Anaerobic Reactors

188 Pages·2007·2.02 MB·English

Anaerobic Reactors
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 FOUR
Anaerobic Reactors
Carlos Augusto de Lemos Chernicharo
DepartmentofSanitaryandEnvironmentalEngineering
FederalUniversityofMinasGerais,Brazil
PublishedbyIWAPublishing,AllianceHouse,12CaxtonStreet,LondonSW1H0QS,UK
Telephone:[phone];Fax:[phone];Email:[email protected]
Website:www.iwapublishing.com
Firstpublished2007
(cid:1)C 2007IWAPublishing
Copy-editedandtypesetbyAptaraInc.,NewDelhi,India
PrintedbyLightningSource
Apartfromanyfairdealingforthepurposesofresearchorprivatestudy,orcriticismorreview,as
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bereproduced,storedortransmittedinanyformorbyanymeans,withoutthepriorpermissionin
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addressprintedabove.
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informationcontainedinthisbookandcannotacceptanylegalresponsibilityorliabilityforerrorsor
omissionsthatmaybemade.
Disclaimer
TheinformationprovidedandtheopinionsgiveninthispublicationarenotnecessarilythoseofIWA
oroftheeditors,andshouldnotbeacteduponwithoutindependentconsiderationandprofessional
advice.IWAandtheeditorswillnotacceptresponsibilityforanylossordamagesufferedbyany
personactingorrefrainingfromactinguponanymaterialcontainedinthispublication.
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ISBN:1843391643
ISBN13:9781843391647
Contents
Preface vii
Theauthor xi
1 Introductiontoanaerobictreatment 1
1.1 Applicabilityofanaerobicsystems 1
1.2 Positiveaspects 2
2 Principlesofanaerobicdigestion 5
2.1 Introduction 5
2.2 Microbiologyofanaerobicdigestion 6
2.3 Biochemistryofanaerobicdigestion 9
2.4 Environmentalrequirements 23
3 Biomassinanaerobicsystems 39
3.1 Preliminaries 39
3.2 Biomassretentioninanaerobicsystems 39
3.3 Evaluationofthemicrobialmass 42
3.4 Evaluationofthemicrobialactivity 44
4 Anaerobictreatmentsystems 51
4.1 Preliminaries 51
4.2 Conventionalsystems 52
4.3 High-ratesystems 58
4.4 Combinedtreatmentsystems 68
5 Designofanaerobicreactors 70
5.1 Anaerobicfilters 70
5.2 Upflowanaerobicsludgeblanketreactors 82
v
vi Contents
6 Operationalcontrolofanaerobicreactors 116
6.1 Importanceofoperationalcontrol 116
6.2 Operationalcontrolofthetreatmentsystem 119
6.3 Start-upofanaerobicreactors 133
6.4 Operationaltroubleshooting 141
7 Post-treatmentofeffluentsfromanaerobicreactors 147
7.1 Applicabilityandlimitationsoftheanaerobictechnology 147
7.2 Mainalternativesforthepost-treatmentofeffluentsfrom
anaerobicreactors 152
References 169
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,
vii
viii Preface
as a result of the higher technological input and mechanisation level. The main
purposeofthisseriesofbooksistopresentthetechnologiesforurbanwastewater
treatmentasappliedtothespecificconditionofwarmtemperature,withtherelated
implicationsintermsofdesignandoperation.Thereisnostrictdefinitionforthe
rangeoftemperaturesthatfallintothiscategory,sincethebooksalwayspresent
howtocorrectparameters,ratesandcoefficientsfordifferenttemperatures.Inthis
sense,subtropicalandeventemperateclimatearealsoindirectlycovered,although
mostofthefocusliesonthetropicalclimate.
Another important point is that most warm climate regions are situated in
developing countries. Therefore, the books cast a special view on the reality of
thesecountries,inwhichsimple,economicalandsustainablesolutionsarestrongly
demanded.Alltechnologiespresentedinthebooksmaybeappliedindeveloping
countries,butofcoursetheyimplydifferentrequirementsintermsofenergy,equip-
mentandoperationalskills.Wheneverpossible,simplesolutions,approachesand
technologiesarepresentedandrecommended.
