火力发电W火焰炉技术介绍.ppt

Zhenxiong,2x600MWSupercriticalBoilersFiringAnthraciteCoal,DoosanBabcockEnergy,HBC,WfiringCombustiontechnology.低挥发份无烟煤W火焰锅炉技术LowMassFluxFurnaceDesign低质量流速直流锅炉技术3.WFiringandLowMassFluxStudyandApplicationW火焰低质量流速超临界方案DesignConsiderationsforZhenxiong振雄工程方案介绍,Section介绍分为:,ZhenxiongEvaluation,HBC,DownshotWfiringisthemostwidelyusedtechnologyforburninganthracitefuels,Zhenxiong,下冲对冲,RecentExperienceFiringLowVolatileCoals,*,HBC,LowVolatileandAnthraciteBoilers低挥发份无烟煤锅炉,HBC,FurnaceFiringArrangement,HBC,Existing600MWeWFiringSubcriticalBoiler,DB600MWeLaiocheng聊城电厂,Cycloneconcentrators旋风分离器浓缩,Fuel+PA+SAentry燃料一次风二次风入口,TertiaryAirentry三次风入口,HBC,600MWeBoilerComparison,DB600MWeLaiocheng聊城,MaximumEvaporation最大蒸发量2027t/h1900t/hSHSteamPressure主蒸汽压力17.27MPa25.4MPaSH&RHSteamTemperature主汽/再热汽温541/541571/569LowerFurnacedepthxwidth下炉膛深度x宽度21642x2668023666x26680Lowerfurnaceplanarea(m2)下炉膛断面积541.5595.5UpperFurnacedepthxwidth(mm)上炉膛深度x宽度10488x2668012512x26680Upperfurnaceplanarea(m2)上炉膛断面积279.8333.8Furnaceoverallheight炉膛总高度5058756200Furnacevolume炉膛容积1655421114,DB600MWeZhenxiong,HBC,DifficultiesAssociatedWithLowVolatileFuels燃烧低挥发份煤种相关的问题,Ignitionofcoalbecomesmoredifficultasvolatilecontentreduces.挥发份降低将使得煤粉点燃更加困难Lowunburnedcarbonlevelsbecomeincreasinglydifficulttoattainasvolatilecontentreduces,especiallyforVdaf12%.随着挥发份降低尤其是Vdaf降低到12%以下，未燃尽碳损失将增加Flamestabilisationandminimumloadwithoutoilsupportfiring.火焰的稳定性和最低无油稳燃负荷LowNOxlevelsalsobecomemoredifficulttoachieveandthisisrecognisedintherelevantemissionregulations很难达到低NOx排放，这一点在相应的国家排放标准中已体现-lessvolatileN2inthecoal挥发物中含氮量少-highcombustiontemperaturesneededforignitionandburnout煤粉点燃和燃烬需要很高的燃烧温度Thesedifficultiesnecessitate:克服以上问题需要Finepfgrading均匀良好的煤粉细度Longfurnaceresidencetimes煤粉在炉膛内停留时间长Carefulairadmission分级配风Optimisedfurnacerefractorycover优化炉内卫燃带布置,HBC,secondaryairslotsfedfromwindbox二次空气狭槽，来自风箱的进风,primaryair&fuelslotsfedfromcyclone来自自旋风器的高浓度一次风,ventairslotsfedfromcyclone来自放风器的乏气风,cyclonetoseparateairandfuel旋风器分离空气和燃料,TypicalBurnerArrangement典型的燃烧器布置,fuelfrommilloutlet来自磨机出口的燃料,airintoWindbox空气进入风箱,HBC,BurnerandVentAirSlotDistribution燃烧器和乏气风分布,HBC,DoosanBabcockSlotBurners狭缝式燃烧器,Coal煤,lowvelocityprimaryairrapidheating&ignition低流速一次风迅速加热和点火highvelocitysecondaryairforlongflamedevelopment高流速二次空气用于长火焰的扩展noswirl无涡流gradualmixing逐步混合flamepenetration火焰贯穿longparticleresidencetime煤粉颗粒停留时间长,Combustionair燃烧空气,Coal煤,HBC,DoosanBabcockDownshotCombustionSystem,Directfiring-modern,reliable&safe直吹式燃烧系统现代化