freshpoint ultrafiltration system -...

FILTRATION & PROCESS

FRESHPOINT® ULTRAFILTRATION SYSTEM APPLICATIONS GUIDE

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TABLE OF CONTENTS2 USING THIS GUIDE

3 HOW ULTRAFILTRATION WORKS MEMBRANE CONSTRUCTION FILTRATION OPERATION FLOW DIRECTION

5 ULTRAFILTRATION APPLICATIONS

6 WATER QUALITY BASICS WATER SOURCES SEASONAL VARIATIONS WATER IMPURITIES WATER ANALYSIS

7 FEED WATER QUALITY AND PRETREATMENT REQUIREMENTS

GENERAL FEED WATER SURFACE WATER WELL WATER PURE WATER

9 FILTERED WATER QUALITY TYPICAL FILTERED WATER QUALITY

9 SYSTEM SIZING MEMBRANE FLUX RATES TEMPERATURE CORRECTION

FACTOR

10 OPERATING GUIDELINES

11 SYSTEM CONFIGURATIONS AUTOMATIC FLUSHING OPERATION STORAGE TANKS

13 SHIPPING AND HANDLING CAREFUL TRANSPORT AND HANDLING STORAGE

13 SYSTEM STARTUP GUIDELINES PIPING FLUSHING SYSTEM DISINFECTION

13 MEMBRANE RINSING

14 SYSTEM SANITIZING

15 MEMBRANE INTEGRITY TEST GENERAL TEST INFORMATION EQUIPMENT PROCEDURE

16 MEMBRANE CLEANING MONITORING MEMBRANE

PERFORMANCE FOR FOULING NORMALIZING FLOW DATA BEFORE CLEANING CLEANING PROCEDURE

18 MEMBRANE STORAGE AFTER USE

18 BASICS OF FOULING

19 ULTRAFILTRATION TERMS

20 FREQUENTLY ASKED QUESTIONS

22 TROUBLESHOOTING GUIDE

23 MEMBRANE DATA SHEET FRESHPOINT® MODEL U440

USING THIS GUIDEThis guide is intended to provide general guidance to users regarding installation, operation, and maintenance of ultrafiltration systems including:

•Applications •Feedwaterrequirements •Pretreatmentrequirements •Systemsizing •Performance •Membranemaintenance

Thisguideisintendedforusebywatertreatmentprofessionalswhohavesomefamiliaritywithmembranesusedforwatertreatment.ItisrecommendedforuserstohavecompletedtheWQA® Reverse Osmosis/Ultrafiltration Specialty Exam,orhaveequivalentexperiencewithmembranetreatmentbasics.

For detailed information on specific ultrafiltration systems, please refer to its corresponding operating and maintenancemanualandproductdatasheet.

FRESHPO INT® U LTRAF I LTRAT ION GU IDE 3

Fulvic Acids

Atomic Mass(Dalton DA)

Particle Size, µm

100

0.0001 0.001 0.01 0.1 1.0 10 100

10,000 1,000,000 108 109

Humic Acids

CellFragments

Bacteria

Virus

Ultrafiltration

Clay ParticlesHuman

Hair

CryptosporidiumCysts

Giardia LambliaCysts

Suspended Solids Test (TSS)

Organic Debris and Bacterial Flocs

Silt Particles

AqueousSalt

SugarMolecule

MetalIon

Colloidal Silica

Colloidal Material

HOW ULTRAFILTRATION WORKSUltrafiltration(UF)isamembraneseparationprocessthatallowsforreductionofsuspendedsolidsincludingparticles,colloids,cysts,bacteria,andvirusesbymechanicalmeans.UFmembranesremovesuspendedsolidsbasedonporesize.TheporesizefilteredbyUFmembranesvarieswidelydepending on the material, manufacturing process, and the intended use/application of the specific membrane.(Seechartbelow).

Membrane Construction Ultrafiltrationmembranesareavailableinanumberofconfigurationsincluding:Flat sheet –Membranesformedinflatsheets,andconfiguredeitherinplate-and-framemembranestacksorspiralwoundcartridges.Typicallyusedforwatersuppliesthatdonothaveahighpotentialforfoulingandconfiguredforcross-flowfiltrationwithacontinuousrecirculation/wasteflow.Hollow fiber –Membranesformedintohollowfibersandconfiguredinmodulescontainingmultiplefibers.Typicallyoperatedinadeadendmode(i.e.nocontinuouswasteflow).Flowcanbeeitherfromthefiberboretotheexterior(insideout)orfromthefiberexteriortothebore(outsidein).Multi-bore hollow fiber –Similartohollowfibermembranesexceptthatthefibersarelargerandeachfibercontainsmultiplebores(typicallyfourtosevenbores).Tubular –Membranessimilartohollowfiberbutwithtubesthataremuchlarger(0.5"to1"ID).Typicallyusedforwastewaterapplicationsandconfiguredforcross-flowfiltrationwithacontinuousrecirculation/wasteflow.NOTE: Thisguidecoversonlyhollowfiberandmulti-borehollowfibermembranes.Thesetwotypesoffibermembranesarepreferredduetotheirrobustdesignandtheabilitytobecleaned“online”byperiodicflushing.

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Particles, colloids,etc. are retained bythe membrane wall

Waterstream

Particles,colloids, etc.

Water freely passes through membrane wall

Simplified UF Fiber Diagram

Thefigurebelowdepictsanindividualultrafiltrationhollowfibermembraneflowinginsideout. Waterandparticulatesenterthecenterofthehollowfiber.Waterpassesthroughthemembranewallwhereitiscollectedasfiltrate,whileparticleslargerthanthemembraneporesareretainedbythemembrane.Theseparticlesareretainedinsidethefiberboreuntilaflushcycleisactivated.

HOW ULTRAFILTRATION WORKSFiltration Operation

Ultrafiltrationsystemsmaybeconfiguredtooperateinoneofthreebasicfiltrationmodes:•Cross-flow–Aportionofthefeedwateriscontinuouslyrecirculatedand/orflowstowastetopreventretainedsolidsfrombuildinguponthemembranesurface.

•Deadend–Thereisnowasteflowfromthesystem.Whenthefilterbecomespluggeditiscleaned orreplaced.

•Deadendwithperiodicflushing–Thereisnocontinuouswasteflow.Themembraneisperiodicallyflushedtoremoveretainedsolidsfromthemembranesurface.

NOTE: Thisguidefocusesonsystemsconfiguredfordeadendfiltrationwithperiodicflushingonly.

Flow DirectionHollowfibermembranescanbeconstructedtoallowinsideoutoroutsideinflowinadeadendmode.Inside out flow:Feedwatertravelsdowntheboreofthefiberandpassesthroughthefibertotheoutsidewhereitiscollectedastreated(filtrate)water.Outside in flow:Feedwaterisontheoutsideofthefiberandpassesthroughtotheinsideofthefiberwhereitiscollectedastreated(filtrate)water.Thepreferredmembraneconfiguration(insideoutoroutsidein)isdependentupontheconstructionmethodandintendeduse.Outsideinmembranesarepreferredforwaterswithveryhighsuspendedsolidsandareprimarilyappliedinwastewaterapplicationssuchasmembranebioreactorsusedforsewagetreatment.Insideoutmembranesaremoreefficientandrequirelowervolumesofwaterforflushing,sotheyarepreferredforapplicationswithlowerlevelsofsuspendedsolidssuchasprefilteredwellorsurfacewater.NOTE: ThisguidefocusesoninsideoutUFmembraneconfigurationsonly.


