process water - alliance for water efficiency

PROC1

Process WaterWater used by industries and businesses to produce a product or affect a process is known as “process water.” This section discusses the following industries and their uses of process water:

• foodandbeverages• autorepairandservice• papermanufacturing• metalfinishing

Thechapterwillnotcoveropportunitiestosavewaterbyusingefficientplumbingfixturesandirrigationsystems,sincethesearecoveredelsewhereinthisreport.

Whilemuchoftheinformationhereinisspecifictotheproductbeingmanufac-turedorservicebeingprovided,thepotentialtodesignwaterconservationintotheprocessrangesfromsimplyadjustingtheequipmentorprocesstouselesswaterto adopting new practices or processes that use no water at all.

Food-and-Beverage Processing

Thefood-and-beverage-processingindustryincludesawiderangeofproductsandmanufacturingprocesses:

• bakery/pastryshops• industrialbakeries• breweries• wineries• softdrinkandjuicemanufacturers• dairy-foodprocessors• meat,fish,andpoultryprocessing• frozen-foodproducers• canneries• snack-foodmanufacturers• grocerystoresandrestaurantsthatproducefoodproductsforsale• otherfoodanddrinkprocessors

Thefood-and-beverageindustryuseswaterformanypurposes.Thequalityandpurityofthewaterisofprimaryconcernsinceitisusedtomakeproductsthatwillbeconsumed.Waterisalsousedtocleanandsanitizefloors,processingequipment,containers,vessels,andtherawfoodproductspriortotheirprocess-ing.Hotwater,steam,cooling,andrefrigerationalsorequiresourcewater.De-signingandbuildingafacilitythathasareducedrequirementforwaterincludes:

• designingthefacilityforeaseofcleaning• providingadequatemetering,submetering,andprocesscontrol• takingadvantageofdrymethodsforcleanupandtransport

Few in-dustrial processes involve no need for water. In every in-dustry that uses wa-ter, careful planning and design can mini-mize water waste and optimize the ben-efits re-ceived from the water that is consumed.

PROC2

• usingproduct-andbyproduct-recoverysystems• incorporatingwaterreuseandrecycling• designingforminimalornowateruse

DescriptionofEnd-UseandWater-SavingsExamplesBecauseofthecomplicatedandhighlyvariednatureofthefoodandbeveragemanufacturingindustry,providingasimpleguidetowaterefficiencythatcoversalltypesoffacilitiesisnotpossible.Beforebeginningthisdiscussionofwaterconservationinfoodprocessing,oneshouldrememberthathealthandsanitationareoverridingconcerns.Allactionstoreducewaterusemustbemeasuredagainstthispri-maryconsideration.

Thefollowingexampleillustrateswayswatercanbeusedinthesoft-drinkindustry.Potablewaterisfirsttreatedtosoftenitand,ifneeded,toremoveadditionalminerals.Itischilledandblendedwithflavoringsandsweeteners,thencarbonated.Cansorbottlesarefilledandsealed,thenrinsedandsentthroughawarmingbathtoavoidcreatingcondensateintheopenairandensuretheyaredrybeforepacking.Theeightmajorwater-usingprocessesare:

• watersoftening,whichrequiresperiodicfilterbackwash• waterincludedintheproduct• watertocleanandrinsecans• watertowarmcansafterprocessing• watersprayedontheconveyorlineasalubricant• watertooperatecoolingtowersforrefrigerationequipmentandboilersforheat• watertosanitizeandcleantheplantandvessels• waterforemployeesanitation,irrigation,etc.(NorthCarolinaDepartmentofEnvironment,Health,andNaturalResources,1998).

Carbonated Soft Drink Manufacturing

Syrup Carbon Dioxide

Proportioner

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Labeling, Inspection & Packing Bottling

ConveyorOperation

FinishedProduct

Cooling / Carbonation

WaterTreatment

OtherWaterUse

Based upon concise.britannica.com/ebc/art-54000

Process Water Watersmart Guidebook

PROC3

Eachofeightmajorwater-usingactivitiesinthefood-andbeverage-manufacturingsectorwillbede-scribed,alongwithexamplesfromspecificindustrieswhereappropriate:

•cleaningandsanitation•thermodynamicprocesses• transportationandcleaningoffoodproducts• equipmentcleaning• container(bottles,cans,cartons,etc.)cleaning• lubricatingcanandbottleconveyorbelts• canandbottlewarmingandcooling• productingredients

Cleaning and Sanitation

Informationonfloorcleaningandthecleaningofoutdoorareasisfoundinallsectors(see“FoodSer-vice”).Drycleanup,preventingspillsbycontrollingprocessingequipmentandleaks,andproperstorageand handling of ingredients all reduce water needed for cleaning.

Thefollowingtablesummarizestheimportanceofwaterforcleaninginfourfood-processingsectors(EnvironmentalTechnologyBestPracticesProgram).

Water Use by Major Food-Processing TypesType of Process Percent of Water for

CleaningBakery 70

Soft drink 48Brewing 45

Jam 22

Thermodynamic Processes

Anothercommonuseofwaterisintheproductionofsteamandhotwaterandincoolingtowers,asdiscussedinthesectiononThermodynamicProcesses.Meteringandsubmeteringareimportantinun-derstandinghowmuchwaterisusedineachprocessortypeofequipment.Properprocesscontrolsareessentialtomanagingwaterandenergyuse.

