Baldev Raj Baldev Raj Distinguished Scientist Distinguished - - PowerPoint PPT Presentation

Baldev Raj Baldev Raj

Distinguished Scientist Distinguished Scientist & & Director Director Indira Gandhi Centre for Atomic Research Indira Gandhi Centre for Atomic Research Kalpakkam Kalpakkam

Materials Development and Related Issues Materials Development and Related Issues in Closed Nuclear Fuel Cycle with in Closed Nuclear Fuel Cycle with Fast Breeder Reactors Fast Breeder Reactors

Electricity Generation

(GWe) 122.3

Nuclear Energy Share

(GWe) 3.31

PHWR (GWe)

2.99

Faster Growth needed to reach the target FBR with Closed Fuel Cycle & High Breeding Ratio inevitable

2005 2052

~ 1344 ~ 275 ~ 0

5305 3699 2454 1620 1000 613 1000 2000 3000 4000 5000 6000 2002 2012 2022 2032 2042 2052 Time period P e r C a p ita G e n e r a tio n (k W h )

Per Capita Electricity Consumption Energy Resources (BTCE)

ROLE OF FBR IN INDIAN ENERGY GROWTH SCENARIO

Innovative Innovative FBRs FBRs – – Indian Approach Indian Approach

• Improved Economy

Improved Economy # High Burn # High Burn-

• up

up – – 200 200 GWd GWd/t /t # Increased Plant life : 40 60 years # Increased Plant life : 40 60 years

• Sustainability

Sustainability # # High Breeding High Breeding – – Metallic Fuels Metallic Fuels

• Enhanced Safety

Enhanced Safety

Materials Development Program Materials Development Program & & Addressing Issues for Addressing Issues for

• Extending burn

Extending burn-

• up to 200

up to 200 GWd GWd/t /t

• Increasing life of Reprocessing Plants

Increasing life of Reprocessing Plants

• Increasing Breeding by Metal Fuels

Increasing Breeding by Metal Fuels

Plan of the Presentation Plan of the Presentation

Fuel Cycle Cost Variation with Fuel Cycle Cost Variation with Burn Burn-

• up

up

FR Burn-up (MWd/Kg) Relative fuel cycle cost

I MPORTANCE OF HI GH BURN-UP

IN FBRs, 200 GWd/t BURN-UP IS DESIRED TO

• LOWER UNIT ENERGY COST

Due to reduced amount of fuel fabricated and processed per MWe

• MINIMISE WASTE GENERATION

Less Minor Actinides and Fission Products per MWe

• REDUCE MAN REM EXPOSURE

per MWe

EPR EFR +20% EFR+30% Investment 56 67 73 O & M 25 30 32 Fuel 19 9 9 Total cost 100 106 114 EFR vs EPR generating cost Comparison normalised to 100% EPR , ,

EPR+ 20%

EPR EPR+20% EPR+30%

COMPREHENSIVE MATERIALS DEVELOPMENT STRATEGY MATERIALS FOR FUTURE FBRs REACTOR PARAMETERS REPROCESSING HIGH LEVEL WASTE MANAGEMENT

Strategy for 200 GWd/t Burn-up

Issues Related to High Burn-up

In-Pile Behavior of Fuel Element & Subassembly

• Deformation, Fuel Clad Chemical Interaction

Degradation in Mechanical Properties Fuel Cycle Aspects

Research & Development - Multi Disciplinary

Reactor physics Fuel Properties Structural Material Properties Core engineering

PIE Modeling

Reprocessing and Waste Management

Integrated and Synergistic Approach

200 100 Peak fuel burn-up (Gwd/t) 1/4 1/3 Fraction of core discharge per cycle 23/31 21/28 Fuel enrichment (%) 270 180 Cycle length (full power days) Future Present Parameter

Enhance Excess Reactivity of Fuel at Beginning of Cycle – Residence time Excess Reactivity

Residence time t1

t2

1

eff

k k Δ = −

Excess reactivity:

2 1

k k Δ > Δ

1

k Δ

2

k Δ

Low BR

High BR t1 t2

Excess Reactivity

Residence time

Reduce Reactivity Fall with burnup by higher breeding ratio (BR) - Residence time

REACTOR PHYSICS MEASURES FOR HIGH BURN-UP

Fissile Content High in FBRs – High Burn-up Achievable

IMPROVED PFBR OXIDE CORE

CORE ENGINEERING FOR 100 CORE ENGINEERING FOR 100 GWd GWd/t /t

FBTR: Mk –I Fuel Subassembly PFBR: Fuel Subassembly

Fuel : (U-Pu)O2 Peak Linear Power : 450 W/cm Clad material : 20%CW D9 Wrapper material: 20%CW D9

• No. of pins

: 217 Fuel : (70%PuC-30%UC) Peak Linear Power : 400 W/cm Clad material : 20%CW 316 Wrapper material: 20%CW 316L

