Water Quality Engineering: Physical / Chemical Treatment Processes PDF
Preview Water Quality Engineering: Physical / Chemical Treatment Processes
WATER QUALITY ENGINEERING WATER QUALITY ENGINEERING Physical/Chemical Treatment Processes MARK M. BENJAMIN DESMOND F. LAWLER Coverdesign:JohnWiley&Sons,Inc. Coverphotograph:CourtesyofBrainHaws Copyright#2013byJohnWiley&Sons,Inc.Allrightsreserved. PublishedbyJohnWiley&Sons,Inc.,Hoboken,NewJersey. PublishedsimultaneouslyinCanada. Nopartofthispublicationmaybereproduced,storedinaretrievalsystem,ortransmittedinanyformorbyanymeans,electronic,mechanical,photocopying, recording,scanning,orotherwise,exceptaspermittedunderSection107or108ofthe1976UnitedStatesCopyrightAct,withouteitherthepriorwritten permissionofthePublisherorauthorizationthroughpaymentoftheappropriateper-copyfeetotheCopyrightClearanceCenter,Inc.,222RosewoodDrive, Danvers, MA 01923, +(978) 750-8400, fax +(978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressedtothePermissionsDepartment,JohnWiley&Sons,Inc.,111RiverStreet,Hoboken,NJ07030,+(201)748-6011,fax+(201)748-6008,or online at http://www.wiley.com/go/permission. LimitofLiability/DisclaimerofWarranty:Whilethepublisherandauthorhaveusedtheirbesteffortsinpreparingthisbook,theymakenorepresentationsor warrantieswithrespecttotheaccuracyorcompletenessofthecontentsofthisbookandspecificallydisclaimanyimpliedwarrantiesofmerchantabilityor fitnessforaparticularpurpose.Nowarrantymaybecreatedorextendedbysalesrepresentativesorwrittensalesmaterials.Theadviceandstrategies containedhereinmaynotbesuitableforyoursituation.Youshouldconsultwithaprofessionalwhereappropriate.Neitherthepublishernorauthorshallbe liableforanylossofprofitoranyothercommercialdamages,includingbutnotlimitedtospecial,incidental,consequential,orotherdamages. Forgeneralinformationonourotherproductsandservicesorfortechnicalsupport,pleasecontactourCustomerCareDepartmentwithintheUnitedStates at+(800)762-2974,outsidetheUnitedStatesat+(317)572-3993orfax+(317)572-4002. Wileyalsopublishesitsbooksinavarietyofelectronicformats.Somecontentthatappearsinprintmaynotbeavailableinelectronicformats.Formore information about Wiley products, visit our web site at www.wiley.com. LibraryofCongressCataloging-in-PublicationData: Benjamin,MarkM. Waterqualityengineering:physical/chemicaltreatmentprocesses/MarkBenjamin,DesmondLawler. pagescm Includesbibliographicalreferencesandindex. ISBN978-1-118-16965-0(cloth) 1. Water—Purification. 2. Sewage—Purification. I. Lawler,DesmondF. II. Title. TD430.B3862013 628.1066–dc23 2012023641 PrintedintheUnitedStatesofAmerica 10 9 8 7 6 5 4 3 2 1 CONTENTS PREFACE xxi ACKNOWLEDGMENTS xxv PARTI REACTORSANDREACTIONSINWATERQUALITY ENGINEERING 1 MassBalances 3 1.1 Introduction:TheMassBalanceConcept, 3 1.2 TheMassBalanceforaSystemwithUnidirectionalFlowand ConcentrationGradient, 7 TheStorageTerm, 8 TheAdvectiveTerm, 10 TheDiffusionandDispersionTerms, 11 TheChemicalReactionTerm, 15 CombiningtheTermsintotheOverallMassBalance, 17 TheDifferentialFormoftheOne-DimensionalMassBalance, 18 1.3 TheMassBalanceforaSystemwithFlowandConcentration