Transportation and Cleaning of Food Products

Theuseofflumestobothtransportandcleanproduce(fruitsandvegetables)iscommon.Waterisalsousedinthecleaningandprocessingofmeat,poultry,andfish.Commonwater-conservationtechniquesbegin with reducing water use by:

• recyclingtransportwater• adjustingdesignofflumestominimizewateruse• usingflumeswithparaboliccrosssections• providingsurgetankstoavoidwaterloss• usingfloatcontrolvalvesonmakeuplines• usesolenoidvalvestoshutoffwaterwhenequipmentstops

Watersmart Guidebook Process Water

PROC4

Allthesetechniquescanreducetheneedforwater,butchangingtheprocesshasevenmorepotential.• Replaceflumingwithconveyorbelts,pneumaticsystems,orotherdrytechniquestomove

food products.• Installspraystowashfood.• Usemechanicaldisksandbrushes.• Installcounter-flowwashingsystems.• Controlspraysonbelts.• Controlprocessequipmenttoreducewaste.

Grocerystoresandsmallerbakeriesshouldfollowgoodfood-servicesectorwashingpracticesformeats,fruits,vegetables,andotherfoodproductsbeforefinalpackaging.Further,ensurethatallwater-usingprocessequipmenthasproperlevelandflowcontrols(Costello).

Asanexample,aMinnesotavegetable-processingfirmreducedwateruseforconveyingcornby20per-cent,or1,000gpd,justbyemployingpropercontrolsandrecycling20percentofthewaterintheflumes(NorthCarolinaDepartmentofEnvironmentandNaturalResources).

Equipment Cleaning

Equipmenttobecleanedrangesfromlargeprocessfacilitiesandequipmenttothehand-heldequipmentandcookingutensilsfoundinsmallerbakeriesandgrocerystores.Smallerutensilsshouldbewashedfollowingtheware-washingconsiderationsfoundinthe“FoodService”section.Largerequipmentthatcannotbedisassembledeasilymustbecleanedinplace.Choicesofproceduresforcleaningequipmentcanyieldmultipleadvantagesincluding:

• productrecovery• reducedwastewaterloading• reducedwateruse• reducedchemicaluse

Gooddesignandlayoutofequipmentareessentialtoeasycleaning.•Designequipmentthatminimizesspills,leaks,andresidualproductthatmustberemoved

before cleaning.• Forclosedsystemssuchastanksandpiping,eliminate“lowspots”soequipmentcaneasilyandcompletelydrain.

• Provideeasyaccesstoallareasoftheequipmentthatmustbecleaned.• Selectmaterialsandsurfacesthatareeasilycleaned.• Changeprocedurestoreducetheneedforcleaning.

Asanexample,amedium-sizedbakeryinMinnesotaused65to100bucketsadayforstoringicing.Washingthesebucketsrequiredapproximatelythreehoursoflaboreachday,andicingthatstucktothebottomandsideswaswasted.Theyreplacedtheone-bucket-at-a-timepreparationmethodwithalargevat.Thisreducedthenumberofcontainersthathadtobewashedtothreelargeonesandsavedupto$2,000ayearinicingthatwasbeingwasted.Italsoreducedwashingtimefromthreehoursadaytoafewminutes,thussavingwater(MinnesotaTechnicalAssistanceProgram).

Clean-in-placemethodsrangefromfloodingtheequipmentwithhotwater,detergent,andchemicals,todrycleaning.Drycleaningasafirststepisessentialforsavingwater,sinceitreducesthewaterneededinthewet-cleaningphase,sometimeseliminatingitcompletely.Drycleaningincludes:

•removingasmuchotherwise-wastedproductaspossiblebypouringandstorageforfutureuse• scrapingequipmentandvesselstoremoveasmuchwasteaspossible


PROC5

• usingdrybrushes,cloths,andpapertowelstoremovewaste• usingwettowels

Drycleaningcanbelaborintensive,butthelaborcostsareoffsetbythepotentialtorecoverproduct,reducepollutionloading,andpotentiallycleanequipmentmorethoroughly.Italsoallowsemployeestocloselyexamineequipmentanddiscoverpossiblemechanicalproblemsatanearlystage.

Wherewaterisusedforcleaning,itisimportanttoemploythe“multiplealiquots”concept,inwhichitisbettertouseanumberofsmallervolumesofwatertocleanthanoneverylargevolume.Formix-ers,extrusionandmoldingequipment,conveyorbelts,andotheropenequipmenttowhichonecangaindirectaccess,cleaningshouldstartwithphysicalremovalofresidualmaterialsandthenbefollowedbywetwashing.Fourprinciplesofwetcleaningare:

•usehigh-pressure,low-volumesprays•installshutoffsonallcleaningequipment•usedetergentsandsanitizingchemicalsthatareeasilyremovedwithminimumwater•installandlocatedrainsandsumpssowaterandwastesenterquicklytopreventtheuseofahoseasabroom

Forclosedvessels,pipes,anddeliverytubs,cleaningtechniquesareverydifferent.Theyrequire“CleaninPlace”(CIP)and“SanitizeinPlace”(SIP)methods.Beforecleaningaprocesspipingsystem,itisessentialtoremoveasmuchoftheproductaspossible.Atitssimplest,thisinvolvesdrainingthetankorpipingsystem.Designingthepipingtoeliminatelowspotsthatcantrapproductisamajoraidinthisprocess.Followingthis,severalmethodscanbeemployedtoremoveextraproductandcleanthevesselandpiping.Forpiping,threemethodsfindcommonuse,including:

•slugrinsing•airblowing• “pigging”

Piggingisaprocessinwhichaflexiblerubberorplasticprojectileisforcedthroughapipetopushtheproductout.InEuropeatechniqueusing“icepigging”hasrecentlybeendevelopedthatusesiceslurry.Thepigisforcedthroughthepipewithair,water,orcleaningfluids.CIPsystemscanalsobedesignedtoreusewaterandchemicals,ifproductsafetyallows.

