A breeder reactor produces more fuel than it consumes through the conversion of uranium-238 into plutonium-239. Superphenix was a French liquid-metal fast breeder reactor that operated from 1985 to 1998. It had a thermal output of 3000 MW and an electrical output of 1174 MW. It used liquid sodium as a coolant and fuel made of MOX containing 15% uranium and 85% plutonium. Despite advantages like efficient use of uranium resources, breeder reactors also have disadvantages such as producing weapons-grade plutonium and high construction costs.

1. 11/11/2015
LMFBR -
Superphenix
[Liquid-Metal, Fast-Breeder Reactor]
with technical data
Hossam Ahmed Zein
CONTROL ENGINEER – CEPC, EGYPT

2. 1
What is the breeder reactor?
Nuclear reactors are devices that utilize the heat generated during the splitting of
atoms, to produce energy which is used in the generation of power. These
reactors are nuclear reactors which produce more fuel than they utilize in their
operation. They contain an inner core of the plutonium isotope Pu-239 ,
effectively producing the fuel itself.
The remaining neutrons bombard other plutonium atoms, starting a chain
reaction which produces more energy and neutrons. When all the surrounding
uranium is converted to plutonium, the fuel is completely regenerated. A
breeding reactor is named so because it 'breeds' its own fuel.
How it’s done? Ex [Liquid-Metal, Fast-Breeder Reactor]
Called: plutonium-239 breeder reactor
Coolant;
There is a coolant surrounding the reactor which is used to protect the core from
overheating. It absorbs the heat generated during the fission of plutonium atoms and
circulates it to a heat exchanger.
The cooling and heat transfer is done by a liquid metal
This heat converts water in the exchanger into steam, which is used to drive a turbine and
generate electricity
Note: The metals which can accomplish this are sodium and lithium, with sodium being
the most abundant and most commonly used
Fuel;
The construction of the fast breeder requires a higher enrichment of U-235 than a
light-water reactor, typically 15 to 30%.
The reactor fuel is surrounded by a "blanket" of non-fissionable U-238.

3. 2
Moderator; No moderator is used in the breeder reactor since fast neutrons are more
efficient in transmuting U-238 to Pu-239
At this concentration of U-235, the cross-section for fission with fast neutrons is sufficient to
sustain the chain-reaction. Using water as coolant would slow down the neutrons, but the
use of liquid sodium avoids that moderation and provides a very efficient heat transfer
medium.
Let us have a look at the pros and cons of breeder reactors.
Advantages
 A breeder reactor creates 30% more fuel than it consumes. After an initial
introduction of enriched uranium, the reactor only needs infrequent
addition of stable uranium, which is then converted into the fuel.
 It can generate much more energy than traditional coal power plants. Even
3 g of uranium, on undergoing fission, can release ten times the energy
produced by a ton of coal.
 Breeder reactors can even use the uranium waste from uranium processing
plants and spent fuel from traditional fission reactors, along with depleted
uranium from nuclear weapons.
 Uranium-235 used by light-water reactors is rare on Earth, and its reserves
are likely to run out within 100 years. On the other side, uranium-238 used
by breeder reactors is plentiful; in fact as common as tin. In the US alone, its
reserves are expected to last for at least 1,000 years.
 Since it reuses fuel, the expenses for mining, milling, and processing of
uranium ore are minimized.
 Fuel prices of breeder reactors will remain fairly stable because of the
abundance of uranium-238 on Earth.
 This technology does not contribute to air pollution, except during the
mining and processing of uranium ore.

4. 3
 Breeder reactors can use a small core, which is important to sustain chain
reactions. Besides, they do not even need moderators for slowing down
neutrons, as they use fast neutrons.
Disadvantages
 Breeder reactors use highly enriched fuels, which pose the danger of critical
accidents. They also work at a very high temperature and a fast pace.
 The byproducts formed during the fission of plutonium have to be removed
by reprocessing, as they slow down the neutrons and reduce efficiency.
However, this step of reprocessing produces a very pure strain of
plutonium, which is ideal for use in nuclear weapons. This poses a risk, as in,
terrorists may attempt to sabotage or steal the plutonium.
 Plutonium persists for a long time in the environment, with a half-life of
24,000 years, and is highly toxic, causing lung cancer even if a small amount
is inhaled.
 Till date, not a single breeder reactor has been economically feasible. Every
year, billions of dollars worldwide are spent for the safe storage of the
plutonium produced, which is then useless, as few reactors use it as fuel.
 In practice, a breeder reactor requires 30 years to produce as much
plutonium as it utilizes in its operation.
 It requires liquified sodium or potassium metal as a coolant, as water would
slow down the neutrons. These metals can cause a mishap, as they react
violently when exposed to water or air.
 The construction and operation is very costly. Between $4 to $8 billion is
required in the construction alone.
 These reactors are complex to operate. Moreover, even minor malfunctions
can cause prolonged shutdowns. Their repair is tedious and expensive too.
 Breeder reactors have had several accidents. For example, in the US, the
Experimental Breeder Reactor I suffered a meltdown in 1955. Similarly,