GradientsinArbitraryDirections, 20 TheAdvectionTerm, 20 TheDiffusionandDispersionTerms, 21 TheStorageandReactionTerms, 23 TheOverallMassBalance, 23 1.4 TheDifferentialFormoftheThree-DimensionalMassBalance, 24 1.5 Summary, 25 References, 26 Problems, 27 2 ContinuousFlowReactors:HydraulicCharacteristics 29 2.1 Introduction, 29 2.2 ResidenceTimeDistributions, 30 Tracers, 31 PulseInputResponse, 33 v vi CONTENTS StepInputResponse, 35 StatisticsofProbabilityDistributionsandtheMeanHydraulic DetentionTime, 37 2.3 IdealReactors, 42 PlugFlowReactors, 42 PulseInputtoaPFR:FixedFrameofReference(EulerianView), 43 PulseInputtoaPFR:MovingFrameofReference(LagrangianView), 44 ContinuousFlowStirredTankReactors, 45 PulseInputtoaCFSTR, 45 StepinputtoaCFSTR, 47 2.4 NonidealReactors, 48 TracerOutputfromNonidealReactors, 48 RelatingTracerInputandOutputCurvesviatheConvolutionIntegral, 48 ModelingResidenceTimeDistributionsofNonidealReactors, 50 PFRwithDispersion, 50 CFSTRsinSeries, 55 ModelingShort-CircuitingandDeadSpace, 57 PFRsinParallelandSeries:SegregatedFlowandEarlyVersusLate Mixing, 59 NonequivalentCFSTRsinSeries, 62 SimpleIndicesofHydraulicBehavior, 62 2.5 Equalization, 62 FlowEqualization, 63 ConcentrationEqualization, 66 ConcurrentFlowandConcentrationEqualization, 69 2.6 Summary, 70 Appendix2A.IntroductiontoLaplaceTransformsasaMethodofSolving (Certain)DifferentialEquations, 71 ExamplesoftheUseofLaplaceTransforms, 73 References, 73 Problems, 74 3 ReactionKinetics 81 3.1 Introduction, 81 3.2 Fundamentals, 82 Terminology, 82 TheKineticsofElementaryReactions, 84 FrequencyofMolecularCollisions, 84 EnergeticsofMolecularCollisions, 84 TheKineticsofNonelementaryReactions, 87 PowerLawandOtherRateExpressionsforNonelementaryReactions, 88 3.3 KineticsofIrreversibleReactions, 88 TheMassBalanceforBatchReactorswithIrreversibleReactions, 89 TheIntegralMethodofReactionRateAnalysis, 89 AnalysisofReactionHalf-Times, 91 KineticsExpressionsContainingTermsfortheConcentrationsofMore ThanOneReactiveSpecies, 93 TheDifferentialMethodofReactionRateAnalysis, 96 AnalysisofNonpower-LawRateExpressions, 97 CharacteristicReactionTimes, 97 3.4 KineticsofReversibleReactions, 99 ReversibleReactions, 99 CONTENTS vii CharacteristicTimesandLimitingCasesforReversibleReactions, 103 SimplificationofReactionRateExpressionsforLimitingCases, 104 VeryRapidandVerySlowApproachtoEquilibriumasLimiting Cases, 104 ReactionQuotients,Equilibrium,andtheAssumptionof Irreversibility, 105 NearlyCompleteReactionasaLimitingCase, 106 SummaryofLimitingCases, 107 3.5 KineticsofSequentialReactions, 107 TheProgressofConsecutiveReactionsandtheRate-Controlling Step, 108 TheThermodynamicsofSequentialReactions, 111 SteadyState:DefinitionandComparisonwithChemical Equilibrium, 112 3.6 TheTemperatureDependenceoftheRatesofNonelementary Reactions, 114 3.7 Summary, 115 References, 116 Problems, 116 4 ContinuousFlowReactors:PerformanceCharacteristicswithReaction 121 4.1 Introduction, 121 4.2 ExtentofReactioninSingleIdealReactorsatSteadyState, 121 ExtentofReactioninaContinuousFlowStirredTankReactor