Forvessels,aballthatsprayswaterinalldirectionshashistoricallybeenemployedforwashing.Replac-ingthatwithahigh-pressure,low-volumerotatingspraythatwashesproductdownthesidescanreducetheamountofwaterneeded.Inmanycases,thisdilutefirstrinsecanbecapturedandproductrecovered.Inthedairyindustry,pasteurizationtanksmustbefilledwithhotwateraftercleaningtopre-pasteurizethevessels.ThiswaterisoftencapturedandreusedaswashwaterforotherCIPneeds,thussavingbothwaterandenergy,sincethewaterisalreadyhot.

Vessel-,barrel-,andcask-cleaningwatercanalsobeusedforirrigationinthewineryindustryand,tosomeextent,inthebrewingandvegetable-andfruit-processingindustries.Theuseofthiswaterforir-rigationalsoremovessolidsandBODfromthewastestreamandplacesitwhereitbecomesanassettogrowingplantmaterial.

Container (Bottles, Cans, Cartons, etc.) Cleaning

Cleaningbottles,cans,andcontainerspriortofillingiscommonthroughouttheindustry.Forreturnablebottles,theuseofairburststoremovelosedebrisandmaterialsandthereuseofwaterfromcan


PROC6

warmingandotheroperationsarecommonwaystoreducewateruse.Othermethodsincludeuseofpres-surespraysandsteaminsteadofhigh-volumesofhotwatertocleancontainers.

Onebreweryrecoveredthebottlewashwateranduseditforwashingthecratesinwhichthebottlesareplaced.Thissavedmorethan4,500gallonsofwateraday(Hagler).

Cleaningcans,bottles,andcontainersaftertheyhavebeenfilledoffersotheropportunities.Somespill-ageandoverfillingisinevitable,butwithproperequipmentcontrolthiscanbeminimized.Reducingwaterusetoaminimumandpassingthewashwaterthroughnanofiltrationcanrecoverboththesugarsandproductforuseasanimalfeedorforgrowingyeast,whilethewateriscleanedandmadeavailablefor additional reuse.

Lubricating Can and Bottle Conveyor Belts

Oneofthemostunusualusesofwaterinthefoodandbeverageindustryisasalubricantforconveyorbeltsthatmovecansandbottles,sotheycan“slip”easilyonthehigh-speedconveyorbeltsandnottipover.Thiswaterissoftenedandmixedwithbiocidesandsoapsbeforeitissprayedontotheconveyors.Manyattemptshavebeenmadetousedrylubricationsystemsorfindotherwaystomovethecansandbottlesatthehighspeedsneededinmodernoperations,buttheuseofwaterasalubricantremainsthestandardforthisindustry.Manyhavebeenabletoreducewateruseorevencaptureandrecoverbeltlubricantwater.InAustralia,eightCadburySchweppesplantsaretestingdrylubricantconveyorsys-tems(SmartWaterFundofAustralia).Fornow,ensuringthatthespraynozzlesareproperlysized,wellaligned,andequippedwithautomaticshutoffsisthebestthatcanbedone.

Can and Bottle Warming and Cooling

Waterhasavarietyofapplications,rangingfromcoolingorheatingcanstouseasaheat-transferagent.Thiswaterremainsrelativelycleanandisanexcellentsourceofwaterforreuse.Waterisusedtocoolcansaftertheyhavebeenremovedfrompressurecookersinthecanningprocess.Inmostcasesthiswateriscooledinacoolingtowerorarefrigerationunitthatemploysacoolingtowerintheprocess.Inthewarmingprocess,cansandbottlesfromthebeverageindustrythathavebeenfilledwithcoldliquidsareheatedsocondensatedoesnotformonthemandtheydrymorequicklybeforepacking.Theseopera-tionsoffersignificantopportunitiesforreuseforalmostalloftheotherwaterneedsintheoperation,exceptwherepotablequalityisrequiredbyregulation.Examplesofreuseinclude:

•firstrinseinthewashcycle•canandbottleshredderandcrusheroperations•filterbackwashforproductfilters•chemical-mixingwater•defrostingofrefrigerationcoils•useforequipmentorfloorcleaning•flushingoutshipmentcontainersandcrates•cleaningoftransporttruckandrailcars•gutterandsewerflushing•flumingandwashingoffruitsandvegetables•makeupwaterforconveyorlubricationsystems•irrigation•cooling-towermakeupwater


PROC7

Product Ingredients

Mostfoodproductscontainwaterand,inthecaseofthebeverageindustry,waterisusuallyamajorcomponentoftheproduct.Tobothreducewateruseandloadingonwastewatersystemsrequiresproperinstrumentationandcontroloffillingandpackagingoperations.Thesolidwasteby-productsofbrew-ery,winery,fruitandvegetableprocessing,andmeatprocessingoperations,asexamples,canoftenbeusedasanimalfeedorberenderedforotheruses.Liquidwastescanalsofinduseinotherindustries,forexample,fruitjuiceby-productcanbeusedtoproducealcohol.