• No. of pins

: 61

25 GWd/ t BURN-UP 50 GWd/ t BURN-UP 100 GWd/ t BURN-UP

Burn-up Limited by Clad Ductility and Assembly Interaction

Microstructure

• f Fuel pin

cross section at centre of fuel column EXCELLENT PERFORMANCE OF FUEL / CLAD / HEXCAN NO FUEL/CLAD GAP SEEN AT THE CENTRE OF FUEL COLUMN INTERNAL CLAD CARBURISATION NOT OBSERVED MAXIMUM INCREASE IN CLAD DIAMETER - 1.6% RESIDUAL DUCTILITY OBSERVED ON THE CLAD TUBE - 3% CLAD VOLUMETRIC SWELLING ESTIMATED TO BE 4.4%

FUEL HAS REACHED 154 GWd/t BURN-UP WITHOUT FAILURE

PIE OF 100 GWd/t FBTR CARBIDE FUEL

BG = BR-1

0.05 0.10 0.12

Present design 3 Rows

• f radial

blanket Bottom axial blanket increased by 10 cm Ferritic steel for hexcan 1% Increase each of smear density & volume fraction

• f fuel

0.08 0.095 0.105 0.125

Breeding gain increase with design improvements

Improvements in design & materials

Oxide Core for Higher Breeding Gain (BG)

ENGINEERING CONSEQUENCES OF SWELLING & IRRADIATION CREEP

S – Swelling Component (isotropic) C – Creep Component SUBASSEMBLY BOWING & AXIAL GROWTH WRAPPER DILATION S C

Handling Force Limit -15 kN Handling Force for 100 GWd/t - 6 kN

Intense Neutron Flux (1015n/cm2/s) FAST REACTOR STRUCTURAL MATERIALS High Temperature 400-700oC- clad 400-600oC wrapper DISPLACEMENT DAMAGE VOID SWELLING Irradiation Creep

• Radiation damage is the major consideration

Dimensional Changes Due to Swelling and Creep Limit Burnup

100 – 200 dpa

Fuel Subassembly Fuel Subassembly -

• Clad & Wrapper

Clad & Wrapper

• Increasing fission gas plenum

Increasing fission gas plenum

• Decreasing the smeared density

Decreasing the smeared density

• Annular pellet concept

Annular pellet concept

Fission Gas Plenum Pellet Central Hole

Fuel Pin Schematic

Fuel Blanket Spring Clad

ENGINEERING DESIGN MEASURES FOR HIGH BURNUP

Bowing Reduction Bowing Reduction

• More number of

More number of flow zones flow zones

• More enrichment

More enrichment zones zones

Reduction of Fuel Clad Reduction of Fuel Clad Chemical Interaction Chemical Interaction

• Higher allowance in

Higher allowance in clad thickness clad thickness

• Lower O/M ratio

Lower O/M ratio

Clad Annular Pellet

ENGINEERING DESIGN MEASURES FOR HIGH BURNUP

• Increase in O/M ratio

Increase in O/M ratio -

• oxidation of clad
• xidation of clad
• Clad corrosion due to fission products

Clad corrosion due to fission products

• Cladding stress due to higher fission gas release

Cladding stress due to higher fission gas release

• Fuel

Fuel-

• coolant interaction

coolant interaction Above issues are not life limiting up to 200 GWd/t Burn-Up Oxide Fuel is Well Proven for High Burn-up with Advanced Materials

Oxide Fuels achieved 13-16 at% burn-up -Internationally 24 at% - Experimental Pins

HIGH BURN HIGH BURN-

• UP ISSUES IN OXIDE FUELS

UP ISSUES IN OXIDE FUELS

Relative Thermal Conductivity of 56 GWd/t burnt UO2 fuel at 1273 K Ref: H. Sakurai and Y. Wakashima Nippon Nuclear Fuel Dev.Co., Ltd., Japan.

• Thermal

Conductivity Degradation at High Burn-up

• Need for

Measurement of Fuel Conductivity

THERMAL CONDUCTIVITY OF HIGH BURN THERMAL CONDUCTIVITY OF HIGH BURN-

• UP FUELS

UP FUELS

Issues Related to High Burn Issues Related to High Burn-

• up

up

• Core Engineering

Core Engineering

• Reactor Physics

Reactor Physics

• Materials Development (Fuel, Clad &

Materials Development (Fuel, Clad & Wrapper) Wrapper)

• Impact of high burn up on Reprocessing

Impact of high burn up on Reprocessing

• Waste Management

Waste Management

Demands on the Core Structural Materials

Reliability Durability Economy

Swelling Resistant Materials

VOID SWELLING; IRRADIATION CREEP; H.T. PROPERTIES Development of advanced clad and wrapper materials for achieving burn-ups

