Advanced Test Reactor

ATR vs Commercial Reactor

• Confinement Structure• Operating Conditions– 390 psi– 140 degrees F

• Reactor Core– 4 feet x 4 feet– 880 pounds– 21 pounds of uranium

• Containment Structure• Operating Conditions– 2600 psi– 550 degrees F

• Reactor Core– 12 feet x 15 feet– 154 tons– 12,000 pounds of uranium

Commercial Reactor

ATR

ATR Timeline

Start ofOperations

(6 loops 1967)

2nd Core InternalsChangeout (CIC)

1977

9th Loop Facility Installed, Improved Loop Capabilities 1980

Lead ExperimentFacility Installed

1984

Reactor ControlRoom Replaced

1989

3rd Core InternalChangeout (CIC)

1986

Process Control RoomReplaced & Core Reconfigured

1993

Loop Control SystemReplaced & 4th Core Internal

Changeout (CIC)Decreased Active Loops to 5

1994 External Secondary Piping& Cooling Tower Replacement

1998

Irradiation TestVehicle (ITV) Installed

1999

5th Core InternalChangeout (CIC)

20046th Core Internal

Changeout (CIC) 2010

1967 1987 1997 2007

1st Core Internals Changeout (CIC) 1972

1977

Increased number of loops

from 6 to 8 1973

Plant Protective System Upgrade

2006

ATR Specifications

• Reactor Type

– Pressurized, light-water moderated and cooled, beryllium reflector

• Reactor Vessel

– 3.65 m diameter cylinder, 10.67 m high

– Stainless steel

• Reactor Core

– 1.22 m (diameter & height)

– 40 fuel elements, high enriched U-235

ATR Specifications (continued)

• Coolant Inlet Temperature & Pressure

– 52°C, 2450 kPa

• Thermal Power & Flux

– Maximum Total Core Power – 250MW

– Approximate Peak Flux Values (Unperturbed)

• 1 x 1015 n/cm2–sec thermal

• 5 x 1014 n/cm2-sec fast

ATR Specifications (continued)

• Hafnium Reactivity Control Drums/Rods

– Maintains Axial Flux Shape During Operating Cycle

– Flux/Power Adjustments Among Core Lobes/Flux Traps

• Irradiation Facilities 77

– Reflector Positions 68

– Flux Traps 4

– In-pile Tubes 5

b

Outer Shim Control Cylinder

“B” Position

Fuel Element

Neck Shim Rod(1-6 Typical)

MICE

Inboard “A” Position(1-8)

Outboard “A” Position(9-16)

Standard Loop Irradiation Facility

“I” Position

Outer South Irradiation Tank

South and East Flux Trap

Irradiation Facilities

Safety Rod

“H” Position

Large Loop Irradiation Facility

ITV

Outer North Irradiation Tank

H9

H1

H5H13

H8

H7

H6

H11

H10

H12

H15

H14

H16 H2

H3

H4

31

2

45

17 23

6

M-1

M-3M-2

M-3

ATR Core Cross Section

ATR Vessel & Internals

Irradiation Test Vehicle

ATR Standard Loop Layout

Ion Exchange

Columns

Operating Console

Pumps

PressurizerLine Heaters

Reactor Core

Loop Closure Plugs

Loop Inlet and Outlet Piping

Heat Exchanger