Water-SavingsPotentialExamplesofpracticesandwatersavingsareprovidedabove.Becauseofthevariednatureoftheprod-uctsandprocessesfoundinthefood-and-beverage-processingindustry,water-savingspotentialisslightly different for each. These six design principles will help build water efficiency into a facility:

•designthefacilityforeaseofcleaning•provideadequatemetering,submetering,andprocesscontrol•setupthefacilitytotakeadvantageofdrymethodsforcleanupandtransport•useproductandby-productrecoverysystems•incorporatewaterreuseandrecycling•designforminimalornowateruse

Cost-EffectivenessAnalysisBecauseofthehighlyvariednatureofthefood-and-beverage-manufacturingindustry,acostanalysisacrosstheindustryisnotpossible.However,severalcostareasneedtobetakenintoconsideration,includingtheseseven:

•water•wastewaterdisposal•pretreatment•chemicalsforcleaningandsanitizing•solidwastehandling•energy•potentialtoproduceamarketableby-product

Recommendations Proven Practices for Superior Performance

•Requirethatnewfacilitiesprovidealistofpossibleareasofwaterrecoveryandreuse.•Requirethatallmajorwater-usingareasbeseparatelymetered.•Requireautomaticshutoffandsolenoidvalvesonallhosesandwater-usingequipment,where

applicable.Additional Practices That Achieve Significant Savings

•Usepigging,airblowing,orslugwashingaspartofCIPsystemsforprocesspipes.•Usefloorcleaningandvacuummachineswherepossible.•Minimizetheuseofwater-lubricatedconveyorbelts.•Minimizetheneedtouseahoseasabroombyinstallingdrainsclosetoareaswhereliquid

discharges are expected.•Providepressure-washingequipmentinplaceofwashdownhoses.


PROC8

ReferencesA&BProcessingSystems(201SouthWisconsinAve,Stratford,Wisconsin).A Guide to Clean In Place

(CIP).

__________. Product Recovery Systems (Pigging Systems) in the Process Industry.

Aquacraft,Inc.fortheCaliforniaDepartmentofWaterResourcesandU.S.BureauofReclamation.2003. Demonstration of Water Conservation Opportunities in Urban Supermarkets.

Carawan,RoyE.Liquid Assets for Your Bakery.March1966.NorthCarolinaCooperativeExtensionServicePublicationNo.CD-41.

CommonwealthofPennsylvania.DepartmentofEnvironmentalProtection.Water Conservation Ideas for the Beverage Industry.

Costello,Jim.Spring2001.“BrewingUpPreventionIdeas.” Newsletter.UniversityofMinnesotaTech-nicalAssistanceProgram.

Encyclopedia Britannica. “CarbonatedSoft-DrinkManufacturing.”concise.britannica.com/ebc/art-54000.

EnvironmentalTechnologyBestPracticesProgram.Reducing the Cost of Cleaning in the Food and Drink Industry. ReportNo.GG157.www.etsu.com/etbpp/.

GDSAssociates,ChrisBrownConsulting,Axiom-BlairEngineering,Inc.,TonyGregg,PE.2004.Wa-ter Conservation Best Management Practices Guide. TexasWaterDevelopmentBoard.Austin,Texas.

Galitsky,Christian.2004.Best Winery: An Integrated Benchmarking and Energy and Water Man-agement Tool.LawrenceBerkeleyNationalLaboratory.

HaglerBaileyConsulting.1997.Pollution Prevention Diagnostic Assessment — Brewery. UnitedStatesOfficeforInternationalDevelopment.OfficeofEnvironmentalandNaturalResources.

Hoffman,H.W.(Bill).March2006.Building Reduced Water and Wastewater Cost into the Design. AustinWaterUtility.Austin,Texas.

Kentish,Graeme,andMorgan,Peter.October2006.Conversion of Product Conveyors from Wet Lu-brication to Dry Lubrication. CadburySchweppes,Tullamarie,Victoria,Australia.

MarylandDepartmentoftheEnvironment.Water Saving Tips for Food Processing Facilities.

__________. Water Saving Tips for the Beverage Industry.

MassachusettsWaterResourcesAuthority.“Beverage/FoodProcessingIndustries.”Water Conserva-tion Bulletin No. 3.

MinnesotaTechnicalAssistanceProgram.October2004.Best Management Practices — Bakery. Uni-versityofMinnesota.


PROC9

NorthCarolinaDepartmentofEnvironmentandNaturalResources,DivisionofPollutionPrevention.August1998.Water Efficiency Manual for Commercial, Industrial, and Institutional Facilities.

Ogunbameru,Gus,Ph.C.,Ch.E.2004.Best Management Practices for Selected Industries and Ad-ditional Resources.MassachusettsOfficeofTechnicalAssistance.

PlattsResearchandConsulting.2002.Management of Energy Cost in Grocery Stores.McGrawHillCompanies,Inc.

Rausch,KentD,andPowell,MorganG.1997.Dairy Processing Methods to Reduce Water Use and Liquid Waste Load.CooperativeExtensionService.KansasStateUniversity.Manhattan,Kansas.

NorthCarolinaDepartmentofEnvironment,Health,andNaturalResources.August1995.A Soft Drink Bottling Company — North Carolina.

SmartWaterFundofAustralia.2007.“CadburySchweppesAustralia&NewZealandaimstosaveover20,000kilolitresofwatereachyearthankstotheSmartWaterFund.” www.smartwater.com.au.

