boxes or crates.As part of the quality assurance program, all DOW™ IntegraPac™ modules are tested for integrity and performance (“wet tested”) at the factory, prior to packaging and s hipment.Storage solution is automatically delivered into the module housings prior to sealing of the module ports. The target volume of storage solution used for each module is 4L (1 gal) for IP-51; and 6L (1.6 gal) for IP-77. After adding storage solution and sealing the openings, the modules are enclosed in plastic bags prior to boxing for dust protection. The storage solution volume and complete sealing of the module ports and openings help ensure a stable solution environment during transportation and storage of new modules.The bagged modules are stored in cardboard boxes, with one module per box. Saddle-shaped cushion inserts are located at both ends of the box and along the module to support and protect the modules from damage during shipping and handling. Depending on the total number of modules and required shipping method, the boxed modules are either palleted or crated for transportation. Other skid parts are placed in crates and shipped with the modules.Mechanical damage to module housing, membrane, and connections may result if the module, boxed module, pallet or crate is dropped, and otherwise mishandled. The modules should be handled with care, with particular attention during transportation.Figure 8: Pallet of IntegraPac™ Modules for ShippingStorage of New IntegraPac™ Modules:Modules are recommended to be shipped and stored in their original packaging separate from the system racks, and loaded into the system just prior to start-up. There may be cases where the customer prefers to pre-install the modules on the system racks; for example, to allow factory acceptance testing of packaged or mobile systems prior to shipping, or work scheduling at site to eliminate the separate step for module loading.These guidelines should be followed for storage of new DOW TM IntegraPac™ modules:∙Keep modules in original factory packaging.∙To minimize the potential for leakage of storage solution, modules should be stored in horizontal position.∙To prevent collapse of the boxed modules, limit vertical stacking to four layers of modules.∙Store inside a cool and dry building or warehouse, away from sources of heat, ignition, and direct sunlight. An ambient temperature of 20°C (68 ºF) to 35°C (95 ºF) is recommended for ideal storageconditions.∙Temperature limits for modules during shipping and storage is 1ºC (33.8 ºF) to 40ºC (104 ºF). Modules must be protected from freezing or excessive heat during shipping and storage. In order to avoidabrupt variations in temperature; equalization should be allowed to occur at a maximum temperaturedifferential of +/- 1°C (1.8 ºF) per minute. If freezing conditions are anticipated during the customer’sshipping and storage of modules, please notify DW&PS at the time of order placement. Glycerine may be added to the storage solution at the factory prior to shipping to allow for shipment and storage atfreezing conditions.∙Sealed modules may be stored up to 1 year from date of manufacture, at the recommended storage conditions described above and in the original packaging.Storage of modules installed on a skid:Modules (hollow fibers) installed during assembly of a skid should not be allowed to dry out. Dry membrane fibers will irreversibly lose flux. Blank or “dummy” modules are available to accurat ely build and assemble a skid. Consult the manufacturer regarding modules installed on a skid and not planned for operations within 7 days. UF systems are designed to run continuously and membrane systems perform better when operated continuously. However, in reality UF systems will start-up and shutdown on some frequency. Before the UF system shuts down, the system must be cleaned using air-scour and filtrate water backwash to prevent bio-growth in the UF system.The water used for backwash before shutdown should not contain chemicals. Any feed water and backwash chemical dosing used should be stopped before the last cleaning and shutdown. After cleaning, all valves on the UF system should be closed to seal the system.To avoid leakage in the module housing end caps and clamps, the backpressure in the modules should be controlled when the UF system shuts down, especially in case of non-scheduled shutdowns, e.g. power failure or emergency shutdowns.When the system is down for greater than 96 hours, note the following:∙The module should not dry out. Dry membrane fibers will irreversibly lose flux at any time.∙The system should be adequately protected against bio-growth, flushed for duration of 30 to 60 minutes once a day, or operated every 24 hours. If flushing with feed water, the quality should be <10 NTU or<10 mg/L TSS.∙The system should be protected against temperature extremes. The UF system can be shut down for96 hours without adding storage solution or taking additional precautions for microbiological fouling.Storage of modules off skid:For cases of long-term shutdown where the modules will remain out- of-service for an extensive period of time (weeks to months), the modules can be removed from the skid and stored to eliminate maintenance operations. If the module has been in service, a Chemically Enhanced Backwash (CEB) or Clean In Place (CIP), followed by an air scour and backwash (without chemicals) should be conducted before decommissioning the equipment. Add 4 and 6 liters of storage solution into the feed port of an IP-51 and IP-77 IntegraPac™ module respectively. The module should be kept in the horizontal position at the time of filling, with the remaining ports and openings sealed. Once the target volume of storage solution is added into the module, seal the feed ports and store the modules in the horizontal position. Modules should be placed in a plastic bag for protection and keeping the modules clean.If the modules will be exposed to freezing conditions glycerin should be added to the storage solution. It is recommended that food grade glycerin be added to the storage solution at the target strength detailed in Table 5. Enough solution should be added to wet the hollow fibers. Completely filling the modules with solution is not required. Modules prepared as described can be stored for 90 days. Consult the manufacturer for storage durations greater than 90 days.Warranty return of modules:Review the project warranty information for authorization instructions before shipping modules for return. To prepare a module for shipment drain the module, plug or seal the openings/ports, and secure the module on a pallet or in a crate.Table 4: Glycerin addition for Freezing Point Depression4. DOW Ultrafiltration IntegraPac™ Process Description4.1 Process OperationsThe basic operating conditions for the DOW Ultrafiltration IntegraPac™ modules and Skids are shown in Table 6 below. Operating parameters for the cleaning steps are provided in the section that describes cleaning.Figure 9: Filtration Step for DOW UF IntegraPac Modules and SkidsNormal operation refers to the routine operating sequence of a system using the DOW TM Ultrafiltration IntegraPac™ module and includes the operating and backwash steps. Consult Dow for commissioning procedures. At initial start up the modules are flushed using a “forward flush” to remove any residual chemicals or trapped air from the module. The flush occurs on the outside of the fibers and does not filter the feed water to produce filtrate. After the forward flush is discontinued the modules can be placed in the operating mode. An operating cycle ranges from 20 to 90 minutes in duration. While operating, 100% of the feed water is converted to filtrate. This is also referred to as dead end filtration. As contaminants are removed and deposited on the hollow fiber membrane surface during the operating step the transmembrane pressure will rise. At the end of the preset operating cycle time, a backwash sequence commences.Figure 10: Air Scour Step for DOW UF IntegraPac™ Modules and SkidsThe backwash mode occurs automatically usually on a preset time basis. The steps include an air scour, draining by gravity, backwash through the top outlet, backwash through the bottom outlet, and a forward flush. The air scour step is used to loosen particulates deposited on the outside of the membrane surface. Air is introduced on the outside of the fibers using only the hold up water volume of the module. Displaced feedflow/concentrate is allowed to discharge through the top of the module for disposal. After 20 to 30 seconds of continuous or intermittent air scour the module is drained by gravity.Figure 11: Air Scour Gravity Drain Step for DOW UF IntegraPac™ Modules and SkidsAfter the gravity draining step, the first backwash step is performed. Filtrate flow is reversed from the inside of the fiber to the outside and backwash flow is removed from the module housing through the top outlet. Figure 12: Top Backwash Step for DOW UF IntegraPac™ Modules and SkidsThe second backwash step is performed to remove backwash water through the bottom outlet. Filtrate continues to flow from the inside of the fiber to the outside and backwash flow is removed from the module housing through the bottom outlet of the module, ensuring the entire length of fibers have been cleaned. The backwash steps can be