ULTRAFILTRATION APPLICATIONS

Ultrafiltration(UF)isusedformanyapplicationsrequiringthereductionofsuspendedsolidsincludingparticles,colloids,cysts,bacteriaandvirusesbymechinicalmeans.Typicalapplicationsinclude:

Surface Water TreatmentUFisusedaspartofamulti-barriersurfacewatertreatmentforthereductionof:•Turbidity•Finesiltnoteasilyfilteredbyconventionalmediafilters•TotalOxidizableCarbon(TOC)associatedwithhighmolecularweightorganics•Cystsnoteasilyfilteredbyconventionalmediafiltersorinactivatedbychlorine

Well Water Under the Influence of Surface WaterUFcanbeusedtotreatshallowwellsformechanicalreductionof:•Turbidity•Finesiltnoteasilyfilteredbyconventionalmediafilters•TotalOxidizableCarbon(TOC)associatedwithhighmolecularweightorganics•Cyststhatarenoteasilyfilteredbyconventionalmediafiltersorinactivatedbychlorine

Pretreatment of Reverse Osmosis (RO) Feed WaterPretreatingROfeedwaterwithUFincreasesmembranelifeandlowersoperatingcosts:•LowersfeedwaterSiltDensityIndex(SDI)–byremovingturbidityandcolloids•Removessuspendedsolidsthat“breakthrough”conventionalpressurefilters•Increasescartridgefilterlife•ReducesbiofoulingbyreductionofTotalOxidizableCarbon(TOC)andbacteriabymechanicalmeans

Prefiltration of Water Feeding Sensitive EquipmentUFcanbeinstalledpriortoone-time-usespecializedfiltersandothersensitiveequipmenttoloweroperating costs: •Foodservice–prefiltrationoftasteandodorandcystfiltersgreatlyextendsservicelife•Laboratory,pharmaceutical,lifescience–extendsthelifeofdisposablemembranefilters

Postfiltering High Purity Water in Special ApplicationsUFcanbeinstalledafteranRO/deionizedwater(DI)systemtoimprovethequalityoftheultrapurewaterandloweroperatingcosts:•Pharmaceutical,lifescience–installinthepurewaterrecirculationlooptoextendthelifeofdisposablepoint-of-usefilters

•Ultrapurewater–installinthepurewaterrecirculationlooptoreducebacteria,TOC;extends thelifeofdisposablepoint-of-usefilters

Point-of-Entry Filtration for Residential and Commercial InstallationsInstalledaspartofmulti-barriersystem,UFoffers“peaceofmind”byprovidinganadditionalbarrieronpotablewatersuppliesagainstcompromisestothewatersystem,reducing:•Cysts •Bacteria•Turbidity •Viruses

Industrial and Municipal Waste WaterUFforwastewatertreatmentisbeyondthescopeofthisguide.

CAUTION:Onlysystemsthatarethirdpartycertifiedaswaterpurifiers,andmeetstateandlocalregulations,canbeusedtopurifyunsafedrinkingwatersupplies.

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WATER QUALITY BASICSWater Sources

Watersmaybecategorizedbytheirsource–groundwaterorsurfacewater.Thisclassificationdefinesthebasichistoryofthefeedwater,anddeterminesthelikelytypeandlevelofitsimpurities–andthereforeitsquality.Evenrainwatercontainssomeimpuritiesfromtheatmosphere.Surfacewaterisdrawnfromlakes,ponds,streams,andrivers.Itgenerallycontainsagreaterdegreeoforganicmaterialthangroundwatercausedmainlybydecayingvegetation.Surfacewaterisalsolikelytocontainsubstancesfromindustrialdischarge,agriculturalrunoff,andotherhumanactivities.Highconcentrationsofmicrobessuchasbacteria,viruses,andcystsaremorecommoninsurfacewaterthangroundwater.Groundwater,whichisdrawnfromwells,comesfromrainwaterthathaspercolatedthroughtheearthandcollectedinundergroundaquifers.Waterwellsvarygreatlyindepth,butgenerallydeeperwellshavelessorganicmaterialduetothenaturalfiltrationofthewaterpercolatingthroughtheground.Groundwatermayalsobedischargedtothesurfacefromnaturalsprings.Groundwatertendstohavehigherconcentrationsofinorganiccompounds.Groundwaterinshallowand/ordisruptedlocationsmaybeconsideredgroundwaterundertheinfluenceofsurfacewater,andhavesubstancesnormallyassociatedwithsurfacewatersupplies.Forexample,shallowwellwatermaycontainnitratesand/orcoliformbacteriafromnearbyagriculturalactivity.Shallowwellwater,likesurfacewater,maybeturbid(i.e.hazyinappearanceduetoparticlesfloatingwithin).

Seasonal VariationsSurfacewatertendstochangeinqualityduetoseasonalandweatherinfluences.Forexample,algaebloomsinlakesandriversmayoccurinlatesummer.Lakesandreservoirsinareaswithsubstantialtemperaturevariation“turnover”twiceayear,whichcandrasticallychangethewatercomposition.Snowmeltandspringrainrunoffaddmoresuspendedsolidsandimpuritiestorivers,andtheirconcentrationincreasesduringdryperiods.Evenmunicipallytreatedsurfacewaterqualitywillvarywiththeseasons.Asaresult,membranefoulingmaybemoresignificantinsomemonthsversusothers.

Water ImpuritiesWatermaycontainawiderangeofforeignmaterial.Mattermaybedissolvedorsuspendedinwater(presentassolutesorparticles).Solutesareatoms,moleculesorcompoundsthatcompletelydissolveinwater(i.e.completelyhydrated).Examplesincludeinorganicsaltionssuchassodium,calcium,chloridesandsulfates,andorganicmoleculeslikesugarsandtannicacid.Particulate matter is that material that is not dissolved and remains a discrete particle suspended in water.Examplesincludeclays,sand,dust,andsolutesthatreachtheirsaturationpointandprecipitateoutofsolution.Dissolvedorganicmatterincludesawiderangeofmaterialfromverysmalltolargemolecules. Examples of naturally occurring organics include tannins, lignin, humic and fulvic acids, proteins and thestarchesandcelluloseofplantcellwalls.Surfacewateroftencontainssubstantiallymoreorganicmatterthangroundwater.LargerorganicmoleculesmaybepartiallyremovedbyUFmembranes.Colloidsarechargedparticlestypicallymadeupofacombinationofmoleculesbothorganicandinorganic.Theyareheldinsuspensionbyelectrochemicalforcesthatputtheminacategorybetweenatruesoluteandsuspendedparticles.Theyaregenerallyviewedasverysmallparticles.Colloidsinwaterincludesilicaandiron(incertainforms).Virtuallyallparticulatematter(includingcolloids)largerthanthemembraneporesizewillberemovedbytheUFmembrane.Sincethesuspendedmaterialsaretrappedbythemembrane,theyconcentrateonthesurfaceofthemembraneandhavethepotentialtofoulit.Duetotheelectricalchargeassociatedwithcolloids,theycanbeespeciallyproblematicwithrespecttofouling.Microbesinwaterincludeviruses,bacteria,andsingle-cellprotozoa.Virusesareverysmallandcannotreproduceifsuspendedinwater–theyrequireahostorganism.UFremovesmostviruses, dependingontheporesizeandtypeofvirus.Bacteriaarelargerthanvirusesandmanydifferenttypesmaybepresentinwater.Bacteriareproduceinwaterespeciallyinstagnantwater.Mosttypesofbacteriaareharmlesstohumans,butsomebacteriatypes,especiallyE. coli fromanimalwaste,maycauseillness.ProtozoaincludemanyspeciesincludingGiardia Lamblia and Cryptosporidium cysts whichareknowntocausegastrointestinalillness.


Water Analysis Anunderstandingofthefeedwatersource,includingpriortreatmentandanalysisofthefeedwater,isessentialtodeterminethebestconfigurationandoperationalsettingsforaUFsystem.Ataminimum,thefollowingtestsarerecommended:SiltDensityIndex(SDI)–AnSDItestmustberunon-site.Thistestentailsrunningwaterthrougha0.45umfilterataconstantpressureandrecordingthereductioninflowratebymeasuringthetimeittakestofilla500mLbeakerinitiallyandthenafter5,10and15minutesofcontinuousflow.Thistestprovidesagoodindicationofthefoulingtendencyofthewaterduetosuspendedsolidsandcolloids.TotalOxidizableCarbon(TOC)–OrganicmattertypicallyismeasuredasTotalOxidizableCarbon(TOC),alsocalledTotalOrgaincCarbon.TOCisatypicalmeasurementforcarbonaceousmaterialinwater.Turbidity–Turbidityisameasureofhazinessorlackofclarityinwater,causedbylightdiffraction.Althoughnottechnicallythesameassuspendedparticulatematter,particulatesusuallycauseturbidity.TotalandDissolvedIron(TDI)–Totalironmeasuresbothdissolved(ferrousorclearwater)andoxidized(ferricorprecipitated)formsofiron.UFmayremoveferricironwhichmayfoultheUFmembrane.

Otherteststhatmaybehelpfulinclude:DissolvedOrganicCarbon(DOC)–AsubsetofTOC,DOCmeasuresorganicmatterthatwillpassthroughananalyticalmembranetoremoveparticulatematterbeforetesting.Tannins,Lignin,HumicAcid,andFulvicAcid–Oftenfoundinsurfacewatersandrequirespecializedtests.Allmaycontributetocolor.TotalSilica–Measuresallsilicainthewater,includingdissolvedandcolloidalforms.