Automotive Services

Theautomotiveserviceandrepairindustryisoneofthemostubiquitoustypesofcommercialenterprisesinanycity.Establishmentsinclude:

• servicestations• oilchange/lubrication• bodyrepair• tune-upshops• full-servicerepairshops• fleetmaintenance• tireservice

Thedesignofawater-efficientshopdependstosomeextentuponthetypeofserviceoffered.Newair-qualityregulationshavealsomeantthatshopshaveswitchedfromsolvent-basedparts-andbrake-clean-ingsystemstoaqueous-basedsystems.Floor-cleaningwithdrymethods,preventingspillsandleaksfromenteringthewastewaterdischargesystem,andtheproperdesignofoilseparatorshaveasmuch

todowithpollutionpreventionastheydowithwaterconservation.Washingofvehiclesiscoveredinaseparatesection.

DescriptionofEnd-UseandWater-SavingsPotentialThree areas of operation offer both reduced water- and pollution-loading possibilities:• properdesignofaqueousparts-and

brake-cleaning• preventingpollutionandreducing

water use in shop-floor cleaning • properhandlingofspentfluidsand

oilsAqueous Parts Washer

fastt.navsea.navy.daps.dla.mil/frames/rec_4.htm


PROC10

Aqueous Cleaning Equipment

Thedevelopmentofaqueousparts-andbrake-cleaningequipmenthasbeendrivenbyair-qualityre-quirements.Suchsystemscanemployfiltrationforsludgeremovalandoilskimming.Byfilter-cleaningthewater,itcanberecycled,thussavingontotalwater-use.

Floor Cleaning

Keepingfloorscleaninthefirstplaceeliminatestheneedforfrequentwashing.Methodsinclude:•installingsecondarycontainersunderfluids-storagecontainerstocatchleaksandusingdripplansundervehiclesbeingworkedon

•usingdrycleanupwithhydrophobicmopsforoilandusingabsorbentmaterials(kittylitter,ricehulls,pads,rags,pillows,andmats)tocleanupspills

•sealingfloorswithanepoxymaterial,whichsignificantlyaidsincleanupandpreventsoilsandliquidsfrompenetratingconcretefloors

•providingfloor-cleaningequipmentthatscrubsandvacuumsupitsownwater•eliminatingtheuseofopenhosesforcleanupandusingpressure-washingequipmentinfre-quentlyandformajorcleanupeventsonly

• markingdrainsclearlytoensurethatfloordrainsareclearlydifferentiatedfromstormdrainsand all floor drains are connected to an oil separator

Handling of Spent Fluids

Recoveryandrecyclingofradiatorflush-waterbothsaveswaterandreducespollutionloading.Usingstoragevesselsdesignedtoholdspentantifreezeandotherfluids,suchasoilandtransmissionfluid,botheliminatestheneedtocleanandflushthesefluidsdownadrainandisrequiredaspartofmodernpollution-controlmethods.Wateruseinfacilitiesthatrecycleradiatorflush-waterhasbeenshowntobelessthan10percentofwateruseinnon-recyclingfacilities(SanAntonioWaterSystem).

Cost-EffectivenessAnalysisAcostanalysisofmeasurestoreducebothwateruseandpollutionfromtheauto-repairindustryisnowrequiredinpartbyair-pollutionandwater-pollutionregulations.Offsetstothesecostsinclude:

•reducedpretreatmentcosts•reducedcostforsolvents•reducedwateruse


• Requirenewfacilitiestoprovidesecondarycontainerstocatchdrips,leaks,andspillsfromstoredliquidsandsolvents.

• Requireshopfloorstobesealedtoensureeasycleanup.• Requireautomaticshutoffandsolenoidvalvesonallhosesandwater-usingequipment,where

applicable.• Requireaqueousparts-andbrake-cleaningequipmenttoemployrecirculatingfiltrationtominimizetheneedtodumpwater.

• Requirealldrainstobeproperlyidentified.• Haveproperfacilitiesforthecapture,storage,andrecyclingofspentfluids,oils,andfuels,includingantifreezeandradiatorflush-water.


PROC11

Additional Practices That Achieve Significant Savings• Havepressure-washingequipmentavailable.• Havedrippansavailableatworkstationstoplaceundervehicles.

ReferencesAqueouspartswasher.fastt.navsea.navy.daps.dla.mil/frames/rec_4.htm.FASTTDirectorCharlesE.

Tittle,[email protected],DSN326,(202)781-1833,ext.230.

CaliforniaDepartmentofToxicSubstanceControl.P2 Opportunities Checklist for Vehicle Mainte-nance Activities.

SanAntonioWaterSystem.June1998.Water Saver Awards.

U.S.EnvironmentalProtectionAgency.Region9.Auto Repair and Fleet Maintenance Pollution Pre-vention. www.epa.gov/region09/waste/p2/autofleet/factauto.html.

U.S.Navy.Navy Water Conservation Guide for Shore Facilities. portal.navfac.navy.mil/pls/portal/docs/PAGE/NAVFAC/NAVFAC_WW_PP/NAVFAC_NFESC_PP/ENVIRONMENTAL/EQIFS/WASTEWATER/08_WASTEWATER/lowflow.pdf

Printing and Paper Manufacturing

DescriptionofEndUseAtfirstglance,printingandpapermanufacturingappeartobeverydifferentindustries,butaccordingtoclassificationbytheU.S.CensusandtheNAICS—NorthAmericanIndustrialClassificationSystem—papermanufacturingrangesfrommakingpaperfromtreestomanufacturingconvertedpaperproducts,suchaspapercontainers,cups,boxes,bags,coatedpaper,envelopes,andstationeryproducts.Thefocusofthisdiscussionisthemanufacturingofconvertedpaperproductsandprinting.