repeated numerous times depending on the degree of fouling. After backwash is complete, a forward flush is performed to remove any remaining large particulates and air trapped on the outside of the fibers. After a backwash, the modules are returned to the normal operating mode.Figure 13: Bottom Backwash Step for DOW UF IntegraPac™ Modules and SkidsCEB operation refers to a chemically enhanced backwash. The frequency of a CEB is dependent on the feed water quality. On high quality feed waters a CEB may not be required. The CEB process is programmed to occur automatically but the frequency can be field adjusted after gaining site specific operating experience. The CEB is performed using UF filtrate and either an acid, or alkali chemical. The alkali solution can be a combination of oxidant and caustic to more efficiently clean contaminants from the membrane surface. Selection of chemicals is made according the DOW Ultrafiltration applications guidelines and understanding of the foulants in the feed water.Figure 14: Forward Flush Step for DOW UF IntegraPac™ Modules and SkidsThe CEB is performed using the steps of a normal backwash except during a CEB, chemical is dosed into the backwash water and a soak step is added after the second backwash step. In addition the CEB can be performed at reduced flow, usually 50% of the backwash flux.Figure 15: Chemically Enhanced Backwash "Top" Step for DOW UF IntegraPac™ Modules and SkidsThe soak is performed for 5 to 20 minutes and allows time for the chemical to react with contaminants that have attached to the membrane surface or penetrated the fiber wall. Intermittent air scour can be applied during the soak step. After the soak a routine backwash including air scour, gravity drain, top and bottom backwash, and forward flush is performed to remove any remaining particulates and purge residual chemicals. After a CEB and at the start of the operating step, the initial filtrate produced may be sent to waste to remove residual chemicals. This step is dependent on the system piping and valve design and the downstream requirements for the filtrate. Figure 16: Chemically Enhanced Backwash "Bottom" step for DOW UF IntegraPac™ Modules and SkidsCIPA clean in place (CIP) is an offline operation that includes backwashes and chemical recirculation and soaking to clean the hollow fibers. The CIP is an on demand operation. It can be an automated process but is most often conducted manually. The frequency of a CIP is dependent on the feed water quality and routine fouling control strategy but can range from 1 to 6 months. Prior to a CIP the routine backwash steps including air scour, draining, backwash through the top outlet, and backwash through the bottom outlet are performed. Thebackwash steps can be repeated multiple times to remove contaminants or foulants not requiring chemical removal. After completing the backwash steps, the module is drained by gravity to remove excess water and prevent dilution of the CIP chemical solution. The CIP chemical solutions are recirculated through the modules on the outside of the hollow fibers for 30 minutes through a chemical mixing and solution tank. A portion of the recycle stream can be passed through the hollow fibers and recycled to the chemical cleaning tank. A cartridge filter is used to remove particulates from the CIP solution during recycle. Note that the CIP solution can be heated to 40ºC to improve effectiveness for removing contaminants from the hollow fibers. The CIP solution pH can be measured during the cleaning process and refreshed with chemicals to maintain the target pH and effectiveness of the solution. A soak is performed after the initial recycle step for 60 minutes or longer depending on the degree of fouling that has occurred. After the soak step, CIP chemicals are again recycled through the modules on the outside of the hollow fibers for 30 minutes. Air scour for short durations can be performed during the soak and recycle steps to prevent channeling of the solution through the module. When the recycle is completed an air scour is performed and then the module is drained to remove the concentrated chemical solution. The top and bottom backwash and the forward flush steps are also performed to remove any remaining particulates on the outside of the fibers. After a CIP and at the start of the operating step, filtrate may be sent to waste to remove residual chemicals held in the fiber or module. The CIP steps described above are for a single alkali or acid chemical solution. If both an acid and alkali cleaning are required, the CIP steps would be repeated for each chemical solution.Figure 17: Clean in Place Cleaning Step for DOW UF IntegraPac™ Modules and Skids4.2 PretreatmentDOW Ultrafiltration IntegraPac™ Modules and Skids designs are based on qualified feed water conditions as shown in Table 7. The UF IntegraPac™ Modules and Skids can tolerate period excursions in feed water quality as shown as the maximum allowable in Table 7. If the feed water quality is outside of the design basis range Dow should be consulted to determine if a pilot study is needed to confirm performance or if a pretreatment step is necessary. Also, if the membrane filtration system is designed and installed to the conditions below but the feed water quality is not maintained, please consult Dow Water & Process Solutions.2 Residual in filtrateDepending on application, a safety screen of 100 - 300 microns is recommended on the feed before the UF IntegraPac™ Modules and Skids. In seawater applications, a strainer size of 100 – 150 microns is recommended to prevent the growth of barnacles and mussel larvae in upstream, process pipework and tanks. A variety of technologies can be used such as self-cleaning screens and filters and bag, cartridge, or disc filters. Depending on the type of water or range of feed water parameters other pretreatment processes such as oxidation, coagulation, clarification and media filtration may also be needed.4.3 CleaningSummary of InformationThe process operating parameters for the cleaning steps are provided in Table 8 below.4.4 FoulingThere are four types of fouling common to UF operations including particulate, biological, inorganic, and organic.Particulate fouling is caused by suspended solids, colloids, and turbidity. To reduce particulates in UF feed water coagulation, sedimentation, clarification, and filtration are often used. The common cleaning method for particulate fouling is air scour and backwash.Biological fouling is caused by the growth of microorganisms. Using in-line chemical feed of chlorine or biocide or eliminating nutrients by using PAC, GAC, or coagulation, can reduce biological fouling. The cleaning method for removal of biological fouling is Chemically Enhanced Backwash (CEB) with oxidizers or biocides (NaOCl,H2O2, SBS). Shock chlorination can also be effective for biological fouling control. Inorganic fouling is caused by the precipitation of inorganics on the membrane. The rate of inorganic fouling can be controlled through oxidation/precipitation and/or filtration as pretreatment to the UF or in some cases reducing the hardness of the feed water. The recommended cleaning method for removal of inorganic fouling is chemically enhanced backwash with acid at pH 2 (HCl, H2SO4, Citric, Oxalic Acid).Organic fouling is caused by organics adsorbing on the membrane (silt, organic acids, humus). PAC, GAC, or coagulation can be used to control the rate of organic fouling. The common cleaning method for removal of organic fouling is CEB with alkali at pH 12 (NaOH).5. Operating Information5.1 Start UpThe following procedures should be followed for start-up of DOW TM IntegraPac™ Ultrafiltration Modules and Skids. Manually start the equipment during initial operation. Flush the UF system to remove the storage solution used in shipping before starting the equipment. Target a filtrate flow of 60% of design during initial operations. After 24 hours the filtrate flow can be adjusted to design conditions.Pre-start checks1. The UF pre-treatment system should operate properly and the UF feed water should meet the design requirements. Ensure that chemical addition points are properly located and that proper mixing of chemicals in the feed streams can occur. Check the addition of pretreatment chemicals.2. Verify that the drain/waste collection system is functional3. Verify that the PLC program is loaded and functioning4. Complete an electrical system check. Verify that the instrumentation is working and calibration is completed. Calibrate gauges and meters based on manufacturers’ recommenda tions.5. Clean and connect interconnecting piping. Flush system without modules to remove fabrication debris. During the flushing operation, check all pipe connections and valves for leaks. Tighten connections where necessary.6. Residual air should be removed from the system during start-up.Start UpCheck that all valves are closed and pumps are off before starting the system. Start the equipment by following the steps below:1.Pumps should be aligned, lubricated, and properly rotated.2.Open valves and start the feed pump3.Fill system and start a flush4.Start the backwash pump5.Set and adjust the backwash pressure6.Set and adjust the inlet air pressure7.Set backwash time interval8.Set air scour time interval9.Set backwash sequence。