FEED WATER QUALITY AND PRETREATMENT REQUIREMENTSTheperformanceofanymembranesystemishighlydependentonfeedwaterquality.Itinfluencesmembranelife,flushingfrequency,cleaningfrequency,recommendedflowrate,andfiltratequality.Itisvirtuallyimpossibletopredictthepreciseperformanceofasystemduetothewiderangeoffoulantsthatcanbepresentinwatersupplies,andbecausewatersuppliesvaryfromseasontoseasonandevendaytoday.However,apilotstudyisthemosteffectivewaytodeterminethelong-termperformanceofamembranesystem.Itisimportantthatthepilotstudyincludetheexpectedextremesinfeedwaterqualityifitistoprovidemeaningfulresults.Wewillconsiderseveral“typical”watersupplieswhenofferingguidelinesforUFsystemsapplicationsinthisguide.Therecommendedoperatingconditions,systemconfiguration,suggestedpretreatmentequipment,andexpectedperformancearealldependentuponinitialfeedwaterquality.

General Feed Water•Temperature–34°to104°F.•pH–3to10.•Iron–Dissolvedironwillnotfoulthemembranenorwillthemembraneremovedissolvediron.Lowconcentrationsofprecipitatedironcanberemovedbutmaycausefoulingatconcentrationsabove1mg/l.

•Chlorine–4.0mg/lcontinuous(200.0mg/lshortterm).•Ozone–0.0mg/l.•Turbidity–5.0NTUcontinuous(20.0NTUintermittent).•Silicone/SiliconeLubricants–Mustnotcomeincontactwithmembraneinconcentrationsthatcausefouling.

•OrganicSolvents/ChlorinatedSolvents–Mustnotcomeincontactwithmembrane.•Polyelectrolytes–Mustnotcomeincontactwithmembraneinconcentrationsthatcausefouling.•FreeOilandGrease–Mustnotcomeincontactwithmembraneinconcentrationsthatcausefouling.

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Surface Water (Municipally Pretreated)•Suggestedminimumpretreatment: –Flocculation,settling/clarificationandfiltration(bymunicipality). –Disinfection(bymunicipality). –200-micronprefilter(optional).

•Chlorine–<4.0mg/l.•Turbidity–<5.0NTU.•TOC–<2.0mg/l.•SDI15–<6.67.•Metals(Fe,Mn,Cu,etc.)–<1.0mg/l.

Surface Water (Private Multi-Barrier System)•Suggestedminimumpretreatment: –In-linecoagulationandfiltrationwithmultimediafilter. –Disinfectionwithchlorine. –200-micronprefilter(optional).

•Chlorine–>2.0mg/l,<4.0mg/l.•Turbidity–<5.0NTU.•TOC–<10.0mg/l.•SDI5–<20.0.•Metals(Fe,Mn,Cu,etc.)–<1.0mg/l.CAUTION:DosageofcoagulantmustbecontrolledtopreventfoulingoftheUFmembranes.

Well Water (Municipally Treated Deep Well)•Suggestedminimumpretreatment: –Ironremovalfiltration(ifironover1mg/l). –Disinfection(bymunicipality). –200-micronprefilter(optional).

•Chlorine–<4.0mg/l.•Turbidity–<5.0NTU.•TOC–<2.0mg/l.•SDI15–<6.67•Metals(Fe,Mn,Cu,etc.)–<1mg/l

Well Water (Private Deep Well > 100 ft.)•Suggestedminimumpretreatment:–Ironremovalfiltration(ifironover1mg/l)–Disinfection–optional–200-micronprefilter–optional•Chlorine–<4.0mg/l•Turbidity–<5.0NTU•TOC–<2.0mg/l•SDI15–<6.67•Metals(Fe,Mn,Cu,etc.)–<1mg/l

NOTE:Wellsundertheinfluenceofsurfacewater(suchasthoselessthan100ft.deep)mayrequiretreatmentsimilartosurfacewater.


Pure Water (UF used to post-treat high purity RO/DI water)•Suggestedminimumpretreatment: –RO –MixedbedDIorContinuousDIsystem

•Chlorine–0.0mg/l•Turbidity–<0.1NTU•TOC–<1.0mg/l•SDI15–<1•Metals(Fe,Mn,Cu,etc.)–<0.1mg/lNOTE:ThefeedwaterlimitsshownareforwaterenteringtheUFmembranes(i.e.afteranyprefiltration,chemicaladdition,etc).

FILTERED WATER QUALITY

Thequalityoffiltrate(filteredwater)willvarydependinguponfeedwaterquality,operatingconditionsandtheconditionofthemembrane(s).Thefiltrationperformanceshownbelowrepresentstypicalresults.Pilottestingisrequiredtodeterminesite-specificresults.

Typical Filtered Water Quality•Particleremoval–99%+removalefficiencyforparticles1micronandlarger•Turbidity–<5NTU•Cystreduction–99.95%•Bacteriareduction–4to6logreduction(astestedwithKlebsiellaterrigena)•Virusreduction–1to4logreduction(astestedwithMS2coliphage)•SDI15–<2

SYSTEM SIZING

Ultrafiltrationsystemshavepeakflowandcontinuousflowratings.Thepeakflowratingisbasedbothonstandardoperatingconditionsandmembranesthatarein“asnew”condition(i.e.notfouledordegraded).Thepeakflowratingistypicallyusedtosizesystemsforresidentialapplications.Flowsinresidentialapplicationsareintermittent,andthereareveryfewtimesthathomesactuallyexperiencehighflowrates.Forexample,Aquacraft,Inc.WaterEngineeringandManagementpreparedastudyforWQAin2001toidentifyindoorflowratedemandsin1,188homesacrossvariousregionsoftheU.S.andCanada.Findings included:•70%ofallflowswere2.5gpmorless•92%ofallflowswere5gpmorless•99%ofallflowswere7.5gpmorless•99.9%ofallflowswere10gpmorlessCommercialapplications,however,aremorelikelytoexperiencesustainedperiodsofcontinuous flow.Systemsforcommercialapplicationsshouldbesizedbasedonthecontinuousflowratingof themembrane.

Membrane Flux RatesMembranemanufacturerstypicallyrecommendmembraneflowratesintermsofspecificfluxrates(i.e.gallonsperdaypersquarefootofmembranesurface[gfd]).Theserecommendedfluxratesshouldbeusedforsystemsizingguidance.However,fluxrates/systemflowsmayneedtobeadjustedbasedonlocaloperatingconditionsandfeedwaterquality.Pilotstudiesarethebestwaytodetermineanappropriatefluxrate. (Continued on next page)

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Membrane Flux Rates (continued)

Recommendedfluxratesforvariousfeedwatersources/qualityareshowninthetablebelow. Toobtainrecommendedflowrates,multiplythefluxratetimesthemembranearea.(Seemembranedatasheets).

NOTE:MetalsincludeFe,Mn,Cu,etc.

Temperature Correction FactorUFmembranecapacityisdependentupontemperature.Membraneflowdropsabout2%to3%foreach1°C(1.8°F)decreaseinfeedwatertemperature.Thislossinflowcanbecounteractedbyincreasingthepressure,providedthatmaximumtrans-membranepressureisnotexceeded.Thistable(seeright)showsthelossinflowassociatedwithfeedwatertemperaturesbelowstandardtestconditions25°C(77°F).Thistableassumesthattrans-membranepressureisheldconstantandonlywatertemperature ischanged.

OPERATING GUIDELINES

TEMPERATURE CORRECTION FACTOR°C °F

25 77 122.5 72.5 0.9320 68 0.86

17.5 63.5 0.8015 59 0.74

12.5 54.5 0.6910 50 0.647.5 45.5 0.605 41 0.55

2.5 36.5 0.51

Feed Water QualityRefertotheFeedWatersectionofthisguide(pages7-9).IftheUFisinstalledaspartofamulti-barriersystem,thewaterqualityshouldbecheckedattheinlettotheUFmembranes(i.e.afterallchemicaladditionandprefiltration).PrefiltrationA200-micronprefilter/strainerisrecommended.Membrane PressureFollowtheguidelinesinthemembranedatasheetwithregardtoallowabletrans-membranepressure.Scaling/FoulingPreventprecipitationintheUFsystem(e.g.Fe,Mn,CaCO3).Water HammerPreventionofwaterhammerisrequiredtoavoidmembranedamage.Protection from Abrupt Variations in TemperatureAvoidabruptvariationsintemperature.Themaximumoperatingtemperatureis40°C(104°F). Temperatureequalizationshouldberealizedslowly.Protection from Abrasive MaterialsThemembranemustbeprotectedfromabrasivematerials(e.g.machiningshavings,constructiondebris)whichcancauseirreversibledamagetothemembrane.Silicone or Lubricants Containing SiliconeLubricants/materialscontainingsiliconecancauseirreversibleblockageofthemembraneandmustnotcontactthemembranesurface.Useglycerinasalubricantforseals,o-rings,etc.