Consideringthedifficultyincoveringalldifferentalternativesforwastewater
collection, the books concentrate on off-site solutions, implying collection and
transportation of the wastewater to treatment plants. No off-site solutions, such
aslatrinesandseptictanksareanalysed.Also,strongerfocusisgiventoseparate
sewerage systems, although the basic concepts are still applicable to combined
and mixed systems, especially under dry weather conditions. Furthermore, em-
phasis is given to urban wastewater, that is, mainly domestic sewage plus some
additional small contribution from non-domestic sources, such as industries.
Hence,thebooksarenotdirectedspecificallytoindustrialwastewatertreatment,
giventhespecificitiesofthistypeofeffluent.Anotherspecificviewofthebooks
is that they detail biological treatment processes. No physical-chemical wastew-
atertreatmentprocessesarecovered,althoughsomephysicaloperations,suchas
sedimentationandaeration,aredealtwithsincetheyareanintegralpartofsome
biologicaltreatmentprocesses.
The books’ proposal is to present in a balanced way theory and practice of
wastewater treatment, so that a conscious selection, design and operation of the
wastewater treatment process may be practised. Theory is considered essential
fortheunderstandingoftheworkingprinciplesofwastewatertreatment.Practice
isassociatedtothedirectapplicationoftheconceptsforconception,designand
operation.Inordertoensurethepracticalanddidacticviewoftheseries,371illus-
trations,322summarytablesand117examplesareincluded.Allmajorwastewater
treatmentprocessesarecoveredbyfullandinterlinkeddesignexampleswhichare
builtupthroughouttheseriesandthebooks,fromthedeterminationofthewaste-
watercharacteristics,theimpactofthedischargeintoriversandlakes,thedesign
ofseveralwastewatertreatmentprocessesandthedesignofthesludgetreatment
anddisposalunits.
The series is comprised by the following books, namely: (1) Wastewater
characteristics,treatmentanddisposal;(2)Basicprinciplesofwastewatertreat-
ment;(3)Wastestabilisationponds;(4)Anaerobicreactors;(5)Activatedsludge
andaerobicbiofilmreactors;(6)Sludgetreatmentanddisposal.
Preface ix
Volume 1 (Wastewater characteristics, treatment and disposal) presents an
integrated view of water quality and wastewater treatment, analysing waste-
water characteristics (flow and major constituents), the impact of the discharge
into receiving water bodies and a general overview of wastewater treatment and
sludgetreatmentanddisposal.Volume1ismoreintroductory,andmaybeusedas
teachingmaterialforundergraduatecoursesinCivilEngineering,Environmental
Engineering,EnvironmentalSciencesandrelatedcourses.
Volume2(Basicprinciplesofwastewatertreatment)isalsointroductory,but
at a higher level of detailing. The core of this book is the unit operations and
processesassociatedwithbiologicalwastewatertreatment.Themajortopicscov-
ered are: microbiology and ecology of wastewater treatment; reaction kinetics
and reactor hydraulics; conversion of organic and inorganic matter; sedimenta-
tion; aeration. Volume 2 may be used as part of postgraduate courses in Civil
Engineering, Environmental Engineering, Environmental Sciences and related
courses, either as part of disciplines on wastewater treatment or unit operations
andprocesses.
Volumes3to5arethecentralpartoftheseries,beingstructuredaccordingto
the major wastewater treatment processes (waste stabilisation ponds, anaerobic
reactors,activatedsludgeandaerobicbiofilmreactors).Ineachvolume,allmajor
processtechnologiesandvariantsarefullycovered,includingmainconcepts,work-
ing principles, expected removal efficiencies, design criteria, design examples,
constructionaspectsandoperationalguidelines.SimilarlytoVolume2,volumes
3 to 5 can be used in postgraduate courses in Civil Engineering, Environmental
Engineering,EnvironmentalSciencesandrelatedcourses.