陶氏超滤膜技术参数一、超滤水办理应用术语不对称膜Asymmetric Membrane 人工合成聚合中空纤维，由一层均匀致密的、很薄的外皮层及起支撑作用的海绵状内层构造组成，这层均匀、致密的外皮层起真实截留污染物的作用。

原水Feed进入超滤系统的水产水Filtrate透过超滤膜的水，基本上无悬浮颗粒、胶体和微生物等产水透过超滤膜的流率，往常表达为单位时间内单位膜通量面积的产水量，单位为LMHFlux跨膜压差Trans-membrane Pressure 简称TMP，即产水侧和进水侧压力的差别，即膜双侧压力差；如为错流过滤，为产水侧和进水出入口压力均匀值的差别气擦洗Air Scour 让无油压缩空气经过中空纤维膜丝的进水侧表面，经过压缩空气与水的混淆振荡作用，松动并冲走膜表面过滤过程中截留的污染物把等同于产水质量的水从中空纤维膜丝的产水侧反向输反洗Backwash向进水侧，松动并冲走膜表面的污染物利用超滤进水泵把进水从中空纤维膜的进水侧进入，从正洗Forward Flush浓水侧排出，进一步冲洗膜表面的污染物化学增强反洗Chemical Enhanced Backwash 在反洗水中加入拥有必定浓度和特特成效的化学药剂，经过浸泡、气擦洗等方式，将膜表面的污染物冲洗下来的方式化学冲洗Cleaning In Place 简称CIP，即用配置好的酸、碱或杀菌剂化学药剂从进水侧进入中空纤维膜，从浓水侧和产水侧循环回流到冲洗水箱进行冲洗的方式，将膜表面的污染物有效去除回收率Recovery产水占原水的百分比将膜截留的物质从膜组件浓水口排放掉，防备被截留的浓水排放过滤Concentrate Bleed物质在膜进水侧发生累积错流过滤Cross Flow进水沿平行于膜面方向流动，有助于冲洗膜表面的污染物第1页/共11页二、陶氏DOW TM超滤膜产品一览表SFP‐2880超滤膜组件长度规格（80‐80英寸长，60‐60英寸长）超滤膜组件公称直径规格（8‐8英寸直径，6‐6英寸直径）陶氏超滤膜资料属性代号（2‐PVDF）陶氏超滤产品型号（SFP‐用于预办理，SFD‐用于饮用水）表2-1超滤膜组件的膜资料膜资料名称膜资料缩写代号聚砜PS1聚偏氟乙烯PVDF2聚醚砜PES3聚丙烯腈PAN4聚丙烯PP5聚乙烯PE6醋酸纤维素CA7芬芳聚酰胺APA8聚氯乙烯PVC9重生纤维素RC10表2-2超滤膜组件的用途说明产品型号用途划分SFP预办理SFD中水/污水回用SFR饮用水办理第2页/共11页表2‐3不一样超滤膜资料的接触角数据序号膜资料接触角01纤维素（CA）12~45°02聚醚砜（PES）44~81°03聚丙烯（PP）108°04聚砜（PS）38~81°05聚偏氟乙烯（PVDF）30~66°备注：值越小，表面资料越亲水，越亲水抗污染性能就越好。