OPERATING CONDITION UNITS FLUX RATE TURBIDITY (NTU) SDI METALS (mg/l)

TOC (mg/l)

Peak/Initial (@ 25°C) gfd 280 < 0.1 < 1 < 0.1 < 1

Pure Water gfd 180 < 0.1 < 1 < 0.1 < 1

Well Water gfd 85 < 1 < 6.67 < 1 < 2

Surface Water gfd 35 < 20 < 20 < 1 < 10


SYSTEM CONFIGURATIONSAutomatic Flushing Operation Systemsmaybeconfiguredtoflushinoneoracombinationofthreebasicmodes.Thetablebelowdescribesthevalvesequencingrequired.

Forward-flush –Thedrainvalveisopenedsothattheflowthroughtheboreofthefibersissignificantly increased.Retainedsolidsareflushedfromthemembranesurfaceduetothevelocityofthewater.Back-flush – Thedrainvalveisopened,thefeedwaterisshutoff,andthefiltrateisallowedtoreverseflowthroughthemembrane.This“lifts”retainedsolidsfromthemembranesurface,flushingthemtodrain.Thefiltrateusedforback-flushingcanbeprovidedbyastoragetankorbyotherUFmembranesthatremaininservice.Combined flush – Combinesbothback-flushandforward-flushsimultaneously.Thisnormallyoccursbyopeningthedrainvalve,whilethefeedwatersupplyremainsopenandback-flushwaterissuppliedbyothermembranesoranexternalsource.

Flush Valve SequencingSYSTEM

FLUSH TYPE CYCLE INLET VALVE DRAIN VALVE FILTRATE VALVE NOTES

Forward-Flush Only Forward-Flush None Open None Filtrate check valve required if

storage tank is used

Back-Flush Only Back-Flush Closed Open NoneBack-flush water provided by

storage tank or other membranes (no filtrate check valve)

Sequential Back- Then

Forward-Flush

Back-Flush Closed Open Open (if used)

If back-flush provided by tank and filtrate valve is not used,

then backflow prevention during forward-flush is requiredForward-Flush Open Open Closed

(if used)Combined

Forward- and Back-Flush

Combined Forward- and Back-Flush None Open None Back-flush water provided by

other membranes

Therequiredflushfrequencyisdependentuponlocaloperatingconditionsandmayrequireadjustmentafterinstallation.Furthermore,feedwaterqualitymayvaryseasonallyorwhenalternatewatersuppliesareused.Adjustmentstoflushingfrequencymayberequiredtoaccommodatechangesinfeedwaterquality.

Initial Recommended Flushing Parameters by Water Source and Treatment

WATER SOURCE FORWARD-FLUSH BACK-FLUSH

SEQUENTIAL BACK- THEN

FORWARD-FLUSH

COMBINED FORWARD- AND

BACK-FLUSH

FLUSH FREQUENCY (GALLONS

THROUGHOUT)

Surface Water Municipally Treated Minimum Minimum Recommended Recommended 100

Surface Water Private Multi-Barrier

Treatment

Not Recommended

Not Recommended Recommended Minimum 50

Well Municipally Treated Minimum Minimum Recommended Recommended 200

Well Private Minimum Minimum Recommended Recommended 100

Pure Water Recommended Recommended Recommended Recommended 500

NOTE: Themaximumrecommendedtimebetweenflushcyclesis24hours.Wellsthatareundertheinfluenceofsurfacewater(suchasthoselessthan100ftdeep)mayrequiretreatmentsimilartosurfacewater.

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Storage TanksSomesystemsmayutilizeasingleUFmembrane,whileothersmayusemultiplemembranestoprovidetherequiredflowrateandfeatures.Systemsmaybeconfiguredwithafiltratestoragetankorconfiguredasadirectfeedsystemwithnofiltratestoragetank.Onsomesystems,itmaybebeneficialtoprovideastoragetanktomaintainwaterpressureduringthe flushcycles,toprovidewaterforback-flushingoftheUFmembrane,andtoprovideadditionalwaterpressureduringshortperiodsofhighflowdemand.Thestoragetankmayalsobeusedinback-flushing systemstostorefiltratefortheflushcycle.Thefiltratestoragetankcanbeanatmospherictankoraclosedhydropneumatictank.Theadvantages oftheclosedhydropneumatictankisthatthewaterisnotexposedtoairborneimpuritiesandnopumpisneededtorepressurizethewater.NOTE:Forthepurposesofthisguide,itisassumedthatthestoragetankisaclosedhydropneumatictankunlessotherwisespecified.Thefigurebelowshowsasystemwithastoragetankusedformaintainingevenwaterpressure,butnotusedforflushing.


SHIPPING AND HANDLINGCareful Transport and Handling

Mechanicaldamage/ruptureofthemembraneshellandconnectionscanresultifthemembranesaredroppedorcollide.Therefore,membraneunitsmustbehandledwithcareatalltimesduringtransportation,installation,andstartup.

StorageMembranesshouldbestoredinadrysettingwithnormalventilation,removedfromanydirectsunlight,heatorignitionsources.Storagetemperatureshouldbebetween4°and30°C(40°and86°F).Membranemodulesshouldnotbesubjectedtoanyfreezingconditions.Topreventdehydrationandcontrolbacterialgrowth,membranesaresaturatedwithawater/glycerin/sodiumbisulfitesolution(74.75%water,25%glycerin,0.25%sodiumbisulfite)andsealedinplasticbagsorindividualmembranehousingspriortoshipment.Sealedmembranes(inoriginalpackaging)canbestoredforuptoeightmonthsafterdeliveryifstoredbetweenatemperatureof4°-30°C(40°and86°F).Whenexceedingeightmonthsofstorage,theindicatedsolutionmustberefreshed.ROorDIwaterisrecommendedforthesaturationsolution.Beforestorage,membranemodulesshouldbesealedinplasticbags.Ifprocessedaccordingly,membranemodulescanbestoredforanothertwomonthsbeforethesolutionwouldhavetoberefreshed.

SYSTEM STARTUP GUIDELINESPiping

SystemandinstallationpipingshouldbecleanedbeforetheUFsystemisstartedsothatnoimpurities, abrasivematerials,oroilymaterialsarewashedintothemembranes.Pipingmustbepurgedofairtopreventwaterhammerwhichcandamagethesystem.

FlushingFlushthemembranetoremovethemembranestoragesolutionpriortoplacingtheUFsysteminservice.

System DisinfectionThesystemshouldbedisinfectedafterflushingbutpriortouse.Seethisguide’sdisinfection/sanitizingguidelines(pages14-15).

MEMBRANE RINSINGTopreventdehydrationandbiologicalgrowth,membranesareshippedandstoredinawater/glycerin/sodiumbisulfitesolution.Thefollowing3-cyclemembranerinseproceduremustbeperformedinorder to remove the storage solution prior to use:

Rinse Cycle 1A.Slowlyfilltheinflowsideofthesystemwithuntreatedwaterinordertoavoidwaterhammer.B.StartaForward-FlushCycle(directionofflowfromthebottomtothetop)atareducedflushflow

rateforaminimumofthreeminutesorlongerifrequiredtopurgeallairfromthesystem(observethedrainflowforair).

C.Operatetheunitinthenormalfiltrationmodeatalowflowrate—providearangeofflow2.0-2.5GPM—foraminimumof20minutes.Makesurethefiltrateoutletisopenandallwaterproducedisdischargedtothedrain.

D.Ifastoragetankisused,makesurethatitisdrainedcompletelyafterthefirstrinsecycle.

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Rinse Cycle 2A.Operatetheunitinthenormalfiltrationmodeatalowflowrate—providearangeofflow2.0-2.5

GPM—for20minutes.Makesurethefiltrateoutletisopenandallwaterproducedisdischargedtothedrain.

B.Initiateastandardflushcycle(whichmayincorporateback-andforward-flushcycles).Ensure thatthesystemflushesforaminimumof60seconds,whichmayrequiretwoflushcyclesinitiatedback-to-back.

C.Ifastoragetankisused,makesureitisdrainedcompletelyafterthesecondrinsecycle.

Rinse Cycle 3A.Operatetheunitinthenormalfiltrationmodeatalowflowrate—providearangeofflow2.0-2.5

GPM—for20minutes.Makesurethefiltrateoutletisopenandallwaterproducedisdischargedtothedrain.