的、可靠的和安全的Doubleendedtubemillsdelivering95%148.000,243.000,uniform,uniform,oneside,oneside,ParameterRangeforInvestigationsonRifledTubes内罗纹管的试验参数变化范围,Pressuresteps:25,50,70,100,150,175,200,210,212.5,215,217.5,220,230,250,280bar,0,100,200,300,400,500,600,700,800,900,0,200,400,600,800,1000,1200,1400,1600,Massflux(kg/ms),Heatflux(kW/m)(relatedtotubeinside),RR1,RR2,RR4,RR5,RR7,RR8,RR9/RR12/RR16,RR18/RR19,RR20,Tube:,Equivalent,Insidediameter:,13-35mm,Zhenxiong75%lowerfurnace,*,*,Zhenxiong100%lowerfurnace,HeatTransferExperimentsperformedonRifledTubes内罗纹管传热试验,Heatflux(kW/m),Massflux(kg/ms),0,100,200,300,400,500,600,700,800,900,1000,0,100,200,300,400,500,600,700,800,Boilingcrisisx0.9x0.9)传热良好的区域,HeatTransfer传热,Heattransfer,particularlynearcriticalpressure应特别注意在临界压力附近的传热Inaverticaltubingdesignwithrifledtubesitistheheattransferonlynearthecriticalpressurethatmustbeensured,whereasinaspiraldesignwithsmoothtubestheheattransferintheentireloadrangemustbechecked.在垂直内螺纹管圈设计中,临界压力附近的传热必须得到保证,而螺旋光管设计中,整个负荷变化区域的传热需要进行校核TheheattransferbehaviorofrifledtubeswasinvestigatedintheBensontestrigforallexpectedgeometriesandoperationalconditions.对于内螺纹管的传热特性,通过在本生试验台对不同几何尺寸的管子和在不同运行负荷下进行试验,得到第一手的数据Theworldbiggestdatabaseofheattransferandpressuredropmeasurementsguaranteesasafeandeconomicdesign.世界上最大的传热和压降试验数据库为安全和经济设计提供保证,HBC,Yaomeng-VerticalTubeLowMassfluxOnceThroughBoiler姚孟低质量流速垂直管圈直流锅炉,世界上唯一的一台已投运低质量流速直流锅炉.英巴是唯一拥有这方面经验的锅炉厂,HBC,姚孟工程的设计特点及设计难度,姚孟电厂是国内300MW亚临界直流锅炉，原设计炉膛断面偏小，造成炉膛截面热负荷高，水冷壁热负荷高，水冷壁工作条件恶劣。姚孟电厂原设计炉膛为双炉膛，中间水冷壁为双面受热，工作条件更改恶劣，同时受到结构的限制不能在水冷壁中间设置中间过渡集箱或压力平衡集箱等平衡压力的设施。与本工程相比姚孟工程改造的水冷壁系统设计难度更大，英国斗山巴布科克公司根据其多年的电站锅炉的设计经验，利用低质量流速垂直管圈水冷壁技术成功对其进行改造，改造后的锅炉完全能够适应定-滑-定的运行方式。对姚孟工程的成功改造充分验证了低质量流速垂直管圈水循环技术的可行性。,OptimizedRifledTubes优化内罗纹管,ReduceWallTemperatures降低金属壁温or或AllowsReductionofMassFluxes降低质量流速,OutletTemperatureDifferences出口温度偏差,ConsiderationResponseResult,Evaporatoroutlettemperaturedifferences水冷壁出口温度偏差Incontrasttoaspiraldesigntemperaturedifferencesintheverticallowmassfluxdesignareinthesamerangeatallloads.与螺旋管圈相比,低质量流速垂直管圈在各个负荷范围内的温差变化是在相同的范围内Verticaldesignislesssensitivetodifferingoperationalconditions.随着运行工况变化垂直管圈设计的出口温差敏感性较小,HBC,DensityofWaterasFunctionofPressureandTemperature密度与压力和温度的关系,HBC,LowVolatileSupercriticalSolution低挥发份无烟煤超临界锅炉方案,ThegeometryofaWfiredboilermakestheadoptionofaspiralfurnaceverydifficultW火焰锅炉若采用螺旋管圈方案，布置将非常困难ThesolutionincorporatestheDoosanBabcockLowMassFluxtechnologypioneeredatYaomeng.