1. LEADER Project Overview
3th LEADER International Workshop
Analysis and design issues of LFR reactor concept: ALFRED
Pisa, 4th -5th September 2012; Bologna, 6th -7th September 2012
Luigi Mansani

2. SUMMARY
Introduction
Nuclear Energy Sustainability
Lead cooled Fast Reactors – Why?
FP7 LEADER Project
Roadmap towards an industrial LFR fleet in Europe
ALFRED (Implementation schedule, design guideline, configuration) and ELFR (configuration)
Some important facts

3. Introduction - Generation IV Goals & Concepts
Sustainability
Safety & Reliability
Economics
Proliferation Resistance & Physical Protection
GENERATION IV SYSTEMS ACRONYM
Sodium-Cooled Fast Reactor System SFR
Gas-Cooled Fast Reactor System GFR
Lead-Cooled Fast Reactor System LFR
Molten Salt Reactor System MSR
Supercritical-Water-Cooled Reactor System SCWR
Very-High-Temperature Reactor System VHTR

4. European framework and context
European energy policy, aiming at fulfilling the “ ” strategy by 2020, relies on a wide implementation of nuclear technologies, including a new Generation of Fast Neutron Reactors oriented to the sustainability of nuclear energy through the actual closure of the fuel cycle
The Strategic Research Agenda (SRA) of the Sustainable Nuclear Energy Technology Platform (SNE-TP) has selected three Fast Neutron Reactor systems (SFR, LFR and GFR) as a key structure in the deployment of sustainable nuclear fission energy
Among the technologies under investigation in Europe Lead-cooled Fast Reactors (LFRs) represent one of the promising solutions, candidate as an alternative to the reference technology, based on Sodium-cooled Fast Reactors (SFRs)

5. ESNII* Roadmap from the Concept Paper
Fast Neutron Reactors in the frame of the European Sustainable Nuclear Industrial Initiative (ESNII)
ESNII* Roadmap from the Concept Paper
(*) ESNII will address the need for demonstration of Gen-IV Fast Neutron Reactor technologies, together with the supporting research infrastructures, fuel facilities and R&D work
All documents are available for download on

6. Sustainability: Partitioning and Transmutation (P&T)
The radio-toxicity of the fission products dominates the total radio-toxicity during the first 100 years and reaches the uranium ore mine level at about 300 years
The long-term radio-toxicity is dominated by the actinides (mainly by the Pu and Am isotopes) and the uranium ore mine level is reached only after more than 120,000 years
By recycling and then ‘burning’ all the MA, the period over which high-level radioactive waste remains hazardous could theoretically be reduced from hundreds of thousands of years down to a few hundred years

7. Strategy for Sustainability of Nuclear Energy
Present known resources of Uranium represent about 100 years of consumption with the existing reactor fleet
Fast neutron reactors with closed fuel cycle have the potential:
to multiply by a factor 50 to 100 the energy output from a given amount of uranium (with a full use of U238),
To improve the management of high level radioactive waste through the transmutation of minor actinides
to provide energy for the next thousand years with the already known uranium resources
Both fast spectrum critical reactors and sub-critical ADS are potential candidates for dedicated transmutation systems
Critical reactors, however, loaded with fuel containing large amounts of MAs pose safety problems caused by unfavourable reactivity coefficients and small delayed neutron fraction
Core fuelled with only MA (Uranium free) has no Doppler nor Delayed Neutrons

8. Example of Closed Fuel Cycle in Fast Reactors
Sustainability:
Example of Closed Fuel Cycle in Fast Reactors
Fabrication
LFR
Adiabatic
Reprocessing
All Actinides
(Expected MA: 1% of which 20% Cm)
MOX first loads
(U:82.5%; Pu: 17.5%)
Unat/dep: 1g/MWD
+ reintegration of losses
FP: 1g/MWD
+ losses
MOX equilibrium
(U: 82%; Pu: 17%; MA: 1%)
LFR can be operated as adiabatic:
Waste only FP, feed only Unat/dep
Pu vector slowly evolves cycle by cycle
MA content increases and its composition drift in the time
LFR is fully sustainable and proliferation resistant (since the start up)
Pu and MA are constant in quantities and vectors
Safety - main feedback and kinetic parameters vs MA content

9. Why LEAD? – Some Advantages LEAD COOLANT PASSIVE SAFETY
Lead does not react with water or air
Steam Generators installed inside the Reactor Vessel
Very high boiling point (1745°C ), very low vapor pressure ( °C)
Reduced core voiding reactivity risk
Lead has a higher density than the oxide fuel
No need for core catcher (molten clad and fuel float)
Lead is a low moderating medium and has low absorption cross-section.
No need of compact fuel rods (large p/d defined by T/H)
Very low pressure losses (1 bar for core, 1.5 bar for primary loop)
Very high primary natural circulation capability natural circulation DHR
LEAD COOLANT PASSIVE SAFETY