B.Initiateastandardflushcycle(whichmayincorporateback-andforward-flushcycles).Ensure thesystemflushesforaminimumof60seconds,whichmayrequiretwoflushcyclesinitiated back-to-back.

C.Ifastoragetankisused,makesureitisdrainedcompletelyafterthethirdrinsecycle.D.Placethesysteminthenormalfiltrationmodeandfillthestoragetank,ifequipped.NOTE: Thisinformationisprovidedasageneralguideline.Alwaysrefertoaspecificsystem’soperatingandmaintenancemanualfordetailedprocedures.

SYSTEM SANITIZINGTheunitshouldbesanitized/disinfectedaftertheinitialstartuprinsingprocedureorincaseofbiologicalfouling.CAUTION: Sodiumhypochlorite(bleach)isusedfordisinfection.Theusershouldacquaintthemselveswiththeappropriatesafetyprecautionsforstorageandhandlingofthechemicalsbeingused.Useonlysodiumhypochlorite.Donotusebleachescontaininganyothercompounds.

Procedureifacleaningsystemisavailable:1. Prepareasolutioncontaining100mg/l(asCl2)ofchlorineusingUFfiltratewater.2. Removetheinlet,outlet,anddrainplumbingfromthemembrane(s).Connectthecleaningsystem

pumpoutlettothemembranefeedpiping.Connectthedrainandfiltratetothecleaningtank.3. Recirculatethesolutionforfiveminutes,returningthefiltrateanddraintothecleaningtank.4. Letthesystemsoakforonehour.5. Emptythecleaningtank.6. Refillthecleaningtankwithcleanwater(UFfiltrateifavailable).7. Pumpthewaterinthetankthroughthesystemwithbothfiltrateanddrainlinesdirectedtothedrain.8. Reconnectthepipingsystemfornormaloperation.9. Operatetheunitinthenormalfiltrationmodefortenminutes.Makesurethefiltrateoutletisopen

andallwaterproducedisdischargedtothedrain.10. Initiateastandardflushcycle(whichmayincorporatebothback-andforward-flushcycles).11. Ifastoragetankisused,makesureitisdrainedcompletelyaftertheflushcycle.12. Operatetheunitinthenormalfiltrationmodefortenminutes.Makesurethefiltrateoutletisopen

andallwaterproducedisdischargedtothedrain.13. Initiateastandardflushcycle(whichmayincorporatebothback-andforward-flushcycles).14. Ifastoragetankisused,makesureitisdrainedcompletelyaftertheflushcycle.15. Placethesysteminthenormalfiltrationmodeandfillthestoragetank(ifequipped).16. Samplethefiltratebycheckingthebacteriologicalquality.Iftestresultsarenotsatisfactory,

repeatthedisinfectionprocedure.NOTE: RefertotheCleaningSystemSchematicinthemembranecleaningsectionofthisguide(page17).


ProcedureifacleaningsystemisNOTavailable:1. Prepareasolutioncontaining100mg/l(asCl2)ofchlorineusingUFfiltratewater.2. Removetheinlet,outlet,anddrainplumbingfromthemembrane(s).3. Ifthesystemisfurnishedwithacartridgefilter(s)removethefilterelements.4. Fillthemembranehousing(s)andfiltersump(s)withthechlorinesolution.5. Letthesystemsoakforonehour.6. Reconnectthepipingsystemfornormaloperation.Donotinstallthefilterelementsyet.7. Operatetheunitinthenormalfiltrationmodeforfiveminutes.Makesurethefiltrateoutletis

openandallwaterproducedisdischargedtothedrain.8. Stoptheunitandreinstallthecartridgefilter(s)ifapplicable.9. Operatetheunitinthenormalfiltrationmodeforanadditionalfiveminutes.Makesurethefiltrate

outletisopenandallwaterproducedisdischargedtothedrain.10. Initiateastandardflushcycle(whichmayincorporatebothback-andforward-flushcycles).11. Ifastoragetankisused,makesureitisdrainedcompletelyaftertheflushcycle.12. Operatetheunitinthenormalfiltrationmodefortenminutes.Makesurethefiltrateoutletisopen

andallwaterproducedisdischargedtothedrain.13. Initiateastandardflushcycle(whichmayincorporatebothback-andforward-flushcycles).14. Ifastoragetankisused,makesureitisdrainedcompletelyaftertheflushcycle.15. Placethesysteminthenormalfiltrationmodeandfillthestoragetank(ifequipped).16. Samplethefiltratebycheckingthebacteriologicalquality.Ifthetestresultsarenotsatisfactory,

repeatthedisinfectionprocedure.Note:Thisinformationisprovidedasageneralguideline.Alwaysrefertoaspecificsystem’soperatingand maintenancemanualfordetailedprocedures.

MEMBRANE INTEGRITY TESTAllmembraneelementsarefactorytestedandpassintegritystandardspriortoshipment.However,afullsystemintegritytestshouldbeconducteduponstartupandperformedroutinelythereafter(onceperyearminimum).Theintegrityisusedtocheckfor: –Internalleaks,suchascutormisalignedo-rings –DamagedmembranesThepreferredintegritytestisapressuredecaytest.Thistestinvolvestheapplicationofairpressuretothemembranewhenitisfully“wet-out”(i.e.theporesarefullofwater,whichistheconditionofthemembranewhenithasbeenproperlyflushedafterstartup).Theamountofpressurelossismeasuredoverasetperiodoftime.Ifthepressuredeclinestoofast,thisindicatesthatthereisasealleakinthesystemormembranefiberdamage.

General Test Information•Thetestrequiresthatthemembranebefully“wet-out”(i.e.allporesfullofwater).•Themembraneassemblyshouldbedrainedofallexcesswater.•Thistestdoesnotrequirethevisualdetectionofabubble;insteaditmeasuresthelossofpressureorvacuumovertimeviaagauge.

•Acertainamountofpressurelosswilloccurinanintactsystemfromsimplediffusionofairthroughthewatertrappedinthemembranepores(“baselinedecay”).Butahigherpressurelosswilloccurfrommembraneflawsorbrokenseals.

•Topreventcontamination,useeitheracleanairsourceora0.2-micronfilterontheairsource.Equipment

•Pressurizedairsource(~20psig,3+scfmcapacitywithpressureregulator,typicallyasmallportableairtankorportablecompressor.

•Pressuregauge(0-20or0-30psig)withaccuracyto0.1psi.•Positiveshutoffvalve(abubble-tightballvalve)toisolatetheUFmembraneinlet,andonetoisolatetheairsource.

•Stopwatchorwatchwithasecondhand.

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Procedure1. Ensurethemembraneisfully“wet-out”;operatethesystem

atitsnormalflowrateforseveralminutesbyopeningthenearesttapdownstream.

2. Drainthefeedsideofthemembranefor10-15minutes.Ifpossible,drainthefiltratesideofthesystemfor10-15minutes.

3. Close supply and drain valves to isolate the feed side of the system.Thefiltratesideofthemembraneshouldbeopen toatmosphere.

4. Graduallypressurizethefeedsideofthefibersto15psig.NOTE: Donotoverpressurize;thiswillforcethewateroutoftheporesandthemembranewillnolongerbe“wet-out”,resultinginafalsefailure.

5. Closethevalvebetweentheairsourceandgauge;simultaneouslybeginmeasuringtime.

6. Notethepressureat60,120,and180secondsandrecordit.7. Relieveairpressureslowlybeforedisconnectingtheairlines.8. Ifsystempressureholdsbetween14.5and15.0psigafter

twominutes,thesystemintegrityisgoodandthuspassesthetest.

9. Ifsystempressureis14.5psigorlessaftertwominutes,checkconnectionsandplumbingforpossibleairleaks.

10. Ifsystempressuredropstolessthan14.5psigaftertwominutes,theo-ringsealmaybepinched,defective,orabsent,orthemembraneelementmaybedamaged.

NOTE: Theflushsolenoidmayneedtoberemovedandthelinecappedofftoensureagoodairseal.

MEMBRANE CLEANINGMembranecleaningisrequiredwhenthesurfaceofthemembraneandmembraneporesbecomefouled.Thisismostoftendetectedbyalossofflowrate.UFmembranesshouldbemaintainedinacleancondition,unfouledbyparticulatematter,precipitates,orbiologicalgrowth.

Monitoring Membrane Performance for FoulingMembranesareconsideredfouledif“normalized”filtrateflowdeclinesmorethan10percentwithin24hourswhenmeasuredimmediatelyafteraflushcycle.Normalizingthefiltrateflowisrequiredtoaccountforthedifferencesinfeedwatertemperatureandtrans-membranepressure.