DOW TM超滤膜的运行与操作一、过滤超滤膜系统在启动时，建议进行2-3 分钟的正洗来除去膜组件里残留的化学品及空气。

正洗是进水从膜组件下部进水口进入膜组件，冲洗膜丝外表面，从膜组件顶部浓水口排出，这一步骤时间内将不过滤进水。

在正洗完成后，系统可以转换到过滤运行状态。

通常一个运行周期为20-60 分钟，根据进水条件和清洗程序而变化。

在正常的过滤状态下，100%的进水被过滤即全流过滤。

由于在过滤过程中截留污染物，跨膜压差(TMP)将会上升，在预先设定的运行步骤的结尾，会转入到气擦洗和反洗的清洗步骤。

二、气擦洗超滤膜系统按照自动控制程序将转入气擦洗步骤，气擦洗是利用压缩空气产生的气泡松动膜丝外表面截留的污染物。

压缩空气从膜组件底部进气口进入到膜丝外表面，从顶部浓水口排出。

三、底部排水在气擦洗步骤后，停止进气，打开下排放阀，将膜组件重力排干，随排水带走松动的污染物。

排水完毕之后进行第一步反洗，即上反洗步骤。

反洗水从膜组件上部产水口进入膜丝内部，从与运行产水相反的方向透过膜丝，反洗废水在膜丝外部汇集，打开反洗上排放阀，使反洗废水从膜组件顶部浓水口排出。

上反洗步骤能首先清洗膜组件污染最严重的上端区域。

第二步反洗，即下反洗步骤，去除膜组件下端区域的污染物。

保持反洗水从膜组件上部产水口进入，打开反洗下排放阀，使反洗废水从膜组件下部进水口排出，可有效去除下端的污染物。

六、正洗在反洗结束后，需进行正洗以去除任何残留的污染物和/或化学药品，并排除聚集在膜组件内部的空气。

完成正洗后，超滤系统即可重新投入到过滤运行状态或者备用状态。

七、化学加强反洗（CEB）在通过常规气擦洗辅助反洗步骤无法除去所有污染物的情况下，通过在反洗时加入化学药剂可以加强反洗的效果，即化学加强反洗（CEB, C hemical E nhanced B ackwash）。

CEB 过程包括一个气擦洗过程、加入化学药剂反洗、浸泡和将污染物和化学药剂冲出的常规气擦洗辅助反洗过程。

陶氏反渗透膜超滤膜活性炭过滤安全操作及保养规程前言
陶氏反渗透膜、超滤膜和活性炭过滤是现代水处理技术中常用的三
种方法，可广泛应用于饮用水、制药、食品饮料、化工和电子等领域。

本文旨在介绍这三种技术的基本原理、安全操作要点和保养规程，以
确保使用者在使用这些设备时遵循正确的操作程序，从而最大限度地
提高设备的使用寿命和处理水的质量。

一、陶氏反渗透膜
1. 原理
陶氏反渗透膜（Reverse Osmosis，RO）是一种利用高压迫使水通
过半透膜，将水中的溶质和离子分离的技术。

反渗透膜是一种半透膜，膜孔径小于100埃，可以有效地过滤掉水中的细菌、病毒、溶质和游
离离子，从而达到除盐、脱色、脱菌和净化水的目的。

反渗透膜通常
是由多层净化材料构成，保证传质的效率和质量。

2. 安全操作要点
反渗透膜在使用过程中需要特别注意以下操作要点：
•避免使用不符合要求的水源；
•确保给水水压稳定；
•保证压力容器密封性完好；
•定期检查反渗透膜和各种管路的状况；。