• f ~ 2,00,000 MWd/t initiated

Clad : Development of improved version of D9 (D9I) by optimisation of minor alloying elements; Si, Ti and P (better void swelling resistance) Wrapper : Optimised mod.9Cr-1Mo steel with controlled residuals to improve ductile to brittle transition temperature

Alloy D9 Alloy HT9

B.J. Makenas et. al, 1990

Fuel Fuel -

• Oxide or Metal

Oxide or Metal Clad & Wrapper Clad & Wrapper

Ferritic / Martensitic Steels

9Cr-1Mo; Mod. 9Cr-1Mo-V-Nb

9Cr-2Mo-V-Nb; 12Cr-1Mo-V-W;

Current generation Immediate Future Future

Oxide dispersion strengthened (ODS) steels 13Cr-1.5Mo-2.9Ti-1.8Ti2O3, 13Cr-1.5Mo-2.2Ti - 0.9Ti2O3-0.5Y2O3, 12Cr-0.03C-2W- 0.3Ti- 0.24Y2O3,9Cr - 0.13C- 2W + Ti + Y2O3

Reprocessing - Stainless steel, Ti & Zr based

alloys, Ceramic & Nano Coatings

Waste management – Synroc & Glass Matrices

Austenitic stainless steel Austenitic stainless steel Type 316 & modifications Type 316 & modifications

15Cr 15Cr-

• 15Ni

15Ni-

• Ti

Ti-

• C (Alloy D9) &

C (Alloy D9) & its improved versions its improved versions

Choice of Materials for High Burn Choice of Materials for High Burn-

• up

up

Ferritics – DBTT Austenitics – Void Swelling

Materials Performance Materials Performance – – Identified Problems Identified Problems

DIAMETRAL DEFORMATION (%)

3 55 35 1 2 5 4 6 CW 316 7 8 CW 15-15 Ti 135 95 75

DOSE (dpa)

115 CW Si-MOD 15-15 Ti CW 316 Ti

• 9Cr-1Mo

9Cr-1Mo-V-Nb

70 - 110dpa (T) (T) (L) (L )

Transverse (T) & Long. (L)

• Meas. directions

FOCUS AT IGCAR

Materials modeling Processing- Grain boundary Engg. Weldability studies NDE methods High Temp Mechanical Properties - Evaluation New experimental methods – Materials evaluation Alloy Design – Control of tramp elements Irradiation Studies

IMPROVED AUSTENITIC STAINLESS STEEL MATERIALS IMPROVED AUSTENITIC STAINLESS STEEL MATERIALS

• Increase Ni and decrease Cr

Increase Ni and decrease Cr

• Solute elements like Ti, P,

Solute elements like Ti, P, Nb Nb, C play dominant roles in , C play dominant roles in determining void swelling resistance determining void swelling resistance Current Focus & Choices of Materials Current Focus & Choices of Materials 15Cr 15Cr-

• 15Ni

15Ni-

• Ti (D9, D9I

Ti (D9, D9I -

• USA, India), PNC 316, PNC 1520

USA, India), PNC 316, PNC 1520 (Japan), 15 (Japan), 15-

• 15 Ti,

15 Ti, Si Si mod.15 mod.15-

• 15 Ti (France)

15 Ti (France)

• Swelling resistance

Swelling resistance -

• unacceptable beyond 120

unacceptable beyond 120 dpa dpa Chemical Composition – Major Alloying Elements (Ni,Cr) Minor Alloying Elements (C, Ti, Si, P, Nb & B) Thermo-Mechanical Treatment - Cold working, Solution Annealing Temperatures, Precipitation

100 1000 10000 100 300 200

ALLOY D9 MIDHANI

Ti/C = 4 Ti/C = 6 Ti/C = 8

Stress, MPa Rupture Life, h

Log-log plots of applied stress versus rupture life

High magnification HREM image of 20% CW D9 showing Moire fringes due to fine scale TiC

DESIGN PRINCIPLE OF AUSTENITICS TOWARDS HIGH dpa

Austenite matrix strained area close to precipitates. Inset has been Fourier filtered to highlight lattice defect contrast

To reduce void swelling

# Cold work # Fine precipitates of TiC

ACCIDENTAL DISCOVERY OF ABSENCE OF VOIDS IN FERRITE

DEVELOPMENT OF FERRITICS FOR FBR

α

• Not suitable for clad due to poor high temperature characterist

Not suitable for clad due to poor high temperature characteristics ics

• Very attractive for wrapper due to lower operating temperature

Very attractive for wrapper due to lower operating temperature (creep strength is not a primary requirement) (creep strength is not a primary requirement)

• Ductile to brittle transition temperature (DBTT) increases due

Ductile to brittle transition temperature (DBTT) increases due to to radiation (lowest for 9 Cr radiation (lowest for 9 Cr – – 1 Mo) 1 Mo)

