反硝化滤池不同厂商比较Ch3

DENITRIFICATIONFILTERS:ACOMPARISONOFMANUFACTURERSANDREVIEWOFPERFORMANCE,PATENTANDBIDDINGISSUESC.deBarbadillo(1),M.Lambert,D.Parker,W.Wells,R.WilletBlack&Veatch,8520CliffCameronDrive,Suite350,Charlotte,NC28269反硝化滤池：厂商比较、性能考察、专利及招标问题(2004年WEFTEC)作者：C.deBarbadillo,M,Lambert,D.Parker,W.Wells,R.Willet博莱克•威奇(Black&Veatch)国际咨询公司地址：北卡莱罗纳州夏洛特市CliffCameronDrive大街8520号350大楼ABSTRACTWiththedevelopmentoftotalmaximumdailyloadsfornutrientdischargestoaddresswaterqualityconcerns,manywastewatertreatmentplantsarefacingstringentnutrientlimits.Deepbeddenitrificationfiltersareawell-proventechnologyformeetinglowtotalnitrogenlimits.Concurrentdenitrificationandsolidsremovalinadeep-bedfilterwasfirstpatentedin1973,andthenfollowedbyaseriesofpatentsforothercomponentsincludingtheuseofbackwashwatertoreleasenitrogengas.DravoCorporation,andlaterTetraProcessTechnologies/SevernTrentServices,pioneeredthedevelopmentofdenitrificationfiltertechnologyandcontinuestomakeadvances.Withtheexpirationoftheoriginalprocesspatents,severalotherfiltermanufacturersaredevelopingadenitrificationoptionfortheirequipment.WhileTetra’sdenitrificationexperienceisunparalleled,therearetimeswhenanalternatemustbeconsidered,suchasunderstrictcompetitivebiddinglawsorupgradingexistingfiltersfordenitrification.Thispaperwillprovidealiteraturereviewdocumentingtechnologydevelopmentandprocessperformance;reviewthecurrentmanufacturers,patentedfeaturesandtheirrelevance;andexaminehowbiddingrequirementshavebeenmetinseveralstates.摘要随着每天营养物排放总量的增加，日益引起人们对水质的关注，许多污水处理厂正面临严格的营养物排放限制标准。深床反硝化滤池是一种业已证明可满足较低总氮TN排放要求的可靠技术。通过深床反硝化滤池可同时进行反硝化脱氮及固体物SS去除，这一技术最初于1973年获得专利，随后滤池的其它组件也不断获得了专利，如利用滤后水反冲以释放氮气等技术。Dravo公司即后来的Tetra/水环纯STS水务集团引导了反硝化过滤技术的发展并不断在这一领域取得进步。随着最初的工艺专利期限到期，数家其他过滤池厂商也正在开发反硝化功能。尽管Tetra/STS的反硝化技术具有其独特的竞争力，但是在严格的竞争性招标法规要求下及升级改造老的过滤池以增加其反硝化功能的情况下，还须考虑其他的可能性技术。本文将就技术发展及工艺性能进行文献综述，阐述当前的过滤池厂商、专利及其相关情况，并探讨在几个州内如何满足招标要求。KEYWORDS:denitrificationfilters,tertiarydenitrification,downflowfilters,upflowfilters关键词：反硝化滤池；三级反硝化；降流式过滤池；升流式过滤池INTRODUCTIONThereareanumberoftertiaryfixedfilmdenitrificationprocesseslooselygroupedundertheterm“denitrificationfilters”.TheseincludebiologicalfilterssuchasUSFilter/Kruger’sBiostyrandOndeoDegremont’sBioforaswellasbothupflowanddownflowfiltersthatcanbeappliedforsolidsremovalonlyaswellassupportingtertiarydenitrification.Thispaperwillfocusonlyonfilterswhichcanachievefiltrationinadditiontodenitrification.TheseincludeSevernTrent/TetraProcessTechnologiesDenite®,F.B.Leopoldelimi-NITE®,USFilterDavcodownflowfilter,ParksonDynaSand®,andPaques/USFilterAstrasand®.