Normalizing Flow DataNormalizethepermeateflowdataasfollows:•Operatethesystematthesametrans-membranepressurewhencomparingtwodatapoints.Ensurethepressuredropassociatedwithothersystemcomponentsisnotincludedinthedata.

•Correctfortemperaturedifferencesusingthetemperaturecorrectionfactor.

Exampleofasimplifiedmethodtonormalizeflowdata:•Day1filtrateflow=2.5gpm,watertemperature=20°C(68°F),trans-membranepressure=8psid•Day2filtrateflow=2.0gpm,watertemperature=17.5°C(63.5°F),trans-membranepressure=7psid•Day2datanormalizedtoDay1conditions: –2.0x8/7(pressure)x0.86/0.80(temperature)=2.46gpm –Therefore,thenormalizedfluxlossis2%

Drain

FlowControl

PressureGauge

Inlet

Filtr

ateIntegrity Test

Simplified Diagram

UFMembrane

Air Tank/Air Supply


TankTank

Drain

UFMembrane

FiltrateFiltrate

PumpPump

Cleaning SystemSchematic

FeedWaterFeed

Water

Before CleaningBeforecleaningthemembrane(s),makesurethemembrane(s)is/arebeingproperlyflushedduringnormalautomaticflushcycles.Ensurethatthereisadequatewaterpressureduringalloftheflushcyclesandthatthedesignflushflowsareachieved.Thenimplementseveralmanualflushcyclestoseeifthenormalizedflowisrestored.Ifflowcanberestoredbyadditionalflushcycles,itmaybebeneficialtoincreasethefrequencyofthetimedurationforautomaticflushcycles.

Cleaning Procedure1. Ifflushingdoesnotrestoremembraneflow/flux,cleanasfollows:2. Performtwocomplete,consecutive,automaticflushcycles.

Setupcleaningsystemasshownintheschematic.NOTE: Cleaningsystemcomponentsmustbecompatiblewiththecleaningchemicals.

3. Preparethecleaningsolutionperthetableatthebottomofthispage.Selectingthecleaningsolutionisdependentuponthetypeoffoulant,whichwilldependuponfeedwatersourceandquality.Somegeneralguidelines:

A.Sourceofwater •Ifthesourcewaterissurfacewater,thefoulingwilltendtobeorganic-based.

•Ifthesourcewaterisgroundwater,foulingtendstobeinorganic-based.

B.Inletwateranalysis •IftheinletwaterhasrelativelyhighlevelsofTOC,DOC, ortannin,focusonorganiccleaningmethods.

•Iftheinletwaterhasrelativelyhighlevelsofiron,manganese, or hardness, focus on inorganic cleaning methods.

4. Makeupthecleaningsolutionperthetablebelow.5. Connectcleaningsystemhosestothemembranemodule(s)asshownintheschematic.6. Startthepumpandcirculatethecleaningsolutionthroughthemembrane(s)inthenormalflow

directionatthenormalforward-flushflowrate.Returndrainandfiltratehosestothecleaningtank.7. Circulatethecleaningsolutionthroughthemembranefor15minutes.8. Stopthepumpandallowthesystemtosoakfor15minutes.9. Repeattherecirculate/soakcyclesuntilnoadditionalfoulantsarebeingremoved.NOTE: Observecleaningtankwaterclarityanddump/replacethecleaningsolutionifitisevidentthatthecleaningsolutionisfouled.MeasurethecleaningtankwaterpH,addingacidifrequiredtomaintainthepHbetween1to3,orcausticifrequiredtomaintainpHbetween11and13.

10. Flushthemembranes.(SeeMembraneFlushing).11. Disinfectthemembranes.(SeeDisinfection/Sanitizing).12. Determinethenormalizedmembraneflow/flux.13. Repeatasneeded.NOTE: Thisinformationisprovidedasageneralguideline.Alwaysrefertoaspecificsystem’soperatingandmaintenancemanualforthedetailedprocedure.

1. Usewaterwith50%NaOH.2. Use H2O25%solution.3. UseHCI(30%HCl).4. Usehouseholdorcommercial-gradebleachwithno

fragrancesoradditives.5. Usefood-gradecitricacid.CAUTION: Cleaningsystemwasteshouldbetreatedtocomplywithlocalregulations(pHneutralized)beforethespentcleaningsolutionisdischargedtodrain.

CLEANING SOLUTION

CLEANER FOULANT FINAL pH OR CONC.

Sodium Hydroxide Solution (NaOH) Organics 13

Bleach Solution (NaOCl)

Organics/ Biological 200 mg/l

Hydrogen Peroxide Solution (H2O2)

Organics/Biological 500 mg/l

Hydrochloric Acid Solution (HCl) Hardness 1

Citric Acid Iron 1

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MEMBRANE STORAGE AFTER USEAfterinitialuse,themembrane(s)needtobekeptwetatalltimes.Toavoidbiologicalgrowthduringshutdownsorstorage,wetmembranesshouldbetreatedwithacompatiblebiocide.

Downtimeupto24hours–NomeasuresrequiredDowntime1to7days–Automaticflushing

Systemsequippedwithautomatictime-basedflushsystems(withavailablefeedwater)cancontinuetoflushautomatically,providedtheflushcycleoccursatleastevery24hoursforaminimumof30seconds.

Downtime1to15days–AutomaticflushingSystemsequippedwithautomatictime-basedflushsystems(withavailablefeedwater)cancontinuetoflushautomatically,providedtheflushcycleoccursatleastevery24hoursforaminimumof60seconds.

Downtime>7days–Noautomaticflushing/membranesstoredinplaceMembrane(s)shouldbecleanedanddisinfectedthenfilledwitha0.1%sodiumbisulfitesolution.Leavemembrane(s)installedinthesystem.Replacethesodiumbisulfitesolutionevery15days.

Downtime>15days–Noautomaticflushing/membrane(s)storedinsealedcontainersMembrane(s)shouldbecleanedanddisinfectedthenfilledwitha0.1%sodiumbisulfitesolution.Themembraneshouldberemovedfromthesystemandstoredinindividuallysealed(airtight)containers.Replacethesodiumbisulfitesolutionevery60days.Inallcases,themembrane(s)mustbefilledwithwaterwhenstored.Anytimeastoragesolutionisused,themembrane(s)mustbeflushedpriortouse.Seemembranerinsingguidelines(page13).

BASICS OF FOULING Aswithallfiltrationmedia,aUFmembranebecomescoveredwiththematerialitremovesfromwater.Foulingreducesthefiltrateproducedatagiventrans-membranepressureandtemperature.UFsystemsaredesignedtoregularlyflushtominimizeaccumulationofthefoulingmaterial.Therearefourtypesoffouling,whichareunderstoodbytheirrelationshiptothemembranestructure.Cake Layering – Foulingoccursastheretainedmaterialbuildsintoalayerontopofthemembranesurface.This“cake”reduceswaterflowasitgrowsinthicknessanddensity.Pore Blockage – Occurswhenaparticleorgroupofcombinedparticleslocatedirectlyoveraporeopeningonthemembranesurface.Likeacorkinabottleneck,thisblocksthewaterfromenteringtheporeandreducestheflowrateinthesystem.Cakelayeringandporeblockagearetheeasiesttypesoffoulantstoremovebyflushing.Itisalsopossibleforaproblematic“sticky”materialtodevelop,causingatypeoffoulingthatmayberesistanttoremoval.Interior Pore Fouling – Materialentersthemembrane’spores,thenlodgesinsidetheremainingporousstructureinsteadofpassingallthewaythroughthemembrane.Asthistrappedmaterialbuildsup,itreducestheavailablechannelspaceforwaterflow,eventuallyblockingoffchannelsandseverelyreducingflow.Interiorporefoulantsareremovedmostefficientlybyback-flushingratherthanforward-flushing.NOTE: Operatingthemembraneathightrans-membranepressurepromotesinteriorporefoulingwhichmaynotbereversible.

Fiber Plugging – Thisisanextremelyseverefoulingcondition.Inthiscase,themembranefiber’sfeedchannelbecomesfilledeitherwithlargeparticlesorformseverecakelayerbuildupfrommembranefouling.Flowthroughboththefiberchannelandmembraneporesbecomesseverelyrestricted.NOTE: Fiberpluggingmayoccurwithhighconcentrationsofcolloidalmaterialsandiron.Ifhighconcentrationsofironorcolloidalmaterialsarepresent,aprefiltersystemsuchasabackwashingmultimediafilterorironremovalfiltershouldbeemployed.


