ModuleModule 0404 WWER/WWER/ VVERVVER ((SovietSoviet designeddesigned PressurizedPressurized WaterWater ReactorsReactors))
Prof.Dr. H. Böck Vienna University of Technology /Austria Atominstitute Stadionallee 2, 1020 Vienna, Austria [email protected] VVER=VVER= VedaVeda--VodyanoiVodyanoi EnergeticheskyEnergetichesky Reaktor=Reaktor= WaterWater CooledCooled PowerPower ReactorReactor
WWERWWER 440/230440/230 WWERWWER 440/213440/213 WWERWWER 1000/3201000/320 CommonCommon FeaturesFeatures ofof VVERsVVERs (1)(1)
•• HexagonalHexagonal fuelfuel assemblyassembly cassettescassettes •• HorizontalHorizontal steamsteam generatorgenerator •• PrimaryPrimary circuitcircuit andand secondarysecondary circuitcircuit usingusing differentdifferent materialsmaterials •• ReducedReduced inspectioninspection possibilitiespossibilities ofof componentscomponents •• LittleLittle documentationdocumentation (440/230)(440/230) CommonCommon FeaturesFeatures ofof VVERsVVERs (2)(2) mainlymainly validvalid forfor 440/230440/230
•• LackLack ofof indepententindepentent controlcontrol andand regulatoryregulatory supervisionsupervision •• QualityQuality lacklack inin instrumentationinstrumentation,, controlcontrol andand datadata processingprocessing •• NotNot reproducablereproducable safetysafety analysisanalysis •• LowLow powerpower densitydensity duedue toto highhigh ratioratio ofof waterwater volumevolume toto thermalthermal powerpower CommonCommon FeaturesFeatures ofof VVERsVVERs (3)(3) TechnicalTechnical AspectsAspects ofof VVERsVVERs forfor 1st1st GenerationGeneration •• VVERsVVERs areare thethe „„workhorsesworkhorses““ ofof formerformer SovietunionSovietunion •• Simple,Simple, cheapcheap andand robustrobust contructionscontructions •• RelyRely moremore onon overdimensionoverdimension thanthan onon sophisticatedsophisticated computercomputer codescodes •• LittleLittle automatisationautomatisation,, humanhuman reliabilityreliability isis higherhigher thanthan thethe reliabiltyreliabilty ofof I&CI&C systemssystems •• AccidentAccident preventedprevented withwith choicechoice ofof materialmaterial andand materialmaterial dimensiondimension DevelopmentDevelopment ofof VVERsVVERs VVERVVER FuelFuel AssemblyAssembly VVERVVER FuelFuel PelletsPellets VVERVVER RefuellingRefuelling NewNew FuelFuel VVERVVER PrimaryPrimary CircuitCircuit VVERVVER SteamSteam GeneratorGenerator
Structure of the steam generators in VVER-440 units 1 - steam generator body, 2 - primary cold leg collector, 3 - primary hot leg collector, 4 - manhole, 5 - heat exchanger tubes, 6 - vertical distance grid, 7- horizontal distance grid, 8 - feedwater pipeline, 9 - separator, 10 - perforated sheet, 11 - steam header, 12 - primary circuit header cover, 13 - secondary circuit header cover, 14 cover seals for the primary and secondary circuit, 15 - secondary circuit seal cover monitoring location, 16 secondary circuit air vent, 17 - primary circuit seal cover monitoring location, 18 - primary circuit air vent, 9 - header periodic blowdown, 20 - steam generator periodic blowdown, 21 - steam generator permanent blowdown, 22 - nozzle, 23 - pipe unions for steam generator level checking. VVERVVER GenerationsGenerations WWERWWER 440/230440/230 VVERVVER 440440 // 230230 SafetySafety AspectsAspects •• Six primary loops •• Motor driven valves in all six loops •• Fuel follower control rods •• Two NPP on one site •• Common turbine generator hall for both NPPs •• Rooms designed to withstand higher pressure instead of full pressure containment •• No full capacity emergency core cooling system in case of main coolant pipe rupture •• Accelerated material embrittlement due to fast neutron irradiation of pressure vessel VVERVVER 440/213440/213
Legend: 1.Reactor pressure vessel, 2.Steam generator, 3.Refueling machine, 4.Spent fuel pit, 5.Confinement system, 6.Make-up feedwater system, 7.Protective cover, 8.Confinement system, 9.Sparging system, 10.Check vales, 11.Intake air unit, 12.Turbine, 13.Condenser, 14.Turbine block, 15. Feedwater tank with degasifier, 16. Preheater, 17.Turbine hall crane, 18.Electrical instrumentation and control compartments. VVERVVER 440/213440/213 SafetySafety AspectsAspects
•• Many safety deficits of VVER 440/230 removed •• Pressure suppression system through bubble condensor •• Emergency core cooling system designed for maximum LOCA •• Safety systems in 3 x 100% redundancy, separated from operational I&C system •• Improved fire protection •• Separated emergency control room •• Reduction of neutron fluence to pressure vessel wall •• Surveillance system of safety relevant primary components
VVERVVER 1000/3201000/320 SafetySafety AspectsAspects •• FullFull pressurepressure containmentcontainment designeddesigned 0.50.5 MPaMPa •• EmergencyEmergency coolingcooling systemsystem designeddesigned forfor wholewhole spectrumspectrum ofof LOCALOCA •• ImprovedImproved materialsmaterials forfor primaryprimary andand secondarysecondary componentscomponents •• ImprovedImproved accessaccess forfor reinspectionreinspection andand maintenancemaintenance •• LowLow leakageleakage corecore loadingloading toto reducereduce neutronneutron fluencefluence toto pressurepressure vesselvessel wallwall •• ForFor TemelinTemelin onlyonly:: •• ReplacementReplacement ofof totaltotal II && CC systemsystem,, byby WestinghouseWestinghouse •• FuelFuel elementselements producedproduced byby WestinghouseWestinghouse NPPNPP TemelinTemelin
•• CzechCzech RepublicRepublic •• VVERVVER 1000/3201000/320 •• 22 ReactorsReactors •• 22 xx 981981 MWeMWe NPPNPP MochowceMochowce
•• SlovakSlovak RepublicRepublic •• VVERVVER 440/213440/213 •• 22 ReactorsReactors •• 22 xx 440440 MWeMWe NPPNPP DukovanyDukovany
•• CzechCzech RepublicRepublic •• VVERVVER 440/213440/213 •• 44 ReactorsReactors •• 44 xx 440440 MWeMWe ReferencesReferences
• http://www.nti.org/db/nisprofs/russia/reac tor/power/novovoro.htm • http://www.npp.hu/index-e.htm • http://www.nrc.gov/