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MYRRHAA Multipurpose European ADS for R&D

State-of-the-art at mid.2003

International Workshop on New Applications of Nuclear Fission (NANUF03)

Bucharest (RO), September 7-12, 2003

Hamid Aït AbderrahimOn behalf of the MYRRHA Team

SCKCENBoeretang 200, B-2400 Mol, BELGIUM

myrrha@sckcen.be

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Contents

1. Introduction2. Applications 3. Accelerator4. Spallation target module5. Sub-critical reactor engineering6. Remote handling & ISIR7. Conclusions

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Introduction (2)

MYRRHA is intended to be: A full step ADS demo facility A P&T testing facility A flexible irradiation testing facility in replacement

of the SCKCEN MTR BR2 (100 MW) A fast spectrum testing facility in Europe, beyond

2010 complementary to RJH (F) A testing facility for fusion program An attractive tool for education and training of

young scientists and engineers A medical radioisotope production facility

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R&D Applications (1)

• ADS full concept demonstration coupling of the 3 components at reasonable power level

(ca 40 MWth), operation feed-back, reactivity effects mitigation scalable to an industrial demonstrator

• Safety studies for ADS beam trips mitigation sub-criticality monitoring and control restart procedures after short or long stops feedback to various reactivity injection spallation products monitoring and control …

• MA transmutation studies need for high fast flux level (Φ>0.75MeV = 1015 n/cm².s)

• LLFPs transmutation studies Need for high thermal flux level (Φth > 1015 n/cm².s)

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R&D Applications (2)

• Radioisotopes for medical applications Need for high thermal flux level (Φth = 2 to 3.1015

n/cm².s)

• Material research for PWR and BWR Need for large irradiation volumes with high constant

fast flux level (Φ>1 MeV = 1 ~ 5.1014 n/cm².s)

• Material research for Fusion Need for large irradiation volumes with high constant

fast flux level (Φfast = 1 ~ 5.1014 n/cm².s with a ratio appm He/dpa(Fe) = ~15 )

• Fuel research Need irradiation rigs with adaptable flux spectrum and

level (Φtot = 1014 to 1015 n/cm².s)

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Accelerator1) NC Cyclotron

• Initial choice “Normal Conducting Cyclotron” was motivated by: start from existing technology the most powerful CW accelerator in the

world is the PSI cyclotron : 590 MeV * 1.8 mA

IBA technology : Cyclone-80 (80 MeV but tested up to 7 mA) and cyclotron of proton therapy (250 MeV but limited to few µA)

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Accelerator2) NC Cyclotron solution

• 4 sector cyclotron• physical magnet diameter of 16 m diameter• total weight ~ 5000 t

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Accelerator3) LINAC

• Now considering : Supra-conducting magnets cyclotron for reducing

the dimensions (factor 2) Even better for the ADS demonstration a LINAC

approach is now favoured as a result of the WP3 of FP5 PDS-XADS project, indeed

The LINAC, with SCRF (super-conducting radio-frequency) cavities for the high energy part is considered as "the solution of choice" for high-power accelerator applications, that is for a power level which exceeds, say, 2 MW

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Accelerator4) LINAC

• WP3 is presently investigating in more detail that : such a LINAC matches perfectly the required energy

regime, its inherent modularity allows an easy upgrade to

whatever energy finally demanded for industrial transmutation,

the projected beam currents of such a LINAC, very safely fulfil the industrial request,

• two other considerations emerge as being in particular support for a SCRF based LINAC for ADS: reliability, availability, maintainability cost-optimisation of the operation

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Accelerator5) LINAC sketch for ADS

The PROTON The PROTON linac linac driver driver

? ? ? ? ? ? ? ?

5 MeV 100 keV 10 MeV

RFQ RFQ Source Source

DTL DTL

500 MeV 100 MeV 200 MeV

= 0.65 = 0.5 = 0.85

DTL, SC DTL, SC cavities cavities …? …?

LOW ENERGY LOW ENERGY

section section

INTERMEDIATE INTERMEDIATE

section section

HIGH ENERGY HIGH ENERGY

section section

Injector Injector SCRF SCRF cavities cavities

* 1-2GeV possible

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Spallation Target:1) Radial Geometrical Constraints

Small assembly configuration

p 6

Small assembly reference coreconfiguration

MOX-20% fuel ass.

MOX-30% fuel ass.