方案结合了英巴率先在姚孟项目上成功应用的低质量流速技术,HBC,OctagonalLowerFurnacePlan下炉膛为八角形断面chamferedcornersensurethatallfurnacetubesareexposedtosimilarheatfluxdistributionevenwithextensiverefractorycoverage切角设计已保证炉膛所有管子所受到均匀的热负荷,VerticalTubeOnceThroughDownshotFurnace超临界垂直管圈炉膛设计,HBC,WFiredVerticalTubeFurnaceW火焰垂直管炉膛,OnceThroughSupercriticalBoiler直流超临界锅炉Bensonboilerfeaturing(本生锅炉特性)Verticaltubefurnaceconstruction垂直管炉膛结构Maximumoutput最大出力672MWeSuperheateroutletpressure25.4MPa过热器出口压力Superheateroutlettemperature571过热器出口温度Reheatoutletsteamtemperature569再热器出口温度,HBC,BoilerOperatingEnvelope锅炉运行范围,Slidingpressureoffersadvantages:HighpartloadefficiencyRapidstart-up/ShutdownandloadchangingLowerpressurepartstressatpartloadleadingtoextendedlife.滑压运行的好处：锅炉在部分负荷运行时效率高快速启动/停炉和负荷变化在部分负荷运行时受压部件处于低应力状态从而可以延长寿命,Allboilerheatingsurfaces(includingfurnace)operateunderslidingpressure.锅炉所有受热面可以滑压状态下运行,HBC,Inadoptingtothisapproach,therewereseveralmajorissueswhichhadtobesolvedbeforethefeasibilityofaWfiredLMFboilercouldberealised采用W火焰垂直管圈方案需要解决的主要问题Furnacetubediameter水冷壁管径TubediameterssmallerthanequivalentNCdesign.Reducedloadbearingcapacityresults.Detaileddesigncheckscarriedoutwiththefollowingsolutionsidentified由于其管径比自然循环汽包炉要小，相应的负荷承载能力会降低。结合采用以下方案，已经完成详细设计校核Minimisednumberofbenttubes(non-loadcarrying)减少“弯管”的数量（非承重管)Increasednumberoffurnacefrontandrearwallslingtubes/rods增加前墙和后墙的悬吊管/吊杆的数量UseofmorespringloadsupportsandsolidslingscomparedwithNCdesign与自然循环汽包炉相比采用更多的支承和实心吊杆,LowVolatileSupercriticalSolution低挥发份无烟煤超临界锅炉方案,HBC,ContFluidSideCircuitry流体侧回路ThelowerfurnaceslingtubesusedforNCboilerarenotsuitableforOTSCsituationbecausethelargethermaldifferentialbetweenthefurnacetubesandtheslingtubesandalsobecausetheriskofflowstagnationintheunheatedslingtubes.ThesolutionhasbeenBifurcationsinthenoseandfrontandrearwallslingsupporttubeshavebeeneliminated取消折焰角处的分叉管Solidslingrodsforloadsupportshavebeenusedinstead采用实心吊杆支承,LowVolatileSupercriticalSolution低挥发份无烟煤超临界锅炉方案,HBC,LowVolatileSupercriticalSolution低挥发份无烟煤超临界锅炉方案,Numberofbenttubesenteringfurnacetopheadersminimised减少进入炉膛上部集箱的弯管,SubcriticalDrumTypeBoiler亚临界W火焰锅炉,SupercriticalLMFTypeBoiler超临界低质量流速W火焰锅炉,SolidSlingRods实心吊杆,HBC,ContFurnaceTubeMetalTemperatures炉膛金属壁温Foroncethroughfurnace,thefluidtemperaturesofdifferenttubesarevariedandheattransfercrisisarenotavoidable.对于直流锅炉，过大的水冷壁管子偏差和传热恶化是不允许的。Toprovidesafeandreliableoperationofaonce-throughboiler,itiscriticaltoensuretheminimisedpeaktubemetaltemperatureswithreliabletubecoolingandlimitedtemperaturedifferentialbetweenadjacentevaporatortubes.