5. 4
Reactor Fermi I suffered a partial meltdown in 1966, and was closed down
after a series of sodium explosions. Currently, only Russia, China, India, and
Japan have operational breeder reactors.
Technical Data
France/Superphenix in Creys-Malville
• Criticality: 9/1985
• Shut down: 12/1998
• 1174 MW electrical net
• 3000 MW thermal
• Efficiency: 41.3%
• Fuel assemblies:
– Number of fuel assemblies: 364
– Total length: 5.4 m
– Active length: 1.95 m
– Number of rods per assembly: 271
– Outer diameter fuel rod: 8.5 mm
– Fuel: MOX 15%UO2, 85%PuO2
– Maximum burn up: ca. 100 000 MWd/ton
– Cladding: Stainless steel

6. 5
• Breeding assemblies:
– Number of fuel assemblies: 233
– Total length: 5.4 m
– Active length: 1.95 m
– Number of rods per assembly: 91
– Outer diameter fuel rod: 10.5 mm
– Material: Depleted U-238
– Cladding: Stainless steel
Superphenix Shut Down Systems
 Primary shut down system:  Secondary shut down system:
– Number of control rods: 21 – Number of absorber segments: 3
– Number of absorber fingers per
control rod: 31
– Number of absorber segments per
control element: 3
– Absorber material: Stainless steel – Absorber material: Boron carbide
– Absorber length: 1.3 m

7. 6
Superphenix Coolant Circuits
1 core 6 Turbine
2 control rode 7 Generator
3 IHX intermediate (Na/Na) heat exchangers 8 pump
4 roof slab 9 condenser
5 main reactor vessel 10 river water

8. 7
Superphenix Heat Transfer System
Heat Transfer Assemblies
• Number of primary sodium pumps: 4
• Number of intermediate (Na/Na) heat exchangers (IHX): 8
• Number of secondary sodium pumps: 8
• Number of steam generators: 4
• Number of feed water pumps: 4
• Primary (Na) Coolant Circuit: • Secondary (Na) Coolant Circuit:
– Total amount: 3250 tons – Total amount: 1500 t
– Core inlet temperature: 395 ˚C – Steam Generator (SG) inlet
temperature: 542 ˚C
– Core outlet temperature: 545 ˚C – IHX inlet: 345 ˚C
– Inlet intermediate heat exchanger
(IHX): 542 ˚C
– SG outlet temperature: 345 ˚C

9. 8
– IHX outlet: 542 ˚C
• Water – Steam Circuit:
– SG inlet: 237 ˚C
– SG outlet: 487 ˚C
Reactor Tank Internals

10. 9
Reactor Core
193 fuel assemblies zone 1 3 neutron guides
171 fuel assemblies zone 2 197 steel assembles
21 main control rods 1070 lateral neutron shielding
assemblies
3 backup control rods 6 anti anti-parasite positioners
for zone 1 assemblies
283 blanket aeemblies 6 anti-parasite positioners for
zone 2 assemblies

11. 10
Founadtions

12. 11
Fuel Assembly
• Overall length: 5.4 m
• Active length: 1.95 m
• Total number of
assemblies in core:354
• Number of rods per
assembly: 271
• Cladding material: SST
• Maximum cladding
temperature: 620 °C

13. 12
Refueling Procedure
Refrences
 Schneider FBR France
 Super-Phenix: Ashes To Ashes ; Walt Patterson
 Atominstitute of the Austrian Universities ; Prof.Dr. H. Böck
 • http://www.schneller-brueter.de/index2.htm
 • http://www.ippe.obninsk.ru/rnpp/rnpp_eng.html
 • http://www-frdb.iaea.org/index.html