超滤工作原理超滤是一种常见的膜分离技术，广泛应用于水处理、污水处理、食品和饮料工业等领域。

它通过使用超滤膜，将溶解物、胶体、大分子有机物等从水中分离出来，实现液体的分离和浓缩。

超滤膜是一种孔径在0.001-0.1微米之间的多孔膜，通常由聚合物材料制成。

超滤过程中，待处理的液体被施加在超滤膜的一侧，而膜的另一侧则形成了一个低压区域。

液体中的溶解物和胶体颗粒无法通过超滤膜的孔隙，而水分子和小分子物质则可以通过膜孔隙进入低压区域。

超滤工作原理可以概括为以下几个步骤：1. 预处理：在超滤过程开始之前，通常需要对待处理的液体进行预处理。

这包括去除大颗粒物质、悬浮物和杂质，以防止它们堵塞超滤膜孔隙。

2. 进料：待处理的液体被送入超滤系统中，通过泵或重力作用进入超滤膜。

3. 分离：液体中的溶解物、胶体和大分子有机物无法通过超滤膜的孔隙，被阻隔在膜的一侧，形成浓缩液。

而水分子和小分子物质则可以通过膜孔隙进入低压区域，形成透过液。

4. 控制：超滤过程中，可以通过调节进料压力、调整膜孔隙大小和使用不同的膜材料来控制分离效果。

较高的进料压力和较小的膜孔隙可以提高分离效率，但也会增加能耗和操作难度。

5. 收集：浓缩液和透过液分别从超滤膜的两侧收集。

浓缩液可以进一步处理或回收利用，而透过液则可以直接使用或进一步处理。

超滤工作原理的优势包括：1. 高效分离：超滤膜的孔隙可以选择性地分离不同分子大小的物质，具有较高的分离效率和选择性。

2. 无需加热：相比于其他分离技术，超滤不需要加热操作，可以节省能源和操作成本。

3. 操作简便：超滤系统通常结构简单，操作方便，易于维护和管理。

4. 无化学添加剂：超滤过程中不需要添加化学药剂，避免了对环境的污染和对人体的危害。

超滤工作原理的应用领域广泛，包括但不限于以下几个方面：1. 水处理：超滤可以用于海水淡化、饮用水净化、工业废水处理等领域，去除溶解物、胶体、细菌等。

2. 食品和饮料工业：超滤可以用于果汁澄清、乳品浓缩、啤酒酿造等过程，提高产品质量和延长保质期。

超滤系统工作原理
超滤系统是一种物理分离技术，利用超滤膜筛选溶液中的溶质和颗粒物质。

其工作原理是基于压力驱动，将溶质通过微孔隔离。

以下是超滤系统的工作原理：
1. 进料：需要处理的溶液被引入超滤系统中，通常是通过管道连接到超滤膜的一侧。

2. 压力驱动：在超滤系统中施加一定的压力，如液体泵或其他压力装置，使溶液在超滤膜上形成一定的压力差。

3. 分离：超滤膜的孔径大小一般在0.01-0.1微米之间，根据溶质颗粒的大小选择合适的膜孔径。

较大的分子、颗粒物质和悬浮物将被留在超滤膜的一侧，而较小的分子和溶质则能通过超滤膜的微孔，形成过滤物。

4. 收集：超滤膜另一侧通过管道收集所得的过滤物，也即留在膜表面的较大分子和颗粒。

5. 结果：通过超滤系统处理后，溶液中的大部分悬浮颗粒和高分子物质被分离，产生的过滤物质较为纯净。

需要注意的是，超滤系统是一种物理分离方法，不改变原溶液中溶质的化学结构和溶解状态，而主要实现对颗粒、胶体和大分子物质的分离。

陶氏UF超滤膜的内压式与外压式的区别
2019.11.26
UF超滤膜是以压力为驱动力，利用合成的高分子半透膜高精度的截留性能进行固液分离或使不同分子量物质分级的超
滤膜法分离技术。

本文介绍了UF超滤膜的内压式与外压式的区别。

超滤所用的膜为不对称膜，它的特点是膜断面形态的不对称性，它是由表面活性层与大孔支撑层两层组成，表面活性层很薄，厚度0.1-1.5m膜的分离性能主要取决于这一层，表面活性层有孔径1~20nm的膜为超滤膜;支撑层的厚度为50~250m，起支撑作用，它决定膜的机械强度，呈多孔状，超滤膜的大孔支撑层为指状孔。

内压式组件的分离层在纤维的内表面。

主要部件包括：中空纤维膜、压力容器、封头和管接头及密封件。

使用时，料液从组件的一端进入，在中空纤维的内腔流动，在压力的作用下，一部分溶剂和小分子物质透过超滤膜成为产水，另一部分溶剂和大分子物质沿内腔流向组件的另一端，成为浓水。

与内压式相似，但纤维的分离层在外表面。

料液从组件的进水端进入中心布水管，并把料液均匀的分配开来，浓缩液从组件的侧口排出，透过液在纤维内腔流向另一端。

以上由莱特莱德小编整理。

陶氏4英寸纳滤膜分离机理的介绍
2020.07.20
陶氏4英寸纳滤膜分离机理的介绍
陶氏4英寸纳滤膜很多人都听说过，随着纳滤膜广泛应用，其中纳滤膜的分离机理深受大家的关注，那么纳滤膜分离机理是什么呢?下面，小编就来为大家介绍关于纳滤膜的分离机理，让你对陶氏4英寸纳滤膜会更加的了解。

就目前提出的纳滤膜机理来看, 大部分人认为，陶氏4英寸纳滤膜的分离作用主要是粒径排斥和静电排斥。

对于非荷电分子，分离机理主要是筛滤或粒径的排斥;离子的分离机理是筛滤和静电排斥。

陶氏4英寸纳滤膜的分离溶质的机理与反渗透膜是一样的，通过反渗透的方式进行分离：以选择性透过溶剂水膜将两溶液隔开，左边为纯溶剂水，右边为含溶质的稀溶液。

以上就是为大家介绍的陶氏4英寸纳滤膜分离机理是怎样的相关内容，希望对您有帮助。

如果想要了解更多，欢迎大家咨询。

超滤膜种类分析和工作原理超滤膜，是一种孔径规格一致，额定孔径范围为0.001-0.02微米的微孔过滤膜。

在膜的一侧施以适当压力，就能筛出小于孔径的溶质分子，以分离分子量大于500道尔顿、粒径大于2～20纳米的颗粒。

超滤膜是最早开发的高分子分离膜之一，在60年代超滤装置就实现了工业化。

有机膜有机膜主要是由高分子材料制成，如醋酸纤维素、芳香族聚酰胺、聚醚砜、聚偏氟乙烯等等。

根据膜形状的不同，可分为平板膜、管式膜、毛细管膜、中空纤维膜等。

目前，市面上家用净水器用的膜基本上都是中空纤维膜。

无机膜无机膜中，陶瓷超滤膜在家用净水器中应用比较多。

陶瓷膜寿命长，耐腐蚀，但出水有土味，影响口感。

同时陶瓷膜易堵塞，清洗不易。

中空纤维超滤膜由于其填充密度大，有效膜面积大，纯水通量高，操作简单易清洗等优势，被广泛应用于家用净水行业。

陶氏超滤膜筛分过程，以膜两侧的压力差为驱动力，以超滤膜为过滤介质，在一定的压力下，当原液流过膜表面时，超滤膜表面密布的许多细小的微孔只允许水及小分子物质通过而成为透过液，而原液中体积大于膜表面微孔径的物质则被截留在膜的进液侧，成为浓缩液，因而实现对原液的净化、分离和浓缩的目的。