导言“反硝化滤池”这一术语大致涵盖了数种三级固定膜反硝化工艺，包括美国USFilter公司/瑞士科禄格公司（Kruger）的Biostyr生物滤池、法国得利满公司（OndeoDegremont）的Biofor生物滤池，以及那些前置式升流式和降流式仅用于SS去除或也有三级反硝化功能的各种滤池。本文将主要探讨后置式能同时达到过滤效果以及反硝化脱氮的过滤池，包括SevernTrent/Tetra的Denite®，F.B.Leopold的elimi-NITE®，USFilter公司的Davco等降流式过滤池，Parkson公司的DynaSand®及Paques/USFilter的Astrasand®活性砂升流式滤池。TypesofFilters过滤池类型Thereareanumberofwellestablishedfiltrationoptionsforsolidsremovalatwastewaterplants.Forfiltersthatareoperatedforbothsolidsremovalanddenitrification,therearetwomainconfigurationoptions–conventionaldownflowfilterandupflowcontinuousbackwashfilters.Forfiltrationingeneral,thereareanumberofmanufacturersforbothtypesoffilters.However,onlyafewhavedevelopedtheirfiltersfortertiarydenitrificationasdiscussedherein.Thedownflowdenitrificationfiltersoperateinaconventionaldownflowfiltrationmode,andconsistofunderdrainsupportedgravelandsand.Backwashingandairscouringequipmentareprovided.Nitrogenreleasecyclestoremovenitrogengasbubblesthataccumulateinthemediaalsoarerequired.Filtersmustbebrieflytakenoutofserviceatregularintervalsforashortbackwashingcycle.Upflowcontinuousbackwashfiltersoperateinanupflowmode.Thesandbedisslowlydrawndownwardintoanairliftsystemwhichscoursthemediaandcoveysitbacktothetopofthebed.Backwashingtakesplacecontinuouslyatarelativelylowrate.Thefilterremainscontinuouslyinservice.Nitrogenreleasecyclesarenotrequired.Amoredetaileddiscussionofeachtypeoffilterisprovidedinalatersection.要去除固体物SS，有许多成熟的过滤技术可供污水处理厂进行选择。对于同时具有去除SS和反硝化脱氮功能的过滤池，主要有两大选择：传统的降流式过滤池和升流式连续反冲洗过滤池。就一般意义的过滤而言，有数家厂商可以提供上述两种过滤池。然而，其中只有少数几家开发了同时具有三级反硝化功能的过滤池，本文将对此进行介绍。降流式反硝化滤池以传统的降流式过滤模式运行，由集水系统、支撑卵石和砂组成，配置反冲洗及空气扰动设备，此外还要求有驱氮功能以释放积聚在滤料间的氮气气泡。单格滤池规律性间歇运行以进行短时间反冲洗。升流式连续反冲洗滤池以向上流模式运行。沙床缓慢下降进入空气气提系统，砂子被气提扰动并将被带到沙层顶部。反冲洗以相对较低的速度持续进行。滤池连续运行，无氮气释放要求。本文稍后将对这两种过滤池进行更详细的介绍。LiteratureReview文献综述Deep-beddenitrificationfiltersareawell-proventechnologyformeetinglowtotalnitrogenlimits.Concurrentdenitrificationandsolidsremovalinadeep-bedfilterwasfirstpatentedin1973,andthenfollowedbyaseriesofpatentsforothercomponentsincludingtheuseofbackwashwatertoreleasenitrogengas.DravoCorporation,thenTetraProcessTechnologies,pioneeredthedevelopmentofdenitrificationfiltertechnologyandcontinuedtomakeadvances.Gasremovalfromdeep-bedfiltersthroughventingwaspatentedin1976(USPatentNo.3,970,555),andthedownflowdenitrificationfilterprocesspatentwasupdatedin1979(USPatentNo.4,159,945).Beginninginthelate1970swiththeGainesvilleRegionalUtilitiesKanapahaWWTP(Chen,1980)andtheHowardCurrenAWTPinT