PEACE : a Prototype of the Energy Amplifier for a Clean Environment

Future of ADS Y. Kadi 1

Y. KadiCERN, Switzerland

29 January 2007, Energy Forum, Bergen, Norway

PEACE :a Prototype of the Energy Amplifier for a

Clean Environment


OUTLINE

PEACE: an Industrial Prototype of the EnergyAmplifier for a Clean Environment

Motivations

General Features of Energy Amplifier Systems

Experimental Validation

Implementation Strategy

Time Schedule


A new primary energy source

By 2050, the world’s consumption (+ 2%/y) should reach 34 TW, of which 20 TW should come from new energy sources: A major innovation is needed in order to replace the expected “decay” of the traditional energy sources!

This implies a strong R&D effort, which is the only hope to solve the energy problem on the long term. This R&D should not exclude any direction a priori! Renewables Nuclear (fission and fusion) Use of hydrogen

Can nuclear energy play a major role?

Nuclear energy has the potential to satisfy the demand for a long time (at least 15 centuries for fission, essentially infinite for fusion if it ever works), and is obviously appealing from the point of view of atmospheric emissions.


Which type of nuclear energy?

Nuclear fusion energy: not yet proven to be practical. Conceptual level not reached (magnetic or inertial confinement?). ITER a step, hopefully in the right direction.

Nuclear fission energy: well understood, and the technology exists, with a long (≥ 50 years) experience, however, present scheme has its own problems:

• Military proliferation (production and extraction of plutonium);

• Possibility of accidents (Chernobyl [1986]; Three Mile island [1979]);

• Waste management. However, it is not given by Nature, that the way we use

nuclear fission energy today is the only and best way to do it. One should rather ask the question:Could nuclear fission be exploited in a way that is acceptable to Society?

To answer this question, Carlo Rubbia and his team at CERN have carried out, in the 1990’s, an extensive experimental programme (FEAT, TARC) which has led to a conceptual design of a new type of nuclear fission system, driven by a proton accelerator, with very attractive properties (Pioneering work by Ernest Lawrence, Wilfrid Bennett Lewis, Hiroshi Takahashi, Charles D. Bowman).


Basic Principle of Energy Amplifier Systems

One way to obtain intense neutron sources is to use a hybrid sub-critical reactor-accelerator system called Accelerator-Driven System:

The accelerator bombards a target with high-energy protons which produces a very intense neutron source through the spallation process.

These neutrons can consequently be multiplied (fission and n,xn) in the sub-critical core which surrounds the spallation target.



Subcritical system driven by a proton accelerator:

Fast neutrons (to fission all transuranic elements) Fuel cycle based on thorium (minimisation of nuclear waste) Lead as target to produce neutrons through spallation, as neutron moderator and as heat carrier Deterministic safety with passive safety elements (protection against core melt down and beam window failure)




Energy Amplifiers vs Critical Reactors

Main objective is to reduce the production of nuclear waste (TRU)

Energy Amplifier : sub-critical fast neutrons Thorium + 233U +TRU (Pu + Minor Actinides)

Reactor : critical slow neutrons Uranium + Pu


Physics of Sub-Critical Systems

EAs operate in a non self-sustained chain reaction mode

minimises criticality and power excursions

EAs are operated in a sub-critical mode

stays sub-critical whether accelerator is on or off

extra level of safety against criticality accidents

The accelerator provides a control mechanism for sub-critical systems

more convenient than control rods in critical reactor

safety concerns, neutron

economy

EAs provide a decoupling of the neutron source (spallation source) from the fissile fuel (fission neutrons)

EAs accept fuels that would not be acceptable in critical reactors

Minor Actinides High Pu content LLFF...

EAs operate in a non self-sustained chain reaction mode

minimises criticality and power excursions

EAs are operated in a sub-critical mode

stays sub-critical whether accelerator is on or off

extra level of safety against criticality accidents

The accelerator provides a control mechanism for sub-critical systems

more convenient than control rods in critical reactor

safety concerns, neutron

economy

EAs provide a decoupling of the neutron source (spallation source) from the fissile fuel (fission neutrons)

EAs accept fuels that would not be acceptable in critical reactors

Minor Actinides High Pu content LLFF...


