Werking van moderne kerncentrales

Transcriptie

1 Werking van moderne kerncentrales 1 Uranium U-238 Electronen Atoomkern met protonen (p) en neutronen (n) U-238 U p en 146 n 92 p en 143 n Niet splijtbaar Goed splijtbaar 2 99,3% voorkomen 0,7% voorkomen 1

2 Uraniumverrijking 3 neutron U-235 Moderator U-238 U-235 U-239 Moderator Industriedag U-238 Borssele Pu-239 June 1, Pu-239 Np-239 2

3 Energie dichtheid: equivalent van 1 gram 2500 liter 3000 kg 5 Componenten in reactorkern 6 3

4 Werking van een drukwaterreactor (PWR) 7 Veiligheid van lichtwaterreactoren (LWR) U-235 Moderator Moderator feedback Doppler feedback U-238 U-235 1) stabiel systeem (zelfregeling) U-239 2) verlies van koelcapaciteit schakelt de reactor af Industriedag Borssele June 1, ) verlies van moderatie schakelt de reactor af Np-239 4

5 Nawarmte: verval splijtingsproducten KCB: straalkachels Vervalvermogen [MW/MW] Vervalenergie [MWd] Tijd / dagen koeling blijft noodzakelijk na afschakeling 9 Nawarmte: verval splijtingsproducten Geproduceerde warmte na 0.5 dag bedraagt: MWd 400 MWs = 400 fps Omschrijving C o Splijtstof van 100 naar bedrijfstemp 9 o o Koelmiddel van 100 C naar 286 C 112 ( ) Energie fps Reactorvat en constructiematerialen

6 Principe van meerdere barrieres Splijtstof (tablet en bekleding) Primair systeem (staal) Veiligheidsomhulling (2x beton + staal) 11 Splijtstofelement van een PWR 12 6

7 Belangrijke componenten in een PWR 13 Reactorvat PWR 12 m 4 m 14 7

8 Drukhouder PWR 15 Stoomgenerator PWR 20 m 16 8

9 Vervanging stoomgenerator 17 In bedrijf zijnde commerciële vermogensreactoren in 2000 (bron: Nuclear Engineering International Handbook 2000) Totaal vermogen: 364 GWe 57,9% Drukwaterreactor (PWR) 21,4% Kokendwaterreactor (BWR) 7,8% Gasgekoelde grafietreactor (GCR) 7,6% Zwaarwaterreactor (PHWR) 3,2% Lichtwatergekoelde grafietreactor (LWGR) 0,9% Snelle kweekreactor (FNR) 1,2% Andere reactoren 18 9

10 Werking van een BWR 19 Splijtstofelement BWR 20 10

11 Generaties kernreactoren Generation I Early Prototype Reactors - Shippingport - Dresden, Fermi I - Magnox Generation II Commercial Power Reactors - LWR-PWR, BWR - CANDU - VVER/RBMK Generation III Advanced LWRs - ABWR - System AP600 - EPR Generation III+ Evolutionary Designs Offering Improved Economics AP1000 SBWR PBMR HTRPM Generation IV - Highly Economical - Enhanced Safety - Minimal Waste - Proliferation Resistant Gen I Gen II Gen III Gen IV 21 Defense in depth 1. Design to prevent the occurrence of events (transients) that can result in damage to the fuel or reactor system Negative feedback coefficients Large safety margins Reliable components and well-known materials 2. Protective systems to halt transients Reactor SCRAM systems Pressure relief valves 3. Mitigation systems to limit the consequences of transients Emergency core cooling Emergency secondary feed water systems Emergency electrical Industriedag systems Borssele Multiple barriers to the biosphere June 1,

12 Defense in depth generation II 1. Design to prevent the occurrence of events (transients) that can result in damage to the fuel or reactor system Negative feedback coefficients Large safety margins Reliable components and well-known materials 2. Protective systems to halt transients Reactor SCRAM systems Pressure relief valves 3. Mitigation systems to limit the consequences of transients Emergency core cooling Emergency secondary feed water systems Emergency electrical Industriedag systems Borssele Multiple barriers to the biosphere June 1, Defense in depth generation III 1. Design to prevent the occurrence of events (transients) that can result in damage to the fuel or reactor system Negative feedback coefficients Large safety margins Reliable components and well-known materials 2. Protective systems to halt transients Reactor SCRAM systems Pressure relief valves 3. Mitigation systems to limit the consequences of transients Emergency core cooling Emergency secondary feed water systems Emergency electrical Industriedag systems Borssele Multiple barriers to the biosphere June 1,

13 Defense in depth generation III+ 1. Design to prevent the occurrence of events (transients) that can result in damage to the fuel or reactor system Negative feedback coefficients Large safety margins Reliable components and well-known materials 2. Protective systems to halt transients Reactor SCRAM systems Pressure relief valves 3. Mitigation systems to limit the consequences of transients Emergency core cooling Emergency secondary feed water systems Emergency electrical Industriedag systems Borssele Multiple barriers to the biosphere June 1, European Pressurized-water Reactor reactorgebouw turbinegebouw Industriedag Borssele 4 veiligheidsgebouwen 4 x 100% June 1,

14 Dubbele veiligheidsomhulling beton staal beton bestand tegen de inslag van een groot verkeersvliegtuig 27 Passief gekoelde Core catcher koelwater 28 14

15 Advanced Passive PWR 1117 MWe (Westinghouse VS) 29 Passieve veiligheidssystemen: minder componenten 30 15

16 Passieve noodkoeling van veiligheidsomhulling 31 Generaties BWR gen II gen III gen III+ ABWR ESBWR 32 16

17 High Temperature Reactor (HTR) 33 TRISO splijtstof 34 17

18 Pebble-Bed Modular Reactor 35 Overzicht van moderne kerncentrales Generatie III Generatie III + ABWR EPR AP1000 ESBWR PBMR HTR-PM Type BWR PWR PWR BWR HTR HTR Generatie III III III + III + III + III + Vermogen VS certificatie ja 2007 ja 2010 nee nee In gebruik In aanbouw Respijtperiode 72 uur 30 min. 72 uur 24 uur Kernsmeltfrequentie (1/jaar) core catcher nee ja <24 uur <24 uur onnodig onnodig Constructietijd (jr) ? Technische levensduur (jr) ?? 36 18