• Lower operating temperature for metallic fuel

Lower operating temperature for metallic fuel -

• use of

use of ferritic ferritic steels steels for clad at high for clad at high dpa dpa can be explored can be explored 9 9-

• 12 % Cr

12 % Cr ferritic ferritic-

• martensitic

martensitic steels steels-

• excellent swelling resistance

excellent swelling resistance upto upto 200 200 dpa dpa 9Cr 9Cr-

• 1Mo , Mod. 9Cr

1Mo , Mod. 9Cr-

• 1MoVNb

1MoVNb 9Cr 9Cr-

• 2MoVNb , 12Cr

2MoVNb , 12Cr-

• 1MoVW

1MoVW 9Cr-1Mo & modified versions are excellent Choice for Wrapper ; Promise up to 200 dpa; DBTT issue to be addressed

DEVELOPMENT OF FERRITICS

Comparison of shift of DBTT after irradiation for the mod.9Cr- 1Mo and HT9 Formation of brittle α′ and chi phase easier in 12Cr-1MoVW steel irradiated at 420 °C in FFTF to 35dpa

DBTT & UPPER SHELF ENERGY – MORE FOR 12Cr BOTH INSENSITIVE TO TEMPERING TIME

(a) DBTT and (b) USE as a function of displacement damage for 9Cr- 1MoV Nb and 12Cr-1MoVW steels with four different heat treatments and irradiation at 420°C in FFTF

FERRITICS - ISSUE OF EMBRITTLEMENT

FERRITICS FAVOURABLE BOUNDARIES Low misorientation angle inhibits segregation

• f metalloids

ROUGUE BOUNDARIES Promotes segregation

• f P, S, Sb

REDUCE NUMBER OF UNFAVOURABLE BOUNDARIES

USE ORIENTATION IMAGING MICROSCOPY To IDENTIFY THESE BOUNDARIES BY ANGLE OF MISORIENTATION

Typical Input Data in Orientation Imaging Microscopy

Steel: Mod. 9Cr1Mo steel - Normalised, Tempered (760oC / 1hr) & Aged (550oC / 8400 hrs)

Grain Boundary Engineering (GBE) Grain Boundary Engineering (GBE) -

• To overcome

To overcome embrittlement embrittlement

Future Directions in Development of Claddings

• Nano-engineered ODS Ferritic/Martensitic Steel
• Innovative Material for Claddings

Oxide Dispersion Strengthened Steels (ODS) – Choice for Clad

Excellent Creep Resistance, Increased high temperature mechanical properties, DBTT close to room temperature

Issues To be Addressed – Tube Fabrication, Welding

• Current ODS steel manufacturing is not cost-effective
• Nano engineering of powder particulates with built in nano structural

features holds promise – involves CVD, Fe-carbonyl, Cr-carbonyl , Tungsten Carbonyl, Yttrium Isopropoxide on Fe seed particles

• Consolidation by press extrusion technique - Improved control over

microstructure (dispersant size, composition, distribution and uniformity) resulting in high creep strength

Excellent Choice for Clad – Promise up to 200 dpa Development to be taken up - DBTT issue to be addressed

Creep strength increases with increase in Ti & Y2O3 content in 9Cr-2W-0.13C-Ti-Y2O3 ODS martensitic steel

Better creep strength

than Austenitics

DBTT is close to

room temperature

No carbon leaching

in sodium environment

Ferritic structure has

better resistance to neutron damage and better void swelling resistance

9Cr ODS Martensitic Steel Claddings

Conventional Ferritic-Martensitic SS

973 K

Stress for 200 GWd/t M91 M93 M92 M11

Conventional Ferritic martensitic steel

0.37 0.37 0.2 0.2 M11 M11 0.35 0.35 0.2 0.2 M93 M93 0.30 0.30 0.2 0.2 M92 M92 0.34 0.34 0.12 0.12 M91 M91 Y Y2

2O

O3

3

Ti Ti Code Code

Materials Modeling Materials Modeling

Molecular Dynamics Density Functional Theory calculation of Physical Properties Car- Parinello MD ABINIT VASP SIESTA WIEN-2K MDCASK Codes Installed, Codes Installed, Parallelised Parallelised Cascades for 5, 10, and 100 keV cascades in Cu at 100K

FINITE ELEMENT SIMULATION OF SQUID-BASED EDDY CURRENT NON-DESTRUCTIVE EVALUATION OF CYLINDRICAL TUBES

200 300 400 500 600 8.05 8.10 8.15 8.20 8.25 8.30 8.35 8.40 8.45 8.50 8.55

SQUID OUTPUT (V) Angle of rotation (degrees)