Spallation target

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Spallation Target: 2) Boundary Conditions

• 350 MeV, 5 mA proton beam for fast neutron fluxes for transmutation, i.e. 1.75 MW of which 80 % is heat

• 130 mm penetration depth for 350 MeV - Bragg peak

• 72 mm ID radial extent of the beam tube + 122 mm OD radial extent of the feeder - limited by neutronics

• Windowless target due to high beam load - despite vacuum

• Pb-Bi because of neutronic and thermal properties

1.4 MW heat in ~ 0.5 l to be removed while meeting thermal and vacuum requirements

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Spallation Target: 3) Desired Target Configuration

Volume-minimized recirculation zone gets lower ‘tailored’ heat input

Example of radial tailoring

0%

100%

-3,5 -2,5 -1,5 -0,5 0,5 1,5 2,5 3,5

r (cm)

High-speed flow (2.5 m/s) permits effective heat removalIrradiationsamples

Fast coreBEAM

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Spallation Target:4) Design and R&D Approach

Interaction between:• Experiments with increasing complexity and

correspondence to the real situation (H2O–Hg–PbBi)

• CFD simulations to predict experimental results optimize nozzles for experiments simulate heat deposition which can not yet be

simulated experimentally

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DG16.5 Hg Experiments

nominal volume flow 10 l/s60

16.5°

Close to desired configuration ! intermediate lowering of level some spitting axial asymmetry

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DG16.5 H2O Experiments

nominal volume flow 10 l/s

vacuum pressure 22 mbar

Similarity check: OK !

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Spallation Target:5. Future Steps

• Pb-Bi Experiments at FZK (KALLA)

Similar size as IPUL loop Similar complexity as

MYRRHA loop: 2 free surface + mechanical impeller pump

fall 2003

• Pb-Bi Experiments at ENEA (CHEOPE)

Minimum closed loop configuration

MHD pump Speed feedback

regulation test fall 2003

•Proton beam heating Simulation with CFD code (e.g. FLOW-3D)

Simulated or measured flow field

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Spallation Loop Technical Lay-Out

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Sub-Critical Reactor2) Pb-Bi: benefits and drawbacks

Undergoes spallation Reasonable melting temperature (123 °C)Water can be used for the secondary coolingHigh coolant density (steel and fuel float)Opaque: blind fuel handlingPossible problems in case of variation of the

eutectic composition (deposits of high melting point phases)

Bi activates into PoThe compatibility of Pb-Bi with structural and

cladding materials is to be addressed by design

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Sub-Critical Reactor 3) Engineering

• Pool type vessel of 4 m X 7 m height• Standing vessel to alleviate the highest T in case of LOHS

at the most stressed line of the hanging vessel• Low high flux exposure => no risk of irrad. embrittlement• Internal interim fuel storage (2 full cores, no coupling)

• 4 HX groups (2 HX + 1 PP) => total capacity ~80 MW

• Tin = ~200°C, Tout = 350°C, secondary fluid = water

• Spallation loop interlinking with the core, cooled via LM/LM HX with the cold Pb-Bi of the core as secondary fluid

• Fuel handling from beneath via rotating plug

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MYRRHA Core

p 6

Small assembly reference coreconfiguration

MOX-20% fuel ass.

MOX-30% fuel ass.

Spallation target

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Radial Layout

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Vertical View

Proton beam line

Spallation loop

Target nozzleFast core

Main containment vessel

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Remote Handling & ISIR

• Due to the high activation on the top of the sub-critical reactor due to the neutron leakage through the beam-line,

• Due to the a Po contamination when extracting components from the reactor pool,

• Due to non-visibility under Pb-Bi,• We decided from the very beginning to

consider the operation and maintenance of MYRRHA with remote handling systems and develop appropriate ISIR and visualisation systems

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Task Requirements

• Removal and replacement of plant items• Plant maintenance (e.g Spallation zone

replacement)• Decontamination of plant items• Packaging of waste items• Recovery from failure during plant

handling (e.g jamming)• Recovery of a failed Ex-vessel Fuel

Transfer machine• Recovery of debris from Pb-Bi

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7. PLANT LAYOUT AND INFRASTRUCTURE

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MYRRHA RH in action

• Removal of the spallation loop from the reactor and its positioning in the maintenance pit

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MYRRHA Visualisation in action

• Deployment of the In Vessel Inspection Manipulator (IVIM) to inspect the MYRRHA Core internals

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MYRRHA ISIR system in action

• Deployment of the In Vessel Recovery Manipulator (IVRM) : to recover a miss-placed fuel assembly

To inspect the spallation loop circuit ducts

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Conclusions

• MYRRHA design is progressing continuously towards the detailed engineering design

• MYRRHA is developing many innovative feature that can be deployed in any future nuclear facility

• MYRRHA is allowing to maintain high skills in the nuclear field

• MYRRHA is intended to serve the European ADS programme

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Conclusions

• The best merits of ADS and P&T are: the rejuvenation of our field of activity and

you can see that through the amount of requests for PhDs or trainings from young people in this field,

The renewal of bringing fundamental and applied Physics community together,

The revisiting of reactor physics theory and experimental reactor tools