Safety margin from prompt criticality

For a critical system, it is measured by the fraction of delayed neutrons. For the Energy Amplifier, it is an intrinsic property, and can be chosen.

Subcriticality implies strong damping of reaction to reactivity insertion, making the system very stable (presence of higher modes in neutron flux).

Keff < ksource The parameters of the system can be chosenso that k < 1 at all times.


Reactivity Insertions

Figure extracted from C. Rubbia et al., CERN/AT/95-53 9 (ET) showing the effect of a rapid reactivity insertion in the Energy Amplifier for two values of subcriticality (0.98 and 0.96), compared with a Fast Breeder Critical Reactor.

2.5 $ (k/k ~ 6.510–3) of reactivity change corresponds to the sudden extraction of all control rods from the reactor.

There is a spectacular difference between a critical reactor and an EA (reactivity in $ = /; = (k–1)/k) :







Nuclear waste: the priority in developed countries

TRU:(1.1%)produced by neutron capture;dominated by plutonium: destroy them through fission

Fission Fragments:(4%)the results of fissions transform them into stable elements through neutron capture

235U 236U 237U 238U 239U 240U

237Np 238Np 239Np 240Np

238Pu 239Pu 240Pu 241Pu 242Pu 243Pu

241Am

243Am

6.75 d 23.5 mn 14.1 h

2.12 d 2.35 d 61.9 mn(7.2 mn)

14.3 yr 4.96 h

582 15

2100

78 742 1100 200

3

98.3 5.11 440 2.75 22

180 2.75 68

540 269 290 380 18.5 90

242Am

580 74

γγ

γ γ90Br 90Kr 90Rb 90Sr 90Y

143Xe 143Cs 143Ba 143La 143Ce 143Pr

γ β− β−

(neutron)

Fission Fragments

Gamma Radiation

Stable

Stable

235U

γ β− γ β− γ β− γ β−

143Nd

γ β− β−γ β− γ β− γ β−

90Zr

n

n

n

n

0.3 s 1.78 s 14.33 s 14.2 mn 33 h 13.57 d

1.92 s 32.32 s 2.63 mn 28.78 y 64.1 h


Evolution of radiotoxicity of nuclear waste

TRU constitute by far the main waste problem [long lifetime – reactivity]. The system should be optimized to destroy TRU. Same as optimizing for a system that minimises TRU production. Interesting for energy production!

Typically 250kg of TRU and 830 kg of FF per Gwe


Maximizing fission probability

Note: thermal fission resilient element

s

Note: thermal fission resilient element

s

The strategy consists in using the hardest possible neutron flux, so that all actinides can fission instead of accumulating as waste.


Fast neutrons and high burn-up

Fast neutrons allow a more efficient use of the fuel by allowing an extended burnup

Fast neutrons allow a more efficient use of the fuel by allowing an extended burnup







Thorium as fuel in a system breeding 233U

It is the presence of the accelerator which makes it possible to choose the optimum fuel.Low equilibrium concentration of TRU makes the system favourable for their elimination: Pu 10–4 in Th vs 12% in U.


Radiotoxicity

The radiotoxicity of spent fuel reaches the level of coal ashes after only 500 years, and is similar to what is predicted for future hypothetical fusion systems


Why not Thorium Reactors

Thorium is not vigorously fissile => it needs a source of neutrons to kick-off the chain reaction.

Thorium also cannot maintain criticality on its own => it cannot sustain a chain reaction once it has been started (Pa-233)

The question until now has been how to provide thorium fuel with enough neutrons to keep the reaction going and do so in an efficient and economical way.


MOTIVATION for ADS

Accessible, clean & cheap energy for countries requiring more energy to reach normal development.

Nuclear energy without accidents and radioactive waste. (sub-critical & fast neutrons)

Nuclear energy without proliferation risks (Th fuel)


OUTLINE

PEACE: an Industrial Prototype of the EnergyAmplifier for a Clean Environment

Motivations


Experimental Validation

Implementation Strategy

Time Schedule


The FEAT experiment

3.6 tons of natural uranium


The TARC Experiment

ÿ Understanding the phenomenology of spallation neutrons in lead (neutron flux measurements by electronic detectors and by activation measurements, etc.)