Producingpaperfrompulpwoodandotherfibersourcesisthebeginningprocessforallpaper.Itisalsothemostwater-andenergy-intensivestageinthelifeofapaperproduct.Fivegallonsofwaterareusedtomakeonepoundofpaper(Weyerhaeuser).Recyclingpaperandcardboardproductscutsthisenergyandwateruseinhalf(Kinsella).AccordingtoConservatree,anorganizationthatpromotespaperre-cycling,mostrepulpingforrecycledpaperisdoneatpulpandpapermills,wherepaperismade,orinspecialfacilitiesthatusetheproducttomakesuchthingsascelluloseinsulationorpulpproducts,suchas egg cartons.

Atthesepulpandpapermills,amixtureofvirginandrecycledpulpisrapidlybecomingthemostcom-monsourceofpaperandcardboardstockforcommercialconvertedproducts.Themajorityoftheseproductswillbeusedforprinting,rangingfromstationeryletterheadstopaperbagsandboxes(Califor-niaEPA).Examplesoffinishedproductsinclude:

•moldedpulpproducts•cardboardtubes•roofingpaper•corrugatedboxes•paperbags•tissueandtoweling•foldedboxes•cellulosepadding


PROC12

•stationeryandenvelopes•papercupsandliquidcontainers

Operationstomaketheseproductsdonotinvolvethedirectproductionofpulp,butdoinvolvetheprocessingofpapermadefromtheseproducts.Theproductionofproductsfrompaper,cardboardstock,ordrypulprepresentsthetypesofoperationsfoundinmostcities.Majoroperationsmostcommonlyinvolve:

•cuttingandfolding•gluing•coating•printing

Cuttingandfolding,alongwiththehandlingofpaperstockandproducts,isprincipallyadryprocess.FloorcleaningshouldfollowprinciplesoutlinedinthesectiononCleaningandSanitation.Thelastthreeoftheseoperationsinvolvewetorsolventcleaningofsometype.Theadventofwater-solublepaintsandinkshasreducedvolatile-organic-compound(VOC)emissions,buttheuseofwaterasacleaningagentismoreprevalent.Thesameprinciplesusedincleaningequipmentinthefoodandbeverageprocessingindustryapplyhere,withtheadditionofsolventcleaning,whichisstillusedinmanynon-aqueousprint-ing processes:

•Properlyremoveasmuchwasteproductaspossiblebypouringandstoringforfutureuse.•Scrapeequipmentandvesselstoremoveasmuchwasteaspossible.•Usedrybrushes,cloths,andpapertowelstoremovewaste.•Usewettowelsorsolvent-soakedtowels.•Applywaterorsolventonlytoareastobecleaned.

Flexography,gravure,screen-printing,lithography,anddigitalprocessingareallcommonprintingprac-ticesusedtoday.Tohelpsavewater,energy,materials,andtime:

•Designthelayoutofequipmentforeasyaccess.•Ensurethatinkcontainersareeasilysealed.•Providenon-dryingaerosolspraystokeepinkfountainsfromdryingovernight.•Ensurethatpresseshavepropercontrols,suchasautomaticinklevelers.

Water-SavingsPotentialThepracticesdiscussedabovereducewaterusebydecreasingtheamountofcleaningrequiredattheendofthepressrun.Otherwater-savingdesignpracticesarecoveredinthechapteronPhotoandFilmProcessingunderCommercialPrinting.Printingoperationsalsoproducelargeamountsofwasteheatincoolingtheequipment.Largeoperationsoftenhavecoolingtowers.Inthesecases,water-savingtech-niquesoutlinedinthesectiononThermodynamicProcessesshouldbereferenced.

Cost-EffectivenessAnalysisEachcaseisunique,andoverallcostanalysisisnotpossible.However,thewater-savingtechniquesoutlinedabovewillreduceoperationalcostsby:

•reducingwaterandwastewaterbills•reducingpretreatmentcosts•reducingproductloss•reducingchemicaluse•eliminatingwaste


PROC13

RecommendationsManufacturing of Recycled-paper Products

•Properlyremoveasmuchwasteproductaspossiblebypouringandstoringforfutureuse.•Scrapeequipmentandvesselstoremoveasmuchwasteaspossible.

Printing Operations •Designthelayoutoftheequipmenttoprovideeasyaccess.•Providenon-dryingaerosolspraystokeepinkfountainsfromdryingovernight.•Ensurethepresshaspropercontrols,suchasautomaticinklevelers.

See“PhotoandFilmProcessing—CommercialPrinting”foradditionalrecommendations.

ReferencesAlamedaCountyWasteManagementAuthorityandRecyclingBoard.www.stopwaste.org.

CaliforniaEnvironmentalProtectionAgency.California paper, Paperboard and Pulp Mills That Consume Postconsumer Paper. www.ciwmb.ca.gov/Paper/Markets/.

CityofSanJose,California.EnvironmentalServicesDepartment.Best Management Practices to Re-duce Pollution for Printing and Photo processing Operations.

Conservatree. Recycled and Environmental Paper Information.SanFrancisco,California.www.conservatree.com/.

