英文文献Word格式.docx
- 文档编号:21596455
- 上传时间:2023-01-31
- 格式:DOCX
- 页数:7
- 大小:21.13KB
英文文献Word格式.docx
《英文文献Word格式.docx》由会员分享,可在线阅读,更多相关《英文文献Word格式.docx(7页珍藏版)》请在冰豆网上搜索。
wastewater;
treatment;
nitrogenremoval;
phosphorusremoval;
reversedA2/Oprocess
PrincipleandCharacteristicsofReversedA2/OProcess
Conventionalbiologicalnitrogenandphosphorusremovalprocessisanaerobic(A1)/hypoxia(A2)/aerobic(O)layout.Thelayoutofthetheorybasedonanunderstandingthat:
Polyeffectivemicrobialphosphoruslevelsofphosphorusrelease,fullyornot,toimprovethephosphorusremovalcapacityisoftheutmostimportance,anaerobiczonesothattheformercanmicrobialpolymerandcarbonpriorityfullphosphorusrelease.However,theexistenceofinnerloop,Conventionaltechnologysystemsemitresidualsludgeactuallyonlyasmallpartofacompleteexperiencephosphorusrelease,theuptakeprocess,therestwerebasicallyanaerobicstatewithoutdirectaccessfromanoxicandaerobiczone,whichisdetrimentaltothephosphorus
Becauseofthelackofoxygenislocatedinthecentralsystem,denitrificationcarbonallocationinanunfavorableposition,Itwillaffectthenitrogenremovalsystem;
Asanaerobicresidents,SludgebacktotheanaerobiczonenitratehaveanegativeimpactonInordertoavoidtheimpactofthedevelopmentofsomenewtechnology(suchasApplicationofUCTWell,etc.)tendstocomplicate;
actualoperatingexperienceshowsthatAccordingtoanaerobic-aerobictwodenitrificationprocessdesignsystemisalsooftenagoodphosphorusremovalcapacity.Therefore,theconventionalbiologicalnitrogenandphosphorusremovalprocess(A1/A2/O)layoutreasonableworthfurtherexploration
1MaterialsandMethods
ActivatedSludgefromsewagebiologicalnitrogenandphosphorusremovalsmall-scaletestsystem,thesewagefromtheactualcitysewage.ThetableofSewagesludgeandthenature
Table1sewagesludgeandthenature
Sewage
Sludge
COD(mg/L)
400-800
MLSS(g/L)
3.0-4.0
BOD5(mg/L)
50-450
VSS/SS
0.60-0.64
TN(mg/L)
45-65
N(mgN/gVSS)
110-130
TP(mg/L)
2.5-10.0
P(mgN/gVSS)
48-60
VFA(mg/L)
25-173
SVI
180-230
2Testresultsanddiscussion
2.1Short-termanaerobicenvironmentanditsphosphateaccumulatingbacteriatotheimpact
Short-termanaerobicenvironmentinthebiologicalnitrogenandphosphorusremovalsystemplaysakeyroleThepurposeoftestingistoinvestigatetheshort-termanaerobicenvironmentandbiochemicalcharacteristicsofphosphateaccumulatingbacteriaexplainedthattheuptakebehavior.
1)Atrialoftwoidenticalplexiglasscolumn,30wereeffectivesizeL(seefigure1).-Withacentralaxistogetherwiththerotationofthree-dimensionalelasticfiller,nottwo-packing,mixingimpeller.Motorspeedfor15-20min,thecolumnareprovidedtocover.
Columnforalinkmembraneoperation,HRT=20~30h,thetemperatureof24~29℃.Toseparatestudyofurbansewageinshort-termanaerobicenvironmentsewageVFAchanges,Theintroductionofsmallpilotdidnottesttheactivatedsludgesystem.Columnexclusivelyforanaerobicmicrobialenvironmentfromsewagenaturalgrowthupvaccinationorfacultativeanaerobicbacteria.Clearly,anaerobicthangeneralnitrogenandphosphorusremovalsystemmorefullyanaerobiczone.Column2asacontrast,theabsenceofanytreatment.Aformaltestofthetwo-instantaneousleftempty,andfreshsewage,thenstartthemotor,samplingevery2hours,AnalysisofsewageVFAwiththechangesoftime,
Intheexperimentalconditions,short-termanaerobicenvironmentandnotincreasethesewagecapacityVFA,AnaerobicplacedinthedistrictwillfilltheareaVFAincreasedconsumption.
Underanaerobicdigestiontheory,SewageoforganicmacromoleculesintoVFArequireshydrolysisandacid(hydrogenproduction)2process.Whileearlierstudieshaveconsideredinthisprocessandbacteriabelongingtodominantspecies,Butonthelifeofsewagesludgedigestionofthatfact,theoppositeistrue.theanaerobicbacteriaandbacteriathanover100times.Generallyspeaking,themostimportanthydrolysisandfermentationreactionsarethroughtheanaerobicbacteria.Moreover,duetotheanaerobicbacteriabiochemicalinefficient,theprocesstakeslongerhydraulicretentiontime.AndrewsandPearson(1965)havemadeuseofsolubleorganicandinorganicsynthesissewageontheanaerobicVFAfermentationprocessdynamicshavebeenstudied,theresultsindicatethatWhenHRT2.5dreactoratthehighestconcentrationofVFA.
