PRESSURIZED WATER REACTORS Prof Dr Haluk UTKU Institute

PRESSURIZED WATER REACTORS Prof. Dr. Haluk UTKU Institute of Nuclear Sciences Hacettepe University Ankara, Turkey

GENERAL SYSTEM March 27 -28 th, 2008, WORLD CONJUNCTURE IN NUCLEAR TECHNOLOGY: Generation III and III+ Nuclear Power Plants, Istanbul

REACTOR VESSEL 27 -28 Mart 2008, NÜKLEER TEKNOLOJİDE DÜNYA KONJONKTÜRÜ: III. Ve III+ Nesil Nükleer Reaktörler Kongresi, İstanbul Picture: Mıtsubishi Heavy Industries

REACTOR VESSEL Control Rod Drive Mechanism Vessel Head Rod Cluster Control Mechanism Coolant Inlet Nozzle Core Barrel Neutron Reflector Control Rod Thimble Guide Height (m) 11. 5 -13. 5 Thickness (mm) 180 -255 Internal Diameter (m) 3. 4 -5. 2 Weight (ton) 240 -590 Max. Pressure (Atm. ) 170 Max. Temperature (o. C) 343 Material Manganese Molibdenium Steel (Linen: Stainless Steel, 3. 2 mm) Coolant Outlet Vessel Fuel March 27 -28 th, 2008, WORLD CONJUNCTURE IN NUCLEAR TECHNOLOGY: Generation III and III+ Nuclear Power Plants, Istanbul

REACTOR CORE DIMENSIONS MWe 600 900 1200 1500 Power (MWth) 1650 2652 3411 4451 Core Equivalent Diameter (m) 2. 5 3. 0 3. 4 3. 9 Core Active Height (m) 3. 7 Total Fuel Assembly 121 157 193 257 27 -28 Mart 2008, NÜKLEER TEKNOLOJİDE DÜNYA KONJONKTÜRÜ: III. Ve III+ Nesil Nükleer Reaktörler Kongresi, İstanbul

FUEL Top Coolant Flow Nozzle Fuel Rods Control Rod Guides Instrumentation Guide at the Center Grid Filter Bottom Flow Nozzle March 27 -28 th, 2008, WORLD CONJUNCTURE IN NUCLEAR TECHNOLOGY: Generation III and III+ Nuclear Power Plants, Istanbul Pictures: GE, Mitsubishi Heavy Ind. , Westinghouse

FUEL Total Fuel Assembly* 121 - 257 Assembly Lattice 14 x 14 – 17 x 17 Distance Between Fuel Rods in an Assembly(cm) 0. 31 cm Fuel Rod Diameter (cm) 0. 94 U-235 enrichment (%) 1. 9 – 4. 95 Core Total Fuel Weight (ton) 89 - 121 Burnup (MWd/MTU) 33000 - 60000 * For a reactor with 193 fuel assambly there are 51000 fuel rods and approximately 18 million fuel pelets. 27 -28 Mart 2008, NÜKLEER TEKNOLOJİDE DÜNYA KONJONKTÜRÜ: III. Ve III+ Nesil Nükleer Reaktörler Kongresi, İstanbul

FUEL FAILURE RATES IN US PLANTS

CONTRIBUTION OF FUEL CYCLE TO POWER GENERATION COST Natural Uranium and Processing (%2. 6) Enrichment (%3. 6) %80 %20 Production of Fuel Assembly (%2. 6) Disposal (%11. 2) March 27 -28 th, 2008, WORLD CONJUNCTURE IN NUCLEAR TECHNOLOGY: Generation III and III+ Nuclear Power Plants, Istanbul

REACTOR CORE COOLANT SYSTEM Steam Generator Reactor Coolant Pressure (Atm. ) Secondary System Presssure (Atm. ) ~153 ~ 60 Coolant Flow Rate (m 3/h/loop) 2. 01 x 104 for 3420 MWth 2. 58 x 104 for 4450 MWth Pump Shaft Power (k. W) ΔP (Atm. ) 4470 – 7460 6 Coolant Inlet Temperature (o. C) Coolant Outlet Temperature (o. C) ~ 288 ~ 328 Pressurizer Coolant Pump Ractor Vessel 27 -28 Mart 2008, NÜKLEER TEKNOLOJİDE DÜNYA KONJONKTÜRÜ: III. Ve III+ Nesil Nükleer Reaktörler Kongresi, İstanbul