10. Why LEAD? – Not Only Advantages
High Lead melting point (~ 327 °C) – assure Lead T above °C
Overcooling transient (secondary side) may cause Lead freezing
Corrosion / erosion of structural materials - Slugging of primary coolant
Seismic risk due to large mass of lead
in-service inspection of core support structures
fuel loading/unloading management by remote handling
Steam Generator Tube rupture inside the primary system
Flow blockage and mitigation of core consequences

11. Why LEAD? – Not Only Advantages
PROVISIONS
High Lead melting point (~ 327 °C) – assure Lead T above °C
heating system, design and operating procedures
Overcooling transient (secondary side) may cause Lead freezing
FW requirement – diversification and redundancy – Really a safety issue?
Corrosion / erosion of structural materials - Slugging of primary coolant
Coatings, oxygen control, limit flow velocity (Russian approach)
Strategy at low oxygen content (alternative approach)
Seismic risk due to large mass of lead
2-D seismic isolators, vessel hanged, specific design (EU FP7 SILER project)
in-service inspection of core support structures
Similar to other HLM reactors but high T, all components replaceable
fuel loading/unloading by remote handling
Develop appropriate cooling system (active  passive back-up)
Steam Generator Tube rupture inside the primary system
Show no effect on core, provide cover rupture disks to limit max pressure
Flow blockage and mitigation of core consequences
Hexagonal wrapped FAs – outlet temperature continuous monitoring
Full unprotected flow blockage causes cladding damages to a max of 7 FAs

12. The FP7 LEADER Project
The first step in the development of a Lead Cooled Critical Fast Reactor in Europe started in 2006 with the EU - FP6 ELSY project, on the basis of previous projects already carried out in the frame of projects dedicated to Lead-Bismuth/Lead cooled Accelerator Driven Systems (XT-ADS, EUROTRANS etc.)
On March 2010 a first reference configuration of an industrial size (600 MWe) LFR was available.
On April 2010 the LEADER project started its activities with the main goal to:
Develop an integrated strategy for the LFR development
Improve the ELSY design toward a new optimized conceptual configuration of the industrial size plant, the ELFR conceptual design.
Design a scaled down reactor, the LFR demonstrator – ALFRED, using solutions as much as possible close to the adopted reference conceptual design but considering the essential need to proceed to construction in a short time frame.

13. Conceptual Design for Lead Cooled Fast Reactor Systems
The FP7 LEADER Project
Conceptual Design for Lead Cooled Fast Reactor Systems
16 European Organization are participating to the project
Project Coordinator - Ansaldo Nucleare
3 year Project ( ), started April 2010
LEADER Project Work Packages:
WP1 - SCK CEN : Design Objectives and Specification
WP2 - ENEA : Core design
WP3 - ANSALDO : Conceptual design
WP4 - EA : Instrumentation, control/protection systems
WP5 - KIT-G : Safety and transient analysis
WP6 - KIT-G : Lead Technology
WP7 - KTH : Education and Training

14. Roadmap towards an industrial LFR fleet in Europe
The main drawback facing the industrial deployment of a LFR fleet in Europe is the lack of operational experience
A satisfactory technological readiness
has been achieved in Russia in the past
century driven by military research
To fill the technology gap in Europe requires the setting up of a complete R&D roadmap, in analogy with what has been done in France for the development of the SFR technology chain, whose readiness is almost proven
Nuclear submarine 705 serial
( )

15. Roadmap towards an industrial LFR fleet in Europe
For the demonstration of the LFR technology chains, further facilities (either existing or under construction) are required to provide the overall frame for LFR technology development, like:
all the existing and planned EU lead labs focused on thermal/hydraulics, materials development and corrosion testing;
the zero-power facility Guinevere, already operating in Mol, Belgium,
the irradiation facility and pilot plant MYRRHA, to be built and operated in Mol and,
the European training facility ELECTRA, planned for realization in Sweden
Guinevere
MYRRHA
ELECTRA

16. Roadmap towards an industrial LFR fleet in Europe
The LFR development roadmap towards the industrial deployment of a fleet of European LFRs, requires:
first a Demonstrator reactor (ALFRED) for proving the viability of reliable electricity production for LFR systems – 125 MWe
second a Prototype reactor (PROLFR) is envisaged for testing the scaling laws at an intermediate step according to a common approach focused both on plant size and representativeness of the target reference system – 300÷400 MWe
third a First-Of-A-Kind (ELFR-FOAK) representative of a commercial ELFR fleet – 600 MWe