atSteadyState, 121 First-OrderIrreversibleReactions, 122 Non-First-OrderIrreversibleReactions, 123 ExtentofReactioninaPlugFlowReactoratSteadyState, 123 FixedFrameofReference(EulerianView), 124 MovingFrameofReference(LagrangianView), 125 Irreversiblenth-OrderReactions, 125 ComparisonofCFSTRsandPFRsforIrreversibleReactions, 126 ReversibleReactions, 129 4.3 ExtentofReactioninSystemsComposedofMultipleIdealReactors atSteadyState, 130 PFRsinSeries, 130 CFSTRsinSeries, 130 ApplicationtoChemicalDisinfection, 133 CFSTRsorPFRsinParallel, 135 UsingReactorswithFlowtoDeriveRateExpressions, 135 4.4 ExtentofReactioninReactorswithNonidealFlow, 135 FractionRemainingBasedontheExitAgeDistribution, 136 FractionRemainingBasedontheDispersionModel, 140 SummaryofSteady-StatePerformanceinNonidealReactors, 141 4.5 ExtentofReactionUnderNon-Steady-ConditionsinContinuous FlowReactors, 141 ExtentofConversioninPFRsUnderNon-Steady-StateConditions, 141 ExtentofConversioninCFSTRsUnderNon-Steady-State Conditions, 142 ExtentofConversioninNonidealReactorsUnderNon-Steady-State Conditions, 144 4.6 Summary, 146 References, 147 Problems, 147 viii CONTENTS PARTII REMOVALOFDISSOLVEDCONSTITUENTSFROMWATER 5 GasTransferFundamentals 155 5.1 Introduction, 155 ImportanceofGasTransferinEnvironmentalEngineering, 155 OverviewofGas/LiquidEquilibrium, 155 OverviewofTransportandReactionKineticsinGasTransfer Processes, 157 IncorporatingGasTransferintoMassBalances, 157 ChapterOverview, 158 5.2 TypesofEngineeredGasTransferSystems, 159 5.3 Henry’sLawandGas/LiquidEquilibrium, 162 VolatilizationandDissolutionasaChemicalReaction, 162 PartitionCoefficients,EquilibriumConstants,andtheFormal DefinitionofHenry’sLaw, 162 Dimensionsofc ,c ,andHenry’sLawConstant, 164 L G FactorsAffectingGas/LiquidEquilibrium, 167 5.4 RelatingChangesintheGasandLiquidPhases, 170 5.5 MechanisticModelsforGasTransfer, 170 FluidDynamicsandMassTransportintheInterfacialRegion, 170 TheMassBalanceonaVolatileSpeciesNearaGas/Solution Interface, 171 GasTransferandTransportThroughaFluidPacketatthe Interface, 171 FluxUnderLimiting-CaseScenarios:ShortandLongPacket ResidenceTimes, 174 AccountingforthePacketAgeandPacketResidenceTime Distribution, 175 TheGasTransferCoefficientandItsInterpretation, 175 5.6 TheOverallGasTransferRateCoefficient,K , 179 L TheCombinedResistanceoftheGasandLiquidPhases, 179 ComparingGas-PhaseandLiquid-PhaseResistances, 181 CoupledTransportandReaction, 183 5.7 Evaluatingk ,k ,K ,anda:EffectsofHydrodynamicandOther L G L OperatingConditions, 187 ApproachesforEstimatingGasTransferRateCoefficients, 188 Gas-in-LiquidSystems, 188 Liquid-in-GasSystems, 192 EffectsofOtherParametersonGasTransferRateConstants, 195 Temperature, 195 SolutionChemistry, 196 5.8 Summary, 196 Appendix5A.ConventionsUsedforConcentrationsandActivity CoefficientsWhenComputingHenry’sConstants, 197 Overview, 197 ConventionsforthePhysicochemicalEnvironmentintheStandard State, 198 Appendix5B.DerivationoftheGasTransferRateExpressionforVolatile SpeciesThatUndergoRapidAcid/BaseReactions, 199 References, 202 Problems, 204
The list of books you might like
