MODELING REACTIVE TRANSPORT IN NUCLEAR WASTE GEOLOGICAL DISPOSAL - glass/iron/clay interactions - atmospheric carbonation of concrete SeS BENCH – NOVEMBER

MODELING REACTIVE TRANSPORT IN

NUCLEAR WASTE GEOLOGICAL DISPOSAL

- glass/iron/clay interactions

- atmospheric carbonation of concrete

SeS BENCH – NOVEMBER 11.-13. 2013

CEA (French Alternative Energies and Atomic Energy Commission)

B. Cochepin, I. Munier ANDRA (French Radioactive Waste Management Agency)

21 avril 2023 | PAGE 1CEA | 10 AVRIL 2012

S. Bea (CONICET, Argentina)J. Corvisier, L. De Windt (Mines Paristech, France)D. Jacques (CEN.SCK, Belgium)N. Leterrier (CEA Saclay, France)N. Marty, F. Claret (BRGM, France)C. Steefel (LBNL, USA) D.Y. Su, U. Mayer (UBC, Canada)

DISPOSAL CONCEPT IN A CLAYSTONE FORMATION AT 500 m DEPTH

Current design of deep underground repository for high and intermediate level long-lived waste

S.S.BENCH - November 16-18. 2011

SeS BENCH – Leipzig | NOV. 2013 | PAGE 2

Update onglass/iron/clay

benchmark


DRD/EAP/11-0219

HLW DISPOSAL CELL

21 avril 2023 | PAGE 4

• different types of material in physical contact, technological gaps

long term calculations of geochemical evolution (100 000 years)

Vitrified wastepackages

Cross section

3 cm gap steel liner

disposal package

0.8 cm gap

3 cm gap

scale

• 1D radial domain

• transport: diffusion only

• water saturated, constant porosity

• isothermal conditions

• H2(g) from anoxic corrosion

pH2(max) = 60 bar

• glass

Φ = 0.42 m, H = 1 m

porosity = 0.12

• metallic components

total thickness = 0,095 m,

porosity = 0.25

• connected fractured zone

0.4 * excavation diameter = 0.268 m

porosity = 0.20; Deff(25°C) = 5.2 10-11 m2/s

• undisturbed claystone (50 m)

porosity = 0.18; Deff(25°C) = 2,6 10-11 m2/s

GEOMETRY AND TRANSPORT PROPERTIES

argilites (50 m – 183 cells)

glass (21cm – 21 cells)

overpack + lining + gaps

(13,8cm – 14 cells)

| PAGE 5

Major challenges come from:-highly reactive system (producing pH and redox perturbation)

-complex geochemical system (15 chemical elements, 80 aqueous species, 60 minerals)

BENCHMARK SUB-COMPONENTS


Problem 1: iron corrosion only (45 000 yrs)

magnetite, Ca-siderite, and greenalite dominate

(oxide) (carbonte) (silicate)

also smaller amounts of aluminosilicates

(nontronites and saponites)

POROSITY CLOGGING

modeling vs. experimental results iron/claystone at 90°C for 1 year

small amount of magnetite

siderite(-Ca), Fe-silicates

more phenomenological model for corrosion

Canister zone

0,1 µmProblem 2: iron corrosion + glass alteration (100 000 yrs) (Schlegel et al. 2007)

RESULTS IN THE BASE CASE (2)


A very good agreement is obtained between MIN3P and Crunchflow…

in the iron zone



in the glass zone



in the clay zone


21 avril 2023 | PAGE 10

But other codes (Hytec, PhreeqC, PHAST,…) failed at this point to run these cases (timestep too small, CPU time too high,…)

A change in the set up of the benchmark case is under way in order to get more codes to run:-progress with Hytec-PhreeqC-based codes…??-Anyone else…?

Update onconcrete carbonation

benchmark


DRD/EAP/11-0219

DESIGN: ILLW CELLS, SHAFTS (AND SEALS), ILLW DISPOSAL OVERPACK

Atmospheric carbonation of overpack during the operating period


| PAGE 12

• Bitumized waste• Compacted metallic waste• Organic waste

SeS BENCH – Leipzig | NOV. 2013

DRYING AND CARBONATION PROCESSES OF ILLW OVERPACK


Dry air

(Rh = 40 %)

T = 25°C to 50°C

SlWater vapor diffusion

CO2 gas diffusion

T

Aqueous diffusion of reactants

Two phase water/air flow

Dissolution/precipitation : porosity reduction, permeability variations

Brine formation

CO2 gas dissolution

Dry air

(Rh = 40 %)