每米长的超滤膜丝管壁上约有60亿个0.01微米的微孔，其孔径只允许水分子、水中的有益矿物质和微量元素通过，而最小细菌的体积都在0.02微米以上，因此细菌以及比细菌体积大得多的胶体、铁锈、悬浮物、泥沙、大分子有机物等都能被超滤膜截留下来，从而实现了净化过程。

在单位膜丝面积产水量不变的情况下，滤芯装填的膜面积越大，则滤芯的总产水量越多。

其计算公式为：S内=πdL×n S外=πDL×n其中：S内为膜丝总内表面积;d为超滤膜丝的内径;S外为膜丝总外表面积;D为超滤膜丝的外径;L为超滤膜丝的长度;n为超滤膜丝的根数。

内压式和外压式中空纤维超滤膜一支超滤膜由成百到上千根细小的中空纤维丝组成，一般将中空纤维膜内径在0.6-6mm之间的超滤膜称为毛细管式超滤膜，毛细管式超滤膜因内径较大，不易被大颗粒物质堵塞。

超滤膜的工作原理和操作方法超滤膜的工作原理和操作方法一、工作原理过滤是使液体通过多孔过滤介质以分离其中所含的固体颗粒的一种操作。

过滤介质截阻颗粒而让液体通过，随着被分离的颗粒变小，要求介质的通道也要变小。

如果颗粒小到亚微细粒的程度，膜孔大小就要趋近于能阻止溶液中大分子的通过。

这种利用半透膜的微孔过滤以截留溶液中大溶质分子的操作称为超滤，而这样的半透膜称为超滤膜。

超滤的驱动力是压力，通常高达1.0MPa。

运用液压迫使溶液透过膜并按溶质分子大小、形状等差异，把大溶质分子阻留在膜的一侧，成为浓缩液; 而小分子的溶质则随溶剂透过膜到另一侧，成为透过液流出。

如果将所得浓缩液用水稀释，再进行超滤，可使料液中的低分子溶质进一步随透过液流出，而高分子物质逐步得到提纯，这样的过程称为全滤(如图8-4)。

超滤具有分离和提纯的作用。

1. 分离作用图8-4 超滤原理示意图1—进料2—浓缩液3—清液4—超滤膜低分子质量的溶质随溶媒一起透过滤膜，高分子质量的溶质被截留，因此，料液被分为带有低分子溶质的透过液和带有高分子溶质及残留低分子溶质的浓缩液。

2. 提纯作用由于分离，提高了浓缩液中总固体里高分子量溶质的百分率，因此，提纯了高分子溶质。

在透过液中，低分子溶质由于从高分子溶质中分离出来，也得到了提纯。

二、超滤膜(一)超滤膜的膜渗机理料液在超滤膜内的流动问题比较复杂，简单的床层流动理论不能充分解释膜内的流动，它不是单纯属于一般毛细管内层流的机理。

通常膜渗机理有下述两种模型：1. 毛细流动模型在这种模型中，溶质的脱除主要靠流过微孔结构的过滤或筛滤作用，半透膜阻止了大分子的通过，按这一模型建立的流动是毛细孔中的层流流动。

2. 溶解扩散模型在这种模型中，假定扩散质的分子，先溶解于膜的结构材料中，而后再经载体的扩散而传递。

因为分子种类不同，溶解度和扩散度也就不同。

实际上，两种模型在膜渗传递中都可能存在，但反渗透以溶解扩散机理占优势，而超滤则以毛细流动机理占优势。

超滤膜使用说明一、预备工作a.首先检查电控柜是否通电，并保证合上所有的空开。

b.超滤进水口压力控制在0.25Mpa以内（即超滤膜初始运行时，在保证设计通量的前提下，如果此时压力低于0.25 Mpa，那么就在此压力下运行，不需要提高到0.25Mpa，这样能有效延长膜元件的使用寿命），反冲流量：>产水量的1.5倍，反冲压力: 0.15Mpa--0.25Mpa注意：膜反冲主要关注的是透过膜的水量也就是反冲量必须大于产水量的1.5倍，反冲通过量在规定的压力内越大越好，即反洗泵选型时, 在0.25Mpa条件下流量最少应是产水量的1.5倍)。

c.初始状态上述一切准备就绪后，打开手动阀F1、F2、F3、F4、F5、F6、F7、B1（关闭程度按浓水流量及回流比调节好）其余手动阀F8、F9处于关闭状态（即为正常的停机状态）。

二、典型工艺：图上标示的文字：原液为进水口，超滤液为透过液口(又为反洗进口)，浓缩液为浓缩液回流口（又为排污口）。

用户为了节省组装费用可只需利用一个浓缩液口作为浓水回流口，可用4~5mm的UPVC板（采用车床加工成与膜端口橡胶垫片一样尺寸）堵住其中靠近进液口的那个浓缩液口。

请务必注意ESUF超滤膜元件的原液进口中间有导流分布管，它只能作为进水口，不能作为排水口，远离进水口的侧面浓缩口可作为排污口。

三、超滤流程图（见附图）及运行设备正常投运的基本工作流程示意如下：运行水反洗排污运行（40分钟）（30秒）（15秒）A、自动运行（所有手动阀门均在初始状态）打开气动阀门V1、V2、V3，数秒钟（待定）后开启原水泵、措流泵（清洗泵），并按流量计调节B1使浓水排放流量为4m3/h左右，使措流量与透过液流量比尽可能大（注意如错流水泵足够大并产水量足够的话，F5阀门尽量多打开一点，以提高回流比，增加错流程度）。