Coolant Pump - Pressurizer March 27 -28 th, 2008, WORLD CONJUNCTURE IN NUCLEAR TECHNOLOGY: Generation III and III+ Nuclear Power Plants, Istanbul

STEAM GENERATORS • Recirculating Steam Generators: Westinghouse-USA; Mitsubishi Heavy Industries-Japan; Siemens -Kraftwerke-Germany; Babcock & Wilcox-Canada • Once-Through Steam Generator: Babcock & Wilcox, USA • Horizontally Placed Steam Generators: Zio, Atommash-Russian; Vitkovice -Check 27 -28 Mart 2008, NÜKLEER TEKNOLOJİDE DÜNYA KONJONKTÜRÜ: III. Ve III+ Nesil Nükleer Reaktörler Kongresi, İstanbul

RECIRCULATING STEAM GENERATORS Steam Outlet Steam Separators Feedwater Inlet Downcomer Annulus Tube Bundle Tube Supports Tube Sheet Primary Inlet Primary Outlet March 27 -28 th, 2008, WORLD CONJUNCTURE IN NUCLEAR TECHNOLOGY: Generation III and III+ Nuclear Power Plants, Istanbul References: www. kntc. re. kr

ONCE-THROUGH AND HORIZONTAL STEAM GENERATORS Steam Generator To Turbine Perforated plates To Reactor From Reactor coolant flow tubesı Pressure 63 Atm. Feedwater Temp. 220 -225 o. C Moisture at the outlet 0. 2%

CONTAINMENT BUILDING Containment Design relies on calculating the peak containment pressure during potential accidents. The containment must withstand the pressure and temperature of Design Basis Accident without exceeding the design leakage rate of 0. 2% volume/day for the 24 hours and 1% volume/day thereafter. Steel linen is used inside to protect from any gas diffusion. Applied Regulations: 10 CFR 50, Appendix A, General Design Criteria 52, 53 and 54 10 CFR 50, Appendix J 27 -28 Mart 2008, NÜKLEER TEKNOLOJİDE DÜNYA KONJONKTÜRÜ: III. Ve III+ Nesil Nükleer Reaktörler Kongresi, İstanbul

CONTAINMENT BUILDING Sandia National Laboratories, USA conducted a test of slamming a jet fighter into a large concrete block at 775 km/h airplane left a 6. 4 cm deep gouge in the concrete. Although the block was not constructed like a containment building missle shield, the results were considered indicative. In another work EPRI, Electric Power Research Institute, conducted a aircraft crash impact analysis. Analysis showed that no parts of the aircraft entered the containment buildings. The robust containment structure was not breached (Boeing 767 -400, weights 203 tons with full fuel, the wing span is 51. 5 m. ) March 27 -28 th, 2008, WORLD CONJUNCTURE IN NUCLEAR TECHNOLOGY: Generation III and III+ Nuclear Power Plants, Istanbul

ENGINNERING SAFETY FEATURES • • • Decay heat removal system after shutdown Residual heat removal system Emergency core cooling cystem Containment spray system Radiation control systems Systems to filter accumulated gas in the containment 27 -28 Mart 2008, NÜKLEER TEKNOLOJİDE DÜNYA KONJONKTÜRÜ: III. Ve III+ Nesil Nükleer Reaktörler Kongresi, İstanbul

THE REACTIVITY CONTRIBUTIONS OF DEVICES AND PHYSICAL PHENOMENON Relative deviation from the criticalitiy is called reactivity. 1. Shutdown Rods 2. Gray Rods 3. Dark Rods 4. Xenon 5. Fuel Temperature reactivity feedback 6. Moderator (Coolant) Temperature & boron reactivity feedback Note that reactivity is a computed parameter, and not a measured parameter. It is not directly available at an actual plant. March 27 -28 th, 2008, WORLD CONJUNCTURE IN NUCLEAR TECHNOLOGY: Generation III and III+ Nuclear Power Plants, Istanbul