ÿ Direct test of Transmutation of Long-Lived Fission Fragments (

99Tc,

129I) by Adiabatic Resonance Crossing

ÿ Development & validation of appropriate simulation/computing tools


Transmutation of Nuclear Waste: Fission Products

Radio-Isotope

Half-Life

(years)

Mass

(kg)

Activity @ 1000 yr

(Ci)

Ingestive Toxicity

(Sv) 103

Dilution Class A

(m3)

129I 1.57 x 107

8.09 1.43 19.58 178.47

99Tc 2.11 x 105

16.61 284.29 27.67 947.65

126Sn 1.0 x 105

1.187 33.79 3.20 9.65

135Cs 2.3 x 106

34.12 39.32 9.87 39.32

93Zr 1.53 x 106

26.11 65.64 2.38 18.75

79Se 6.5 x 105

0.30 2.06 0.745 0.59

Fission Fragments activity and toxicity after 1000 years of cool-down in a Secular Repository

(Values are given for 1 GWe ´ year)


Experimental Setup


TARC Results (2)


R&D Activity in Europe

Vast R&D activity in Europe over last 10 years: 12 countries, 43 institutions

EU 31 MEuros

Member States 100 MEuros

Vast R&D activity in Europe over last 10 years: 12 countries, 43 institutions

EU 31 MEuros

Member States 100 MEuros


In FP5, a complementory combination of test facilities was set up in Europe.

EUROTRANS is

fully using these test facilities.

STELLA LoopCEA

CIRCE LoopENEA

TALL LoopKTH

CIRCO LoopCIEMAT

CorrWett LoopPSI

VICE LoopSCK-CEN

CHEOPE LoopENEA

DEMETRA: Test Facilities


Gelina @ Geel (UE-Belgium)

GSI @ Darmstadt (Germany)

Cyclotron @ Uppsala (Sweden)

nTOF @ CERN (Switzerland)and its TAS γ-calorimeter

Neutron capture (n,γ) resonances in one actinide

NUDATA: Experimental Facilities


F. G

roes

chel

et a

l. (P

SI)

MEGAPIE Project at PSI

0.59 GeV proton beam

1.3 MW beam power Goals: Demonstrate

feasablility One year service

life Operating since

August 2006

Proton Beam

MEGAPIE TARGET


SINQ SPALLATION NEUTRON SOURCE


Open Questions

• The material selection problem for the internal core structures as well as for the spallation target module and fuel cladding in contact with LBE;

• The HLM technology should be answering the problems of LBE conditioning and filtering in pool design conditions;

• The development of the needed instrumentation for LBE quality monitoring in order to guarantee a safe and efficient operation of LBE cooled ADS: O2-Meters, ultrasonic visualisation under LBE, HLM Free surface monitoring, sub-criticality monitoring, LBE velocity field measurement;

• The material selection problem for the internal core structures as well as for the spallation target module and fuel cladding in contact with LBE;

• The HLM technology should be answering the problems of LBE conditioning and filtering in pool design conditions;

• The development of the needed instrumentation for LBE quality monitoring in order to guarantee a safe and efficient operation of LBE cooled ADS: O2-Meters, ultrasonic visualisation under LBE, HLM Free surface monitoring, sub-criticality monitoring, LBE velocity field measurement;


Open Questions

• Key Accelerator components should be demonstrated, namely the reliable working for periods of 3 months of the injector;

• The spallation module based on the windowless concept (most promising of achieving high performance core) should be fully designed from the mechanical and thermal-hydraulic aspects;

• The coupling of the ADS components (accelerator, spallation module and a sub-critical core) should be realised at realistic power that would allow to study the thermal feedback reactivity assessment, the on-line subcriticality monitoring and control at various keff values.

• Key Accelerator components should be demonstrated, namely the reliable working for periods of 3 months of the injector;

• The spallation module based on the windowless concept (most promising of achieving high performance core) should be fully designed from the mechanical and thermal-hydraulic aspects;

• The coupling of the ADS components (accelerator, spallation module and a sub-critical core) should be realised at realistic power that would allow to study the thermal feedback reactivity assessment, the on-line subcriticality monitoring and control at various keff values.