ULTRAFILTRATION TERMS

Back-Flush (BF) –Cleaningtechniquewherefiltrateisrunoppositeofnormaldirectionthroughthemembrane,forthepurpose of flushing the foulant off the membranesurface.Bubble Point Test – Nondestructive filter testusedtodetermineamembraneelement’sintegrityandproperinstallation,basedonthepressurenecessarytodisplacealiquidheldbysurfacetensionforces from the largest pore in the membrane.Thepressureholdtestisbasedonthebubblepointpressure.Colloid –Matterwhichisheldinwaterinaformbetweenasoluteandadiscretesuspended particle, that does not precipitatebutremainsasadispersion.Concentrate –Portionofthefeedwaterthatdoesnotpassthroughthemembraneasfiltrate,butcarriesthematterthatisretainedbythemembraneawayfromthesystem(alsoknownasrejectordrain).Cross-Flow Filtration – Operation mode wherethefeedstreamflowsthroughboththemembrane(duetohydraulicpressure)andoverthemembrane.Oneinfluentfeedstreambecomestwoeffluentstreams(filtrateandconcentrate).Disinfection – Process of removing or inactivatingorganismsinawatersupply toasafelevel.Element –Membraneconfigurationthatformsadiscreteunitwhichisthenplacedinahousingforpressurizedoperation.Depth Filtration –Removalofsubstancesthroughout the thickness or depth of the media.Disposablefibrousandwoundfiltercartridgesareexamplesofdepthfilters.Feed (Feed Water) – Water source fed to theUFtobepurified.Filtrate –Purifiedwaterthathaspassedthroughthemembrane(SeePermeate).Forward-Flush or Fast Forward-Flush (FFF) –Cleaningtechniquewherefeedflowsoverthemembranesurfaceathighvelocity to drain, instead of through the membrane.Theshearforcecausedby the high velocity removes foulants from themembranesurface.Flux –Rateoffiltrateflowthroughamembrane(usuallyexpressedinvolumeofper unit time per unit area, such as gallons per day per ft2orgfd).Fouling – Accumulation of retained matteronthesurfaceorwithintheporesofthemembrane,resultinginaloss ofperformance–mostnoticeably reducedflux.

Foulant –Anywaterbornematerialthatcontributestomembranefouling.Housing –Pressure-bearingvessel thatcontainsthemembraneelementduringoperation.Humic Acid –Variouswater-solubleorganic compounds resulting from decayedvegetablematter.Ion –Chargedsoluteinwater,atan atomic or small molecular level (examples:sodiumorcarbonate).Integrity –ConditionofaUFmembraneelementwherenointernalbypassing offeedwaterintothefiltrateexistsdue tobrokenfibers,membranetearsor failedseals.Irreversible Fouling – When fouling materialcannotberemovedwithnormalcleaningtechniques,includingfastforward-flushing,back-flushingorchemicalcleaningwhichcanresultinalossofperformance.Membrane –Semi-permeablebarrierthat permits the passage of materials only uptoacertainsizeorelectrochemicalcharacter.Microbes/Micro-Organisms – Organism thatrequiresamicroscopetobeseen. Inwater,theseincludevirus,bacteria, andprotozoan.Microfiltration (MF) – Class of membranesthatremovesparticlesofasizeabovetheapproximaterangeof0.05microns,throughsieving(orsizeexclusion).Milligrams per Liter (mg/L) – Weight to volumeratioofconcentration,equivalenttopartspermillion(ppm).Multi-Barrier – Water treatment system thatincludesmultipletreatmentstages.Municipal Water –Drinkingwatertreatedbyamunicipalityandofpotablequality.TreatmenttechniquesandfinishedqualityarebothdefinedbyStateandUSEPAstandards.Natural Organic Matter (NOM) – Any organic matter of natural origin found inwater(asopposedto,forexample,pesticides).Normalization – Conversionofrawdata to reference conditions in order to “standardize”operationtoacomparablebaseline.Operating Pressure – Hydraulic gauge pressure in the system on the feed stream, orupstreamside,ofthemembrane.Parts per Million (ppm) – Volume to volumeratioofconcentration,equivalenttomilligramsperliter(mg/l).

Permeate – Purified feed stream after passingthroughamembrane.Alsoknownas“productwater”(SeeFiltrate).Pore –Openingorvoidinamembranethatdeterminesthesizeofasoluteorparticlepassingthroughtothefiltrate.Reverse Osmosis (RO) – Separation processwhereimpuritiesofasizedowntotheioniclevelareremovedbyasemi-permeablemembrane.Reversible Fouling – Fouling material thatcanberemovedwithnormalcleaningtechniques,suchasfastforward-flushing,back-flushingorchemicalcleaning.Sanitization –Reductioninthenumberofmicrobialimpuritiestosafelevels.(SeeDisinfection).Silt Density Index (SDI) – Value calculated fromtherateatwhichawatersourcewillpluga0.45-micronmembrane.TheSDI test procedure is defined in ASTM StandardD4189.TheSDIratingprovidesan indication of rating tendency of the feed watertofoulmembranes.Solutes –Anymatterdissolvedinwater(asopposedtosuspendedinwater).OftenreportedasTDS(totaldissolvedsolids).Surface Filtration –Removalofsubstancesmainlyatthetwodimensionalplanesofthemediasurface.Standardpolymermembranesaresurfacefilters.Suspended Solids – Particulate matter heldinsuspensioninwater(usuallyparticles,butcolloidsareoftenconsideredassuspendedbecausetheyarenotfullydissolved).OftenreportedasTSS(totalsuspendedsolids).Total Oxidizable Carbon (TOC) or Total Organic Carbon (based on how it is analyzed) – Measure of the level of organic matterinwater.Trans-Membrane Pressure (TMP) – Hydraulicdrivingpressuremovingwaterthroughthemembrane,measuredasthedifferencebetweenfeedandfiltrate(upstreamanddownstream)sidesofthemembrane.Alsotermed“effectivepressure”.Ultrafiltration (UF) – Process using hydraulicpressureandasemi-permeablemembranefortheseparationofcomponentsinsolutionsandsuspensions.Membraneporesareofasizethat allowspassageofwater,butwillretainnon-ionicsolutesbasedprimarilyontheirphysicalsize.

PENTEK®

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FREQUENTLY ASKED QUESTIONSTheFAQsbelowarespecifictothePentair® FreshPoint® Ultrafiltration (UF) system, although they generally applytomostotherhollowfiber UFsystemsaswell.

Q. Is this device designed for use on microbiologically unsafe water?

A. FreshPointUFisbestusedaspartofamulti-barriersystemtotreatmicrobiologicallyunsafewaters.

CAUTION: Onlysystemsthatare3rdparty-certifiedaswaterpurifiersandmeetstateandlocalregulationscanbeusedtopurifyunsafedrinkingwatersupplies.

Q. Will UF remove cysts from my water?

A. Yes, the FreshPoint UF system reduces cysts such as CryptosporidiumandGiardiabymechanicalmeans.

Q. How often does the FreshPoint UF membrane need to be replaced?

A. Membranelifevarieswidely andisdependentonfeedwaterqualityandoperatingconditions.A3-to5-yearmembranelifeisexpected for a properly applied, wellmaintainedsystem.

Q. What is the nominal pore size?A. TheFreshPointnominalporesize

is0.02microns.

Q. Is the pore size rating absolute?A. No,theporesizeisnominal.

Q. How do I know the FreshPoint UF System is working?

A. Amembraneintegritytestshouldbeperformedtodetermineifthemembraneisworking.

Q. How do I test the integrity of the membrane?

A. An air test is used to ensure thattheFreshPointmembraneintegrityismaintained.

Q. How long does a membrane integrity test take?

A. Theintegritytesttakesabout1/2hourtocomplete,butthenneedstobefollowedbysanitizing.

Q. How much water will the UF system use for flushing?

A. FreshPoint UF uses three to four gallonsperflushcycle.

Q. Can UF be used to remove iron from my water?

A. FreshPointUFwillremovesuspended iron particles and colloidsabovethemembraneporesize.However,itisonlyrecommended as a polishing iron filter as high concentrations of ironcouldplugthefiberbores.FreshPointwillnotremovedissolvediron.

Q. How frequently will the UF system flush?

A. Flushingfrequencyisprogrammable.Thedefaultsetting for FreshPoint UF is 100gallonsoronceperday,whicheveroccursfirst.

Q. Will my water flow be interrupted while the unit flushes?

A. Waterwillcontinuetobesuppliedwhilethesystemflushes,butyou may notice a reduction in pressure.Thisreductioninpressurecanbeminimizedbyinstallingaproductstoragetank.