进水压力应在0.25Mpa以内(产水量足够的话，进水压力越低越好)。

B、大流量水反冲设备运行40分钟后(注：运行时间以V1打开时计数)开始对设备进行水反洗。

超滤工作原理超滤是一种常用的分离技术，广泛应用于水处理、食品加工、制药等领域。

它通过使用超滤膜，将溶液中的大分子物质、悬浮物和微生物等分离出来，同时保留溶液中的小分子物质和溶质。

超滤膜是一种多孔性薄膜，由聚合物材料制成。

其孔径通常在0.001至0.1微米之间，可以根据需要选择不同孔径的超滤膜。

超滤膜的孔径比微滤膜小，但比逆渗透膜大。

超滤过程主要包括预处理、过滤和清洗三个步骤。

1. 预处理：在超滤过程开始之前，需要对原料溶液进行预处理。

这包括去除悬浮物、调整溶液的pH值和温度等。

预处理的目的是保护超滤膜，防止其被堵塞或受到损害。

2. 过滤：预处理完成后，原料溶液被送入超滤装置。

超滤装置通常由滤芯、滤床和滤饼等组成。

原料溶液通过超滤膜，大分子物质、悬浮物和微生物等被截留在膜表面，而小分子物质和溶质则通过膜孔进入滤液中。

3. 清洗：当超滤膜的通量降低或膜面出现堵塞时，需要进行清洗。

清洗的方法有物理清洗和化学清洗两种。

物理清洗包括反冲洗和超滤液冲洗，可以通过施加压力或改变流动方向来清除膜面的污染物。

化学清洗则使用特定的清洗剂来溶解和去除污染物。

超滤的工作原理基于分子的大小排斥效应。

超滤膜的孔径较小，无法通过大分子物质和悬浮物，但可以通过小分子物质和溶质。

当溶液施加一定的压力，溶液中的物质会根据其分子大小和溶液中的浓度梯度，通过超滤膜的孔隙进入滤液中。

这样，大分子物质、悬浮物和微生物等被截留在膜表面，而小分子物质和溶质则通过膜孔进入滤液中。

超滤的工作原理还受到溶液的粘度、温度和压力等因素的影响。

较高的压力可以增加通量，但也会增加膜的压力和损坏的风险。

较高的温度可以改善溶液的流动性，但也可能导致膜的变形或破裂。

因此，在超滤过程中需要根据具体情况选择适当的操作参数。

总结起来，超滤是一种通过使用超滤膜将溶液中的大分子物质、悬浮物和微生物等分离出来的分离技术。

它的工作原理基于分子的大小排斥效应，通过施加一定的压力，使溶液中的小分子物质和溶质通过超滤膜的孔隙进入滤液中，而大分子物质、悬浮物和微生物等被截留在膜表面。

陶氏超滤产品技术手册作为一家全球领先的工程材料和科学研究公司，Dow公司致力于为客户提供各种高质量的工程材料以及创新的科技。

在这些产品中，陶氏超滤产品是其中之一。

陶氏超滤产品是一种用途广泛的膜技术，能够通过分离物质颗粒大小来过滤清洁水源或废水，有效地净化水质。

陶氏超滤技术已经在许多工业、商业和家庭环境中得到了广泛应用。

为了帮助客户更好地了解陶氏超滤技术，Dow公司发布了陶氏超滤产品技术手册。

该手册详细介绍了陶氏超滤膜的构成和产生原理，以及超滤膜的物理性质和处理效果。

此外，手册还介绍了如何根据不同的水源和用途选择适当的超滤膜，并且为客户提供了使用陶氏超滤膜的有效方案。

手册包含以下内容：第一部分：超滤膜的概述手册的第一部分提供了陶氏超滤膜的概述。

超滤膜是由几种不同材料组成的多层复合膜，这些材料通常是聚酰胺（PA）及聚碳酸酯（PC）。

超滤膜能够过滤出直径可达0.1微米的颗粒，能够有效地过滤水中的细菌、病毒、有机物和一些重金属等污染物。

第二部分：超滤膜的物理性质手册的第二部分介绍超滤膜的物理和化学性质。

超滤膜具有一定的孔径大小，因此，它能够过滤物质的颗粒大小是有限制的。

此外，超滤膜还有很好的抗氧化和耐腐蚀性能，能够适应各种复杂的水质环境。

第三部分：超滤膜的应用手册的第三部分介绍了超滤膜的应用，包括工业和商业的应用。

超滤膜广泛应用于制药、电子、化工、食品和饮料生产、废水处理、海水淡化和饮用水净化等领域。

此外，超滤膜还可以应用于家庭饮用水净化器中，提供家用净水服务。

第四部分：根据不同水源选择超滤膜手册的第四部分介绍了如何根据不同的水源选择超滤膜。

手册提供了一些关于选择超滤膜的建议和技巧，这些建议和技巧能够帮助客户选择出适合自己需要的超滤膜。

选择适当的超滤膜不仅可以提高处理水的效率，还能够有效地减少能耗和成本。

第五部分：使用超滤膜的有效方案手册的第五部分介绍了使用超滤膜的有效方案，例如在废水处理中的应用。

该部分还提供了超滤膜的周期维护技巧和操作方法。

陶氏超滤膜的运行与操作DOW TM超滤膜的运行与操作一、过滤超滤膜系统在启动时，建议进行2-3 分钟的正洗来除去膜组件里残留的化学品及空气。

正洗是进水从膜组件下部进水口进入膜组件，冲洗膜丝外表面，从膜组件顶部浓水口排出，这一步骤时间内将不过滤进水。