• 30
• 20
• 10

10 20 30

Flaw width:1 mm Height 7 mm; Computed with 2D-exciter

Bnormal (nanoTesla)

1

Source

iσω μ ⎛ ⎞ ∇ × ∇ × = − ⎜ ⎟ ⎝ ⎠ A J A

X-Y Scanner

SQUID output vs distance of the weldment sample after magnetisation

• 5

5 10 15 50 100 150 200 250 300 Distance (mm) SQUID output (Φ 0)

15.2954 Φ 0 6.67455 Φ 0 5.26860 Φ 0 4.89565 Φ 0 3.90938 Φ 0 3.90857 Φ 0

* virgin * 50 cycle * 100 cycle * 150 cycle * 200 cycle * 250 cycle

Sample : Stainless steel 316 L(N) Temperature : 600 oC, Strain rate : 3x10-

3s-1

SQUID output Vs No. of cycles

• f the weldment sample

2 4 6 8 10 12 14 16 18 50 100 150 200 250 No of cycles SQUID output (Φ0)

SQUID -NDE

NEW TECHNIQUES FOR MATERIALS EVALUATION -

• SQUID based remnant magnetization measurements - Measurement of δ-ferrite

content in SS316 L(N) weld joint

PAS Studies on D9 Alloy PAS Studies on D9 Alloy

Onset of TiC shifts to low temp With increasing Ti/C ratio Maximum TiC pptn for Ti/C=6

400 600 800 1000 1200 110 120 130 140 150 160 170 Ti/C=4 Ti/C=6 Ti/C=8 Ti free Model alloy Solution Annealed State

τ (ps)

Annealing Temperature (K)

Effect of Ti/C ratio

Effect of Cold work Onset of TiC shifts to low temp with increase in cold work

• Max. TiC precipitation for 20%CW

SQUID and Positron Annihilation techniques can be deployed advantageously for fine measurements of radiation damage and link them to performance

Two signatures of point defects prior to void formation

• Disappearance of high order Laue zone rings &
• Interference fringes within (000) disc of CBED pattern

NORMAL ELECTRON DIFFRACTION GEOMETRY CONVERGENT BEAM ELECTRON DIFFRACTION

SIG NATURES IN CBED FO R PO INT DEFEC TS

α -Al Al6M n α -Al Al6M n

incident beam

diffraction pattern

incident beam

diffraction pattern

NEW TECHNIQUES FOR MATERIALS EVALUATION - CBED FOR POINT DEFECTS

Looking Forward to Looking Forward to Ductile Ductile Ferritics Ferritics Easily Easily Fabricable Fabricable ODS ODS

Impact of high burn up on Impact of high burn up on Reprocessing Reprocessing

In-vessel Cooling Decay Heat W/kg of HM Activity Ci/kg of HM 3 months 104 4.01 x 104 6 months 69 2.54 x 104 9 months 52 1.90 x 104 12 months 42 1.54 x 104

• Specific activity of the irradiated fuel decides the

Specific activity of the irradiated fuel decides the R&D requirement of reprocessing. R&D requirement of reprocessing.

• Specific activity is more for fuels irradiated for

Specific activity is more for fuels irradiated for higher burn higher burn-

• up because of the presence of more

up because of the presence of more fission products and long fission products and long-

• lived actinides

lived actinides

Decay heat and specific activity for PFBR Fuel with 200 GWd/t Limit is 50 W/kg 100 GWd/t - 30 W/kg (240 d cooling) 200 GWd/t - 42 W/kg (360 d cooling) Fission Product Activity Dominates

• ver Minor actinides

and tend to Saturates at high burn-up

Fuel Reprocessing Issues Fuel Reprocessing Issues

Increase in yield of dissolver off-gases Increased quantities of insoluble Pu-noble metal alloy residues formation resulting in higher Pu losses Higher radiation damage to Solvent and diluent Higher radiation damage to Elastomers and Polymer-Ceramic Composites Radiation induced damage to protective films on materials of construction

REPROCESSING REPROCESSING -

• ISSUES RELATED TO HIGH BURN

ISSUES RELATED TO HIGH BURN-

• UP

UP

PROCESS

Methods for recovery of Pu from insolubles Pu-noble metal alloy residues Highly efficient off-gas clean up systems Technology and equipment for noble gas (Kr, Xe) removal Better solvent wash systems Separation of Nuclides of societal benefits Development of alternate solvents (e.g. TiAP, Amides)

MODELING

Modeling and characterisation of insoluble residues for Pu recovery Actinide distribution and Thermophysical data for new solvents & extractants Flowsheet developments for long lived fission products and minor actinides separation

R&D for Reprocessing High Burn R&D for Reprocessing High Burn-

• up Fuels

up Fuels

Redefining Reprocessing: Recovery of ALL valuable elements from irradiated fuel

TAP/Amides Based Advanced PUREX Extraction Disassembly & Dissolution

Spent Fuel U+Pu U MOX Fuel FF Np Tc FBR Park

Actinide Partitioning and Group Separation Deep Underground Geological Disposal & Monitoring FBR/ADS Based P&T