T = 25°C to 50°C

SlWater vapor diffusion

CO2 gas diffusion

T

Aqueous diffusion of reactants

Two phase water/air flow

Dissolution/precipitation : porosity reduction, permeability variations

Brine formation

CO2 gas dissolution

| PAGE 13SeS BENCH – Leipzig | NOV. 2013

Major challenges come from:-Fast gaseous CO2 transport and highly reactive with portlandite

-Coupling capability with « multiphase » flow and transport

GEOMETRY

1D Cartesian – 5.5 cm divided in 11 cells (5 mm) for concrete 1 extra cell for “atmosphere”

Boundary conditions (EOS 4)


Symmetry axis

Dry air Dry air

Package thickness 110 mm


concrete

CASE 1/3DRYING OF CONCRETE OVERPACK


DRD/EAP/11-0219

DRYING PHENOMENON : PARAMETERS IN REFERENCE CASE

BHP CEM I


ROCK1

Density (kg/m3) 2700

Porosity 0.12

Intrinsic permeability to liquid (m²) 1e-19

Intrinsic permeability to gas (m²) 1e-17

Relative permeability m – Slr – Sls - Sgr

0.424 – 0.0 – 1.0 – 0.0

Capillarity pressurem – P0 (MPa) – Pmax (MPa) 0.424 – 15 - 1500

Molecular diffusion coefficient in gaseous phase (m²/s)

2.4e-5

Molecular diffusion coefficient in aqueous phase (m²/s)

1.9e-9

Millington-Quirk a parameter 2

Millington-Quirk b parameter 4.2

Klinkenberg parameter (MPa) 0.45


DRYING RESULTS



TOUGH2Full multiphase (EOS4)Richards (EOS9)

OK to use Richards’ equation for benchmarking exercise

Hytec (Richards’ equation)

CASE 2/3CARBONATION WITH CONSTANT SATURATION


DRD/EAP/11-0219

PHENOMENOLOGY

Constant saturation but unsaturated + diffusion of gas


Sliq = 0.3

CO2 gas diffusion

Diffusion of aqueous species

Dry AirRH = 60%

25°CpH = 13

CO2 dissolution

Precipitation/dissolution reactions

Sliq = 0.3

CO2 gas diffusion


Dry AirRH = 60%

25°CpH = 13

CO2 dissolution


Sliq = 0.3

CO2 gas diffusion


Dry AirRH = 60%

25°CpH = 13

CO2 dissolution



Sliq = 0.36

CHEMICAL PARAMETERS

Primary phases

Secondary phases

Kinetics of dissolution / precipitation

nnnn Akr 1

15,298

11exp15,298 TR

EkTk a

n

Phase Volume %

Calcite 72.12

Portlandite 5.73

CSH 1.6 13.76

Monocarboaluminate 2.26

Ettringite 3.60

Hydrotalcite 0.39

Hydrogarnet-Fe (C3FH6) 2.05

Phase type Phases

Oxides Magnetite, Amorphous silica

Hydroxides Brucite, Gibbsite, Fe(OH)3

Sheet silicates Sepiolite

Other silicates CSH 1.2, CSH 0.8, Straetlingite, Katoite_Si

Sulfates, chlorides, other salts Gypsum, Anhydrite, Burkeite, Syngenite, Glaserite, Arcanite, Glauberite, Polyhalite

Carbonates Calcite, Nahcolite

Other Hydrotalcite-CO3, Ettringite, Dawsonite

CHEMICAL PARAMETERS

Primary and Secondary phases kinetics parameters

Phase Kinétic

Constant (298.15 K)

Activation Energy

(kJ.mol-1)

Specific Surface (m2.g-1)

C3FH6 1 10-12 30 1

Calcite 1.6 10-6 23.4 1

CSH 0.8 1.6 10-9 50 1

CSH 1.2 1.6 10-9 50 1

CSH 1.6 1.6 10-9 30 1

Ettringite 1.6 10-9 30 1

Gibbsite_am 1.6 10-9 30 1

Gypsum 1.6 10-5 20 1

Hydrotalcite 1.6 10-9 30 1

Iron Hydroxyde 1.6 10-8 30 10

Monocarboaluminate 1.6 10-9 10 1

Portlandite 1.6 10-8 20 1

Sépiolite 1.6 10-12 50 10

Amorphous SiO2 1.6 10-9 30 1

Straetlingite 1.6 10-9 50 1


!Precipitation of

secondary minerals using a specific surface

area : involves a « nucleus » volume

fraction:10-4 in Toughreact

(see discussion below)