UO2+PuO 2

UO22+

PuO22+

Technology of pyrochemical

reprocessing of fuel

Technologies of fast reactors with lead-bismuth coolantLiquid metal targets

technology

High power accelerators

technology

ROAD MAP FOR PEACE


Accelerator choice

Cyclotron = MODULAR, realised on industrial scaleCost effective ; applicable in isolated regions ;applicable for desalination & cogeneration

Linear accelerator = Solution for Research Centres & highly centralised production


The SVBR-75/100 MWe Reactor Unit

• Integral design with the steam generators sitting in the same Pb-Bi pool at 400-480ºC;

• Russia built 8 Alfa-Class submarines, each powered by a compact 155MWth Pb-Bi cooled reactor, and 80 reactor-yrs operational experience was acquired with these;

• As follow-up of Russian programme of Pb-Bi cooled fast neutron reactors for Alpha type submarines, the multi-purpose reactor module SBVR75 is now available on the “market” (90M$, Stephanov et al. 1998, Gidropress).


Aqueous method (Japan)


Principle Electro-refining in a molten salt solution with electrodes at different potentials

Actinides Separated from Fission Products and high level waste: Plutonium is combined with minor Actinides (Np, Am, Cm) and an approximately equal amount of U

fully tested at the laboratory level

Very efficient (> 99.9%) No effluents waste, all chemicals

recycled: no discharges in the environment

Small size and easy to operate: it may be located on the reactor site or near by, minimising fuel transport

Non proliferating: all TRU’s always intimately mixed

Small batches: no criticality risks.

Pyro-processing


The Prototype of the Energy Amplifier for a Clean Energy

The key objective of PEACE is threefold:

p Demonstrating the technical feasibility of a fast neutron operatedAccelerator Driven System (ADS);

p Lead-Bismuth Eutectic coolant;

p Incineration of TRUs and LLFF while producing energy.


The PEACE : Plant Layout


The modified version of SVBR-75 reactor for PEACE

Steam generator

∅ 3 500


The PEACE : Global Parameters


Plutonium incineration in ThPu based fuel is more efficient and settles to approximately 43 kg/TWh, namely 4 times what is produced by a standard PWR (per unit energy). The minor actinide production is very limited in this case.

Long-Lived Fission products incineration is made possible in a very efficient way through the use of the Adiabatic Resonance Crossing Method. Such a machine could in principle incinerate up to 4 times what is produced by a standard PWR (per unit energy).

The PEACE : Transmutation Rates

Transmutation rates (kg/TWthh) of plutonium and minor actinides and LLFPs

NuclidesEADF

(ThPuO2)ENDF/B-VI

EADF(UPuO2)

ENDF/B-VI

EADF(UPuO2)

JENDL-3.2

PWR(UO2)

233U + 31.0Pu – 42.8 – 7.39 – 5.55 + 11.0Np + 0.03 + 0.25 + 0.24 + 0.57Am + 0.24 + 0.17 + 0.14 + 0.54Cm + 0.007 + 0.017 + 0.020 + 0.044

99Tc prod + 0.99 + 1.07 +1.22 + 0.9999Tc trans – 3.77 – 3.77129I prod + 0.30 + 0.31 + 0.17129I trans – 3.01 – 3.01

Future of ADS Y. Kadi

Phase 1 Phase 2 Phase 3

Proton Driver Power

250 MeV*3 mA= 0.75 MWth

250 MeV*6 mA= 1.5 MWth

900 MeV*6 mA= 5.4 MWth

Gain G0 0.75 0.75 2.5

Sub-criticality level, k

0.95 0.975 0.975

Gain=Go/(1-k) 15 30 100

Thermal Power Output

11.25 MWth 45 MWth 540 MWth


The Generalized Stages for Realizing the PEACE Program

Nos. Essential res earch Work Participants Realization Period

Expenses, k€

1 Preparation of the Program The PEACE Working Group 1st Semester 2 Selection of the experimental

facilities and research lines. Selection of the demonstration facility parameters.