Ln/ Other FPs HAW HAF Actinides MOX Fuel Hulls, SW and Insolubles

129I

90Sr,137Cs, PGM

recovery Applications: 137Cs - Irradiation, 90Sr - Heat Sources, PGM - catalyst etc

☼ ☼ Fast reactor fuels at high burn

Fast reactor fuels at high burn-

• up

up -

• significant amounts of

significant amounts of noble metal fission products ( noble metal fission products (Ru Ru, , Rh Rh, Pd) , Pd)

☼ ☼ Ru

Ru, , Rh Rh, Pd , Pd -

• problems in

problems in vitrification vitrification steps steps

☼ ☼ Pd from fission

Pd from fission – – a useful a useful product product

☼ ☼ Processes need to be

Processes need to be developed for noble metals developed for noble metals recovery in addition recovery in addition to to minor actinides minor actinides

☼ ☼ Besides noble metals, Cs &

Besides noble metals, Cs & Sr Sr also can be recovered and also can be recovered and used in variety of applications used in variety of applications

Element Qty (g/kg)

(100 GWd/t)

Palladium 10 Ruthenium 50 Rhodium 5 Cesium 20 Strontium 2 Wealth from Waste

Materials Issues for Waste Management Materials Issues for Waste Management

Studies at IGCAR on Pd Recovery using non Studies at IGCAR on Pd Recovery using non-

• aqueous solvents

aqueous solvents

Pd has good solubility in Room

• Temp. ionic liquid butyl methyl

imidazolium chloride (bmimCl)

Redox chemistry of Pd in

bmimCl and aliquat 366 studied

Electrodeposition of Pd from

these solvents established

F ig u re 4 . X R D p a tte rn o f p a lla d iu m d e p o s it D e p o s it fro m a liq u a t - 3 3 6 D e p o s it fro m b m im C l-P d C l2

Intensity 2 θ

[PdCl4]2-

F ig u re 1 . U V -V IS ab s o rp tio n sp ec tru m o f b m im C l-P d C l2 P d C l2 d is so lv ed in b m im C l 1 .7 m m o la l P d 2 .2 m m o la l P d 3 .4 m m o la l P d 4 .5 m m o la l P d 4 .7 m m o la l P d

Absorbance W ave L en g th , n m

[PdCl3]-

• 2.5
• 2.0
• 1.5
• 1.0
• 0.5

Electrochemical window of bmimCl

Cyclic Voltammograms of bmimCl and palladium dissolved in bmimCl at 70°C

2 mA bmimCl -switching potential at -2.2 V bmimCl -switching potential at -1.9 V

Potential (Vs. Pd), V

Pd oxidation to [PdCl4]

• Pd oxidation to

[PdCl3]

• Pd deposition
• r reduction

0.2 mA

[Pd] = 40 mmolal in bmimCl scan rate 10 mV/s Current

Cans with simulated synroc after hot isostatic pressing

Immobilisation Immobilisation of Waste from Processing of High Burn

• f Waste from Processing of High Burn-
• up Fuel

up Fuel

• Glass matrix

Glass matrix – – demands reduction in waste loading through recovery of fission demands reduction in waste loading through recovery of fission products products

• Synthetic rock (

Synthetic rock (Synroc Synroc) like matrix ) like matrix – – under development under development – – HLW HLW

• 100g size monoliths fabricated and

100g size monoliths fabricated and characterised characterised (IGCAR (IGCAR-

• BARC

BARC-

• DMRL

DMRL Collaboration) Collaboration)

• Bulk synthesis & fabrication of

Bulk synthesis & fabrication of Synroc Synroc monoliths containing simulated HLW monoliths containing simulated HLW expected from FBTR in progress (IGCAR expected from FBTR in progress (IGCAR-

• BARC

BARC-

• NCL

NCL-

• DMRL Collaboration)

DMRL Collaboration)

• Our studies

Our studies – – Synroc Synroc C efficient for C efficient for immobilising immobilising high level waste high level waste

Materials Development for Increasing the Life

• f Aqueous Reprocessing Plants

Nitric Acid Loop For Corrosion Assessment Nitric Acid Loop For Corrosion Assessment

Features

Temp.: 40, 60, 80, 107oC & vapour phase, 6N HNO3, 360 ltrs Flow rate: ~ 1 m/s, Fitted with corrosion probes & leak detectors Materials 304L SS (FRFRP), 304L SS (NAG) in annealed, sensitized, welded conditions Current status Operation for 100, 250, 500, 1000 (1) and 1000 (2) hrs periods;Corrosion rate evaluated, NDT evaluation of samples Testing Plan Exposure for 1000 hr and then every 1000 hrs with intermittent corrosion assessment FSA : Solution Annealed FAW : As Welded MNSA : NAG SS (MIDHANI)

