Waste Stabilisation Ponds BiologicalWastewaterTreatmentSeries TheBiologicalWastewaterTreatmentseriesisbasedonthebookBiological WastewaterTreatmentinWarmClimateRegionsandonahighlyacclaimedsetof bestsellingtextbooks.Thisinternationalversioniscomprisedbysixtextbooks givingastate-of-the-artpresentationofthescienceandtechnologyofbiological wastewatertreatment. TitlesintheBiologicalWastewaterTreatmentseriesare: Volume1:WastewaterCharacteristics,TreatmentandDisposal Volume2:BasicPrinciplesofWastewaterTreatment Volume3:WasteStabilisationPonds Volume4:AnaerobicReactors Volume5:ActivatedSludgeandAerobicBiofilmReactors Volume6:SludgeTreatmentandDisposal Biological Wastewater Treatment Series VOLUME THREE Waste Stabilisation Ponds Marcos von Sperling DepartmentofSanitaryandEnvironmentalEngineering FederalUniversityofMinasGerais,Brazil PublishedbyIWAPublishing,AllianceHouse,12CaxtonStreet,LondonSW1H0QS,UK Telephone:+44(0)2076545500;Fax:+44(0)2076545555;Email:[email protected] Website:www.iwapublishing.com Firstpublished2007 (cid:1)C 2007IWAPublishing Copy-editedandtypesetbyAptaraInc.,NewDelhi,India PrintedbyLightningSource Apartfromanyfairdealingforthepurposesofresearchorprivatestudy,orcriticismorreview,as permittedundertheUKCopyright,DesignsandPatentsAct(1998),nopartofthispublicationmay bereproduced,storedortransmittedinanyformorbyanymeans,withoutthepriorpermissionin writingofthepublisher,or,inthecaseofphotographicreproduction,inaccordancewiththetermsof licencesissuedbytheCopyrightLicensingAgencyintheUK,orinaccordancewiththetermsof licensesissuedbytheappropriatereproductionrightsorganizationoutsidetheUK.Enquiries concerningreproductionoutsidethetermsstatedhereshouldbesenttoIWAPublishingatthe addressprintedabove. Thepublishermakesnorepresentation,expressedorimplied,withregardtotheaccuracyofthe informationcontainedinthisbookandcannotacceptanylegalresponsibilityorliabilityforerrorsor omissionsthatmaybemade. Disclaimer TheinformationprovidedandtheopinionsgiveninthispublicationarenotnecessarilythoseofIWA oroftheeditors,andshouldnotbeacteduponwithoutindependentconsiderationandprofessional advice.IWAandtheeditorswillnotacceptresponsibilityforanylossordamagesufferedbyany personactingorrefrainingfromactinguponanymaterialcontainedinthispublication. BritishLibraryCataloguinginPublicationData ACIPcataloguerecordforthisbookisavailablefromtheBritishLibrary LibraryofCongressCataloguing-in-PublicationData AcataloguerecordforthisbookisavailablefromtheLibraryofCongress ISBN:1843391635 ISBN13:9781843391630 Contents Preface ix Theauthor xiii 1 Overviewofstabilisationponds 1 2 Facultativeponds 8 2.1 Introduction 8 2.2 Descriptionoftheprocess 9 2.3 Influenceofalgae 11 2.4 Influenceofenvironmentalconditions 14 2.5 Designcriteria 18 2.6 EstimationoftheeffluentBODconcentration 24 2.7 Pondarrangements 38 2.8 Sludgeaccumulation 39 2.9 Operationalcharacteristics 40 2.10 Polishingofpondeffluents 40 3 Systemofanaerobicpondsfollowedbyfacultativeponds 46 3.1 Introduction 46 3.2 Descriptionoftheprocess 47 3.3 Designcriteriaforanaerobicponds 48 3.4 EstimationoftheeffluentBODconcentrationfromthe anaerobicpond 51 3.5 Designoffacultativepondsfollowing anaerobicponds 53 3.6 Sludgeaccumulationinanaerobicponds 53 v vi Contents 4 Facultativeaeratedlagoons 58 4.1 Introduction 58 4.2 Descriptionoftheprocess 58 4.3 Designcriteria 59 4.4 EstimationoftheeffluentBODconcentration 