在正洗完成后，系统可以转换到过滤运行状态。

通常一个运行周期为20-60 分钟，根据进水条件和清洗程序而变化。

在正常的过滤状态下，100%的进水被过滤即全流过滤。

由于在过滤过程中截留污染物，跨膜压差(TMP)将会上升，在预先设定的运行步骤的结尾，会转入到气擦洗和反洗的清洗步骤。

二、气擦洗超滤膜系统按照自动控制程序将转入气擦洗步骤，气擦洗是利用压缩空气产生的气泡松动膜丝外表面截留的污染物。

压缩空气从膜组件底部进气口进入到膜丝外表面，从顶部浓水口排出。

三、底部排水在气擦洗步骤后，停止进气，打开下排放阀，将膜组件重力排干，随排水带走松动的污染物。

排水完毕之后进行第一步反洗，即上反洗步骤。

反洗水从膜组件上部产水口进入膜丝内部，从与运行产水相反的方向透过膜丝，反洗废水在膜丝外部汇集，打开反洗上排放阀，使反洗废水从膜组件顶部浓水口排出。

上反洗步骤能首先清洗膜组件污染最严重的上端区域。

第二步反洗，即下反洗步骤，去除膜组件下端区域的污染物。

保持反洗水从膜组件上部产水口进入，打开反洗下排放阀，使反洗废水从膜组件下部进水口排出，可有效去除下端的污染物。

六、正洗在反洗结束后，需进行正洗以去除任何残留的污染物和/或化学药品，并排除聚集在膜组件内部的空气。

完成正洗后，超滤系统即可重新投入到过滤运行状态或者备用状态。

七、化学加强反洗（CEB）在通过常规气擦洗辅助反洗步骤无法除去所有污染物的情况下，通过在反洗时加入化学药剂可以加强反洗的效果，即化学加强反洗（CEB, Chemical Enhanced Backwash）。

CEB 过程包括一个气擦洗过程、加入化学药剂反洗、浸泡和将污染物和化学药剂冲出的常规气擦洗辅助反洗过程。

专注水处理及流体分离技术
陶氏DOW超滤膜有哪些过滤方式？
以陶氏DOW超滤膜为过滤介质，在一定压力下当原液流过膜表面时，超滤膜表面密布的许多细小的微孔只允许水及小分子物质通过而成为透明液，而原液中体积大于膜表面微孔的物质则被截留在膜的进液侧，成为浓缩液，因而实现对原液的净化、分离和浓缩的目的。

今天，小编就给大家介绍下陶氏DOW超滤膜有哪些过滤方式吧。

1、内压式过滤
过滤时液体从中空纤维内进入，小分子物质透过膜到中空纤维外成为透过液，胶体、细菌等大分子物质被膜截留于中空纤维内，而成为浓缩液。

2、外压式过滤
过滤时液体从中空纤维外进入，小分子物质透过膜到中空纤维内成为透过液，大分子物质被膜截留于中空纤维外，而成为浓缩液。

3、错流过滤
错流过滤因为有浓缩液排放，在膜表面可形成较大剪切力，从而有效降低膜的污染。

错流过滤的浓水流量与产水流量的比为回流比，对于较差的水质，可选择高的回流比，以减轻膜的污染，一般在1%–100%甚至更大，浓水回到原水箱或是预处理的入口，重新进入超滤系统进行过滤处理，也可添加循环泵使浓水循环。

4、死端过滤
又叫全量过滤，过滤时没有浓水排出，污染物全部被截留在膜表面，只能通过定期的反冲洗将其排出。

这种操作方式适用于进水水质较好的情况下，因为没有浓水排放，因而能耗低。

上述就是陶氏DOW超滤膜的过滤方式，希望对大家有所帮助。

北京立川环保愿与您携手共同呵护环境。

陶氏4英寸纳滤膜使用注意事项及优势
陶氏4英寸纳滤膜使用注意事项及优势
陶氏4英寸纳滤膜是目前较为优质的有机膜元件之一，在水处理行业中应用较为广泛，该系列膜元件因使用性价比较高，受到了广大用户的青睐。

下面为大家分享陶氏4英寸纳滤膜使用注意事项及优势：
一、陶氏4英寸纳滤膜使用注意事项：
一般陶氏4英寸纳滤膜组件在出厂前都会密封保存在定量保护液中，因此在使用前需要现冲洗后使用。

在冲洗时应注意首先需低压冲洗1个小时，然后再用高压冲洗1个小时，无论是高压冲洗时间段还是低压冲洗时间段，均要把产水排放阀打开。

在使用陶氏4英寸纳滤膜组件时一定要轻拿轻放，注意正确操作方式，因为陶氏4英寸纳滤膜组件属于精密耗材，如出现任何纰漏，都会使其受到损坏，从而影响最终处理效果。

当设备停用时建议用户将膜元件清洗干净后、进行杀菌消毒，然后将其密封。

二、陶氏4英寸纳滤膜应用优势：
陶氏4英寸纳滤膜具有良好的截留性能和膜通量，陶氏4英寸纳滤膜设备控制系统可依据用户需求进行个性化设计，并采用高端控制软件，从而实现高标准监控设备运行参数，预防
人工操作失误。

该设备回收率高、陶氏4英寸纳滤膜性能高，可实现物料高效分离、纯化和浓缩，而且在处理过程中无相变，对原料组成成分不会造成不利影响，整个过程始终处理常温状态，有效避免了高温对某些物质的破坏。

整套设备自动化程度高、操作便捷。

陶氏4英寸纳滤膜应用技术不断提升，给用户使用带来很大的便利，有效降低成产成本的投入，提高企业经济效益。