Volume 6 (Sludge treatment and disposal) covers in detail sludge charac-
teristics, production, treatment (thickening, dewatering, stabilisation, pathogens
removal) and disposal (land application for agricultural purposes, sanitary land-
fills,landfarmingandothermethods).Environmentalandpublichealthissuesare
fullydescribed.Possibleacademicusesforthispartaresameasthosefromvolumes
3to5.
Besides being used as textbooks at academic institutions, it is believed that
the series may be an important reference for practising professionals, such as
engineers,biologists,chemistsandenvironmentalscientists,actinginconsulting
companies,waterauthoritiesandenvironmentalagencies.
Thepresentseriesisbasedonaconsolidated,integratedandupdatedversionofa
seriesofsixbookswrittenbytheauthorsinBrazil,coveringthetopicspresentedin
thecurrentbook,withthesameconcernfordidacticapproachandbalancebetween
theoryandpractice.ThelargesuccessoftheBrazilianbooks,usedatmostgraduate
andpost-graduatecoursesatBrazilianuniversities,besidesconsultingcompanies
andwaterandenvironmentalagencies,wasthedrivingforceforthepreparation
ofthisinternationalversion.
Inthisversion,thebooksaimatpresentingconsolidatedtechnologybasedon
worldwideexperienceavailableattheinternationalliterature.However,itshould
berecognisedthatasignificantinputcomesfromtheBrazilianexperience,consid-
eringthebackgroundandworkingpracticeofallauthors.Brazilisalargecountry
x Preface
with many geographical, climatic, economical, social and cultural contrasts,
reflecting well the reality encountered in many countries in the world. Besides,
itshouldbementionedthatBraziliscurrentlyoneoftheleadingcountriesinthe
worldontheapplicationofanaerobictechnologytodomesticsewagetreatment,
andinthepost-treatmentofanaerobiceffluents.Regardingthispoint,theauthors
would like to show their recognition for the Brazilian Research Programme on
Basic Sanitation (PROSAB), which, through several years of intensive, applied,
cooperative research has led to the consolidation of anaerobic treatment and
aerobic/anaerobicpost-treatment,whicharecurrentlywidelyappliedinfull-scale
plantsinBrazil.ConsolidatedresultsachievedbyPROSABareincludedinvarious
partsofthebook,representinginvaluableandupdatedinformationapplicableto
warmclimateregions.
Volumes1to5werewrittenbythetwomainauthors.Volume6countedwiththe
invaluable participation of Cleverson Vitorio Andreoli and Fernando Fernandes,
who acted as editors, and of several specialists, who acted as chapter authors:
Aderlene Ineˆs de Lara, Deize Dias Lopes, Dione Mari Morita, Eduardo Sabino
Pegorini, Hilton Fel´ıcio dos Santos, Marcelo Antonio Teixeira Pinto, Maur´ıcio
Luduvice, Ricardo Franci Gonc¸alves, Sandra Ma´rcia Cesa´rio Pereira da Silva,
VaneteThomazSoccol.
Many colleagues, students and professionals contributed with useful sugges-
tions, reviews and incentives for the Brazilian books that were the seed for this
internationalversion.Itwouldbeimpossibletolistallofthemhere,butourheart-
feltappreciationisacknowledged.
The authors would like to express their recognition for the support provided
by the Department of Sanitary and Environmental Engineering at the Federal
UniversityofMinasGerais,Brazil,atwhichthetwoauthorswork.Thedepartment
providedinstitutionalandfinancialsupportforthisinternationalversion,whichis
in line with the university’s view of expanding and disseminating knowledge to
society.
Finally,theauthorswouldliketoshowtheirappreciationtoIWAPublishing,for
theirincentiveandpatienceinfollowingthedevelopmentofthisseriesthroughout
theyearsofhardwork.
MarcosvonSperling
CarlosAugustodeLemosChernicharo
December2006