The PEACE Working Group + Collaborating Institutions.

2nd Semester

3 Feasibility Study same 2nd Year 5,000 4 Working design of the

demonstration facility same 3rd Year 45,000

5 Realization of the experimental and simulation program to support the PEACE facility feasibility study

same 1st - 7th

Year 50,000

6 Construction and commissioning of the PEACE facility

The PEACE Working Group + Collaborating Institutions + Industrial Partners

5st - 7th

Year 450,000


Time Schedule


Accelerator CERN (CH), PSI (CH), AIMA (F), IBA (B) Spallation source

Basic spallation data CERN (CH), GSI (D), PSI (CH) Feasibility of the windowless design UCL (B), FZR (D), FZK(D), NRG

(NL), CEA (F) + ENEA (I) + IPUL (Latvia) Subcritical assembly

RSC “Kurchatov Institute”, Moscow – designing target – blanket systems; investigation and justification of the fuel cycle in transmutation systems, including radiochemical problems.

SSC RF IPPE, Obninsk – target – blanket system construction at the SSC RF IPPE site, the functions of designer and production engineer of the element (component) base for the blanket.

OKB “Hydropress”, Podolsk – Chief designer of the target – blanket system.

GSPI and VNIPIET, St. – Petersburg – Design work at the SSC RF IPPE site. SSC RF _ VNIINM, Moscow – MOX fuel development and justification; IYaI RAN, Troitsk – R&D work in justification of subcritical system

physics. NIKIET, Moscow – Chief designer of the equipment for the IYaI RAN site. ENEA (I), CEA (F), BN (B), UoK-UI (LT), TEE (B),CIEMAT (SP)

Fuel US, EUR, INDIA, RUSSIA Safety EUR, RUSSIA Robotics EUR Building EUR

R&D Program Partnership Network


Why such a delay ?

• The option of high level waste transmutation via ADS is not yet fully accepted by all European nuclear countries or at least a majority of them as the most appropriate way of doing it;

• Besides this situation one should mention that in Europe there are many fuel cycle scenarios in application ranging from the once-through scenario up to the double-strata one.

• There are also various policies regarding nuclear energy ranging from the continuous development up to the phase out policy

• The option of high level waste transmutation via ADS is not yet fully accepted by all European nuclear countries or at least a majority of them as the most appropriate way of doing it;

• Besides this situation one should mention that in Europe there are many fuel cycle scenarios in application ranging from the once-through scenario up to the double-strata one.

• There are also various policies regarding nuclear energy ranging from the continuous development up to the phase out policy


VHTR RomneyDuffey

Werner Von Lensa

Frank Carre

Tetsuaki Takeda

Jonghwa Chang

Dieter Matzner

Wolfgang Hoffelner

Tim Abram

Finis Southworth

Didier Haas

Jean-LouisCarbonnier

Tomoyasu

MizunoJonghwa Chang

Johan Slabber

Paul Coddington

Denis Every

Kevan Weaver

SFR Gian-Luigi Fiorini

Masakazu Ichimiya

Shoji Kotake

Dohee Hahn

Tim Abram Tom Lennox

Bob Hill

LFR Luciano Cinotti

Mamoru Konomura

Kune Y. Suh

Craig F. Smith

SCWR HussaKhartabi

Thomas Schulenberg

Marc Delpech

Katsumi Yamada

Yoshiaki Oka

Yoon-Yeung Bae

Mike Modro

MSR Miloslav Hron

Claude Renault

Charles Forsberg

GFR


Conclusions

Can atomic power be green ? Physics suggests it can !!

Present accelerator technology can provide a suitable proton accelerator to drive new types of nuclear systems to destroy nuclear waste (including nuclear weapons) and/or to produce energy.

An Energy Amplifier could destroy TRU through fission at about x4 the rate at which they are produced in LWRs. LLFF such as 129I and 99Tc could be transmuted into stable elements in a parasitic mode, around the EA core, making use of the ARC method.

Next step: PEACE ? when ? where ?

Documents

PEACE : a Prototype of the Energy Amplifier for a Clean Environment