我了保证直流锅炉能够安全可靠的运行，必须保证在任何情况下水冷壁内的工质对水冷壁管子有足够高的冷却能力，同时避免出现过大的偏差来降低水冷壁管子的壁温Calculationsshowthatbothtemperaturedifferentialsandpeakmetaltemperatureshavebeenminimisedbyadoptinglowmassfluxandoptimisedribbedtubesselectedforthisproject.计算显示采用优化型内螺纹管的低质量流速垂直管圈技术可以解决上述问题，满足锅炉安全运行的要求。,LowVolatileSupercriticalSolution低挥发份无烟煤超临界锅炉方案,HBC,FLUENTFlowPatternCase275%GHR,CFD(Fluent)ModellingUsedtoDetermineFlowPaths建立计算机流动场模型来确定流动场,Modelscreatedforeachloadwithdifferingburnergroupsfiring对应不同的负荷，不同燃烧器组投运的方式建立计算机流动场模拟模型75%isclosetocriticalpressure75%负荷对应的压力接近临界压力Frontwallpenetratinglowerfurnacedeeperasallburnergroupsfiring由于不同燃烧器组投运的原因,可以看到前墙的流场沿下炉膛方向下冲地更深,HBC,DoosanBabcockprogramusedtodetermineheatdistribution,WFiringBoilers,HBC,Detailedheatfluxdistributioniscalculatedforeachloadandforeachsectionoffurnacewall,WFiringBoilers,HBC,Heatfluxusedtodeterminetubemetaltemperatures热通量决定管子的金属壁温,100%Frontwall100%负荷前墙,HBC,Heatfluxusedtodeterminetubemetaltemperatures热通量决定管子的金属壁温,75%Frontwall75%负荷前墙,HBC,ContStaticandDynamicstability静态和动态稳定性Staticstabilityinvestigateshowthepressuredropoveratube(orgroup)reactstoincreasingflowwithconstantheatinput.Foratwophasefluid,dependantongeometry,pointofheatinput,amountofsteamgenerated,whereitoccursandtheresultantpressurelosscouldleadtoinstabilities静态稳定性研究的是在输入热量恒定的情况下,管子或管组的压降随流量增加而产生的变化。对于两相流,取决于其几何尺寸,输入热量的位置,产汽量,蒸发点,其合成的压降可能会导致不稳定性发生。Dynamicstabilityinvestigateshowatube(orgroup)reactstoheatinputdisturbance.Theheatinputisupsetbytypicallyastepincreaseinheatinputof20%for10seconds.Theoscillatoryresponseisdeterminedandforawelldesignedsystemtheseshoulddisappearwithin300seconds动态稳定性研究的是在输入热量变化时管子(或管组)相应的变化。输入热量若按恶劣的条件如在10秒中输入热量增加20%考虑。对于良好的一个设计而言振荡波动将可在300秒中内消失Thedesignhasbeencheckedandbothstaticanddynamicresponsesfoundtobesatisfactory静态和动态稳定性均已完成校核而且结果令人满意,LowVolatileSupercriticalSolution低挥发份无烟煤超临界锅炉方案,HBC,DetailedCheckingOfAllAspectsOfFurnaceThermo/HydraulicBehaviourIsImportant炉膛水动力特性的全面详细校核非常重要,ForExample,StaticStabiltyofAllFurnaceTubeCircuits比如，炉膛各个回路的静态稳定性计算,HBC,DynamicStabilityCalculatedandVerified经计算和验证的动态稳定性,GoodresponseInducedupsetsdissipatewithin300secondlimitation,HBC,Overallfurnaceresponsetoincreasesinheatinputexhibitaverygoodpositivecharacteristic下炉膛在各种负荷下具有非常良好的正流量相应特性,PositiveFlowCharacteristicChecked,HBC,ZhenxiongEvaluation,HBC,ZHENXIONGGENERALARRANGEMENT,HBC,ZHENXIONGBoilergeneraldescription,超临界压力变压本生直流炉带循环泵式启动系统型布置平衡通风单炉膛燃用无烟煤采用狭缝式燃烧器火焰燃烧方式采用优化内螺纹管的低质量流速垂直管圈水冷壁主汽温度控制煤水比+2级喷水再热温度控制烟气挡板调温,HBC,ZHENXIONGcoalanalyse,HBC,ZHENXIONGparameter,HBC,ZhenxiongProjectConsiderations,ThefirstconsiderationisthealtitudeoftheZhenxiongsite:Thefurnacehasbeensizedforhighsitealtitude炉膛尺寸的设计已经考虑到高海拔的因素,HBC,FurnaceDimension,下炉膛断面：26.68x23.666m上炉膛断面：26.68x12.512m下炉膛高度：11.494m（冷灰斗拐点到下炉膛出口）上炉膛高度：12.537m（下炉膛出口到屏底）,炉膛断面积（下炉膛/上炉膛）M2595.5/333.8炉膛容积m319658炉膛容积放热强度Kw/m378.16炉膛断面放热强度MW/m22.580燃烧器区壁面放热强度（下炉膛）kW/m2570.9炉膛有效投影辐射受热面放热强度kW/m2159.8炉膛出口烟气温度1020,HBC,FurnaceTubeSelectionZhenxiong,ZhenxiongFurnace,HBC,Corrosionconsiderations（waterwallcoveredwithalloy),secondaryCombustionHightemp.zoneCoveredwithalloy二次燃烧高温区喷涂合金材料,HBC,ZhenxiongFuelConsiderations,Itisimportanttocorrectlyidentifyandspecifytheactualfuelsthatwillbeusedinpractice.Zhenxiongfueldataindicates:应采用实际燃用的煤种作为设计煤种。我们有如下的建议：Highsulphurcontent高硫分(potentialoffurnacecorrosionneedstobeconsidered潜在的炉内腐蚀风险)DoosanBabcockairsupplysystemtothefurnace(wallair,slotburnersforgoodmixing,etc)alreadyprovidesadegreeofprotectiontothewalls英巴的炉膛供风系统(贴壁风，狭缝燃烧器可保证良好混合，等等)已经对炉膛水冷壁提供了一定程度的保护Hightemp.zonecoveredwithalloy在水冷壁高温区喷涂合金材料HighErosionIndex高磨损指数(suitablefluegasvelocitiesofheatingsurfaceswillbeconsideredaswellastheeffectofsitealtitude受热面设计采用低烟气流速并考虑海拔高度的修正)Slagging结焦Lowfurnacerating,lowFEGT,minimumrefractoryusagewillbeadopted将采用低炉膛热负荷，低炉膛出口烟气温度，以及小面积的卫燃带,HBC,TubeMaterialsSelection,CandidateMaterials,Someoperationalquestions.,HR3C&TP347Hneededwherecorrosionresistanceisacriteria.,HBC,Corrosionconsiderations,TheBritishbituminouscoalminedinYorkshiretypicallycontains24%sulphurand0.250.6%chlorine.DoosanBabcockhavesignificantexperiencedesigningboilerswithsteamtemperaturesof568DegCforthesecoals.斗山巴布科克公司设计过硫含量在2-4%，氯含量在0.25-0.6%的英国烟煤的亚临界锅炉（蒸汽参数为568C)Corrosionratecalculationmethodshavebeendevelopedtocalculatecorrosionbasedonfuelanalysis,tubeposition,tubesurfacetemperatureandgastemperature.根据燃料分析、管子布置位置、管子金属壁温及烟气温度来计算烟气侧的腐蚀。Morerecently,aircooledcorrosionprobescomprisinganumberofausteniticalloyspecimenswereinsertedinattwopositionsforaround10,000hoursandtheseresultshavebeenanalysed.斗山巴布科克工资在RactcliffeUnit1机组上对不同材料的抗烟气腐蚀能力作了专门的试验(用空气冷却的金属腐蚀试样，在两个位置作了大约10000小时的试验）TheSuper304andTP347Hshowalinearincreaseincorrosionwithmetalsurfacetemperatureaboveathresholdvalueof550C.TheHR3Cmaterialshowslittleornodependenceonmetaltemperature.试验表明超级304H和TP347H材料在550C以上时其，抗烟气腐蚀的能力随着温度的升高呈线性变化，而HR3C材料则基本不变。Leadingtubesinanarrayaresubjecttomuchhighercorrosionratesthantrailingtubes.试验表明，第一排管子比内部的管子的腐蚀要严重Gastemperatureshaveasignificantimpactoncorrosionrates.