REACTION TRANSPORT RESULTS AT CONSTANT SL

Making sure the same effective diffusion coefficient is used…


For Crunchflow, b = 3.2 has to be used

(instead of b= 4.2 for Toughreact)


| PAGE 23

TOUGHREACT

MIN3P

CRUNCHFLOW HYTEC

Carbonation front is similar


| PAGE 24Calcite precipitation front is similar

TOUGHREACT MIN3P

CRUNCHFLOWHYTEC


| PAGE 25Timing not the same for all codesStraetlingite more persistent with Crunchflow

TOUGHREACT

HYTEC

MIN3P

CRUNCHFLOW


| PAGE 26

Dawsonite does not precipitate withCrunchflow and HytecStraetlingite more persistent with Crunchflow

TOUGHREACT

HYTEC

MIN3P

CRUNCHFLOW


| PAGE 27More precipitation of gypsum in the simulation with Crunchflow

TOUGHREACT

HYTEC

MIN3P

CRUNCHFLOW


| PAGE 28

Effect of the nuclei volume fraction (CRUNCHFLOW)

Vn = 10-4 Vn = 10-3

Vn = 10-2Vn = 10-1

CASE 3/3FULLY COUPLED CARBONATION


DRD/EAP/11-0219

Input parameters

Results only with Toughreact so far…

CARBONATION RESULTS

pH decrease, portlandite dissolution and calcite formation over a thickness of about 2 cm after 100 years

CARBONATION RESULTS

Dissolution of CSH 1.6, ettringite, monocarboaluminate and hydrotalcite on 2 cm after 100 years

Precipitation of CSH 1.2, CSH 0.8, straetlingite, amorphous silica and gypsum on the same thickness

Precipitation of small amounts of sepiolite, gibbsite and katoïte-Si is also predicted

CARBONATION: CPU CONCERNS…

CO2 diffusion (gas phase) and reactivity are very fast!

No SIA small time steps CPU times go up (the roof)!

CONCLUSIONS

Glass-iron-clay interactions exercise

very demanding in terms of number of minerals with large domain of kinetics coupled with a strong pH and redox perturbation

(desperately) looking for new teams to jump in!

Concrete carbonation exercise highly reactive CO2 diffusing rapidly in the gas phase

emphasizing the coupling between transport and reactions (GI vs. OS)

Sliq-dependent diffusion coefficient

[ another challenge: Sliq-dependent reactivity? ]

Direction de l’Energie Nucléaire

Département des Technologies

Nucléaires

Service de Modélisation des Transferts et

de Mesures Nucléaires

Commissariat à l’énergie atomique et aux énergies alternatives

Centre de Cadarache | 13108 Saint Paul-lez-Durance

T. +33 (0)4 42 25 37 24 | F. +33 (0)4 42 25 62 72

Etablissement public à caractère industriel et commercial | RCS Paris B 775 685 01921 avril 2023

| PAGE 35

CEA | 10 AVRIL 2012

THANK YOU FOR YOUR ATTENTION

Acknowledgements:S. Bea (CONICET, Argentina)J. Corvisier, L. De Windt (Mines Paristech, France)D. Jacques (CEN.SCK, Belgium)N. Leterrier (CEA Saclay, France)N. Marty, F. Claret (BRGM, France)C. Steefel (LBNL) D.Y. Su, U. Mayer (UBC, Canada)

POSSIBLE EXTENSION:SATURATION-DEPENDENT CHEMICAL REACTIVITY

Considerable reduction in the amplitude of carbonation (less dissolution of portlandite and CSH 1.6 and less precipitation of amorphous silica and other secondary CSH)

Lower reactivity accompanied by a greater penetration of carbonation front due to lower consumption of CO2 at the surface

Effect of water content on reactivity (Bazant type function)

CONCLUSIONS

Drying process of 11 cm thick waste packages depends strongly on the concrete nature and slightly on the flow model (Richards or full multiphase)

Considering full multiphase model, carbonated depth is about 1 cm after 100 years for the High Performance Concrete. degraded thickness is totally carbonated (total dissolution of primary mineral phases)

If we consider a chemical reactivity depending on the liquid saturation (Bazant type function), a considerable reduction in the amplitude of carbonation and a greater penetration of carbonation front are observed.

Progress areas include:

• taking into consideration a protective effect of secondary minerals

• improving knowledge on kinetics parameters and thermodynamic data, especially for CSH with low Ca/Si ratio

• coupling this system with corrosion of rebars

Documents

MODELING REACTIVE TRANSPORT IN NUCLEAR WASTE GEOLOGICAL DISPOSAL - glass/iron/clay interactions - atmospheric carbonation of concrete SeS BENCH – NOVEMBER