Q. Do I have to do anything special with the FreshPoint UF System when I go on vacation?

A. If you are going to leave your waterturnedonwhileyouareonvacation,thesystemwillcontinueto flush daily and nothing needs tobedone.Ifyouwillbegoneforan extended period and shutting offthewatercompletely,thenpreservativesshouldbeaddedtothemembrane.

Q. What is the maximum flow rate? A. Maximumflowrateisdependent

onoperatingconditions.FreshPointModelU440isratedatamaximumof10gpmatstandardoperatingconditions.

Q. What is the pressure drop at the maximum flow rate?

A. Pressure drop is dependent on operating conditions and feed watertemperature.FreshPointUFhasapressuredropof<15psidatmaximumflowrate/standardoperatingconditions.

Q. What is the continuous flow rate?A. Thecontinuousflowrateis

dependentonoperatingconditions. TheFreshPointU440isratedatacontinuousflowof3gpmatstandardoperatingconditions.

Q. What is the pressure drop at the continuous flow rate?

A. The pressure drop is dependent on operating conditions and feedwatertemperature.TheFreshPointU440hasapressuredropof<10psidatcontinuousflowrate/standardoperatingconditions.

EPA EST. NO. 086074-NH-001


Q. What cleaning chemicals are recommended?

A. Cleaningsolutionsvarybyfoulantand include: chlorine, hydrogen peroxide, sodium hydroxide, citric acidandhydrochloricacid.

Q. Is any prefiltration recommended?A. The need for prefiltration is

dependentuponfeedwaterquality.SeetheFeedWaterQuality section of this guide (pages7-9)formoreinformation.

Q. What is the permitted operating pH range?

A. ApHrangeof3to10ispermissibleforFreshPointUF.

Q. What is the required operating pressure range?

A. FreshPoint®canbeoperatedatinletpressuresupto120psig.However,trans-membranepressureshouldbelimitedtopreventlongtermfouling.Seemembranespecificationsheetsformoreinformation.

Q. What is the permitted operating temperature range?

A. FreshPointUFcanbeoperatedwithtemperaturesfrom34°to104°F(1.1°to40°C).

Q. Can I install this unit outside?A. Outdoor installation is not

recommended due to the temperature limits for the FreshPointUFsystem.

Q. What is the drain flow rate?A. TheFreshPointU440drainflowis

7gpmmaximum.

Q. What size and length drain line is permitted?

A. Thesizeofthedrainlineshouldbeaminimumof0.75"tomeetcoderequirements.Drainlinelengthshouldbeminimizedtopreventwaterhammerwhentheflushvalvecloses.

Q. Does the module need to be installed vertically?

A. The FreshPoint UF module shouldbeinstalledverticallyforproperventing.

Q. What is the maximum inlet chlorine concentration allowed?

A. Maximum continuous inlet chlorine concentration for FreshPoint is 4mg/l.

Q. What is the maximum inlet turbidity?

A. Maximum recommended inlet turbidityforFreshPointUFis 5NTU.PleaserefertotheFeedWater Quality section of this guide formoreinformation.

Q. What outlet turbidity can be expected?

A. TheFreshPointoutletturbidityisexpectedtobe<1.0.

Q. What outlet SDI can I expect?A. The FreshPoint outlet SDI is

expectedtobe<2.0.

Q. What system flushing will be required after installation?

A. TheFreshPointmembrane(s)mustbeflushedforapproximatelyonehourpriortoinitialuse.

Q. Do membranes have a shelf life?A. Membranematerialisstable,

however,amaximummembraneshelf life of eight months is recommended (if maintained in itsoriginalpackaging).

Q. What flocculants could be used ahead of the membrane(s)?

A. Polyelectrolytescanbeusedaspartofanin-linecoagulation/ filtration process prior to the FreshPointUFmembrane(s),butgreatcaremustbeusedtoavoidoverdosingofthepolyelectrolyte.Overdosing polyelectrolyte can irreversiblyfoulUFmembranes.

Q. What lubricants should be used on seals?

A. Glycerin is the preferred lubricant.(Siliconewillfoulthe UFmembrane(s).)

Q. Is a dropped membrane safe to use?

A. Anydroppedmembrane(s)shouldbeintegrity-testedtoensurethatitwasnotdamaged.

Q. What is the preservative solution in a new membrane?

A. Sodiumbisulfiteandglycerin.

Q. Do UF systems have to be installed with a flush tank?

A. No,howeverflushtanksarepreferred for most applications tominimizepressurereductionduring flush cycles and periods ofhighflow.Theyalsoprovidewaterforback-flushingofthemembranes.

22 P ENTA IR

PENTEK®

TROUBLESHOOTING GUIDEThistroubleshootingguidefocusesonbasicmembrane/processissues.Seeaspecificsystem’soperatingandmaintenancemanualfortroubleshootinginformationforspecificUFsystems.

PROBLEM POTENTIAL CAUSE CORRECTION

Low flow / pressure available.

Unit is flushing.Wait for flush to be completed.

Install a pressure tank to maintain system pressure during flush cycles.

Prefilter(s) is plugged (if so equipped). Change prefilter(s) – disposable type.Regenerate back-washable filters.

Feed water pressure is too low. Increase UF feed water pressure.

Membrane is fouled.

Decrease the volume between flushes.Increase the flush time.

Decrease the time between flushes.Chemically clean/sanitize.

No product water flow.

Bypass valves are not in the correct position. Correct bypass valve position to restore flow.

Inlet water is shutoff. Open inlet valve(s).

Prefilter(s) is plugged (if so equipped). Change prefilter(s) – disposable type.Regenerate back-washable filters.

Membrane is fouled.



Unpleasant taste and odor in the water.

Membranes were not sufficiently flushed following installation, disinfection, or cleaning.

Follow the system startup guide for flushing new membranes.

Water has become stagnant from low water use. Perform additional flushing of the system per operation manual.

Membrane is fouled.



Suds in the water. Membranes were not sufficiently flushed following installation, disinfection, or cleaning.

Follow the system startup guide for flushing new membranes.

System not producing the expected water quality.

Impurities are unable to be removed by UF system.

Refer to UF application guide for approximate removal capabilities.

Add additional treatment steps to aid in impurity removal.

Seals/internal connections are leaking. Confirm with pressure decay test.Replace internal seals.

Membrane has an internal leak. Confirm with pressure decay test. Replace membrane.

System is flushing continuously.

Drain solenoid valve is stuck open. Remove debris from the valve.Replace the drain solenoid valve.

System controller circuit board is sending continuous flush signal.

Confirm the controller is programmed correctly.Contact your Water Specialist for service.


MEMBRANE DATAMembrane Data Sheet – FreshPoint® Ultrafiltration System (Model U440)

UF MEMBRANE SPECIFICATION UNIT OF MEASURE

SPECIFICATION VALUE

Membrane Model n/a Pentair® U440

Membrane Area sq. ft. 51.0

Peak Flux Rate gfd 280.0

Pure Water Continuous Flux Rate gfd 180.0

Well Water Continuous Flux Rate gfd 85.0

Surface Water Continuous Flux Rate gfd 35.0

Peak Flow Rate (Not Continuous) gpm 9.9

Pure Water Continuous Flow gpm 6.4

Well Water Continuous Flow gpm 3.0

Surface Water Continuous Flow gpm 1.2

Trans-Membrane Pressure – Continuous psid 11.5

Trans-Membrane Pressure – Maximum psid 36.0

Trans-Membrane Pressure – Back-Flush psid 36.0

Molecular Weight Cut-Off Dalton 150,000

Operating Temperature – Minimum °F 34

Operating Temperature – Maximum °F 104

Operation n/a Inside Out

Flush – Fluid n/a Water

Flush – Direction n/a Forward and Back

Membrane Type n/a Multibore Hollow Fiber

Capillaries per Fiber n/a 7

Hollow Fiber ID in. 0.04

Hollow Fiber OD in. 0.17

Diameter – Nominal in. 4

Length – Nominal in. 38

pH Range – Continuous pH 3 to 10

NaOCl – Continuous mg/l 4

pH Range – Intermittent (Cleaning) pH 1 to 13

NaOCl – Intermittent (Cleaning) mg/l 200

H2O2 – Intermittent (Cleaning) mg/l 500

NaOH – Intermittent (Cleaning) pH 13.0

HCl – Intermittent (Cleaning) pH 1.0

Citric Acid – Intermittent (Cleaning) pH 1.0

FILTRATION & PROCESS5730 NORTH GLEN PARK ROAD, MILWAUKEE, WI 53209P: 262.238.4400 | F: 262.238.4404 | WWW.PENTAIRAQUA.COM | CUSTOMER CARE: 800.279.9404

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