Eco-EfficiencyCentre,The.DalhousieUniversity.2006.Fact Sheet: Eco-Efficiency in the Printing Industry. Dartmouth,NovaScotia.

Kinsella,Susan.Fact Sheet: Buy Recycled Paper!BuyRecycledBusinessAllianceoftheNationalRecyclingCoalition.

Weyerhaeuser.2004.2004 Roadmap for Sustainability. www.weyerhaeuser.com/environment/sustainability/2004.

Metal Finishing

Themetal-finishingindustryoffersmanyopportunitiestoreducebothwater-useandpollution-abate-mentcosts.Theplatingandanodizingprocessesinvolveamulti-tank,multi-stepprocess.Water-savingpractices include:

•drag-outcontrol•goodtankdesign•efficientrinsepractices•processcontrolsandmeters•chemicalrecovery•goodexhaust-hooddesign

Aswithallindustrialandcommercialoperations,efficientcleaningmethodsarekeypracticesthatwillresult in reduced water use.

DescriptionofEndUseTheclassicexampleforthemetal-finishingindustrywasoncetheplatingofcarbumpers(whenchromecarbumperswerestillmanufactured).Theindustryinvolvesmuchmorethanthattoday.Formetals,it


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includeselectroplating,solutionplating,andanodizing,butalsoprintedcircuit(wire)boardandplasticplating.Chrome,zinc,copper,tin,nickel,gold,andsilverareamongthemorecommonmetalsplatedontoobjects.Insomeprocessesobjectsareplatedwithtwolayersofmetals,suchasanunderlayerofcopperfollowedbychrome.

Onecommonprocessinthisindustryisthatpartstobeplatedaremovedsequentiallyfromatreatmenttanktoarinseorwashtanktoanothertreatmenttanktoanotherrinsetank,untilthedesirednumberofplatingstepshavebeenaccomplished.ThephotographfromtheCorpusChristi,Texas,ArmyDepot,whichfollows,illustratesthemulti-tankconfigurationofatypicalmetal-finishingprocess.

Water is used for the following process purposes:•chemicalandplatingsolutionmake-up•rinsing•fume-hoodscrubbing•equipmentcleaning

Corpus Christi Army Depot, Corpus Christi, Texas Advanced Metal Finishing Processes and Facility

(original date: 01/26/1998; revision date: 04/14/2003)


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Thetypicalsequenceforplatinganobjectis:•Cleantheobjectwithbathsthatremoveresidualoilanddirt.• Removerustoroxidationproducts.• Immersetheproductinaplatingbaththroughwhichanelectriccurrentispassed.• Washtheparts.• Eitherhangthepartsbeingplatedfromspeciallydesignedracksorplacetheminperforatedorwovenbasketsor“barrels,”sotheycanbemovedeasilyfromonetanktoanother.

Aschemicalsfromonestepbuildupinthefollowingrinsingtanksorcontaminatetheprocesschemi-cals,watermustbereplaced.Fumesproducedfromallofthetanks,andtheacid(pickling)andplatingprocessesinparticular,mustbesafelyremovedwithfumehoodswhichthenpassthiscontaminatedairtoscrubbersystemstopreventairpollution.Thetypicalconfigurationfortheseprocessesisillustratedon the following page.

Watersavingscanberealizedinsixareas:•Drag-outcontrolinvolvesrecoveringliquidfrompartsbeingprocessedastheyareremovedfromonetank,butbeforetheyenteranother.Themajorreasontodumpwateriscontaminationofarinseorprocesstankwithliquidfromtheprevioustank.Methodsinclude:

» designingracks,baskets,andbarrelssopartsdrainanddonotretainliquids » usingturning,tilting,and“bumping”toremoveexcessliquid » usingdripordrainboardstocollectanddrainliquidsbackintothesourcetank » allowingpartstoremainoverthetankforafewseconds(dwelltime) » washingorblowingcontaminantsbackintoprocessordeadtanksusingfogs,sprays,orairknives

» using wetting agents » usingchemicalsorheattoreduceplating-solutionviscosity » operatingthesolutionsatminimumpossibleconcentration

•Thefollowingtank-designmethodsreducewateruseorallowforbetterreuseandrecoveryofmetals:

» usingairormechanicalagitationtopromotemixingandgoodcontact » hardplumbingallpipingsohosescannotbeleftoninadvertently » preventingshort-circuitingoffluids » sizingtankstotheminimumforthepiecestobeplated » segregatingwastestreamssobothmetalsandwatercanberecoveredmoreeasily

•Efficientrinsingsaveswaterandchemicalsandreduceswastewatercosts.Methodsinvolveseveraltechnologies,including:

» usingspraysonflatpiecesofmetal » counter-currentrinsing,wherethepieceisrinsedinsuccessivelylessconcentratedtanks,withthewaterfromthefirsttankbeingusedasfeedforthesecond,andsoon

» reactiverinsing,wheretherinsewaterfromthefinaltankisusedforthepickle-rinsetankandthepickle-rinsetankwaterisusedasfeedtomakeupthealkaline-rinsetank(seefigurefollowing)

» air agitation of the tanks •Flow-andprocess-controlopportunitiesinclude:

» installingconductivitycontrollerstodischargewateronlyifthechemicalshavebecometoo concentrated

» meteringmakeupwaterforgoodprocesscontrolandtoidentifyproblems » usingflowrestrictorstolimittheamountofwaterbeingadded