17. ALFRED - Implementation schedule
The realization of ALFRED will allow:
the European scientific nuclear community to maintain the leading position in fast reactors design, construction and licensing,
the industries to advance in the field of fast reactor components and systems design and manufacturing, preparing to the advent of a new Generation of nuclear systems for the sustainable energy future of Europe
ALFRED is a Fundamental Step in the Development of Lead Fast Reactor
ALFRED Implementation schedule
consortium
Basic Design, Siting and pre-licensing
Detailed design
&
licensing
construction
Conceptual design
(LEADER)

18. ALFRED - Design Guidelines
ALFRED will be connected to the electrical grid
Power close to 125 MWe (300 MWth)
The LFR Demonstrator design should be based as much as possible on available technology to speed up the construction time
Design solution (especially for Safety and Decay Heat Removal function) should be characterized by very robust and reliable choices to smooth as much as possible the licensing process
Decay Heat Removal System based on passive technology to reach the expected high Safety level
DHRs based on Active actuation and Passive operation

19. ALFRED - Reactor Configuration
MAIN COOLANT PUMP
FUEL ASSEMBLIES
Power: 300 MWth
Primary cycle: °C
Secondary cycle: °C
STEAM GENERATOR
MAIN COOLANT PUMP
STEAM GENERATOR
REACTOR CORE
REACTOR VESSEL
SAFETY VESSEL

20. ELFR - Reactor Configuration
Pumps integrated in the SGs
Spiral SGS (8) – once through
Hexagonal Wrapped FAs
FAs extended to cover gas
Core Bottom grid
Inner shroud – lateral restraint
FAs weighted down by Tungsten ballast (pumps off)
FAs kept in position by top springs (pumps on)
4 Isolation condenser connected to SGs (DHR1)
4 Dip coolers immersed in the main vessel (DHR2)
Power: MWth
Primary cycle: °C
Secondary cycle: °C

21. Main Parameters Emergency conditions Parameter ELFR ALFRED
Primary Coolant
Pure Lead
Electrical Power/Efficiency, MWe/%
632 / 42
125 / 41
Primary System
Pool type, Compact
Primary Coolant Circulation:
Normal operation
Emergency conditions
Forced by mechanical pumps
Natural
Core Inlet/outlet Temperature, °C
400 / 480
Fuel Assembly
Hexagonal, wrapped, weighted down by ballast with pumps off, Forced by springs with pumps on
Max Clad Temperature, °C
550
Max. core pressure drop, MPa
0.1 (30 min grace time for ULOF)
1st System for Shutdown/control
Buoyancy Absorbers Rods: control/shutdown system passively inserted from core bottom
2nd System for Shutdown
Pneumatic Inserted Absorber Rods: shutdown system passively inserted from core top
Secondary System Pressure/steam temp, MPa / °C
18 / 450
Steam generators
integrated in the reactor vessel Spiral type
integrated in the reactor vessel Double wall Bayonet tubes
DHR System
2 Passive DHRs (Actively actuated, Passively operated) DHR N°1 based on ISOLATION CONDENSER concept; DHR N°2 based on deep cooler
2 Passive DHRs (Actively actuated, Passively operated) based on ISOLATION CONDENSER concept

22. Last but not least …. some important facts for ALFRED
GUINEVERE is operating
FEED contract for MYRRHA – Offers delivered
Experimental work on-going, spread over EU research Labs
An MOU between Romania/Italy Organizations has been signed in February 2012 to define the steps and rules to be followed to form an international consortium for ALFRED Design and Construction. Intended location of ALFRED is Romania
Romania’s Prime Minister, Mr. Victor Ponta, participating to “Nuclear 2012” hosted by INR in May, has acknowledged the importance of ALFRED and committed, on behalf of his Government, to ask the Commission to host ALFRED in Romania
STRONG SYNERGIES have been identified between SFR and LFR technologies
(HeliMNet meeting – Aix en Provence – October 2011 –

23. GIF LFR Reference Concepts
LFR MOU signed by Japan and Euratom October 2010
LFR MOU signed by Russia July 2011
Presentation to the GIF Symposium in San Diego – November 2012
Development of a position paper on LFR safety
System Research Plan will be revised – expected issue end of 2012
LFR Reference concepts: SSTAR, BREST 300, ELFR
SSTAR ( MWe)
BREST 300 (300 MWe)
ELFR (600 MWe)

24. THANK YOU FOR YOUR ATTENTION