Plans for a new large scale corium facility at

CEA Cadarache: the FOURNAISE project

C. Journeau, J.M. Ruggieri, P. PilusoCEA, DEN, Cadarache (FR)

ERMSAR 2012, Cologne March 21 – 23, 2012

Outline

• Need for prototypic material tests

• FOURNAISE for SFRs

• FOURNAISE objectives

• FOURNAISE general characteristics

• Time schedule

Uranium oxide: specificity and propertiesUranium oxide: specificity and properties

Uranium and some « simulant » element-oxygen systems

U-O system Zr-O system Hf-O system

Many solid compounds with uranium: UO2.00, UO2+x, U4O9, U3O8

Many gaseous compounds with uranium: UO3,UO2,UO,U

Prototypic /simulant material Prototypic /simulant material FCI experiment FCI experiment

corium alumina

-No spontaneous steam explosion with 80%UO220%ZrO2 corium (0.1MPa, sub-cooled water) in KROTOS facility

-Same conditions: very energetic steam explosion with alumina

Specific melt break-up behaviour with prototypic corium:Different configurations of the pre-mixing (and thus explosion)

for alumina and for corium

Operating international prototypic corium experimental facilities(1/2)

PLINIUSFOURNAISE

SICOPS

COMETA

RASPLAV

RASPLAV

ACE/MACELAVA-B

TROIVESTA

SOFI

Operating international prototypic corium experimental facilities (2/2)

• For SFRs> SOFI: few kg SOdium Fuel Interaction test (IGCAR, India)

• For LWRs :> CCI (ANL, USA) : upto 1 t corium (no steel) MCCI > TROI (KAERI, Korea): 20-kg Fuel-Coolant Interaction Test> VESTA (KAERI, Korea) new built 100-kg MCCI facility (oxidic melt)> LAVA-B (NNC, Kazakhstan) : 60-kg scale corium facility. Currently working on

Lower Head corium pools. > RASPLAV (NITI, Russia): 5-20-kg scale facilities: phase diagrams, corium-metal,

aerosols> SICOPS (AREVA, Germany): 5-20 kg MCCI tests> COMETA (UJV, Czech Republic) : kg-scale tests on corium thermochemistry and

aerosol generation> CODEX (EK, Hungary): bundle melting and corium formation> VULCANO (CEA, Cadarache) 25-80 kg facilmity for spreading, MCCI, solidification,

coolability> KROTOS (CEA, Cadarache) 5 kg corium-water interaction> COLIMA (CEA, Cadarache) 2 kg crucible: aerosol generation, material interaction> VITI (CEA, Cadarache) 1-10-g small scale facility: thermophysical properties,

material interactions

ASTRID SFR Severe Accident programme

• CEA is developing the ASTRID Sodium Fast Reactor (SFR) demonstrator for which ambitious goals in term of safety and operability have been set.

> its safety level concerning severe accidents must be at least equivalent to that of the EPR.

• To reach this objective a SFR severe accident project has been launched including a large experimental program with prototypic corium.

• The FOURNAISE facility (Furnace for Oxides of Uranium aimed at simulating Nuclear severe Accidents In large Scale Experiments) is under study at CEA Cadarache to extend the current PLINIUS prototypical platform in order to study the issues linked to SFR severe accidents, with large masses of prototypic corium, especially :

> Fuel Coolant Interaction (FCI)

> corium-material interactions in the core catcher

Based on FARO facility at JRC Ispra

• 2 SFR FCI tests before 1990.

• TERMOS test section> Thermal protection by alumina to enable

tests with Na with low undersaturation (800-900°C)

> Program halted before hi temperature tests due to backfitting for LWR programme.

• 10s of LWR FCI tests.

• 2 spreading tests.

• Direct Electrical Heating furnace

• 110 and 140 kg UO2 poured into Na

• FARA has been dismantled and is in waste storage casks.

LWR Experimental Needs

• Since the Fukushima accident], the interest for large mass experiments for Light Water Reactors (LWR) has grown

• It has been proposed to design the FOURNAISE facility so that it can be applied to severe accident phenomena in both types of reactors.

• For LWRs (Reactor case ~100 t corium)> FCI (steady state requires M > 100 kg)

- Steam explosion- Jet fragmentation and debris formation

> MCCI and ex-vessel coolability- Crust anchorage issues- Surface/Volume ratio

> Optimization/Qualificatiopn of mitigation devices- Core catchers,….

FOURNAISE• A versatile large scale prototypic corium facility made of

> A furnace able to melt large masses of corium - SFR composition: UO2, Steel, core catcher materials…- LWR composition: UO2, ZrO2, Steel, concrete and core catcher materials- Mass in the 100-300 kg range.

> Transfer devices> Test sections dedicated to various objectives

- Corium-sodium interaction- Corium-water inetraction- Corium-material interactions (concrete/ sacrificial material/ refractories)- Coolability issues- Melt Spreading, Debris Levelling- New applications to be determined….

For regulatory reasons, test sections with sodium must be in separate room from test sections with water,

> Material preparation rooms (load, post-test)> Sodium and steam treatment installations

First sketch of facility

Melting technology

• Still under study> Thermitic reactions

- For LWR: Zr+CrO3 + Fe2O3+ (U3O8)….- For SFR: U+CrO3+Fe2O3 + …

> Induction heating - Cold crucible seems the best option to prevent pollution by crucible

material

• Two implementation options are consideredOne furnace + inclined transfer tubes to 2 rooms (sodium/water)Two furnaces sharing the same power supply and services.

• Induction heating will also be available to simulate decay heat in long term experiments.

> Applied largely to oxidic phase.

Tentative time schedule

• Preliminary studies 2012

• Detailed studies 2013

• Construction 2014-2016

• Commissionning and First tests 2016-2017

Conclusions

• The FOURNAISE facility, initially planned for the SFR Severe Accident program, is now being considered as a scientific experimental platform that would be useful to both LWRs and SFRs.

• Its general lay-out would be close to that of the FARO facility, > but it will take account of all the technological knowledge gained on

corium experimentation in the last 20 years.

• It should be available around 2017 for experimental research programs for both Sodium Fast Reactors and Light Water Reactors on :

> Fuel-Coolant Interaction, corium coolability,

> Corium-Material Interaction (material being concrete, sacrificial ceramic,…).

• When available, this new prototypic corium facility will be an asset for the European Research Area on Severe Accidents.

> Complementary to current European corium facilities.