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• Chemicalandwaterrecoveryincludesseveralwater-treatmenttechnologies: » filteringplatingfluidtoremovesuspendedmatter » usingmembranetechnologytorecovermetalsandwater » usingROordeionizationforthefeedwaterforbothrinseandprocess-fluidtankstore-duceinterferencefromotherions

» regenerating spent acids » usingRO-rejectwaterforcleanuparound,butnotin,thetanks

•Exhaust-hooddesigncanalsoreducewateruseby: » Recirculatingscrubberliquid » Usingscrubberwateraboveplatingtanksasmake-upwaterforthatprocess » UsingRO-rejectwaterorsimilarrejectstreamsasmake-upwaterforscrubbersforwhich

scrubber effluent will not be reused

Water-SavingsPotentialandCost-SavingExamplesFollowingareexamplesfromrealoperationsofwater-savingprojects,theircosts,andtheirsavings.Becauseofthevariednatureofthissector,eachcasemustbeexaminedseparately,butthebasictech-niqueshaveproveneffectiveto:

•reducewaterandwastewatercosts•reducepretreatmentcosts•reduceenergycosts•reducechemicalcost•increasechemicalandmetalsrecoveryrates•reducelaborcosts

Becauseofthewidevariationinprocessdesignandoperations,asimplecostanalysisisnotpossible.Instead,thefollowingexamplesareprovided:

•Example1—AsmallplatingshopinAustraliathatwasusing360gallonsofwateradayinstalleddrainboardsandadeionizerfor$590.Thecostforservicingthedeionizerisap-proximately$780peryear.Thesemeasurescutwateruseby65,000gallonsayearandsavedover$1,600inchemicalcosteachyearforapaybackof1.3years(EnvironmentalProtectionAgencyofVictoria,Australia).[BaseduponcurrentU.S.dollarsadjustedforinflationandcur-rencyconversionrate.]

•Example2—AlargeindustrialoperationinIllinoisinstalledconductivitycontrollersontwotanks,reducingwateruseinthefirsttankfrom5.0to0.45gpmandinasecondtankfrom2.0to0.5gpm.Thetotalinstalledcostfortheconductivitycontrollersandvalveswas$2,000.Thissavedover3milliongallonsofwaterayear(Brown).

•Example3—AMinnesotamanufacturerinstalledconductivitycontrollersfor$2,100andreducedwaterusebyonemilliongallonsayear(MinnesotaTechnicalAssistanceProgram).


• Metermake-upwaterinnewfacilities.• Employcounter-currentrinsing.• Controldrag-outbyapplyingatleasttwoofthepracticeslistedabove.• Useconductivitycontrollersforrinsetanks.• Installautomaticshutoffonallhoses.• Recirculatewaterand/orusewastestreamsasmakeupwaterforscrubbers.

Additional Practices That Achieve Significant Savings• Employgoodtankdesign.


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• Mixoruseairagitationoftankcontents.• Usmultipledrag-outreductionmethods.• Installfiltrationandwater-treatmentequipment,whereapplicable.• Usereactiverinsing.

ReferencesBrown,Jerry.2000.Pollution Prevention Case Study – Conductivity Controller Technology.TN-72.

Chicago,Illinois.

CH2MHill.May2002.Air Force Water Conservation Guidebook.

DeDeitrich.Electroplating Rinse Practices and Evaporator Sizing. www.ddpsic.com.

DepartmentofPlanningandEnvironmentalProtection.BrowardCounty,Florida.October2003.Pollu-tion Prevention and Best Management Practices for Metal Finishing Facilities.FortLauderdale,Florida.

Donovan,RobertP.,Morrison,DennisJ.,andTimon,RobertP.November1998.Design of Recycling Systems for Spent Rinse Water in Sandia’s Microelectronics Development Laboratory. Interna-tionalSEMATECHTT#98113599A-ENG.

EnvironmentalProtectionAgencyofVictoria,Australia.1993.Waste Minimization—Assessment and Opportunities for Industry. Southbank,Victoria.ISBN07306-2888-4.

MinnesotaTechnicalAssistanceProgram.1997.Hoffman Engineering Saves $32,000 Annually by Reducing Water Use. www.mntap.umn.edu/intem/projects.

NarragansettBayCommission,The.P2 Facts: Industrial Rinse Water Reduction. Providence,RhodeIsland.

NationalCenterforManufacturingScience.2007.Printed Wire Board.PrintedWireBoardResourceCenter.AnnArbor,Michigan.MetalProductsandMachinery(MP&M)PWBSubcategory.www.pwbrc.org/mpmpwb.cfm.

NewMexico.OfficeofStateEngineer. July1999.A Water Conservation Guide for Commercial, Institutional and Industrial Water Users.

NorthCarolina.DepartmentofEnvironmentandNaturalResources.DivisionofPollutionPrevention.August1998.Water Efficiency Manual for Commercial, Industrial, and Institutional Facilities.

Ogunbameru,Gus,Ph.C.,Ch.E.2004.Best Management Practices for Selected Industries and Ad-ditional Resources.MassachusettsOfficeofTechnicalAssistance.

RosemontAnalyticalInc.2003.Water Conservation in Metal Finishing.EmersonProcessManage-ment.Irvine,California.

Thompson,Chris,andLickteig,Edward.October2008.Recycling High Purity Rinsewater at Sam-sung Austin Semiconductor. SamsungAustinSemiconductor.UltrapureWater.Austin,Texas.


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