Solution annealed 304L SS in boiling acid

100 h 250 h 500 h 1000 h 2 x 1000 h after 250 h after 500 h after 1000 h after 2 x 1000 h

CORROSION RESISTANT ALLOYS BETTER THAN Ti & Ti –Ta alloys

Ti - 5Ta-1.8Nb - Alternate Material with High Corrosion Resistance

1- β- ANNEALED, 2 STRESS RELIEVED – TMP, 3 MILL ANNEALED, 4 SOLN. TREATED & AGED

Corrosion Rate (mpy)

BOILING 11.5 N HNO3 VAPOUR PHASE TRICKLE ZONE CONDEN SATE

1 2 3 4 Highlights of Studies

Thermomechanical Processing Route & Heat Treatment Optimised Phase Transformations Mechanisms studied 3 phase Corrosion & Mechanical Properties studied Weldability established Texture & Microtexture studied

Orientation mapping

• f alpha colonies

√

Favourable structure

Unfavourable structure Optimum microstructure with minimum corrosion rate & good mechanical properties

D Double

• uble O

Oxide xide C Coating on

• ating on T

Titanium itanium f fO Or r R Reconditioning (DOCTOR) econditioning (DOCTOR)

Higher iron content (> 0.05%) and embedded iron

particles in Ti result in high corrosion rates in boiling HNO3 (> 18 mils per year)

Corrosion

resistance

• f

such titanium components could be reduced to about 5 mils per year through an anodic passivation technology. PASSIVATION METHODOLOGY

Chemical cleaning of Ti in HNO3+HF solution to

remove iron contamination, scale etc.

Anodising in HNO3 solution containing HF, Ru3+

and Cr6+ ions for forming TiO2 coating

Anodising

in ammonium persulphate for thickening and stabilising TiO2

Conditioning of the surface by immersion in

boiling distilled water

Condensate Corrosion DOCTOR Coating

Removal

• f

iron contamination and formation of nanograined (200 - 300 nm) TiO2 oxide particles enhanced the corrosion resistance of titanium in nitric acid

Electrode Materials Development Electrode Materials Development

ELECTROCHEMICAL PROCESSES Electrolytic Dissolution and Conditioning Electrolytic Partitioning Electrolytic Uranous (U4+) Production Electrolytic Acid Killing Electrolytic Destruction

• f Organics and wastes

CONDITIONS OF ELECTROLYSIS Medium - Nitric Acid Temperature - RT to Boiling Acid - dilute to concentrated Voltage - up to 6 V Redox Ions - FPs, Ag, Cr, Fe etc. COATINGS ON TITANIUM MOCTA Thermal Decomposition Plasma Processing RuO2+TiO2, RuO2+TiO2/PtO2 MOCTAG Thermochemical Glazing Platinum, Pt + Iridium Longer life of MOCTAG and PMMOCTA compared to MOCTA in boiling 10 N HNO3 medium during electrolysis

PMMOCTA

Materials for Metal Fuel Cycle

Design for High Breeding Ratio

BARC-& IGCAR Collaborative programmes for optimisation of Zr content (0 to 6%) for increasing BR Test fuel pin fabrication and irradiation in FBTR Out of pile Fuel-Clad Chemical Interaction studies Thermo-physical property measurements on fuel alloys 1.37 1.37 13.6/18.2 13.6/18.2

5% 5% Zr Zr

3 blanket 3 blanket rows rows 1.52 1.52 1.3 1.3 2 blanket 2 blanket rows rows 1.49 1.49 1.25 1.25 Breeding Ratio Breeding Ratio 12.1/16.2 12.1/16.2 15.4/20.6 15.4/20.6 Pu Pu Content Content

Remarks Remarks 0% 0% Zr Zr 10% 10% Zr Zr Zr Zr Content Content

FOR FUEL : U-Pu-Zr(0 to 6%) FOR CLADDING : Mod. 9Cr-1Mo-V-Nb STEEL FOR WRAPPER : 9Cr-1Mo STEEL

Material Development for METALLIC FUEL

Development of Mechanically Bonded Metal Fuel Pin

# Mechanically bonded fuel pin with U-Pu binary alloy # Either a Zr liner between the clad and fuel or Cr/W coating inside the clad # Highest possible breeding ratio # Eliminates need for sodium bonding # Amenable for fabrication in hot cells # Studies pursued at BARC on swaging of fuel, liner and clad # Swaging U rod, Zr- 4 tube and D9 successful # Grooves on U by swaging to accommodate swelling