ThetestusedbytheHRT=2~3h(withanaerobicbiologicalphosphorusremovalprocesssimilartotheHRT).only500mg/LCODsewagearound.Insuchconditions,columnisinfactverydifficulttocreateasimilarkindofsludgedigestionanaerobicenvironmentandcultivatingalargetertiaryanaerobes,MicrobialbiofilmonthemainconsumptionremainstheVFAandbacteria,andhadoneoftheVFA-volumedidnotincrease,Insteadconsumptionsoon.Column2exclusivelyforsewageanditssmallnumberofmicroorganisms,theirVFAinaverylongtimeremainedessentiallyconstant.Onlyafteracertainperiodoftime,withtheproliferationofmicroorganisms,VFAdeclineonlynoticeabledecline.Thistestshowsthaturbansewageofgeneralterms,short-termanaerobicsewagedistrictwillnotincreasetheamountofVFA.
2)Ofacolumn,column2leftempty,andsmalltestsystemfromtheendofaerobicDistrict3Lmixture,3Lwithamixtureofsewageintotwoseparatelytoapackedcolumn,column2,thenstartthemotor;
Anaerobictwo-run2-3hafterremovalfillersandimpellers.Aerationandatthesametimeintothestateevery30hsamplinganalysistwo-phosphorusrelease.Uptakecharacteristicsatdifferenttimesusingtheactualsewagefourgrouprepeatabilitytest.Astheactualchangesinsewagewater,thesewageconcentrationoftheVFAweredropped.
Show:
underanaerobicconditionsinfluentVFAhigher,column1,column2ofthegreateramountofphosphorusrelease,andtheunderstandingofthepastisthesame.-Abiofilmexistenceandnature,aresultofanaerobicenvironment-twomorethanthefull.WhentheVFAmore,theORPlow-levelpromptedaphosphateaccumulatingbacteriaatafasterratetoabsorbVFAPHB,Meanwhilereleasephosphate.Thefigureshowsthatanearly-phosphorusreleaseratewassignificantlygreaterthan2column.Figure3(d)influentVFAminimum,acolumnphosphorusreleasecurvehasbeeninthetop-twountiltheendoftheanaerobic,Post-2andP-curvebeforeanintersection.Butafacultative-biofilmwhileconsumptionVFA,whenthereactorVFAinsufficient,facultativebiofilmandphosphateaccumulatingbacteriatoVFAcompetitiononthesurface,make-arapidrateofphosphatereleaseattenuation.Column2isbasicallynon-existentcompetition,Thereforephosphateaccumulatingbacteriacanlongmaintainahigherrateofphosphorusandeventuallyreleasethetotalamountofphosphorusoveracolumn.InadditionFigure3(d),addingacolumnfillertotalphosphorusthan-twosmall,VFAandthehighertheinfluentmoreobviousdifference,seeFigure3(a,b).Inthefollow-upaerobicconditions,apoly-phosphateuptakefromexcessivecapacitythan-2,Whenanaerobiclasted3hoursreducedbytwohoursofthisdifferenceincreasesmarkedly,
Thephenomenonisworthyofspecialattention,anditshowsphosphateaccumulatingbacteriaanaerobiceffectivephosphorusrelease,fullyornot,isnottodeterminetheiraerobiccapacityexcessiveuptakeofnecessaryandsufficientconditions.Thispopularphosphateaccumulatingbacteriaontheanaerobiceffectivephosphorusrelease,thehighertheirexcessiveuptakeofthemoreawarenessisbasicallycontradictory.FromtheaboveanalysisofthephenomenontopromoteaerobicbacteriaPolyexcessivephosphorusuptakemoredynamicnaturecanbedrawnfromthejudgment,toacertainextent,phosphateaccumulatingbacteriaintheanaerobicenvironmentlastedlongerandtheenvironmentORPlowerpromoteaerobicuptakegreaterimpetus.Andtheeffectsofphosphorus,phosphorusreleasemaynotbelongtoafullyequippedinthefaceofnecessity.Aerobicuptakeofenergyfromthecellscanbestoredcarbon(PHB),canbeobtainedfromothersources.Whenthisdifferencebyanaerobiclasted3hoursreducedto2hoursbecomeparticularlyevidentshowanaerobicenvironmentforexcessivemicrobialuptakeofutmostimportance.
2.2Anaerobic,anoxicenvironmentinversionofphosphateaccumulatingbacteriaimpact
Usingtwoidenticalgeometryplexiglasscolumnexperiments,intheeffectivevolumewas30L,Ihavethebottomsampling.Itsanaerobic,anoxicmodeusesafigure(column2)shownintheremovablemixingimpeller,Motorspeedof2.0ning.Aerobicstatebyaerationaeratedfirstbegantesting,testsystemsfromsmallaerobicareafromtheendofthemixtureof3L,3Lwithamixtureofsewage,alanddividedintotwocolumnswereinsertedintotwo.-AmomentoftheinitialKNO3addanotherappropriatesolution,thenstartthemotorrespectivelytothelackofoxygen,anaerobicstateof
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 英文 文献