60 4.5 Oxygenrequirements 63 4.6 Aerationsystem 64 4.7 Powerrequirements 64 4.8 Sludgeaccumulation 66 5 Complete-mixaeratedlagoonsfollowedbysedimentationponds 70 5.1 Introduction 70 5.2 Descriptionoftheprocess 71 5.3 Designcriteriaforthecomplete-mixaeratedlagoons 72 5.4 EstimationoftheeffluentBODconcentrationfromthe aeratedlagoon 73 5.5 Oxygenrequirementsintheaeratedlagoon 75 5.6 Powerrequirementsintheaeratedlagoon 76 5.7 Designofthesedimentationpond 76 6 Removalofpathogenicorganisms 84 6.1 Introduction 84 6.2 Processdescription 84 6.3 Estimationoftheeffluentcoliformconcentration 85 6.4 Qualityrequirementsfortheeffluent 96 6.5 Designcriteriaforcoliformremoval 98 6.6 Removalofhelmintheggs 110 7 Nutrientremovalinponds 116 7.1 Nitrogenremoval 116 7.2 Phosphorusremoval 121 8 Pondsforthepost-treatmentoftheeffluentfrom anaerobicreactors 123 9 Constructionofstabilisationponds 127 9.1 Introduction 127 9.2 Locationoftheponds 127 9.3 Deforestation,cleaningandexcavationofthesoil 129 9.4 Slopes 129 9.5 Bottomoftheponds 132 9.6 Inletdevices 133 9.7 Outletdevices 136 10 Maintenanceandoperationofstabilisationponds 138 10.1 Introduction 138 10.2 Operationalstaff 139 10.3 Inspection,samplingandmeasurements 139 Contents vii 10.4 Operationstart-up 139 10.5 Operationalproblems 144 11 Managementofthesludgefromstabilisationponds 150 11.1 Preliminaries 150 11.2 Characteristicsanddistributionofthesludgein stabilisationponds 151 11.3 Removalofsludgefromstabilisationponds 152 References 159 Preface The present series of books has been produced based on the book “Biological wastewatertreatmentinwarmclimateregions”,writtenbythesameauthorsand also published by IWA Publishing. The main idea behind this series is the sub- division of the original book into smaller books, which could be more easily purchasedandused. Theimplementationofwastewatertreatmentplantshasbeensofarachallenge formostcountries.Economicalresources,politicalwill,institutionalstrengthand cultural background are important elements defining the trajectory of pollution control in many countries. Technological aspects are sometimes mentioned as being one of the reasons hindering further developments. However, as shown in this series of books, the vast array of available processes for the treatment of wastewater should be seen as an incentive, allowing the selection of the most appropriate solution in technical and economical terms for each community or catchmentarea.Foralmostallcombinationsofrequirementsintermsofeffluent quality,landavailability,constructionandrunningcosts,mechanisationleveland operationalsimplicitytherewillbeoneormoresuitabletreatmentprocesses. Biologicalwastewatertreatmentisverymuchinfluencedbyclimate.Tempera- tureplaysadecisiveroleinsometreatmentprocesses,especiallythenatural-based and non-mechanised ones. Warm temperatures decrease land requirements, en- hanceconversionprocesses,increaseremovalefficienciesandmaketheutilisation of some treatment processes feasible. Some treatment processes, such as anaer- obic reactors, may be utilised for diluted wastewater, such as domestic sewage, onlyinwarmclimateareas.Otherprocesses,suchasstabilisationponds,maybe appliedinlowertemperatureregions,butoccupyingmuchlargerareasandbeing subjected to a decrease in performance during winter. Other processes, such as activatedsludgeandaerobicbiofilmreactors,arelessdependentontemperature, ix