LiCl-KCl, 500°C

Schematic Diagram of Electrorefining Process

U deposit

Spent Metal Fuel

U To metal fuel fabrication

deposit Molten Cadmium layer

Material Issues for Metal Fuel Cycle # Metallic fuels will be reprocessed by Pyrochemical Method # Compatibility with chloride salts # Compatibility with Cadmium – Nickel free materials # Compatibility with liquid U and Pu (in consolidation step and Injection casting)

Injection Casting Set up

Need for coating development

O

2-

Cathode Anode

LiCl/ CaCl2

Ca.3V

Oxide to metal conversion

Oxide

# Direct Oxide Reduction Process- Essential for transition from oxide to metal fuel cycle # Corrosion problems are higher due to presence of oxygen and chloride salt # Pt anode reacts with many anions

# Need for developing ceramic

• r ceramic coated metal anodes

Material I ssues for Metal Fuel Cyle (contd.) .

Salt preparation vessels - High temperature Ni-base

cast/electroformed containers with corrosion resistant ‘graded’ ceramic composite coatings

Consolidation of cathode deposit –

• Pyrographite coated crucibles and containers and accessories
• Zirconium silicate and Zirconium yttrate coated crucibles

Developments Envisaged

Injection casting - High-silica ‘Vycor’ tubes with ZrO2

coating, graphite crucible with ZrO2 coatings; Reusable moulds ??

Corrosion monitoring of crucibles and containers, and

establishing online monitoring noninvasive NDT and electrochemical techniques Development of Container Material and Coatings for Pyroprocess Applications Developments in Progress

Casting of Prototype Type 316L SS Vessel Casting of Prototype Type 316L SS Vessel

Investment Casting Process

600 h x 312 w x 20 t, mm, as cast and sand blasted, Before machining

Plasma Sprayed Zirconia Coating for Pyrochemical Reprocessing

316L SS, NiCrNiY Bond Coat (50 μm), Yttria Stabilised Zirconia (350 μm) Testing up to 200 h at 600°C in molten LiCl + KCl

MOSTA

Laser melting using CO2 CW laser at 100 W Glazed and smooth surface High hardness (from 750 to 1200 Hv) Metastable phase formation Cellular structure

As-coated Laser melted Cubic + tetragonal Cubic + tetragonal + t*

100 h tested Weight loss = 0.06 mg As-coated

1230 VHN 664 VHN 249 VHN

laser melted

Management of Waste from Management of Waste from Pyroprocessing Pyroprocessing

Two types of waste forms envisaged Two types of waste forms envisaged ♣ ♣ Metal waste form for cladding hulls,

Metal waste form for cladding hulls, Zr Zr, Noble metal fission , Noble metal fission products, actinides (from electro products, actinides (from electro-

• refiner anode)

refiner anode) – – our approach is to recover valuable noble metals from

• ur approach is to recover valuable noble metals from

anode before fabricating metal waste form anode before fabricating metal waste form ♣ ♣ Ceramic waste form for Ceramic waste form for Fp’s Fp’s in in LiCl LiCl – – KCl KCl salt bath salt bath [Alkali, Alkaline Earth & Rare Earth] [Alkali, Alkaline Earth & Rare Earth] – – our approach is to recover Cs and

• ur approach is to recover Cs and Sr

Sr from salt waste before from salt waste before fabricating ceramic waste form fabricating ceramic waste form ♣ ♣ Metal Waste Form Metal Waste Form : :

• Stainless steel

Stainless steel – – 15 wt% 15 wt% Zr Zr : durable alloy : durable alloy ♣ ♣ Ceramic Waste Form Ceramic Waste Form -

• Glass

Glass-

• ceramic composite

ceramic composite

• Salt (~ 10%

Salt (~ 10% fp fp) equilibrated with ) equilibrated with Zeolite Zeolite A A

• FPs

FPs removed to removed to Zeolite Zeolite by by

• Ion Exchange/ Occlusion

Ion Exchange/ Occlusion Occluded salt not Occluded salt not leachable leachable

Salt-occluded Zeolite + 25% glass frit

Sintered at 1200 K Glass bonded sodalite

Salt-loaded Zeolite Sodalite

XRD of glass-bonded sodalite wasteform (Studies at IGCAR)

Further studies at kg scale to be

taken up at IGCAR and BARC

Development of Ceramic Waste Form Development of Ceramic Waste Form

Development of Metal Waste form (IGCAR & BARC)

# Studies for the optimisation of Zr content in the waste form using simulated alloys based on microstructure # Batch size in line with the waste to be produced in the demonstration facility for pyrochemical reprocessing # Studies will be extended to Pu containing alloys

SUMMARY Strategy and Efforts are in place for Development of Materials and addressing related issues in closed fuel cycle with Fast Breeder Reactors

FAST BREEDER REACTORS Energy Security for Country’s Prosperity Energy Security for Country’s Prosperity