烟气温度对腐蚀也有较大的影响CorrosionresistanceoftheTP347HisbetterthantheSuper304.CorrosionrateoftheHR3Cisextremelylow.Corrosionrateincreasesrapidlywhencoalsulphurlevelsincreasefrom1%to2%.Beyond4%sulphur,therateofincreaseflattensoff.试验表明，TP347H材料的抗腐蚀能力好于超级304H材料，HR3C材料的抗腐蚀能力非常优秀，当煤中的硫含量从1%-2%时，腐蚀迅速增加，当超过4%时，腐蚀增加的速度又降下来。Zhenxiongfuelsareverycorrosivewithsulphurcontentsaround2.3%3%.TheTP347HisusedforallthehightemperatureheatingsurfacesexceptthattheHR3Cisusedforsomeleadingtubesandthetubeswithparticularlyhighmetaltemperaturesorgastemperatures.,HBC,SpecificProjectConsiderations,TubeMillsizingisofmajorimportancetoensureproperfunctioningandperformanceofcombustion:钢球磨的出力是保证燃烧性能的主要影响因素Fineness煤粉细度6%retainedat90micronsisessentialforhighefficiency.Themillselectedshouldhavesufficientcapacitytoachievethisfineness.采用R90=6%的煤粉细度是保证锅炉高效率的关键Moisture水分Lowmoisturespecified.Highmoistureisconsideredinequipmentdesignforrainyseason.煤质参数水分较低。设计时应考虑雨季时的高水分。Fluegastemperaturestoairheaterandassociatedprimaryairtemperatureswillbesuitableforfullrangeofcoalmoistures.预热器入口温度以及相应的一次风温度能够适应整个原煤水分的变化范围。Margin裕量Afullrangeofcoalsneedstobeconsideredparticularlyifthefuelsuppliedispotentiallychangeable.设计时要考虑整个煤种的变化范围，。,HBC,SpecificProjectConsiderations,Optimisationofthecombustionsystemrequiresgoodcontrolofcombustionair.Thisisespeciallyimportantfortheselowvolatilefuels:燃烧系统的优化要求能对燃烧配风进行良好控制。这一点对低挥发分煤种尤为重要：SpecialcareandattentionneedstobeappliedtothedesignandlayoutofthePrimaryAirsystem.在一次风系统的设计及布置时要特别考虑这一要求。Adequatestraightductlengthsbeforeandafterairflowmeasuringdevices(venturi/aerofoil)toensureaccurateandreliablereadings.风量测量装置（文丘里或机翼）前后都要有足够的直管段以保证测量的准确性及可靠性。Carefuldesignofthehotprimaryair/temperingairjunctiontoensuregoodmixing,(minimisingstratificationandturbulence)andavoiddisruptingthedonstreamairflowmeasurement.设计热风和调温风的汇合点时要保证两股气流的充分混合，（减少气流分层及涡流）并避免干扰下游的测风装置。,HBC,Summary小结,DoosanBabcockistheonlyboilersupplierwithaprovenworkingexampleofaverticaltubelowmassfluxdesign(Yaomeng).Thecombiningtwoproventechnologies两种成熟技术的结合-DownshotWfiring,and下冲式W火焰燃烧和-VerticaltubeLowMassFluxFurnaces低质量流速垂直管圈hasenabledDoosanBabcocktomakeamajorstepforwardintheefficientutilisationofAnthracitefuels.使得巴布科克在有效利用无烟煤燃料方面向前跨出了一大步。TheDoosanBabcocktechnologyhasgainedtheofficialChineseapproval.巴布科克这一技术已经通过了中国官方组织的技术评审。MajorInterestintheadoptionofthistechnologyfornewbuildboilerapplicationshasalreadybeenexpressedbyanumberofdevelopers,andthefirstprojectZhenxiongiseagerly